WorldWideScience

Sample records for catchment basins

  1. Groundwater : site scale, catchment scale, basin scale

    OpenAIRE

    Bricker, Stephanie; Bloomfield, John; Gooddy, Daren; MacDonald, David; Ward, Rob

    2011-01-01

    There are significant groundwater resources in the Thames Basin (Figure 1) supporting approximately 40 per cent of public water supply. Additionally many of the rivers in the catchment are supported by groundwater from the underlying aquifers. Effective management of both groundwater resources and groundwater-dependent ecosystems requires a good understanding of how our aquifers behave. We must also consider how these systems will respond to future changes, in particular climat...

  2. Isotope hydrology of catchment basins: lithogenic and cosmogenic isotopic systems

    Energy Technology Data Exchange (ETDEWEB)

    Nimz, G. J., LLNL

    1998-06-01

    also be treated as a mostly closed system for mass balance considerations. It is the near closure of the system that permits well- constrained chemical mass balance calculations to be made. These calculations generally focus of lithogenic solutes, and therefore in our discussions of lithogenic nuclides in the paper, the concept of chemical mass balance in a nearly dosed system will play an important role. Examination of the isotopic compositions of solutes provides a better understanding of the variety of processes controlling mass balance. It is with this approach that we examined the variety of processes occurring within the catchment system, such as weathering and soil production, generation of stormflow and streamflow (hydrograph separation), movement of soil pore water, groundwater flow, and the overall processes involved with basinal water balance. In this paper, the term `nuclide` will be used when referring to a nuclear species that contains a particular number of protons and neutrons. The term is not specific to any element. The term `isotope` will be used to distinguish nuclear species of a given element (atoms with the same number of protons). That is to say, there are many nuclides in nature - for example, {sup 36}Cl, {sup 87}Sr, {sup 238}U; the element has four naturally-occurring isotopes - {sup 87}Sr, and {sup 88}Sr. This paper will first discuss the general principles that underlie the study of lithogenic and cosmogenic nuclides in hydrology, and provide references to some of the more important studies applying these principles and nuclides. We then turn in the second section to a discussion of their specific applications in catchment- scale systems. The final section of this paper discusses new directions in the application of lithogenic and cosmogenic nuclides to catchment hydrology, with some thoughts concerning possible applications that still remain unexplored.

  3. Attributes for NHDPlus Catchments (Version 1.1): Basin Characteristics, 2002

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set represents basin characteristics, compiled for every catchment in NHDPlus for the conterminous United States. These characteristics are basin shape...

  4. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Bedrock Geology

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents the area of bedrock geology types in square meters compiled for every catchment of MRB_E2RF1 catchments for Major River Basins...

  5. The "Teflon basin" myth: Snow-soil interactions in mountain catchments in the western US

    Science.gov (United States)

    Williams, M. W.; Cowie, R. M.

    2015-12-01

    In much of western North America, snow and snowmelt provide the primary means for storage of winter precipitation, effectively transferring water from the relatively wet winter season to the typically dry summers. A common assumption is that high-elevation catchments in the western United States behave like "Teflon basins" and that water released from seasonal storage in snow packs flows directly into streams with little or no interaction with underlying soils. Here I present information from a variety of catchments in the Colorado Front Range on snowmelt/soil interactions using isotopic, geochemical, nutrient and hydrometric data in 2- and 3- component hydrograph separations, along with end-member mixing analysis (EMMA). For most catchments we measured these parameters in weekly precipitation, the seasonal snowpack, snowmelt before contact with the ground, discharge, springs, soil solution, and groundwater. We ran EMMA at the catchment scale for catchments that represent the rain-snow transition zone in the montane forest, the seasonally snow covered sub-alpine to alpine transition zone, and a high-elevation alpine zone near the continental divide. In all catchments three end-members were the source waters for about 95% of discharge. Two end-members were the same in all catchments, snow and groundwater. For the alpine catchment talus springs was the third water source, while rain was the third water source in the two lower-elevation catchments. For all three catchments, soil solution plotted with stream waters along or near a line connecting the snow and groundwater end-members. Thus, for seasonally snow-covered catchments from montane to alpine ecosystems, snowmelt infiltrates underlying soils before snowmelt recharges groundwater reservoirs and contributes to surface flows. Seasonally snow-covered catchments are not Teflon basins. Rather, snowmelt infiltrates soils where solute concentrations are changed by biological and geochemical processes.

  6. Understanding Catchment Processes and Hydrological Modelling in the Abay/Upper Blue Nile Basin, Ethiopia

    OpenAIRE

    Gebrekristos, S.T.

    2015-01-01

    The water resources in the Abay/Upper Blue Nile basin are the source of life for the several hundred million people living in the basin and further downstream. It provides more than 60% of the total Nile water. Intensive farming in unfavourable soils and slopes, overgrazing and soil erosion is among the major problems in the basin. Land degradation as a result of soil erosion decreases soil fertility in the upper catchments and simultaneously increases sedimentation in reservoirs and irrigati...

  7. Carrying away and redistribution of radioisotopes on the Peyne catchment basin. Preliminary report

    International Nuclear Information System (INIS)

    The transfers of radioisotopes present in soils and sediments are essentially conditioned by the mobilities of the physical vectors which constitute their supports. The water is the main vector of natural transfer, radioisotopes being associated with it under dissolved or particulate shape. The rainout and the hydrous erosion are responsible in particular for the carrying away and for the redistribution of contaminants following an atmospheric deposit on a catchment basin. However their effect is not the same in any point of the catchment basin. The work begun here aims at elaborating a classification of the grounds sensitivity towards this phenomenon of radioisotopes carrying away. The different factors of sensitivity have been identified: pluviometry, slope, soils occupation and soils nature. The Peyne catchment basin, that presents an important variability of these four parameters, constitutes the experimental site for this study. On this catchment basin, we search to identify the areas the most sensitive to the carrying away of radioisotopes, by combining a theoretical predictive approach based on the cartography and a descriptive approach basing on the sampling and the analysis of soils samples. (N.C.)

  8. A Framework for Integrated Management of Transboundary Basins: the case of Sio sub-catchment in East Africa.

    OpenAIRE

    Obando, Joy A.; Makalle, Albinus; Bamutaze, Bamutaze

    2007-01-01

    The Sio sub-catchment is transboundary, originating in Kenya and flowing into Berkeley Bay of the Lake Victoria basin. It forms an important sub-catchment of the Nile basin and a significant base for the livelihood of small scale farmers engaged in mixed farming, depending on agriculture and livestock keeping as well as a large population depending on fishing. Indeed, high population densities exceeding 300 persons per square kilometre and cattle densities of 38 have been noted within basin, ...

  9. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Surficial Geology

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents the area of surficial geology types in square meters compiled for every MRB_E2RF1 catchment of selected Major River Basins (MRBs,...

  10. Attributes for NHDPlus Catchments (Version 1.1): Basin Characteristics, 2002

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents basin characteristics, compiled for every catchment in NHDPlus for the conterminous United States. These characteristics are basin shape index, stream density, sinuosity, mean elevation, mean slope, and number of road-stream crossings. The source data sets are the U.S. Environmental Protection Agency's NHDPlus and the U.S. Census Bureau's TIGER/Line Files. The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris

  11. Nonstationarities in Catchment Response According to Basin and Rainfall Characteristics: Application to Korean Watershed

    Science.gov (United States)

    Kwon, Hyun-Han; Kim, Jin-Guk; Jung, Il-Won

    2015-04-01

    It must be acknowledged that application of rainfall-runoff models to simulate rainfall-runoff processes are successful in gauged watershed. However, there still remain some issues that will need to be further discussed. In particular, the quantitive representation of nonstationarity issue in basin response (e.g. concentration time, storage coefficient and roughness) along with ungauged watershed needs to be studied. In this regard, this study aims to investigate nonstationarity in basin response so as to potentially provide useful information in simulating runoff processes in ungauged watershed. For this purpose, HEC-1 rainfall-runoff model was mainly utilized. In addition, this study combined HEC-1 model with Bayesian statistical model to estimate uncertainty of the parameters which is called Bayesian HEC-1 (BHEC-1). The proposed rainfall-runofall model is applied to various catchments along with various rainfall patterns to understand nonstationarities in catchment response. Further discussion about the nonstationarity in catchment response and possible regionalization of the parameters for ungauged watershed are discussed. KEYWORDS: Nonstationary, Catchment response, Uncertainty, Bayesian Acknowledgement This research was supported by a Grant (13SCIPA01) from Smart Civil Infrastructure Research Program funded by the Ministry of Land, Infrastructure and Transport (MOLIT) of Korea government and the Korea Agency for Infrastructure Technology Advancement (KAIA).

  12. Evaluation of water and energy balances ovet the Colombian Orinoco Catchment Basin

    Science.gov (United States)

    Abril, C.; Baquero-Bernal, A.

    2012-04-01

    This study presents a comparison between in-situ observations and gridded data from reanalyses and from a regional climate model over the Colombian Orinoco Catchment Basin, in South America, with focus on the surface water and energy balances. We use datasets from the regional climate model REMO and re-analyses ERA40, ERAInterim and NCEP/NCAR. The in-situ observations have been provided by the Colombian Institute of Hydrology, Meteorology and Environmental Studies (IDEAM). The balances are for the 1958-2011 period. Statistical analyses of temperature and precipitation are also presented. Discrepancies between gridded datasets and observations are evaluated and possible sources of error in each of the datasets are discussed. The research presented is the first intercomparison of the surface water and energy balances over the Colombian Orinoco Catchment Basin from different datasets.

  13. Spatial moments of catchment rainfall: rainfall spatial organisation, basin morphology, and flood response

    Directory of Open Access Journals (Sweden)

    D. Zoccatelli

    2011-12-01

    Full Text Available This paper describes a set of spatial rainfall statistics (termed "spatial moments of catchment rainfall" quantifying the dependence existing between spatial rainfall organisation, basin morphology and runoff response. These statistics describe the spatial rainfall organisation in terms of concentration and dispersion statistics as a function of the distance measured along the flow routing coordinate. The introduction of these statistics permits derivation of a simple relationship for the quantification of catchment-scale storm velocity. The concept of the catchment-scale storm velocity takes into account the role of relative catchment orientation and morphology with respect to storm motion and kinematics. The paper illustrates the derivation of the statistics from an analytical framework recently proposed in literature and explains the conceptual meaning of the statistics by applying them to five extreme flash floods occurred in various European regions in the period 2002–2007. High resolution radar rainfall fields and a distributed hydrologic model are employed to examine how effective are these statistics in describing the degree of spatial rainfall organisation which is important for runoff modelling. This is obtained by quantifying the effects of neglecting the spatial rainfall variability on flood modelling, with a focus on runoff timing. The size of the study catchments ranges between 36 to 982 km2. The analysis reported here shows that the spatial moments of catchment rainfall can be effectively employed to isolate and describe the features of rainfall spatial organization which have significant impact on runoff simulation. These statistics provide useful information on what space-time scales rainfall has to be monitored, given certain catchment and flood characteristics, and what are the effects of space-time aggregation on flood response modeling.

  14. An appraisal of precipitation distribution in the high-altitude catchments of the Indus basin

    OpenAIRE

    Dahri, Z.H.; Ludwig, F.; E. Moors; Ahmad, B.; A. Khan; P. Kabat

    2016-01-01

    Scarcity of in-situ observations coupled with high orographic influences has prevented a comprehensive assessment of precipitation distribution in the high-altitude catchments of Indus basin. Available data are generally fragmented and scattered with different organizations and mostly cover the valleys. Here, we combine most of the available station data with the indirect precipitation estimates the accumulation zones of major glaciers to analyse altitudinal dependency of precipitation in the...

  15. Variability of rainfall over Lake Kariba catchment area in the Zambezi river basin, Zimbabwe

    Science.gov (United States)

    Muchuru, Shepherd; Botai, Joel O.; Botai, Christina M.; Landman, Willem A.; Adeola, Abiodun M.

    2016-04-01

    In this study, average monthly and annual rainfall totals recorded for the period 1970 to 2010 from a network of 13 stations across the Lake Kariba catchment area of the Zambezi river basin were analyzed in order to characterize the spatial-temporal variability of rainfall across the catchment area. In the analysis, the data were subjected to intervention and homogeneity analysis using the Cumulative Summation (CUSUM) technique and step change analysis using rank-sum test. Furthermore, rainfall variability was characterized by trend analysis using the non-parametric Mann-Kendall statistic. Additionally, the rainfall series were decomposed and the spectral characteristics derived using Cross Wavelet Transform (CWT) and Wavelet Coherence (WC) analysis. The advantage of using the wavelet-based parameters is that they vary in time and can therefore be used to quantitatively detect time-scale-dependent correlations and phase shifts between rainfall time series at various localized time-frequency scales. The annual and seasonal rainfall series were homogeneous and demonstrated no apparent significant shifts. According to the inhomogeneity classification, the rainfall series recorded across the Lake Kariba catchment area belonged to category A (useful) and B (doubtful), i.e., there were zero to one and two absolute tests rejecting the null hypothesis (at 5 % significance level), respectively. Lastly, the long-term variability of the rainfall series across the Lake Kariba catchment area exhibited non-significant positive and negative trends with coherent oscillatory modes that are constantly locked in phase in the Morlet wavelet space.

  16. Catchment Restoration in the Tweed UNESCO-IHP HELP Basin - Eddleston Water

    Science.gov (United States)

    Spray, Christopher

    2013-04-01

    The EU Water Frame Work Directive (WFD) requires member states to work towards the achievement of 'good ecological status' for water bodies, through a 6 year cycle of river basin management plans (RBMPs). Within these RBMPs, states must develop and implement programmes of measures designed to improve the quality of individual water bodies at risk of failing to achieve this status. These RBMPS must not only be focussed on the key causes of failure, but increasingly look to deliver multiple benefits, such as flood risk reduction and improvement to biodiversity from such catchment interventions, and to involve communities and other stakeholders in restoration of their local environment. This paper reports on progress of a detailed study of the restoration of the Eddleston Water, a typical 'failing' water body in Scotland, the monitoring and governance arrangements behind this, and implications for rehabilitation of river systems elsewhere. Within UK rivers, the main causes of failure to achieve good ecological status are historical morphological changes to river courses, diffuse agricultural pollution and invasive non-native species. The Eddleston Water is a 70 sq kms sub-catchment of the Tweed, an UNESCO IHP-HELP basin in the Scottish : English borders, and is currently classified as 'bad' status, due largely to morphological changes to the course and structure of the river over the past 200 years. The main challenge therefor is physical restoration of the river to achieve functional connectivity with the flood plain. At the same time however, the two communities within the catchment suffer from flooding, so a second priority is to intervene within the catchment to reduce the risk of flooding through the use of "natural flood management" measures and, underlying both these two aspects a whole catchment approach to community participation and the achievement of a range of other ecosystem service benefits, including conservation of biodiversity. We report on the

  17. Streamflow response to climate variability and human activities in the upper catchment of the Yellow River Basin

    Institute of Scientific and Technical Information of China (English)

    ZHAO FangFang; XU ZongXue; ZHANG Lu; ZUO DePeng

    2009-01-01

    Both sensitivity-based method and simulation method are used to analyze the streamflow response to climate variability and human activities in the upper catchment of the Yellow River Basin (UYRB) in this study.The separation regime of effects from climate variability and human activities is investigated.Results show that the changes of streamflow are more sensitive to precipitation than potential evapotranspiration (PET).Effect of climate variability on streamflow estimated using the sensitiv-ity-based method is weak in the upper catchment of Jimai station, and strong in the upper catchment of Lanzhou station, where the climate effects accounted for about 50% of total streamflow changes.Effects of human activities on streamflow accounted for about 40% in the UYRB, with weaker effects in the upper catchment of Tangnaihai station than those in the upper catchment of Lanzhou station.Both climate variability and human activities are main factors to affect the changes of streamflow in the UYRB.

  18. Streamflow response to climate variability and human activities in the upper catchment of the Yellow River Basin

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Both sensitivity-based method and simulation method are used to analyze the streamflow response to climate variability and human activities in the upper catchment of the Yellow River Basin (UYRB) in this study. The separation regime of effects from climate variability and human activities is investigated. Results show that the changes of streamflow are more sensitive to precipitation than potential evapotranspiration (PET). Effect of climate variability on streamflow estimated using the sensitivity-based method is weak in the upper catchment of Jimai station, and strong in the upper catchment of Lanzhou station, where the climate effects accounted for about 50% of total streamflow changes. Effects of human activities on streamflow accounted for about 40% in the UYRB, with weaker effects in the upper catchment of Tangnaihai station than those in the upper catchment of Lanzhou station. Both climate variability and human activities are main factors to affect the changes of streamflow in the UYRB.

  19. An appraisal of precipitation distribution in the high-altitude catchments of the Indus basin.

    Science.gov (United States)

    Dahri, Zakir Hussain; Ludwig, Fulco; Moors, Eddy; Ahmad, Bashir; Khan, Asif; Kabat, Pavel

    2016-04-01

    Scarcity of in-situ observations coupled with high orographic influences has prevented a comprehensive assessment of precipitation distribution in the high-altitude catchments of Indus basin. Available data are generally fragmented and scattered with different organizations and mostly cover the valleys. Here, we combine most of the available station data with the indirect precipitation estimates at the accumulation zones of major glaciers to analyse altitudinal dependency of precipitation in the high-altitude Indus basin. The available observations signified the importance of orography in each sub-hydrological basin but could not infer an accurate distribution of precipitation with altitude. We used Kriging with External Drift (KED) interpolation scheme with elevation as a predictor to appraise spatiotemporal distribution of mean monthly, seasonal and annual precipitation for the period of 1998-2012. The KED-based annual precipitation estimates are verified by the corresponding basin-wide observed specific runoffs, which show good agreement. In contrast to earlier studies, our estimates reveal substantially higher precipitation in most of the sub-basins indicating two distinct rainfall maxima; 1st along southern and lower most slopes of Chenab, Jhelum, Indus main and Swat basins, and 2nd around north-west corner of Shyok basin in the central Karakoram. The study demonstrated that the selected gridded precipitation products covering this region are prone to significant errors. In terms of quantitative estimates, ERA-Interim is relatively close to the observations followed by WFDEI and TRMM, while APHRODITE gives highly underestimated precipitation estimates in the study area. Basin-wide seasonal and annual correction factors introduced for each gridded dataset can be useful for lumped hydrological modelling studies, while the estimated precipitation distribution can serve as a basis for bias correction of any gridded precipitation products for the study area. PMID

  20. Estimation of Catchment Transit Time in Fuji River Basin by using an improved Tank model

    Science.gov (United States)

    Wenchao, M.; Yamanaka, T.; Wakiyama, Y.; Wang, P.

    2013-12-01

    As an important parameter that reflects the characteristics of catchments, the catchment transit time (CTT) has been given much more widely attentions especially in recent years. The CTT is defined as the time water spends travelling through a catchment to the stream network [1], and it describes how catchments retain and release water and solutes and thus control geochemical and biogeochemical cycling and contamination persistence [2]. The objectives of the present study are to develop a new approach for estimating CTT without prior information on such TTD functions and to apply it to the Fuji River basin in the Central Japan Alps Region. In this study, an improved Tank model was used to compute mean CTT and TTD functions simultaneously. It involved water fluxes and isotope mass balance. Water storage capacity in the catchment, which strongly affects CTT, is reflected in isotope mass balance more sensitively than in water fluxes. A model calibrated with observed discharge and isotope data is used for virtual age tracer computation to estimate CTT. This model does not only consider the hydrological data and physical process of the research area but also reflects the actual TTD with considering the geological condition, land use and the other catchment-hydrological conditions. For the calibration of the model, we used river discharge record obtained by the Ministry of Land, Infrastructure and Transportation, and are collecting isotope data of precipitation and river waters monthly or semi-weekly. Three sub-catchments (SC1~SC3) in the Fuji River basin was selected to test the model with five layers: the surface layer, upper-soil layer, lower-soil layer, groundwater aquifer layer and bedrock layer (Layer 1- Layer 5). The evaluation of the model output was assessed using Nash-Sutcliffe efficiency (NSE), root mean square error-observations standard deviation ratio (RSR), and percent bias (PBIAS). Using long time-series of discharge records for calibration, the simulated

  1. Implementing Integrated Catchment Management in the upper Limpopo River basin: A situational assessment

    Science.gov (United States)

    Mwenge Kahinda, J.; Meissner, R.; Engelbrecht, F. A.

    2016-06-01

    A three-phase study was initiated as a way to promote Integrated Catchment Management approaches in the Limpopo River basin. This paper presents the situational assessment, which should enable De Beers to understand how their Venetia Mine operations are located within a broader and highly dynamic socio-economic and ecohydrological landscape as it pertains to water risks. The second phase, Risk assessment, aims to develop conservation interventions in the identified areas; the third phase will develop mechanisms for implementing water stewardship schemes to mitigate the shared water risks. Analysis of the social-ecological system (hydrological, climatic, ecological, socio-economic and governance systems) of the Limpopo River basin indicates that the institutional arrangement of the Limpopo River basin is neither simple nor effective. The basin is rapidly approaching closure in the sense that almost all of the available supplies of water have already been allocated to existing water users. If the proposed ecological flow requirements were to be met for all of the tributaries, the basin would be 'closed'. On-going and projected land use changes and water resources developments in the upper reaches of the basin, coupled with projected rainfall reductions and temperature increases, and allocation of the flows for the ecological reserve, are likely to further reduce downstream river flows. The coupled increase in temperature and decrease in rainfall is of great concern for everyone in the basin, especially the poorer communities, who rely on rain-fed agriculture for their livelihoods. Increased temperatures also lead to increased evaporation from reservoirs and therefore result in a decrease in water availability. This will lead to increased abstraction of groundwater, especially from alluvial aquifers, and consequently an increase in river transmission losses and a decrease in river flows.

  2. Monitoring of metals, organic compounds and coliforms in water catchment points from the Sinos River basin.

    Science.gov (United States)

    Nascimento, C A; Staggemeier, R; Bianchi, E; Rodrigues, M T; Fabres, R; Soliman, M C; Bortoluzzi, M; Luz, R B; Heinzelmann, L S; Santos, E L; Fleck, J D; Spilki, F R

    2015-05-01

    Unplanned use and occupation of the land without respecting its capacity of assimilation and environmental purification leads to the degradation of the environment and of water used for human consumption. Agricultural areas, industrial plants and urban centres developed without planning and the control of effluent discharges are the main causes of water pollution in river basins that receive all the liquid effluents produced in those places. Over the last decades, environmental management has become part of governmental agendas in search of solutions for the preservation of water quality and the restoration of already degraded resources. This study evaluated the conditions of the main watercourse of the Sinos River basin by monitoring the main physical, chemical and microbiological parameters described in the CONAMA Resolution no. 357/2005.The set of parameters evaluated at five catchment points of water human consumption revealed a river that has different characteristics in each reach, as the upper reach was class 1, whereas the middle and lower reaches of the basin were class 4. Monitoring pointed to households as the main sources of pollutants in those reaches, although metals used in the industrial production of the region were found in the samples analyzed. PMID:26270213

  3. The 20th century whole-basin trophic history of an inter-drumlin lake in an agricultural catchment.

    Science.gov (United States)

    Jordan, Philip; Rippey, Brian; Anderson, N John

    2002-10-01

    Eight 1-m sediment cores were extracted from across the basin of Friary Lough, a 5.4-ha eutrophic lake in a wholly grassland agricultural catchment in Co. Tyrone, Northern Ireland. Sedimentary TP, diatom inferred TP, Ca, Na, Fe, Mn, loss-on-ignition (LOI), dry weight and density were determined in the core profiles. Core dating and correlation gave a 210Pb, 137Cs and 241Am chronology from 1906 to 1995 and enabled a whole-basin estimate of chemical and sediment accumulation rate over the 20th Century. The major changes for all parameters occurred after c. 1946. Sediment accumulation rate was most influenced by organic matter accumulations, probably of planktonic origin, and increasing after c. 1946. Inorganic sediment accumulation rate was found to be largely unchanging through the century at 10 t km(-2) yr(-1) when expressed as catchment exports. All chemical accumulation rate changes occurred after c. 1946. Total phosphorus accumulation rate, however, was found to be the only chemical to be increasing throughout the epilimnion and hypolimnion areas of the sedimentary basin at an average of 22.5 mg m(-2) yr(-1) between 1946 and 1995. The other chemical parameters showed increasing accumulation rates after c. 1946 in the epilimnion part of the basin only. Interpreted in terms of whole-basin sedimentation and catchment export processes over time, it is suggested that diffuse TP inputs are independent of sediment inputs. This corresponds to hydrochemical models that suggest soluble P as the primary fraction that is lost from grassland catchments. The increase in sedimentary TP accumulation rate, and DI-TP concentration, are also explained with regard to current models that suggest increases in runoff P concentrations from elevated soil P concentrations. Increases in eplimnion chemical and sediment accumulation rate after c. 1946 may be due to local erosion that has limited impact on lake basin sedimentation. PMID:12389788

  4. Data mining methods for predicting event runoff coefficients in ungauged basins using static and dynamic catchment characteristics

    Science.gov (United States)

    Loritz, Ralf; Weiler, Markus; Seibert, Simon

    2015-04-01

    Transferring hydrological information into ungauged basin by regionalisation approaches is an ongoing field of research. Usually regionalisation techniques use physical landscape descriptors to transfer either model parameters or hydrological characteristics from a catchment to another. A common problem of these approaches is the high degree of uncertainty associated to their results. One reason is that often solely static (structural) catchment characteristics such as catchment area, physiographic properties or land use data are used for regionalisation. However, it is well known that the hydrological response of a 'natural' system is a complex and a non-linear interaction of its structure, state and forcing. Here it is important to note, that only structure is a static property. State and forcing are highly dynamic when considering the temporal and spatial scale of a rainfall-runoff event. To overcome the limitations associated with 'static' regionalisation techniques we propose a regionalisation technique for event runoff coefficients combining static and dynamic catchment properties. The approach is based on the two data mining algorithms 'random forests' and 'quantile regression forests'. The static catchment characteristics include standard variables such as physiographic properties, land cover and soil data. The dynamic variables include event based properties of the forcing (i.e. rainfall amount, intensity,...) and proxies for the initial state of the catchment (i.e. initial soil moisture). Together with the runoff coefficient these quantities were extracted form hydro-meteorological time series (precipitation, discharge and soil moisture) using an automated rainfall-runoff event detection technique. We tested our method using a set of 60 meso-scale catchments (3.1 to 205,6 km2, covering a range of different geologies and land uses) from Southwest Germany. We randomly separated the catchments in two groups. The first group (30 donor catchments) was used to

  5. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Base-Flow Index, 2002

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents the mean base-flow index expressed as a percent, compiled for every catchment of MRB_E2RF1 catchments of Major River Basins (MRBs,...

  6. Attributes for MRB_E2RF1 Catchments in Selected Major River Basins of the Conterminous United States: Contact Time, 2002

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents the average contact time, in units of days, compiled for every MRB_E2RF1 catchment of Major River Basins (MRBs, Crawford and...

  7. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: STATSGO Soil Characteristics

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents estimated soil variables compiled for every MRB_E2RF1 catchment of selected Major River Basins (MRBs, Crawford and others, 2006)....

  8. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Hydrologic Landscape Regions

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents the area of Hydrologic Landscape Regions (HLR) compiled for every MRB_E2RF1 catchment of the Major River Basins (MRBs, Crawford and...

  9. Relationship between catchment characteristics and forms of nitrogen in Cao-E River Basin, Eastern China

    Institute of Scientific and Technical Information of China (English)

    JIN Shuquan; LU Jun; CHEN Dingjiang; SHEN Yena; SHI Yiming

    2009-01-01

    The distribution of different nitrogen forms and their spatial and temporal variations in different pollution types of tributaries or reaches were investigated. Based on the catchments characteristics the tributaries or reaches can be classified into 4 types including headwater in mountainous areas (type I), agricultural non-point source (NPS) pollution in rural areas (type II), municipal and industrial pollution in urban areas (type III), and combined pollution in the main stream (type IV). Water samples were collected monthly from July 2003 to June 2006 in the Cao-E River basin in Zhejiang, Eastern China. The concentrations of NO3-N, NH4+-N, and total nitrogen (TN) were measured. The mean concentrations of NO3-N were in the order type IV > type II> type III > type I, whereas, NH4+-N, total organic nitrogen (TON), and TN were in the order type III > type IV > type II> type I. In headwater and rural reaches, CNO3-N was much higher than CNH4+-N. In urban reaches, TON and NH4+-N were the main forms, accounting for 54.7% and 32.1% of TN, respectively. In the whole river system, CNH4+-N decrease with increasing distance from cities, and CNO3-N increased with the increasing area of farmland in the catchments. With increased river flow, the CNO3-N increased and the CNH4+-N decreased in all types of reaches, while the variations of CTON and CTN were different. For TN, the concentration may be decreased with the increase of river flow, but the export load always increased.

  10. Plantation Forestry and Peak Flow Responses in Experimental Catchments and Large River Basins in Chile

    Science.gov (United States)

    Iroume, A.; Huber, A.

    2007-05-01

    Land use changes are inextricably linked to water resources and the consequences of such changes are a problem faced by water managers and governments across the world. This particular study considers the impact of changes in plantation forest cover on the hydrological response, with a specific focus on the issue of peak flow conditions and variation. The research still in progress is focused in small catchments and large river basins of Chile. The analysis of the data and the preparation of this document were carried out within the framework of the INCO- CT2004-510739 EPIC FORCE Project. EPIC FORCE aims to improve the integrated management of forest and water resources at the river basin scale through the development of policies based on sound science, focusing on extreme rainfall/snowmelt events. The focus areas are four Latin American countries (Costa Rica, Ecuador, Chile and Argentina.), which represent a range of humid forest and rainfall/snowmelt regimes with major flood and erosion problems and which suffer from a lack of integrated water and forest policies. Much of the controversy surrounding changes in peak flows following forest treatment arises from uncertainty over the response from different sizes of storms; whilst most studies agree that mean peak flow generally increases (even for only a short period) in the post harvesting period, there have been a number of different conclusions regarding influence of forest cover on peak flows from small storms compared with the flows from large events. In Chile, this research is been carried out in experimental catchments (less than 1 km2) and in large river basins (greater than 94 and up to 1,545 km2). Results from La Reina (34.4 ha), where peak flows from the pre-harvesting period (years 1997 to 1999, plantation of Pinus radiata established in 1977 covering the 79.5% of the area) were compared with those from the post- harvesting period (plantation clearcut between end of 1999 and first months of 2000 and

  11. Hydrological behaviour and water balance analysis for Xitiaoxi catchment of Taihu Basin

    OpenAIRE

    Li-juan XUE; Li-jiao LI; Zhang, Qi

    2008-01-01

    With the rapid social and economic development of the Taihu region, Taihu Lake now faces an increasingly severe eutrophication problem. Pollution from surrounding catchments contributes greatly to the eutrophication of water bodies in the region. Investigation of surface flow and associated mass transport for the Xitiaoxi catchment is of a significant degree of importance as the Xitiaoxi catchment is one of the major catchments within the Taihu region. A SWAT-based distributed hydrological mo...

  12. Attributes for MRB_E2RF1 Catchments in Selected Major River Basins: Population Density, 2000

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the average population density, in number of people per square kilometer multiplied by 10 for the year 2000, compiled for every MRB_E2RF1 catchment of selected Major River Basins (MRBs, Crawford and others, 2006). The source data set is the 2000 Population Density by Block Group for the Conterminous United States (Hitt, 2003). The MRB_E2RF1 catchments are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) RF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002; Brakebill and others, 2011). Data were compiled for every MRB_E2RF1 catchment for the conterminous United States covering covering New England and Mid-Atlantic (MRB1), South Atlantic-Gulf and Tennessee (MRB2), the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy (MRB3), the Missouri (MRB4), the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf (MRB5), the Rio Grande, Colorado, and the Great basin (MRB6), the Pacific Northwest (MRB7) river basins, and California (MRB8).

  13. Assessment of groundwater recharge and discharge in sub-catchments of Indus basin

    International Nuclear Information System (INIS)

    Groundwater discharge and recharge investigation was carried out in a selected sub-catchment of Indus Basin (Chashma Area) under an IAEA CRP. Sixteen sampling points were selected in the study area including fourteen groundwater and two canal water samples. Seven groundwater sampling points were selected in discharging area and the same numbers of sampling points were selected in recharging area. The first sampling campaign from discharging area was conducted in February 2011 and the second sampling campaign was carried out in March 2011. The electrical conductivity, toital dissolved salts, pH and temperature were measured in the field. The coordinates of the sampling points were recorded using GPS. All the collected samples were analyzed for stable isotopes (/sup 18/O, /sup 2/H). Plot of /sup 18/O vs. /sup 2/H values of surface water and groundwater along with the Global Meteoric Water Line (GMWL) is shown. /sup 18/O values of groundwater vary over a narrow range from -11.3 to -8.2% and /sup 2/H values vary from -76.3 to -53.8%. All groundwater samples except two shallow ones have highly depleted isotopic composition (close to the river/canal water). It means that these locations are recharged by the surface water. Two shallow groundwater samples show mixing of rain water with canal/river water. (orig./A.B.)

  14. Sulfonylurea herbicides in an agricultural catchment basin and its adjacent wetland in the St. Lawrence River basin.

    Science.gov (United States)

    de Lafontaine, Yves; Beauvais, Conrad; Cessna, Allan J; Gagnon, Pierre; Hudon, Christiane; Poissant, Laurier

    2014-05-01

    The use of sulfonylurea herbicides (SU) has increased greater than 100 times over the past 30 years in both Europe and North America. Applied at low rates, their presence, persistence and potential impacts on aquatic ecosystems remain poorly studied. During late-spring to early fall in 2009-2011, concentrations of 9 SU were assessed in two agricultural streams and their receiving wetland, an enlargement of the St. Lawrence River (Canada). Six SU in concentrations >LOQ (10 ng L(-1)) were detected in 10% or less of surface water samples. Rimsulfuron was detected each year, sulfosulfuron and nicosulfuron in two years and the others in one year only, suggesting that application of specific herbicides varied locally between years. Detection frequency and concentrations of SU were not significantly associated with total precipitation which occurred 1 to 5d before sampling. Concentrations and fate of SU differed among sites due to differences in stream dynamics and water quality characteristics. The persistence of SU in catchment basin streams reflected the dissipation effects associated with stream discharge. Maximum concentrations of some SU (223 and 148 ng L(-1)) were occasionally above the baseline level (100 ng L(-1)) for aquatic plant toxicity, implying potential toxic stress to flora in the streams. Substantially lower concentrations (max 55 ng L(-1)) of SU were noted at the downstream wetland site, likely as a result from dilution and mixing with St. Lawrence River water, and represent less toxicological risk to the wetland flora. Sporadic occurrence of SU at low concentrations in air and rain samples indicated that atmospheric deposition was not an important source of herbicides to the study area. PMID:24534695

  15. Chloride transport in a small catchment of the Norrström basin.

    OpenAIRE

    Dong, Mengni

    2014-01-01

    On a catchment scale, chloride (Cl-) leached from forest soil due to dry deposition and interaction between vegetation and soil could attribute to the Cl- mass balance. The availability of Cl- data from monitoring works enables the assessment of net ecosystem budgets of Cl-, which compares Cl- amount from wet deposition to that in stream export. Some studies have shown that Cl- imbalances could occur in some catchments and one of such catchments with negative budget is Kringlan. The Kringlan ...

  16. Geo-referenced modelling of metal concentrations in river basins at the catchment scale

    Science.gov (United States)

    Hüffmeyer, N.; Berlekamp, J.; Klasmeier, J.

    2009-04-01

    1. Introduction The European Water Framework Directive demands the good ecological and chemical state of surface waters [1]. This implies the reduction of unwanted metal concentrations in surface waters. To define reasonable environmental target values and to develop promising mitigation strategies a detailed exposure assessment is required. This includes the identification of emission sources and the evaluation of their effect on local and regional surface water concentrations. Point source emissions via municipal or industrial wastewater that collect metal loads from a wide variety of applications and products are important anthropogenic pathways into receiving waters. Natural background and historical influences from ore-mining activities may be another important factor. Non-point emissions occur via surface runoff and erosion from drained land area. Besides deposition metals can be deposited by fertilizer application or the use of metal products such as wires or metal fences. Surface water concentrations vary according to the emission strength of sources located nearby and upstream of the considered location. A direct link between specific emission sources and pathways on the one hand and observed concentrations can hardly be established by monitoring alone. Geo-referenced models such as GREAT-ER (Geo-referenced Regional Exposure Assessment Tool for European Rivers) deliver spatially resolved concentrations in a whole river basin and allow for evaluating the causal relationship between specific emissions and resulting concentrations. This study summarizes the results of investigations for the metals zinc and copper in three German catchments. 2. The model GREAT-ER The geo-referenced model GREAT-ER has originally been developed to simulate and assess chemical burden of European river systems from multiple emission sources [2]. Emission loads from private households and rainwater runoff are individually estimated based on average consumption figures, runoff rates

  17. Hydrological behaviour and water balance analysis for Xitiaoxi catchment of Taihu Basin

    Directory of Open Access Journals (Sweden)

    Li-juan XUE

    2008-09-01

    Full Text Available With the rapid social and economic development of the Taihu region, Taihu Lake now faces an increasingly severe eutrophication problem. Pollution from surrounding catchments contributes greatly to the eutrophication of water bodies in the region. Investigation of surface flow and associated mass transport for the Xitiaoxi catchment is of a significant degree of importance as the Xitiaoxi catchment is one of the major catchments within the Taihu region. A SWAT-based distributed hydrological model was established for the Xitiaoxi catchment. The model was calibrated and verified using hydrometeorological data from 1988 to 2001. The results indicate that the modeled daily and annual stream flow match the observed data both in the calibration period and the verification period, with a linear regression coefficient R2 and a coefficient e for modeled daily stream flow greater than 0.8 at Hengtangcun and Fanjiacun gauge stations. The results show that the runoff process in the Xitiaoxi catchment is affected both by rainfall and human activities (e.g., reservoirs and polder areas. Moreover, the human activities weaken flood peaks more noticeably during rainstorms. The water balance analysis reveals the percentages of precipitation made up by surface flow, evapotranspiration, groundwater recharge and the change of soil storage, all of which are considered useful to the further understanding of the hydrological processes in the Xitiaoxi catchment. This study provides a good base for further studies in mass transport modeling and comparison of modeling results from similar hydrological models.

  18. Hydrological behaviour and water balance analysis for Xitiaoxi catchment of Taihu Basin

    Institute of Scientific and Technical Information of China (English)

    Xue Lijuan; Li Lijiao; Zhang Qi

    2008-01-01

    With the rapid social and economic development of the Taihu region, Taihu Lake now faces an increasingly severe eutrophication problem. Pollution from surrounding catchments contributes greatly to the eutrophication of water bodies in the region. Investigation of surface flow and associated mass transport for the Xitiaoxi catchment is of a significant degree of importance as the Xitiaoxi catchment is one of the major catchments within the Taihu region. A SWAT-based distributed hydrological model was established for the Xitiaoxi catchment. The model was calibrated and verified using hydrometeorological data from 1988 to 2001. The results indicate that the modeled daily and annual stream flow match the observed data both in the calibration period and the verification period, with a linear regression coefficient R2 and a coefficient e for modeleddaily stream flow greater than 0.8 at Hengtangcun and Fanjiacun gauge stations. The results show that the runoffprocess in the Xitiaoxi catchment is affected both by rainfall and human activities (e.g., reservoirs and polder areas). Moreover, the human activities weaken flood peaks more noticeably during rainstorms. The water balance analysis reveals the percentages of precipitation made up by surface flow, evapotranspiration, groundwater recharge and the change of soil storage, all of which are considered useful to the further understanding of the hydrological processes in the Xitiaoxi catchment. This study provides a good base for further studies in mass transport modeling and comparison of modeling results from similar hydrological models.

  19. Changes in land cover, rainfall and stream flow in Upper Gilgel Abbay catchment, Blue Nile basin – Ethiopia

    Directory of Open Access Journals (Sweden)

    T. H. M. Rientjes

    2011-06-01

    Full Text Available In this study we evaluated changes in land cover and rainfall in the Upper Gilgel Abbay catchment in the Upper Blue Nile basin and how changes affected stream flow in terms of annual flow, high flows and low flows. Land cover change assessment was through classification analysis of remote sensing based land cover data while assessments on rainfall and stream flow data are by statistical analysis. Results of the supervised land cover classification analysis indicated that 50.9 % and 16.7 % of the catchment area was covered by forest in 1973 and 2001, respectively. This significant decrease in forest cover is mainly due to expansion of agricultural land.

    By use of a change detection procedure, three periods were identified for which changes in rainfall and stream flow were analyzed. Rainfall was analyzed at monthly base by use of the Mann-Kendall test statistic and results indicated a statistically significant, decreasing trend for most months of the year. However, for the wet season months of June, July and August rainfall has increased. In the period 1973–2005, the annual flow of the catchment decreased by 12.1 %. Low flow and high flow at daily base were analyzed by a low flow and a high flow index that is based on a 95 % and 5 % exceedance probability. Results of the low flow index indicated decreases of 18.1 % and 66.6 % for the periods 1982–2000 and 2001–2005 respectively. Results of high flows indicated an increase of 7.6 % and 46.6 % for the same periods. In this study it is concluded that over the period 1973–2005 stream flow has changed in the Gilgel Abbay catchment by changes in land cover and changes in rainfall.

  20. Hydrograph separation using 222Rn and stable isotopes estimations in four sub-catchments of the Attert basin (Luxembourg)

    International Nuclear Information System (INIS)

    Full text: In order to get informations about the hydrologic signature of small rivers during and after heavy rain events, four small catchments were selected as experimental sites. Hydrograph separations based on environmental tracers were performed. Natural isotopic tracers such as oxygen 18, Deuterium and particularly 222 Rn may help to distinguish the components dominating the outflow, particularly of 'pre-event waters', 'event waters' and 'post-event waters'. Even with moderate concentrations in groundwater, radon can be a very sensitive indicator of groundwater input into rivers. The selected sub-catchments under investigation are situated in the western part of Luxembourg and belong to the Attert basin, the latter being integrated in the European Network of Experimental Research Basins (ERB). Radon gas detectors were adapted to measure continuously the radon activity in water. These detectors are installed at chosen points at the basins outflows together with high precision thermometers, conductivity meters, flow meters and automatic water samplers for chemical analysis. Besides the continuous measurements, grab water samples were taken for radon measurements at different locations along a stream, most of them during periods of heavy rain events. A limited number of samples was also analysed for their content of radium and uranium and of the stable isotopes oxygen 18, Deuterium. Presented are results over a one year measurement campaign. During the dry season i.e. during more or less continuous discharge conditions, the observed values did not show substantial variations and could be used as reference values. The high fluctuations of the measured data during heavy rain events are discussed and the interplay of the different parameters analysed. The research is part of the national project 'CYCLEAU' based on the study of the interactions between different parameters in the water cycle, at several scales. The project CYCLEAU is supported by the FNR (National

  1. Hydrograph separation using 222Rn and stable isotopes estimations in four sub-catchments of the Attert basin (Luxembourg)

    International Nuclear Information System (INIS)

    Full text: In order to get informations about the hydrologic signature of small rivers during and after heavy rain events, four small catchments were selected as experimental sites. Hydrograph separations based on environmental tracers were performed. Natural isotopic tracers such as 18O, 2H and particularly 222Rn may help to distinguish the components dominating the outflow, particularly of 'pre-event waters', 'event waters' and 'post-event waters'. Even with moderate concentrations in groundwater, radon can be a very sensitive indicator of groundwater input into rivers. The selected sub-catchments under investigation are situated in the western part of Luxembourg and belong to the Attert basin, the latter being integrated in the European Network of Experimental Research Basins (ERB). Radon gas detectors were adapted to measure continuously the radon activity in water. These detectors are installed at chosen points at the basins outflows together with high precision thermometers, conductivity meters, flow meters and automatic water samplers for chemical analysis. Besides the continuous measurements, grab water samples were taken for radon measurements at different locations along a stream, most of them during periods of heavy rain events. A limited number of samples was also analysed for their content of radium and uranium and of the stable isotopes 18O and 2H. Presented are results over a one year measurement campaign. During the dry season i.e. during more or less continuous discharge conditions, the observed values did not show substantial variations and could be used as reference values. The high fluctuations of the measured data during heavy rain events are discussed and the interplay of the different parameters analysed. The research is part of the national project 'CYCLEAU' based on the study of the interactions between different parameters in the water cycle, at several scales. The project CYCLEAU is supported by the FNR (National Research Fund

  2. Validation of soil hydraulic pedotransfer functions at the local and catchment scale for an Indonesian basin

    Science.gov (United States)

    Booij, Martijn J.; Oldhoff, Ruben J. J.; Rustanto, Andry

    2016-04-01

    In order to accurately model the hydrological processes in a catchment, information on the soil hydraulic properties is of great importance. These data can be obtained by conducting field work, which is costly and time consuming, or by using pedotransfer functions (PTFs). A PTF is an empirical relationship between easily obtainable soil characteristics and a soil hydraulic parameter. In this study, PTFs for the saturated hydraulic conductivity (Ks) and the available water content (AWC) are investigated. PTFs are area-specific, since for instance tropical soils often have a different composition and hydraulic behaviour compared to temperate soils. Application of temperate soil PTFs on tropical soils might result in poor performance, which is a problem as few tropical soil PTFs are available. The objective of this study is to determine whether Ks and AWC can be accurately approximated using PTFs, by analysing their performance at both the local scale and the catchment scale. Four published PTFs for Ks and AWC are validated on a data set of 91 soil samples collected in the Upper Bengawan Solo catchment on Java, Indonesia. The AWC is predicted very poorly, with Nash-Sutcliffe Efficiency (NSE) values below zero for all selected PTFs. For Ks PTFs better results were found. The Wösten and Rosetta-3 PTFs predict the Ks moderately accurate, with NSE values of 0.28 and 0.39, respectively. New PTFs for both AWC and Ks were developed using multiple linear regression and NSE values of 0.37 (AWC) and 0.55 (Ks) were obtained. Although these values are not very high, they are significantly higher than for the published PTFs. The hydrological SWAT model was set up for the Keduang, a sub-catchment of the Upper Bengawan Solo River, to simulate monthly catchment streamflow. Eleven cases were defined to validate the PTFs at the catchment scale. For the Ks-PTF cases NSE values of around 0.84 were obtained for the validation period. The use of AWC PTFs resulted in slightly lower NSE

  3. Carrying away and redistribution of radioisotopes on the Peyne catchment basin. Preliminary report; Entrainement et redistribution des radionucleides sur le bassin versant de la Peyne. Rapport preliminaire

    Energy Technology Data Exchange (ETDEWEB)

    Duffa, C.; Danic, F

    2006-07-01

    The transfers of radioisotopes present in soils and sediments are essentially conditioned by the mobilities of the physical vectors which constitute their supports. The water is the main vector of natural transfer, radioisotopes being associated with it under dissolved or particulate shape. The rainout and the hydrous erosion are responsible in particular for the carrying away and for the redistribution of contaminants following an atmospheric deposit on a catchment basin. However their effect is not the same in any point of the catchment basin. The work begun here aims at elaborating a classification of the grounds sensitivity towards this phenomenon of radioisotopes carrying away. The different factors of sensitivity have been identified: pluviometry, slope, soils occupation and soils nature. The Peyne catchment basin, that presents an important variability of these four parameters, constitutes the experimental site for this study. On this catchment basin, we search to identify the areas the most sensitive to the carrying away of radioisotopes, by combining a theoretical predictive approach based on the cartography and a descriptive approach basing on the sampling and the analysis of soils samples. (N.C.)

  4. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Level 3 Nutrient Ecoregions, 2002

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents the area of each level 3 nutrient ecoregion in square meters compiled for every MRB_E2RF1 catchment of the Major River Basins...

  5. River water quality of the River Cherwell: an agricultural clay-dominated catchment in the upper Thames Basin, southeastern England.

    Science.gov (United States)

    Neal, Colin; Neal, Margaret; Hill, Linda; Wickham, Heather

    2006-05-01

    The water quality of the River Cherwell and a tributary of it, the Ray, are described in terms of point and diffuse sources of pollution, for this rural area of the upper Thames Basin. Point sources of pollution dominate at the critical ecological low flow periods of high biological activity. Although the surface geology is predominantly clay, base flow is partly supplied from springs in underlying carbonate-bearing strata, which influences the water quality particularly with regards to calcium and alkalinity. The hydrogeochemistry of the river is outlined and the overall importance of urban point sources even in what would normally be considered to be rural catchments is stressed in relation to the European Unions Water Framework Directive. Issues of phosphorus stripping at sewage treatment works are also considered: such stripping on the Cherwell has reduced phosphorus concentrations by about a factor of two, but this is insufficient for the needs of the Water Framework Directive. PMID:16253306

  6. Understanding Catchment Processes and Hydrological Modelling in the Abay/Upper Blue Nile Basin, Ethiopia

    NARCIS (Netherlands)

    Gebrekristos, S.T.

    2015-01-01

    The water resources in the Abay/Upper Blue Nile basin are the source of life for the several hundred million people living in the basin and further downstream. It provides more than 60% of the total Nile water. Intensive farming in unfavourable soils and slopes, overgrazing and soil erosion is among

  7. Understanding the emergence and functioning of river committees in a catchment of the Pangani basin, Tanzania

    OpenAIRE

    Hans C. Komakech; Pieter van der Zaag

    2011-01-01

    In this paper we explore the emergence and functioning of river committees (RCs) in Tanzania, which are local water management structures that allocate and solve water conflict between different water users (smallholder irrigators, large commercial farmers, municipalities, etc) along one river. The paper is based on empirical research of three committees in the Themi sub-catchment. The committees mostly emerged in response to drought-induced competition and conflict over water, rapid urbanisa...

  8. Response of Stream Pollution Characteristics to Catchment Land Cover in Cao-E River Basin, China

    Institute of Scientific and Technical Information of China (English)

    SHEN Ye-Na; L(U) Jun; CHEN Ding-Jiang; SHI Yi-Ming

    2011-01-01

    This study addressed the relationship of river water pollution characteristics to land covers and human activities in the catchments in a complete river system named Cao-E River in eastcrn China. Based on the hydrogsochemical data collected monthly over a period of 3 years, cluster analysis (CA) and principal component analysis (PCA) were adopted to categorize the river reaches and reveal their pollution characteristics. According to the differences of water quality in the river reaches and land use patterns and average population densities in their catchments, the whole river system could be categorized into three groups of river reaches, i.e., non-point sources pollution reaches (NPSPR), urban reaches (UR) and mixed sources pollution reaches (MSPR). In UR and MSPR, the water quality was mainly impacted by nutrient and organic pollution, while in NPSPR nutrient pollution was the main cause. The nitrate was the main nitrogen form in NPSPR and particulate phosphorus was the main phosphorus form in MSPR. There were no apparent trends for the variations of pollutant concentrations with increasing river flows in NPSPR and MSPR, while in UR the pollutant concentrations decreased with increasing river flows. Thus dry season was the critical period for water pollution control in UR. Therefore, catchment land covers and human activities had significant impact on river reach water pollution type, nutrient forms and water quality responses to hydrological conditions, which might be crucial for developing strategies to combat water pollution in watershed scale.

  9. Scenarios of changes of selected components of hydrosphere and biosphere in catchment basin of Hron River and Vah River as consequence of climatic change

    International Nuclear Information System (INIS)

    This text-book consist of the following parts: (1) Hydrologic and climatic relationship of catchment basins; (2) Space interpretation of outputs of climatic scenarios in catchment basins of Hron River and Vah River by geostatistical methods; (3) Teleconnection of annual overflows with SO, NAO, AO and QBO phenomenons; (4) Snow; (5) Mathematical model for modelling of influence of climatic changes on runoff processes; (6) Multi-linear model of transformation of runoff in river-basins; (7) Influence of climatic change on capacity utilization of reserve volume of water reservoir Orava River; (8) Quality of surface waters; (9) Influence of climatic changes on biological factors and soil hydrology; (10) Proposal of framing adaptation arrangements.

  10. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Average Atmospheric (Wet) Deposition of Inorganic Nitrogen, 2002

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This tabular data set represents the average atmospheric (wet) deposition, in kilograms per square kilometer, of inorganic nitrogen for the year 2002 compiled for every catchment for MRB_E2RF1 of Major River Basins (MRBs, Crawford and others, 2006). The source data set for wet deposition was from the USGS's raster data set atmospheric (wet) deposition of inorganic nitrogen for 2002 (Gronberg, 2005). The MRB_E2RF1 catchments are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) ERF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002; Brakebill and others, 2011). Data were compiled for every catchment of MRB_E2RF1 catchments for the conterminous United States covering New England and Mid-Atlantic (MRB1), South Atlantic-Gulf and Tennessee (MRB2), the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy (MRB3), the Missouri (MRB4), the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf (MRB5), the Rio Grande, Colorado, and the Great basin (MRB6), the Pacific Northwest (MRB7) river basins, and California (MRB8).

  11. Monitoring of sediments transport in the small catchment-basin contaminated with 137 Cs

    International Nuclear Information System (INIS)

    With the objective of evaluating the environmental impact due to the erosion, deposition and transport of pollutants in a small catchment (area of 16 km2), contaminated with 137 Cs, a monitoring program, which includes field work and lab analysis, was established. Basically, this program involves the collection of suspended and bed sediment samples in different sites of the catchment during the occurrence of moderate and extreme floods. The particle size distribution was determined through the analysis of the samples by Pipet (silt and clay) and Sieve (sand) method. The samples were also analyzed for concentrations of sediment and 137 Cs on sediment. In a general way, it was observed that the concentration of 137 Cs on sediment decreases linearly during the initial portion of the hydrographic, still decreasing during the peak occurrence and then increases during the final portion of the curve. A possible explanation for this behavior is that during the initial phase of each event, only the course particles (silt and sand), which have a lower adsorption capacity are transported. (author)

  12. Study of the dynamics of drainage of 137Cs present on the catchment basins of French rivers

    International Nuclear Information System (INIS)

    An operational model describing the drainage of radionuclides was selected from a bibliographical synthesis. This model supplies an expression of the dissolved flux in rivers according to the flow of the river and the activity deposited on the catchment basin. To adjust this model for 137Cs coming from the Chernobylsk accident and the main French rivers, series of data reporting the temporal evolution of the activity of 137Cs in the water are necessary.The difficulty inherent to the measure of this radionuclide in the water led to dread its activity through that, more easily measurable, sediments and water plants. Measures on these indicators, upstream to any release of industrial effluents, were notably realized since 1991 within the framework of the annual follow-up of French nuclear power plants. The model of drainage is thus adjusted essentially on these data within a multiplicative factor (this factor being Kd or Fc). This requires however some preliminary adaptations: Kd being dependent on granulometry characteristics of the sediments samples, a standardization of their activity on granulometry criteria must be made. For the aquatic plants, it is necessary to look for their time of answer before being able to adjust the model. The obtained results, on plants as on sediments, indicate that for the big French rivers, the activity of 137Cs in aquatic environment decreases since 1987 with a period from 4 to 7 years. If the level of contamination of every river depends on the average contamination of the catchment basin (average deposit in Bq by m2), it seems that this level is also influenced by the other parameters as the size of the catchment basin, even some characteristics of the drained soils. This part of the study remains to deepen. It joins the works led to the L.E.R.C.M. on the migration of radionuclides in soils. On the upstream part of the Rhone river, the aquatic plants indicate that the flow plays a role of dilution of the dissolved radioactivity

  13. SURFACE WATER POLLUTION WITH HEAVY METALS IN THE LOWER CATCHMENT OF JIU RIVER BASIN, ACCORDING TO THE WATER FRAMEWORK DIRECTIVE (2000/60/EC

    Directory of Open Access Journals (Sweden)

    ADINA SANDA ŞERBAN

    2011-03-01

    Full Text Available Surface water pollution with heavy metals in the lower catchment of Jiu river basin, according to the Water Framework Directive (2000/60/EC. The Water Framework Directive establishes a single transparent, effective and coherent water policy by defining a strategy to combat pollution by requiring specific action programs.Chemical pollution of surface water presents a threat to the aquatic environment with acute and chronic toxicity to aquatic organisms, accumulation in the ecosystem and losses of habitats and biodiversity, as well as a threat to human health (art.1 from Directive 2008/105/EC regarding the environmental quality standards for water policy.The purpose of this study is to evaluate the chemical status for surface water bodies in the lower catchment of Jiu river basin. The assessment was made taking into account the water impact of four heavy metals: cadmium (Cd, nickel (Ni, mercury (Hg and lead (Pb.

  14. SURFACE WATER POLLUTION WITH HEAVY METALS IN THE LOWER CATCHMENT OF JIU RIVER BASIN, ACCORDING TO THE WATER FRAMEWORK DIRECTIVE (2000/60/EC)

    OpenAIRE

    ADINA SANDA ŞERBAN

    2011-01-01

    Surface water pollution with heavy metals in the lower catchment of Jiu river basin, according to the Water Framework Directive (2000/60/EC). The Water Framework Directive establishes a single transparent, effective and coherent water policy by defining a strategy to combat pollution by requiring specific action programs.Chemical pollution of surface water presents a threat to the aquatic environment with acute and chronic toxicity to aquatic organisms, accumulation in the ecosystem and losse...

  15. Characterisation of stable isotopes to identify residence times and runoff components in two meso-scale catchments in the Abay/Upper Blue Nile basin, Ethiopia

    OpenAIRE

    Tekleab, S.; Wenninger, J.W.; S. Uhlenbrook

    2014-01-01

    Measurements of the stable isotopes oxygen-18 (18O) and deuterium (2H) were carried out in two meso-scale catchments, Chemoga (358 km2) and Jedeb (296 km2) south of Lake Tana, Abay/Upper Blue Nile basin, Ethiopia. The region is of paramount importance for the water resources in the Nile basin, as more than 70% of total Nile water flow originates from the Ethiopian highlands. Stable isotope compositions in precipitation, spring water and streamflow were analysed (i) to characterise the spatial...

  16. Characterisation of stable isotopes to identify residence times and runoff components in two meso-scale catchments in the Abay/Upper Blue Nile basin, Ethiopia

    OpenAIRE

    Tekleab, S.; Wenninger, J.; S. Uhlenbrook

    2014-01-01

    Measurements of the stable isotopes oxygen-18 (18O) and deuterium (2H) were carried out in two meso-scale catchments, Chemoga (358 km2) and Jedeb (296 km2) south of Lake Tana, Abay/Upper Blue Nile basin, Ethiopia. The region is of paramount importance for the water resources in the Nile basin, as more than 70% of total Nile water flow originates from the Ethiopian highlands. Stable isotope compositions in precipitation, spring water and streamflow were analysed (i) to charac...

  17. Post-wildfire recovery of water yield in the Sydney Basin water supply catchments: An assessment of the 2001/2002 wildfires

    Science.gov (United States)

    Heath, J. T.; Chafer, C. J.; van Ogtrop, F. F.; Bishop, T. F. A.

    2014-11-01

    Wildfire is a recurring event which has been acknowledged by the literature to impact the hydrological cycle of a catchment. Hence, wildfire may have a significant impact on water yield levels within a catchment. In Australia, studies of the effect of fire on water yield have been limited to obligate seeder vegetation communities. These communities regenerate from seed banks in the ground or within woody fruits and are generally activated by fire. In contrast, the Sydney Basin is dominated by obligate resprouter communities. These communities regenerate from fire resistant buds found on the plant and are generally found in regions where wildfire is a regular occurrence. The 2001/2002 wildfires in the Sydney Basin provided an opportunity to investigate the impacts of wildfire on water yield in a number of catchments dominated by obligate resprouting communities. The overall aim of this study was to investigate whether there was a difference in water yield post-wildfire. Four burnt subcatchments and 3 control subcatchments were assessed. A general additive model was calibrated using pre-wildfire data and then used to predict post-wildfire water yield using post-wildfire data. The model errors were analysed and it was found that the errors for all subcatchments showed similar trends for the post-wildfire period. This finding demonstrates that wildfires within the Sydney Basin have no significant medium-term impact on water yield.

  18. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Level 3 Ecoregions

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This tabular data set represents the estimated area of level 3 ecological landscape regions (ecoregions), as defined by Omernik (1987), compiled for every MRB_E2RF1 catchment of the Major River Basins (MRBs, Crawford and others, 2006). The source data set is Level III Ecoregions of the Continental United States (U.S. Environmental Protection Agency, 2003). The MRB_E2RF1 catchments are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) ERF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002; Brakebill and others, 2011). Data were compiled for every MRB_E2RF1 catchment for the conterminous United States covering New England and Mid-Atlantic (MRB1), South Atlantic-Gulf and Tennessee (MRB2), the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy (MRB3), the Missouri (MRB4), the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf (MRB5), the Rio Grande, Colorado, and the Great basin (MRB6), the Pacific Northwest (MRB7) river basins, and California (MRB8).

  19. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Level 3 Nutrient Ecoregions, 2002

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This tabular data set represents the area of each level 3 nutrient ecoregion in square meters compiled for every MRB_E2RF1 catchment of the Major River Basins (MRBs, Crawford and others, 2006). The source data are from the 2002 version of the U.S. Environmental Protection Agency's (USEPA) Aggregations of Level III Ecoregions for National Nutrient Assessment & Management Strategy (USEPA, 2002). The MRB_E2RF1 catchments are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) ERF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002; Brakebill and others, 2011). Data were compiled for every MRB_E2RF1 catchment for the conterminous United States covering New England and Mid-Atlantic (MRB1), South Atlantic-Gulf and Tennessee (MRB2), the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy (MRB3), the Missouri (MRB4), the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf (MRB5), the Rio Grande, Colorado, and the Great basin (MRB6), the Pacific Northwest (MRB7) river basins, and California (MRB8).

  20. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Normalized Atmospheric Deposition for 2002, Ammonium (NH4)

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This tabular data set represents the average normalized (wet) deposition, in kilograms per square kilometer multiplied by 100, of ammonium (NH4) for the year 2002 compiled for every MRB_E2RF1 catchment of the Major River Basins (MRBs, Crawford and others, 2006). Estimates of NH4 deposition are based on National Atmospheric Deposition Program (NADP) measurements (B. Larsen, U.S. Geological Survey, written. commun., 2007). De-trending methods applied to the year 2002 are described in Alexander and others, 2001. NADP site selection met the following criteria: stations must have records from 1995 to 2002 and have a minimum of 30 observations. The MRB_E2RF1 catchments are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) ERF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002; Brakebill and others, 2011). Data were compiled for every MRB_E2RF1 catchment for the conterminous United States covering New England and Mid-Atlantic (MRB1), South Atlantic-Gulf and Tennessee (MRB2), the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy (MRB3), the Missouri (MRB4), the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf (MRB5), the Rio Grande, Colorado, and the Great basin (MRB6), the Pacific Northwest (MRB7) river basins, and California (MRB8).

  1. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Normalized Atmospheric Deposition for 2002, Nitrate (NO3)

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This tabular data set represents the average normalized (wet) deposition, in kilograms per square kilometer multiplied by 100, of Nitrate (NO3) for the year 2002 compiled for every MRB_E2RF1 catchment of the Major River Basins (MRBs, Crawford and others, 2006). Estimates of NO3 deposition are based on National Atmospheric Deposition Program (NADP) measurements (B. Larsen, U.S. Geological Survey, written. commun., 2007). De-trending methods applied to the year 2002 are described in Alexander and others, 2001. NADP site selection met the following criteria: stations must have records from 1995 to 2002 and have a minimum of 30 observations. The MRB_E2RF1 catchments are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) ERF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002; Brakebill and others, 2011). Data were compiled for every MRB_E2RF1 catchment for the conterminous United States covering New England and Mid-Atlantic (MRB1), South Atlantic-Gulf and Tennessee (MRB2), the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy (MRB3), the Missouri (MRB4), the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf (MRB5), the Rio Grande, Colorado, and the Great basin (MRB6), the Pacific Northwest (MRB7) river basins, and California (MRB8).

  2. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Normalized Atmospheric Deposition for 2002, Total Inorganic Nitrogen

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This tabular data set represents the average normalized atmospheric (wet) deposition, in kilograms per square kilometer multiplied by 100, of Total Inorganic Nitrogen for the year 2002 compiled for every MRB_E2RF1 catchment of selected Major River Basins (MRBs, Crawford and others, 2006). Estimates of Total Inorganic Nitrogen deposition are based on National Atmospheric Deposition Program (NADP) measurements (B. Larsen, U.S. Geological Survey, written. commun., 2007). De-trending methods applied to the year 2002 are described in Alexander and others, 2001. NADP site selection met the following criteria: stations must have records from 1995 to 2002 and have a minimum of 30 observations. The MRB_E2RF1 catchments are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) ERF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002; Brakebill and others, 2011). Data were compiled for every MRB_E2RF1 catchment for the conterminous United States covering New England and Mid-Atlantic (MRB1), South Atlantic-Gulf and Tennessee (MRB2), the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy (MRB3), the Missouri (MRB4), the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf (MRB5), the Rio Grande, Colorado, and the Great basin (MRB6), the Pacific Northwest (MRB7) river basins, and California (MRB8).

  3. Characterisation of stable isotopes to identify residence times and runoff components in two meso-scale catchments in the Abay/Upper Blue Nile basin, Ethiopia

    Science.gov (United States)

    Tekleab, S.; Wenninger, J.; Uhlenbrook, S.

    2014-06-01

    Measurements of the stable isotopes oxygen-18 (18O) and deuterium (2H) were carried out in two meso-scale catchments, Chemoga (358 km2) and Jedeb (296 km2) south of Lake Tana, Abay/Upper Blue Nile basin, Ethiopia. The region is of paramount importance for the water resources in the Nile basin, as more than 70% of total Nile water flow originates from the Ethiopian highlands. Stable isotope compositions in precipitation, spring water and streamflow were analysed (i) to characterise the spatial and temporal variations of water fluxes; (ii) to estimate the mean residence time of water using a sine wave regression approach; and (iii) to identify runoff components using classical two-component hydrograph separations on a seasonal timescale. The results show that the isotopic composition of precipitation exhibits marked seasonal variations, which suggests different sources of moisture generation for the rainfall in the study area. The Atlantic-Indian Ocean, Congo basin, Upper White Nile and the Sudd swamps are the potential moisture source areas during the main rainy (summer) season, while the Indian-Arabian and Mediterranean Sea moisture source areas during little rain (spring) and dry (winter) seasons. The spatial variation in the isotopic composition is influenced by the amount effect as depicted by moderate coefficients of determination on a monthly timescale (R2 varies from 0.38 to 0.68) and weak regression coefficients (R2 varies from 0.18 to 0.58) for the altitude and temperature effects. A mean altitude effect accounting for -0.12‰/100 m for 18O and -0.58‰/100 m for 2H was discernible in precipitation isotope composition. Results from the hydrograph separation on a seasonal timescale indicate the dominance of event water, with an average of 71 and 64% of the total runoff during the wet season in the Chemoga and Jedeb catchments, respectively. Moreover, the stable isotope compositions of streamflow samples were damped compared to the input function of

  4. Quantitative catchment profiling to apportion faecal indicator organism budgets for the Ribble system, the UK's sentinel drainage basin for Water Framework Directive research.

    Science.gov (United States)

    Stapleton, C M; Wyer, M D; Crowther, J; McDonald, A T; Kay, D; Greaves, J; Wither, A; Watkins, J; Francis, C; Humphrey, N; Bradford, M

    2008-06-01

    Under the EU Water Framework Directive (WFD) 20/60/EC and the US Federal Water Pollution Control Act 2002 management of water quality within river drainage basins has shifted from traditional point-source control to a holistic approach whereby the overall contribution of point and diffuse sources of pollutants has to be considered. Consequently, there is a requirement to undertake source-apportionment studies of pollutant fluxes within catchments. The inclusion of the Bathing Water Directive (BWD), under the list of 'protected areas' in the WFD places a requirement to control sources of faecal indicator organisms within catchments in order to achieve the objectives of both the BWD (and its revision - 2006/7/EC) and the WFD. This study was therefore initiated to quantify catchment-derived fluxes of faecal indicator compliance parameters originating from both point and diffuse sources. The Ribble drainage basin is the single UK sentinel WFD research catchment and discharges to the south of the Fylde coast, which includes a number of high profile, historically non-compliant, bathing waters. Faecal indicator concentrations (faecal coliform concentrations are reported herein) were measured at 41 riverine locations, the 15 largest wastewater treatment works (WwTWs) and 15 combined sewer overflows (CSOs) across the Ribble basin over a 44-day period during the 2002 bathing season. The sampling programme included targeting rainfall-induced high flow events and sample results were categorised as either base flow or high flow. At the riverine sites, geometric mean faecal coliform concentrations showed statistically significant elevation at high flow compared to base flow. The resultant faecal coliform flux estimates revealed that over 90% of the total organism load to the Ribble Estuary was discharged by sewage related sources during high flow events. These sewage sources were largely related to the urban areas to the south and east of the Ribble basin, with over half the

  5. Integrating dynamic ecohydrological relations with the catchment response: A multi-scale hydrological modeling effort in a monsoonal regime basin

    Science.gov (United States)

    Mendez-Barroso, L. A.; Vivoni, E.; Robles-Morua, A.; Yepez, E. A.; Rodriguez, J. C.; Watts, C.; Saiz-Hernandez, J.

    2013-05-01

    Seasonal vegetation changes highly affect the energy and hydrologic fluxes in semiarid regions around the world. Accounting for different water use strategies among drought-deciduous ecosystems is important for understanding how these exploit the temporally brief and localized rainfall pulses of the North American Monsoon (NAM). Furthermore, quantifying these plant-water relations can help elucidate the spatial patterns of ecohydrological processes at catchment scale in the NAM region. In this effort, we focus on the San Miguel river basin (~ 3500 km2) in Sonora, Mexico, which exhibits seasonal vegetation greening that varies across ecosystems organized along mountain fronts. To assess the spatial variability of ecohydrological conditions, we relied on diverse tools that included multi-temporal remote sensing observations, model-based meteorological forcing, ground-based water and energy flux measurements and hydrologic simulations carried out at multiple scales. We evaluated the impact of seasonal vegetation dynamics on evapotranspiration (ET), its partitioning into soil evaporation (E) and plant transpiration (T), as well as their spatiotemporal patterns over the course of the NAM season. We utilized ground observations of soil moisture and evapotranspiration estimated by the eddy covariance method at two sites, as well as inferences of ET partitioning from stable isotope measurements, to test the numerical simulations. We found that ecosystem phenological differences lead to variations in the time to peak in transpiration during a season and in the overall seasonal ratio of transpiration to evapotranspiration (T/ET). A sensitivity analysis of the numerical simulations revealed that vegetation cover and the soil moisure threshold at which stomata close exert strong controls on the seasonal dominance of transpiration or evaporation. The dynamics of ET and its partitioning are then mapped spatially revealing that mountain front ecosystems utilize water differently

  6. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Physiographic Provinces

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents the area of each physiographic province (Fenneman and Johnson, 1946) in square meters, compiled for every MRB_E2RF1 catchment of...

  7. Selected examples of needs for long term pilot areas in Mediterranean catchments: a mountain traditional agricultural system and a large and regulated hydrographic basin in Southern Spain

    Science.gov (United States)

    José Polo, María; Herrero, Javier; Millares, Agustín; José Pérez-Palazón, María; Pimentel, Rafael; Aguilar, Cristina; Jurado, Alicia; Contreras, Eva; Gómez-Beas, Raquel; Carpintero, Miriam; Gulliver, Zacarías

    2015-04-01

    Integrated River Basin Management (IRBM) aims at planning water, land and other natural resources for an equitable and sustainable management, also capable of preserving or restoring freshwater ecosystems. Long term series of significant variables at different scales and a sound knowledge of the river basin processes are needed to establish the current state and past&future evolution of the hydrological system, soil use and vegetation distribution, and their social impacts and feedbacks. This is particularly crucial if future scenario analyses are to be performed to assess decision-making processes and adaptive plans. This work highlights the need for an adequate design and development of process-oriented monitoring systems at the basin scale in a decision-making framework. First, the hydrologic monitoring network of the Guadalfeo River Basin, in the southern face of Sierra Nevada Range (Spain), is shown, in a pilot catchment of 1300 km2 in which snow processes in Mediterranean conditions have been studied over the last ten years with a holistic approach. The network development and the main features of the dataset are described together with their use for different scientific and environmental applications; their benefits for assessing social and economic impact in the rural environment are shown from a study case in which the sustainability of ancient channels fed by snowmelt, in use since the XIIIth century for traditional irrigated crops in the mountainous area, was assessed in a future scenarios analyses. Secondly, the standard flow and water quality monitoring networks in the Guadalquivir River Basin, a large (57400 km2) and highly regulated agricultural catchment in southern Spain, are shown, and their strengths and weaknessess for an IRBM framework are analysed. Sediments and selected pollutants are used to trace soil erosion and agricultural/urban exports throughout the catchment, and the final loads to the river estuary in the Atlantic Ocean are assessed

  8. Hydro-meteorological functioning of the Eastern Andean Tropical Montane Cloud Forests: Insight from a paired catchment study in the Orinoco river basin highlands

    Science.gov (United States)

    Ramirez, Beatriz; Teuling, Adriaan J.; Ganzeveld, Laurens; Leemans, Rik

    2016-04-01

    Tropical forests regulate large scale precipitation patterns and catchment-scale streamflow, while tropical mountains influence runoff by orographic effects and snowmelt. Along tropical elevation gradients, these climate/ecosystem/hydrological interactions are specific and heterogeneous. These interactions are poorly understood and represented in hydro-meteorological monitoring networks and regional or global earth system models. A typical case are the South American Tropical Montane Cloud Forests (TMCF), whose water balance is strongly driven by fog persistence. This also depends on local and up wind temperature and moisture, and changes in this balance alter the impacts of changes in land use and climate on hydrology. These TMCFs were until 2010 only investigated up to 350km from the coast. Continental TMCFs are largely ignored. This gap is covered by our study area, which is part of the Orinoco river basin highlands and located on the northern Eastern Andes at an altitudinal range of 1550 to 2300m a.s.l. The upwind part of our study area is dominated by lowland savannahs that are flooded seasonally. Because meteorological stations are absent in our study area, we first describe the spatial and seasonal meteorological variability and analyse the corresponding catchment hydrology. Our hydro-meteorological data set is collected at three gauged neighbouring catchments with contrasting TMCF/grassland cover from June 2013 to May 2014 and includes hourly solar radiation, temperature, relative humidity, wind speed, precipitation, soil moisture and runoff measurements. We compare our results with recent TCMF studies in the eastern Andean highlands in the Amazon basin. The studied elevational range always shows wetter conditions at higher elevations. This indicates a positive relation between elevation and fog or rainfall persistence. Lower elevations are more seasonally variable. Soil moisture data indicate that TMCFs do not use persistently more water than grasslands

  9. Calculation of Sediment yield at the S 7-4 catchment of the Shirindareh Watershed of Iran using the River Basins model

    Science.gov (United States)

    Spalevic, Velibor; Barovic, Goran; Vujacic, Dusko; Mijanovic, Dragica; Curovic, Milic; Tanaskovik, Vjekoslav; Behzadfar, Morteza

    2016-04-01

    Soil erosion is driven by complex processes involving detachment of material caused by raindrops and flow tractions, which is further transported by the wind or by the water flow. The region of Shirindareh Watershed of Iran is particularly prone to erosion because it is subject to long dry periods followed by heavy erosive rainfalls, falling on steep slopes with soils prone to erosion. The identification of areas that are vulnerable to those processes is needed for improving our knowledge about the extent of the areas affected and for developing measures to control the problem. In our opinion, models can be very supportive tools for understanding of the soil erosion and sediment transport at the watershed scale. This study aims to illustrate the possibility in computing the runoff and sediment yield at the catchment scale using the River Basins model of Spalevic, which is based on the Erosion Potential Method of Garilovic. We apply the mode in the S 7-4 catchment of the Shirindareh Watershed of Iran using the computer graphic model, which allowed the quantification of the environmental effects of erosion and the land use measures applied at the studied area. Model calculations showed that the calculated peak discharge from the river basin was 61 m3 s-1 for the incidence of 100 years and the net soil loss was 5806 m3 per year, specific 159 m3km-2 per year. According to Gavrilovic this amount of soil loss indicates very weak erosion category. The method we used in this study can also be of interest for soil erosion modelling in other basins. The proper implementation of best management practices and control measures are crucial for protecting land resources in the Shirindareh Watershed and the other river basins with similar physical - geographical conditions.

  10. Drainage architecture and sediment routing in erosive catchments within the Ebro Eiver sedimentary basin (NE Iberian Peninsula)

    Science.gov (United States)

    Castelltort, Xavier; Colombo, Ferran; Carles Balasch Solanes, Josep

    2016-04-01

    The Ebro Basin (EB) is the result of filling a foreland basin located between active mountain ranges during the Paleogene compressive phases, and later affected by phases of distension in the Neogene. The arrangement of filler material is monocline in the eastern margin and in the contact with the Catalan Coastal Range (CCR). This has repercussions on the model of emptying the erosive basins and in the drainage that took place in the margins of the original sedimentary basin. One can speak of a drainage architecture and sediment routing associated to a monocline erosive basin model. The monocline topography in the original margin of EB encouraged the formation of a string of erosive basins around the contact with CCR, which are the result of headward erosion towards the center of the EB of the rivers draining the CCR towards the Valencia Trough. At the time, the transition from the EB in its initial condition of endorheic to exorheic was through one of these monocline erosive basins. The erosive basins emptied by means of two vectors. On the one hand, growth in surface of the basin by deepening anaclinal streams through resistant beds of monocline stratigraphic succession that empty and link small depressions that increase laterally on the less resistant lithologic member. Moreover, the new drainage system entrenches as the exit point of the basin does, thanks to gradients created by distensional movements of the Neogene Valencia Trough. Growth and entrenchment model of river basins, as well as, sedimentary deposits and landforms generated by these processes are described and analyzed.

  11. The challenges of catchment hydrological modelling in the Himalayan region: a case study from the Dudh Kosi River basin of Eastern Nepal

    Science.gov (United States)

    Nepal, Santosh; Bajracharya, Sagar R.; Shea, Joseph; Wahid, Shahriar M.; Shrestha, Arun B.; Flügel, Wolfgang-Albert

    2014-05-01

    Catchment-scale hydrological modelling in the Himalayan region suffers from multiple issues that affect our ability to represent the hydrological dynamics of a river system. Due to a lack of monitoring infrastructure, especially in the high-altitude areas, the spatial distribution of precipitation is essentially unknown. Therefore, the regionalization of precipitation in river basins is a challenging task that has implications in the modelling approach at different levels. This paper explores the uncertainty in modelled discharge using different precipitation input datasets in the glaciated catchment of the Dudh Kosi River basin in Eastern Nepal (3712 km2). The basin hosts some of the world's highest mountain peaks, including Mt Everest. Six precipitation stations, which cover mostly the lowland area of the basin, give a station density of one station per 618 km2. First, we examine precipitation dynamics in the study area based on the observed data. Second, the process-oriented distributed J2000 hydrological model is applied in the Dudh Kosi River basin. Third, the model is run with APHRODITE-(V1003R1), CPC-RFE-(2.0) and TRMM-(V7) precipitation products to compare observed and modelled discharge. Nearly 82% of the precipitation occurs during the monsoon season (June - September), and the limited station observations suggest that there is non-uniform distribution of precipitation in which the underlying topography has a great influence. The maximum precipitation occurred at the station which is located on the middle hills region, followed by the station located at the foothills of the Higher Himalaya. Compared to the observed precipitation, the TRMM product is found to be 7% less than the observed data, whereas the other two products were up to 35% less. The model was applied with the six stations data and the regionalization was carried out using Inverse Distance Weighting (IDW) method to simulate the hydrograph. The model was first applied between 1985-1997 in

  12. SUGAR CANE GROWING AND CATTLE GRAZING AS DRIVERS TO WETLAND DEGRADATION IN UGANDA: A case of upper river Ruizi and Iguluibi catchments Lake Victoria basin

    Science.gov (United States)

    Nakiyemba Were, Alice; Isabirye, Moses; Mathijs, Erik; Deckers, Jozef; Poesen, Jean

    2010-05-01

    Introduction: This study was conducted with in the framework of the VLIR-OI project with the aim of making contributions to the Diagnosis and Remediation of Land Degradation Processes in the Riparian Zone of Lake Victoria Uganda in view of reducing sediment pollution of the Lake Waters with a special focus on the upper river Ruiz and Iguluibi catchments. The study seeks to investigate Sugarcane growing and cattle grazing as drivers to wetland degradation in light of the current farming systems and practices and their contributions to land degradation and pollution of the Lake Victoria waters. Vegetation especially wetlands improves the resistance to erosion. The removal of riparian vegetation tends to accelerate surface erosion as a result of human activities. Increased erosion with in the catchments due to clearing of wetlands for sugarcane growing and cattle grazing has caused adverse increased sedimentation, degraded the water quality, and reduced the water productivity of the Lake Victoria Basin. Methods: We conducted a qualitative and quantitative study to investigate Sugarcane growing and cattle grazing as drivers to wetland degradation in Uganda in light of the current farming systems and practices and their socio-economic contributions to wetland degradation and pollution of the Lake Victoria waters. Focus group discussions, key informant interviews, semi structured interviews and observations were undertaken with the relevant stakeholders in the community. Results: Findings reveal that in Iguluibi catchment, sugarcane growing is now a major activity indicating land use change since the 1990s. Community members said when planting sugarcane all vegetations including all trees are cut leaving the land bare to allow the tractor to clear the land for cultivation. This has left the land bare without any natural vegetation with increased erosion hence eventually loss of soil fertility and increased sediment pollution to the Lake Victoria waters. As a result of

  13. Challenges of regional hydrological modelling in the Elbe River basin : investigations about model fidelity on sub-catchment level

    OpenAIRE

    Conradt, Tobias

    2013-01-01

    Within a research project about future sustainable water management options in the Elbe River basin, quasi-natural discharge scenarios had to be provided. The semi-distributed eco-hydrological model SWIM was utilised for this task. According to scenario simulations driven by the stochastical climate model STAR, the region would get distinctly drier. However, this thesis focuses on the challenge of meeting the requirement of high model fidelity even for smaller sub-basins. Usually, the quality...

  14. The influence of the geomorphological factors on the relief modelling within Eselnita hydrographic basin (Danube catchment/Romania

    Directory of Open Access Journals (Sweden)

    DANIELA VLAD

    2012-08-01

    Full Text Available Developed on the south-eastern side of Almãjului Mountains, Eşelniţa drainage basin neighbours upon the following basins: upon S – SV with Mala, upon SV - V with Mraconia, upon V – NV with Berzasca, upon NV - NNE with Nera and on the NNE – SE direction with Cerna. The basin has a surface of 77 km2 and present a 5th degree hydrographic network according to Horton-Strahler ranking system, tributary to Danube by means of Eşelniţa main collector. Developed in a mountain landscape, the basin presents different levels held between minimum altitude of 64 m at the confluence with the Danube and maximum altitude of 1107 m, thus presenting a difference of 1043 m. Geological formations within the basin belong predominant to the Danubian Domain, so in central and upper courses, these are represented by a crystalline foundation and by magmatic rocks of intrusive nature covered by very small areas of sediment located in the northwest (belong to the Lower Jurassic and in the south-eastern (belongs to the Upper Cretaceous of the basin. But in the lower course, there are both crystalline and the sedimentary formations, last being integrated to Orşova depression and whose presence is related to the evolution of the Danube. Morphometric indices of Eşelniţa basin allows the distinction of a higher sector, mountainous terrain with high energy under a relatively increased fragmentation and depression sector with low relief energy and also with an intense fragmentation of the existing sedimentary rocks wich favors erosion manifestation in the context of deforestation action.

  15. Use of Isotopes in Assessing the Response of Groundwater to Cross-Catchments Water Diversion in the Tarim Basin

    International Nuclear Information System (INIS)

    Since 2000, more than 2 billion m3 of water has been diverted from the Peacock River to the neighbouring Lower Tarim River in NW China via a 900 km canal for ecosystem rescue by cross-catchment water diversion. Isotope techniques have been used in the riparian groundwater- river interactions along the 350 km long river channel through sampling of monitoring wells and river stream as well as soil profiles. Stable isotopes (δ2H, δ 18O) show that groundwater is enriched in heavy isotopes, attributed to evaporation during recharge. Tritium data show that the extent of modern recharge is limited to 600-1500 m from the riverbank in the middle reaches and 200-600 m in the lower reaches. The salinity of groundwater is affected by river recharge, residence time and evapotranspiration. The zone of appropriate water table for arid plants is confined to a narrow scope. The assessment calls for a more favourable water allocation and management scheme catchment wide. (author)

  16. Crop yield risk analysis and mitigation of smallholder farmers at quaternary catchment level: Case study of B72A in Olifants river basin, South Africa

    Science.gov (United States)

    Magombeyi, Manuel S.; Taigbenu, Akpofure E.

    Currently, Sub-Sahara is experiencing increased frequency of disasters either as floods or droughts which depletes the scarce resources available to sustain increasing populations. Success in preventing food shortages in the African continent can only be achieved by understanding the vulnerability and risk of the majority of smallholder farmers under rainfed and supplementary irrigation coupled with appropriate interventions. Increased frequency of floods, droughts and dry spells pose an increasing threat to the smallholder farmers’ food security and water resources availability in B72A quaternary catchment of the Olifants river basin in South Africa. This paper links maize crop yield risk and smallholder farmer vulnerability arising from droughts by applying a set of interdisciplinary indicators (physical and socio-economic) encompassing gender and institutional vulnerabilities. For the study area, the return period of droughts and dry spells was 2 years. The growing season for maize crop was 121 days on average. Soil water deficit during critical growth stages may reduce potential yields by up to 62%, depending on the length and severity of the moisture deficit. To minimize grain yield loss and avoid total crop failures from intra-seasonal dry spells, farmers applied supplementary irrigation either from river water or rainwater harvested into small reservoirs. Institutional vulnerability was evidenced by disjointed water management institutions with lack of comprehension of roles of higher level institutions by lower level ones. Women are most hit by droughts as they derived more than 90% of their family income from agriculture activities. An enhanced understanding of the vulnerability and risk exposure will assist in developing technologies and policies that conform to the current livelihood strategies of smallholder, resource-constrained farmers. Development of such knowledge base for a catchment opens avenues for computational modeling of the impacts of

  17. SPATIAL VARIABILITY OF DRY SPELLS A spatial and temporal rainfall analysis of the Pangani basin and Makanya catchment, Tanzania

    Science.gov (United States)

    Fischer, B. M. C.; Savenije, H. H. G. H. H. G.

    2009-04-01

    Rainfall and soil moisture are key parameters for food production and which are spatial and temporal variable. In a ever growing world the stress on water for food production increases. Farmers especially in semi arid regions with rain fed agriculture are more often forced to make away from "A" locations where water is available to water scares "B" or worse locations. Obliged by availability of arable land, tradition, customs, natural 6th sense or farmers cleverness. To improve agricultural yields a better water resource planning ,supported by system knowledge, is needed. This study describes a Markov bases dry spell tool which can fulfil in this need. By making use of Markov properties of rainfall, the temporal variability has been analysed. Plotting the derived seasonal transition probabilities vs. the rainfall amount a spatial variable power function could be derived. The spatial and temporal knowledge of rainfall was combined in the Markov based dry spell tool. For a given probability the tool provides a dry spell map. The dry spell tool is a powerful tool to assess vulnerability of dry spells based on meteorological data. The meteorological dry spell in combination with the agricultural dry spell length or critical dry spell length, which is determined by soil and vegetation characteristics, risk maps of an area to the vulnerability of dry spells could be made. The tool was applied in a case study in the Makanya catchment and showed: Compared to the lower middle part of the catchment, high altitude parts of the catchment receive higher amounts of rainfall, have shorter meteorological dry spells and are more resilient to dry spells due to their soil and vegetation characteristics. As a result one can state that farmers living in mountainous areas are blessed by their location. They receive more rain and have lower probability of long dry spells, higher probability of crop success and a higher probability of high yields, in contrast to the farmers in the valley

  18. Attributes for MRB_E2RF1 Catchments by Major Rivers Basins in the Conterminous United States: Total Precipitation, 2002

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents the catchment-average total precipitation in millimeters multiplied by 100 for 2002, compiled for every MRB_E2RF1 catchment of...

  19. Suspended sediment yield and metal contamination in a river catchment affected by El Niño events and gold mining activities: the Puyango river basin, southern Ecuador

    Science.gov (United States)

    Tarras-Wahlberg, N. H.; Lane, S. N.

    2003-10-01

    The suspended sediment yield and the transfer of polluted sediment are investigated for the Puyango river basin in southern Ecuador. This river system receives metal (Cd, Cu, Hg, Pb and Zn) and cyanide pollution generated by mining, and is associated with large-scale hydrological variability, which is partly governed by El Niño events. Field sampling and statistical modelling methods are used to quantify the amount of mine tailings that is discharged into the basin. Annual suspended sediment yields are estimated using a novel combination of the suspended sediment rating method and Monte Carlo simulations, which allow for propagation of the uncertainties of the calculations that lead to final load estimates. Geochemical analysis of suspended and river bed sediment is used to assess the dispersion and long-term fate of contaminated sediment within the river catchment. Knowledge of the inter- and intra-annual variation in suspended sediment yield is shown to be crucial for judging the importance of mining discharges, and the extent to which the resultant pollution is diluted by river flows. In wet years, polluted sediments represent only a very small proportion of the yield estimates, but in dry years the proportion can be significant. Evidence shows that metal contaminated sediments are stored in the Puyango river bed during low flows. Large flood events flush this sediment periodically, both on an annual cycle associated with the rainy season, and also related to El Niño events. Therefore, environmental impacts of mining-related discharges are more likely to be severe during dry years compared with wet years, and in the dry season rather than the wet season. The hydrological consequences of El Niño events are shown to depend upon the extent to which these events penetrate inland. It is, thus, shown that the general conclusion that El Niño events can significantly affect suspended sediment yields needs evaluation with respect to the particular way in which those

  20. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Nutrient Inputs from Fertilizer and Manure, Nitrogen and Phosphorus (N&P), 2002

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This tabular data set represents the total amount of nitrogen and phosphorus, in kilograms for the year 2002, compiled for every MRB_E2RF1 catchment of the Major River Basins (MRBs, Crawford and others, 2006). The source data set is County-Level Estimates of Nutrient Inputs to the Land Surface of the Conterminous United States, 1982-2001 (Ruddy and others, 2006). The MRB_E2RF1 catchments are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) ERF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002; Brakebill and others, 2011). Data were compiled for every MRB_E2RF1 catchment for the conterminous United States covering New England and Mid-Atlantic (MRB1), South Atlantic-Gulf and Tennessee (MRB2), the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy (MRB3), the Missouri (MRB4), the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf (MRB5), the Rio Grande, Colorado, and the Great basin (MRB6), the Pacific Northwest (MRB7) river basins, and California (MRB8).

  1. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Nutrient Application (Phosphorus and Nitrogen) for Fertilizer and Manure Applied to Crops (Cropsplit), 2002

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This tabular data set represents the estimated amount of phosphorus and nitrogen fertilizers applied to selected crops for the year 2002, compiled for every MRB_E2RF1 catchment of Major River Basins (MRBs, Crawford and others, 2006). The source data set is based on 2002 fertilizer data (Ruddy and others, 2006) and tabulated by crop type per county (Alexander and others, 2007). The MRB_E2RF1 catchments are based on a modified version of the U.S. Environmental Protection Agency's (USEPA) ERF1_2 and include enhancements to support national and regional-scale surface-water quality modeling (Nolan and others, 2002; Brakebill and others, 2011). Data were compiled for MRB_E2RF1 catchments for the conterminous United States covering New England and Mid-Atlantic (MRB1), South Atlantic-Gulf and Tennessee (MRB2), the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy (MRB3), the Missouri (MRB4), the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf (MRB5), the Rio Grande, Colorado, and the Great basin (MRB6), the Pacific Northwest (MRB7) river basins, and California (MRB8).

  2. Participatory watershed management to decrease land degradation and sediment transport in Kagera and Nyando catchments of Lake Victoria basin

    OpenAIRE

    Kenge, James Gunya

    2009-01-01

    Attention to participatory watershed management is increasing across the developing world as soil erosion continues to degrade agricultural land; reservoirs and irrigation infrastructure are clogged with sediment. The realization of the importance of watersheds is crucial for sustainable utilization especially in developing countries where rural livelihoods and economies are highly dependant on the exploitation of natural resources. The Lake Victoria basin is characterized by high population ...

  3. From the Highest to the Deepest: A River-Sea Dispersal System that Links A Mountainous Catchment to the Deep-Sea Basin (Invited)

    Science.gov (United States)

    Liu, J. T.; Hsu, R. T.

    2013-12-01

    Gaoping River (GPR) is a small mountainous river whose source area is located in the southern Central Range of Taiwan, about 3900 m above sea level. It has an average gradient of 1:150. Both the chemical and physical weathering rates for the GPR catchment are higher than the world average. Approximately 1 km seaward from the mouth of the GPR is the head of the Gaoping Submarine Canyon (GPSC). GPR annually discharges 35 Mt of sediment into the sea, most of which enters the GPSC. The GPSC owes its existence to tectonic processes related to the collision of the Philippine Plate and the Eurasia Plate. The canyon extents from the mouth of GPR, cutting through the Gaoping shelf and slope, and merges into the northeastern Manila Trench over a distance of about 260 km in water depth over 3000 m. It is a major conduit for the transport of terrestrial sediment to the South China Sea (SCS) and the landward transport of particles of marine origin in the SCS. The thickness of the tidally-dominated benthic nepheloid layer (BNL) in the GPSC can exceed 200 m, in which the temperature, flow, and suspended sediment concentration show distinctive tidal oscillations. Both semidiruanl barotropic and baroclinic tides are important in the canyon. In the GRSC the normal transport of suspended sediment associated with tidal propagation from offshore is up-canyon yet episodic sediment transports associated with episodic gravity-driven events are down-canyon. Typhoon-induced river floods often ignite turbidity currents (TCs) in the GPSC. Therefore, hperpycnal river plume and the ensuing TCs form an effective pathway to transport large amount of terrestrial sediment and carbon (fresh and aged) to the SCS basin. However, due to the extensive disturbance in the GPR catchment by typhoon-related deep erosion of hillslopes and incision of river channels, the ';fresh' flood sediment exported by GPR during and immediately after typhoons contains old sediment as defined by the absence of 7Be

  4. Quantifying uncertainty in the impacts of climate change on river discharge in sub-catchments of the Yangtze and Yellow River Basins, China

    Directory of Open Access Journals (Sweden)

    H. Xu

    2011-01-01

    Full Text Available Quantitative evaluations of the impacts of climate change on water resources are primarily constrained by uncertainty in climate projections from GCMs. In this study we assess uncertainty in the impacts of climate change on river discharge in two catchments of the Yangtze and Yellow River Basins that feature contrasting climate regimes (humid and semi-arid. Specifically we quantify uncertainty associated with GCM structure from a subset of CMIP3 AR4 GCMs (HadCM3, HadGEM1, CCSM3.0, IPSL, ECHAM5, CSIRO, CGCM3.1, SRES emissions scenarios (A1B, A2, B1, B2 and prescribed increases in global mean air temperature (1 °C to 6 °C. Climate projections, applied to semi-distributed hydrological models (SWAT 2005 in both catchments, indicate trends toward warmer and wetter conditions. For prescribed warming scenarios of 1 °C to 6 °C, linear increases in mean annual river discharge, relative to baseline (1961–1990, for the River Xiangxi and River Huangfuchuan are +9% and 11% per +1 °C respectively. Intra-annual changes include increases in flood (Q05 discharges for both rivers as well as a shift in the timing of flood discharges from summer to autumn and a rise (24 to 93% in dry season (Q95 discharge for the River Xiangxi. Differences in projections of mean annual river discharge between SRES emission scenarios using HadCM3 are comparatively minor for the River Xiangxi (13 to 17% rise from baseline but substantial (73 to 121% for the River Huangfuchuan. With one minor exception of a slight (−2% decrease in river discharge projected using HadGEM1 for the River Xiangxi, mean annual river discharge is projected to increase in both catchments under both the SRES A1B emission scenario and 2° rise in global mean air temperature using all AR4 GCMs on the CMIP3 subset. For the River Xiangxi, there is substantial uncertainty associated with GCM structure in the magnitude of the rise in flood (Q05 discharges (−1 to 41% under SRES A1B and −3 to 41% under 2

  5. Soil and plant composition in the Noun river catchment basin, Western Cameroon: a contribution to the development of a biogeochemical baseline

    Science.gov (United States)

    Njofang, Clémentine; Matschullat, Jörg; Amougou, Akoa; Tchouankoué, Jean Pierre; Heilmeier, Hermann

    2009-02-01

    Soils and selected edible plants of the Noun river catchment basin of western Cameroon were sampled to investigate the distribution of trace elements, based on the preliminary idea of unusual anomalies. Analytical techniques for trace elements included ICP-AES, GF-AAS, and ICP-MS. Further soil analyses comprised the mineralogy and contents of the biogenic elements carbon, nitrogen and sulphur (CNS). The trace element concentrations in the soils reflect those of the lithogeochemical background of the pluto-volcanic rocks of the region. This is consistent with the results from the mineralogical analyses and physicochemical parameters such as pH, taken in the field, which also do not suggest any geochemical anomaly. Most trace elements analyzed in the plants showed concentrations that reflect those of the soils (Al, Fe, Ti, and Rb). However, some trace elements were enriched in the plants as compared to the soils, such as Zn, Cu, Cd, Mo (excluding yam), Ni (peanut), Ba (peanut), Sr (peanut, bean), and B. Trace elements such as As, Cr, V, and Se were not bioavailable for all the analyzed plants. Besides, trace elements such as Cu, Zn, Mo, Fe, Al, Ni, B, Ti, Rb, Cs, and Ba were in the range of phytotoxicity and reached or exceeded human food tolerance level (Cu). The plants with seeds showed a higher absorption of trace elements compared to plants with tubercles.

  6. REACH-ER: a tool to evaluate river basin remediation measures for contaminants at the catchment scale

    Science.gov (United States)

    van Griensven, Ann; Haest, Pieter Jan; Broekx, Steven; Seuntjens, Piet; Campling, Paul; Ducos, Geraldine; Blaha, Ludek; Slobodnik, Jaroslav

    2010-05-01

    The European Union (EU) adopted the Water Framework Directive (WFD) in 2000 ensuring that all aquatic ecosystems meet ‘good status' by 2015. However, it is a major challenge for river basin managers to meet this requirement in river basins with a high population density as well as intensive agricultural and industrial activities. The EU financed AQUAREHAB project (FP7) specifically examines the ecological and economic impact of innovative rehabilitation technologies for multi-pressured degraded water bodies. For this purpose, a generic collaborative management tool ‘REACH-ER' is being developed that can be used by stakeholders, citizens and water managers to evaluate the ecological and economical effects of different remedial actions on waterbodies. The tool is built using databases from large scale models simulating the hydrological dynamics of the river basing and sub-basins, the costs of the measures and the effectiveness of the measures in terms of ecological impact. Knowledge rules are used to describe the relationships between these data in order to compute the flux concentrations or to compute the effectiveness of measures. The management tool specifically addresses nitrate pollution and pollution by organic micropollutants. Detailed models are also used to predict the effectiveness of site remedial technologies using readily available global data. Rules describing ecological impacts are derived from ecotoxicological data for (mixtures of) specific contaminants (msPAF) and ecological indices relating effects to the presence of certain contaminants. Rules describing the cost-effectiveness of measures are derived from linear programming models identifying the least-cost combination of abatement measures to satisfy multi-pollutant reduction targets and from multi-criteria analysis.

  7. Long-term integrated river basin planning and management of water quantity and water quality in mining impacted catchments

    Science.gov (United States)

    Pohle, Ina; Zimmermann, Kai; Claus, Thomas; Koch, Hagen; Gädeke, Anne; Uhlmann, Wilfried; Kaltofen, Michael; Müller, Fabian; Redetzky, Michael; Schramm, Martina; Schoenheinz, Dagmar; Grünewald, Uwe

    2015-04-01

    During the last decades, socioeconomic change in the catchment of the Spree River, a tributary of the Elbe, has been to a large extent associated with lignite mining activities and the rapid decrease of these activities in the 1990s. There are multiple interconnections between lignite mining and water management both in terms of water quantity and quality. During the active mining period a large-scale groundwater depression cone has been formed while river discharges have been artificially increased. Now, the decommissioned opencast mines are being transformed into Europe's largest man-made lake district. However, acid mine drainage causes low pH in post mining lakes and high concentrations of iron and sulphate in post mining lakes and the river system. Next to potential changes in mining activities, also the potential impacts of climate change (increasing temperature and decreasing precipitation) on water resources of the region are of major interest. The fundamental question is to what extent problems in terms of water quantity and water quality are exacerbated and whether they can be mitigated by adaptation measures. In consequence, long term water resource planning in the region has to formulate adaptation measures to climate change and socioeconomic change in terms of mining activities which consider both, water quantity and water quality aspects. To assess potential impacts of climate and socioeconomic change on water quantity and water quality of the Spree River catchment up to the Spremberg reservoir in the scenario period up to 2052, we used a model chain which consists of (i) the regional climate model STAR (scenarios with a further increase in temperature of 0 and 2 K), (ii) mining scenarios (mining discharges, cooling water consumption of thermal power plants), (iii) the ecohydrological model SWIM (natural water balance), (iv) the long term water management model WBalMo (managed discharges, withdrawal of water users, reservoir operation) and (v) the

  8. The Kara Bogaz Gol Bay, Lake Issyk Kul and Aral Sea sediments as archives of climate change in the Aral-Caspian catchment basin

    International Nuclear Information System (INIS)

    A 5-m long core of bottom sediments from the Kara Bogaz Gol Bay of the Caspian Sea, 4- m and 2-m cores from the Issyk Kul Lake of the Thian Shan Mountains, and a 4-m core from the Aral Sea were examined for evidence of climatic and environmental changes in the catchment basin of the Central Asia Region. The distribution of 18O and 13C in the bulk carbonates, 2H in the pore water, radiocarbon age, oxygen and hydrogen isotopes in the lake water, abundance of CaCO3, MgCO3, and the basic salt ions of Na+, K+, Cl-, SO42- in the cores were measured. The isotope and hydrogeochemical data of the Kara Bogaz Gol Bay sediments prove a historical scenario for the basin which suggests that fresh water has been discharged to the Caspian Sea during the Bay's humid episode across the Central Asia Region (∼ 9 Ka BP). Isotope and geochemical evidence indicate that the sedimentation of the upper core segment has taken place during the last ∼2.2 Ka BP in the environment of sea water recharged from the Central Caspian Basin. The period of between 4.3 and 6 Ka BP, which relates to the core depth interval of between 170 cm and 260 cm, demonstrates the most dramatic change in the sedimentation rate in the Issyk Kul Lake. It means that active melting of the mountain glaciers and warming of climate has happened just in this period. The swamp plant peat layers at depths of 230 cm and 130 cm indicate that during 3.5-3.7 Ka BP and 1.6-1.8 Ka BP the Aral Sea dried and broke up into a number of lakes and swamps. Sediment cores taken from the bottom of the Kara Bogaz Gol Bay, Lake Issyk Kul and Aral Sea show periodic rise and fall in water levels during the last ∼10 000 years. Two peat layers within the sediment core of the Aral Sea and dated at 1.6-1.8 Ka BP and 3.5-3.7 Ka BP demonstrate that this reservoir also periodically dried. (author)

  9. Quantification of water and sediment yield from small catchment in open mining areas: experience and results from Poro nickel mining basin in New Caledonia

    Science.gov (United States)

    Mathys, Nicolle; Allenbach, Michel; Wottling, Geoffroy; Carpentier, Laureen; Freydier, Perrine; Navarrot, Lucie

    2014-05-01

    Water management in mining environments is a major challenge of the mining projects. In New Caledonia large areas have been excavated for Nickel mining since the end of the 19th century. In the past, the bad management of the water and coarse sediments left scars in the landscape and management problems in the channel reaches downstream. Nowadays, open mining techniques no longer yield coarse material out of the mining areas but the management of water and fine sediment remains a difficult question as the suspended sediments reach the very fragile environment of the lagoon. In addition, in many areas, it threatens human activities in the downstream rivers. In order to quantify and understand the formation of runoff, erosion and sediment transport in small mining watersheds the "Hydromine" project was initiated in 2008 by the New Caledonia government (DAVAR) with the collaboration of the University of New Caledonia (UNC) and later with the scientific support of Irstea Grenoble. The questions addressed by this project are: - What is the response (water and sediments) of a mining watershed to a rainfall input? - What factors control this response? - What are the processes involved? And which are dominant in the various hydrometeorological situations? - What are the characteristics of the transported materials? - What is the efficiency of mitigation works in the mining area? Two small embedded catchments (0.09 and 0.30 km²) are monitored for measuring rainfall, runoff and fine sediment transport in the mining area of Poro, East cost of New Caledonia. Elevation ranges from 197 to 366 m.a.s.l. The slope are steep (36 % in average but locally up to 130%) and the vegetation cover is very low (20% for the larger basin, 0% for the headwater basin). Rainfall-runoff and discharge-sediment concentration (SSC) relationship were analysed at the event and annual time scale. As a result, we pointed out the main factors that influence the response of the basins to a rainfall event

  10. Flood-initiating catchment conditions: a spatio-temporal analysis of large-scale soil moisture patterns in the Elbe River basin

    OpenAIRE

    Nied, M.; Hundecha, Y.; Merz, B.

    2013-01-01

    Floods are the result of a complex interaction between meteorological event characteristics and pre-event catchment conditions. While the large-scale meteorological conditions have been classified and successfully linked to floods, this is lacking for the large-scale pre-event catchment conditions. Therefore, we propose classifying soil moisture as a key variable of pre-event catchment conditions and investigating the link between soil moisture patterns and flood occurrence ...

  11. Flood-initiating catchment conditions: a spatio-temporal analysis of large-scale soil moisture patterns in the Elbe river basin

    OpenAIRE

    Nied, M.; Hundecha, Y.; Merz, B.

    2012-01-01

    Floods are the result of a complex interaction between meteorological event characteristics and pre-event catchment conditions. While the large-scale meteorological conditions have been classified and successfully linked to floods, this is lacking for the large-scale pre-event catchment conditions. Therefore, we propose to classify soil moisture as a key variable of pre-event catchment conditions and to investigate the link between soil moisture patterns and flood occurrence in the Elbe ...

  12. Numerical groundwater flow modeling of the northern river catchment of the Lake Tana, Upper Blue Basin, Ethiopia

    Directory of Open Access Journals (Sweden)

    Nigussie Ayehu Asrie

    2016-06-01

    decreased by 32% and the simulation results showed on average head decrease of 8.06m over the whole area; with the highest fall 32m in wells to north and a minimum of about 1m in wells to the south of the catchment. In addition, the stream leakage, compared to the simulated steady state value and it was decreased by 75.36%. The simulated value showed an average 2.74m increased head over the whole area. High difference values were observed at Tseda (7.83m and Koladiba (7.3m. The minimum difference 1.08m was recorded at Angereb well field (observation 94. In addition, the stream leakage compared with the steady state value the change was about 87.43%. Keywords: MODFLOW 2000, Groundwater, Modelling, Sensitivity analysis, Simulation, Recharge

  13. Rainfall and runoff regime trends in mountain catchments (Case study area: the upper Hron River basin, Slovakia

    Directory of Open Access Journals (Sweden)

    Blahušiaková Andrea

    2015-09-01

    Full Text Available This paper presents an analysis of trends and causes of changes of selected hydroclimatic variables influencing the runoff regime in the upper Hron River basin (Slovakia. Different methods for identifying trends in data series are evaluated and include: simple mass curve analysis, linear regression, frequency analysis of flood events, use of the Indicators of Hydrological Alteration software, and the Mann-Kendall test. Analyses are performed for data from two periods (1931-2010 and 1961-2010. The changes in runoff are significant, especially in terms of lower QMax and 75 percentile values. This fact is also confirmed by the lower frequency and extremity of flood events. The 1980s are considered a turning point in the development of all hydroclimatic variables. The Mann-Kendall test shows a significant decrease in runoff in the winter period. The main causes of runoff decline are: the considerable increase in air temperature, the decrease in snow cover depth and changes in seasonal distribution of precipitation amounts.

  14. Statistical downscaling and projection of future temperature and precipitation change in middle catchment of Sutlej River Basin, India

    Indian Academy of Sciences (India)

    Dharmaveer Singh; Sanjay K Jain; R D Gupta

    2015-06-01

    Ensembles of two Global Climate Models (GCMs), CGCM3 and HadCM3, are used to project future maximum temperature (Max), minimum temperature (Min) and precipitation in a part of Sutlej River Basin, northwestern Himalayan region, India. Large scale atmospheric variables of CGCM3 and HadCM3 under different emission scenarios and the National Centre for Environmental Prediction/National Centre for Atmospheric Research reanalysis datasets are downscaled using Statistical Downscaling Model (SDSM). Variability and changes in Max, Min and precipitation under scenarios A1B and A2 of CGCM3 model and A2 and B2 of HadCM3 model are presented for future periods: 2020s, 2050s and 2080s. The study reveals rise in annual average Max, Min and precipitation under scenarios A1B and A2 for CGCM3 model as well as under A2 and B2 scenarios for HadCM3 model in 2020s, 2050s and 2080s. Increase in mean monthly Min is also observed for all months of the year under all scenarios of both the models. This is followed by decrease in Max during June, July August and September. However, the model projects rise in precipitation in months of July, August and September under A1B and A2 scenarios of CGCM3 model and A2 and B2 of HadCM3 model for future periods.

  15. Restoring the Mississippi River Basin from the Catchment to the Coast Defines Science and Policy Issues of Ecosystem Services Associated with Alluvial and Coastal Deltaic Floodplains: Soil Conservation, Nutrient Reduction, Carbon Sequestration, and Flood Control

    Science.gov (United States)

    Twilley, R.

    2014-12-01

    Large river systems are major economic engines that provide national economic wealth in transporting commerce and providing extensive agriculture production, and their coastal deltas are sites of significant ports, energy resources and fisheries. These coupled natural and social systems from the catchment to the coast depend on how national policies manage the river basins that they depend. The fundamental principle of the Mississippi River Basin, as in all basins, is to capitalize on the ability of fertile soil that moves from erosional regions of a large watershed, through downstream regions of the catchment where sediment transport and storage builds extensive floodplains, to the coastal region of deposition where deltas capture sediment and nutrients before exported to the oceans. The fate of soil, and the ability of that soil to do work, supports the goods and services along its path from the catchment to the coast in all large river basin and delta systems. Sediment is the commodity of all large river basin systems that together with the seasonal pulse of floods across the interior of continents provide access to the sea forming the assets that civilization and economic engines have tapped to build national and global wealth. Coastal landscapes represent some of the most altered ecosystems worldwide and often integrate the effects of processes over their entire catchment, requiring systemic solutions to achieve restoration goals from alluvial floodplains upstream to coastal deltaic floodplains downstream. The urgent need for wetland rehabilitation at landscape scales has been initiated through major floodplain reclamation and hydrologic diversions to reconnect the river with wetland processes. But the constraints of sediment delivery and nutrient enrichment represent some critical conflicts in earth surface processes that limit the ability to design 'self sustaining' public work projects; particularly with the challenges of accelerated sea level rise. Only

  16. The Immatsiak network of groundwater wells in a small catchment basin in the discontinuous permafrost zone of Northern Quebec, Canada: A unique opportunity for monitoring the impacts of climate change on groundwater (Invited)

    Science.gov (United States)

    Fortier, R.; Lemieux, J.; Molson, J. W.; Therrien, R.; Ouellet, M.; Bart, J.

    2013-12-01

    During a summer drilling campaign in 2012, a network of nine groundwater monitoring wells was installed in a small catchment basin in a zone of discontinuous permafrost near the Inuit community of Umiujaq in Northern Quebec, Canada. This network, named Immatsiak, is part of a provincial network of groundwater monitoring wells to monitor the impacts of climate change on groundwater resources. It provides a unique opportunity to study cold region groundwater dynamics in permafrost environments and to assess the impacts of permafrost degradation on groundwater quality and availability as a potential source of drinking water. Using the borehole logs from the drilling campaign and other information from previous investigations, an interpretative cryo-hydrogeological cross-section of the catchment basin was produced which identified the Quaternary deposit thickness and extent, the depth to bedrock, the location of permafrost, one superficial aquifer located in a sand deposit, and another deep aquifer in fluvio-glacial sediments and till. In the summer of 2013, data were recovered from water level and barometric loggers which were installed in the wells in August 2012. Although the wells were drilled in unfrozen zones, the groundwater temperature is very low, near 0.4 °C, with an annual variability of a few tenths of a degree Celsius at a depth of 35 m. The hydraulic head in the wells varied as much as 6 m over the last year. Pumping tests performed in the wells showed a very high hydraulic conductivity of the deep aquifer. Groundwater in the wells and surface water in small thermokarst lakes and at the catchment outlet were sampled for geochemical analysis (inorganic parameters, stable isotopes of oxygen (δ18O) and hydrogen (δ2H), and radioactive isotopes of carbon (δ14C), hydrogen (tritium δ3H) and helium (δ3He)) to assess groundwater quality and origin. Preliminary results show that the signature of melt water from permafrost thawing is observed in the

  17. The role of catchment classification in rainfall-runoff modeling

    OpenAIRE

    He, Y.; A. Bárdossy; E. Zehe

    2011-01-01

    A sound catchment classification scheme is a fundamental step towards improved catchment hydrology science and prediction in ungauged basins. Two categories of catchment classification methods are presented in the paper. The first one is based directly on physiographic properties and climatic conditions over a catchment and regarded as a Linnaean type or natural classification scheme. The second one is based on numerical clustering and regionalization methods and considered as a statistical o...

  18. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Average Saturation Excess-Overland Flow, 2002

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents the average value of saturation overland flow, in percent of total streamflow, compiled for every MRB_E2RF1 catchment of selected...

  19. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Mean Annual R-factor, 1971-2000

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents the average annual R-factor, rainfall-runoff erosivity measure, compiled for every MRB_E2RF1 catchment of selected Major River...

  20. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Average Daily Maximum Temperature, 2002

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents the average daily maximum temperature in Celsius multiplied by 100 for 2002, , compiled for every MRB_E2RF1 catchment of selected...

  1. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: 30-Year Average Annual Precipitation, 1971-2000

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents the 30-year (1971-2000) average annual precipitation in millimeters multiplied by 100 compiled for every MRB_E2RF1 catchment of...

  2. Multi-basin Hydrological Modeling at a Pan-European Scale Using a Combination of Catchment Classification and Regional Parameter Estimation

    Science.gov (United States)

    Hirpa, Y. H.; Kuentz, A.; Pechlivanidis, I.; Andersson, J.; Arheimer, B.

    2014-12-01

    Numerical hydrological models are essential tools for the retrieval of water information in many societal sectors. Although such models are usually applied at a catchment scale, there is an increasing need to model large spatial domains to be able to manage resources in a coordinated manner. However, modeling a large spatial domain brings with it a number of challenges. One of the issues that needs to be addressed is estimation of the model parameters under a situation where the physical and climate characteristics of the catchments making up the model domain are highly variable. A semi-distributed continuous hydrological model HYPE is applied to model daily stream flows over the entire pan-European region. The model includes simplified components to simulate human impacts, such as irrigation, reservoir regulation, and water abstraction. The entire region was subdivided into more than 35,000 subcatchments and a catchment classification scheme was implemented to group catchments based on similarity of their physiographic and climate characteristics. A range of catchment physiographic and climate attributes were used and principal component analysis was employed to reduce the dimensionality. These attributes were iteratively selected so that catchments of the same group have one or more of their hydrological signatures similar. The model parameters were estimated using a regionalization approach. Soil and landuse parameters were fixed based on soil and landuse classes respectively. Lake and irrigation parameters were estimated separately. Model parameters that are defined at a catchment scale were estimated for each group as functions of the catchment physical and climate characteristics. Simultaneous calibration was performed on a number of catchments to optimize the overall model performance and the functional relationships between the parameters and the catchment properties. ERA-interim reanalysis forcings were used as climate drivers and MODIS products were used

  3. Variations of temperature and hydrologic regimes of the region of Ladoga Lake catchment basin in the 20th and 21st centuries according to data of modern climate models

    Science.gov (United States)

    Rumyantsev, V. A.; Efimova, L. K.; Golitsyn, G. S.; Khon, V. Ch.

    2010-02-01

    In the region of the Ladoga Lake catchment basin, we perform data analysis on a set of different modern climate models with different Intergovernmental Panel on Climate Change (IPCC) scenarios in the 20th and 21st centuries; this set includes global models such as ECHAM4/OPYC3 (Max Planck Institute for Meteorology, Germany), HadCM3 (Hadley Centre Coupled Model, England), and RCAO (Rossby Centre Regional Atmosphere-Ocean) models. Two variants of the boundary conditions for these climate models (Rossby Center of Swedish Meteorological and Hydrological Institute, SMHI) are used. We present the results of a diagnosis of the model-predicted near-surface temperature (T), precipitation (P), evaporation (E), and water budget (P-E) in the Ladoga Lake catchment based on their comparison with empirical data in twentieth century. We obtain scenario estimates of the variations of temperature and hydrologic regimes of Ladoga Lake catchment when IPCC IS92a, A2, and B2 scenarios are fulfilled, describing the prognostic growth of anthropogenic emissions of greenhouse gases and aerosol to the atmosphere, and discuss the recommendations for their use.

  4. Impacts of climate change on the seasonality of low flows in 134 catchments in the River Rhine basin using an ensemble of bias-corrected regional climate simulations

    Directory of Open Access Journals (Sweden)

    M. C. Demirel

    2013-05-01

    Full Text Available The impacts of climate change on the seasonality of low flows are analysed for 134 sub-catchments covering the River Rhine basin upstream of the Dutch–German border. Three seasonality indices for low flows are estimated, namely seasonality ratio (SR, weighted mean occurrence day (WMOD and weighted persistence (WP. These indices are related to the discharge regime, timing and variability in timing of low flow events respectively. The three indices are estimated from: (1 observed low flows; (2 simulated low flows by the semi distributed HBV model using observed climate; (3 simulated low flows using simulated inputs from seven climate scenarios for the current climate (1964–2007; (4 simulated low flows using simulated inputs from seven climate scenarios for the future climate (2063–2098 including different emission scenarios. These four cases are compared to assess the effects of the hydrological model, forcing by different climate models and different emission scenarios on the three indices. The seven climate scenarios are based on different combinations of four General Circulation Models (GCMs, four Regional Climate Models (RCMs and three greenhouse gas emission scenarios. Significant differences are found between cases 1 and 2. For instance, the HBV model is prone to overestimate SR and to underestimate WP and simulates very late WMODs compared to the estimated WMODs using observed discharges. Comparing the results of cases 2 and 3, the smallest difference is found in the SR index, whereas large differences are found in the WMOD and WP indices for the current climate. Finally, comparing the results of cases 3 and 4, we found that SR has decreased substantially by 2063–2098 in all seven subbasins of the River Rhine. The lower values of SR for the future climate indicate a shift from winter low flows (SR > 1 to summer low flows (SR < 1 in the two Alpine subbasins. The WMODs of low flows tend to be earlier than for the current climate in

  5. Coevolution of volcanic catchments in Japan

    Science.gov (United States)

    Yoshida, Takeo; Troch, Peter A.

    2016-03-01

    Present-day landscapes have evolved over time through interactions between the prevailing climates and geological settings. Understanding the linkage between spatial patterns of landforms, soils, and vegetation in landscapes and their hydrological response is critical to make quantitative predictions in ungaged basins. Catchment coevolution is a theoretical framework that seeks to formulate hypotheses about the mechanisms and conditions that determine the historical development of catchments and how such evolution affects their hydrological response. In this study, we selected 14 volcanic catchments of different ages (from 0.225 to 82.2 Ma) in Japan. We derived indices of landscape properties (drainage density and slope-area relationship) as well as hydrological response (annual water balance, baseflow index, and flow-duration curves) and examined their relation with catchment age and climate (through the aridity index). We found a significant correlation between drainage density and baseflow index with age, but not with climate. The intra-annual flow variability was also significantly related to catchments age. Younger catchments tended to have lower peak flows and higher low flows, while older catchments exhibited more flashy runoff. The decrease in baseflow with catchment age is consistent with the existing hypothesis that in volcanic landscapes the major flow pathways change over time from deep groundwater flow to shallow subsurface flow. The drainage density of our catchments decreased with age, contrary to previous findings in a set of similar, but younger volcanic catchments in the Oregon Cascades, in which drainage density increased with age. In that case, older catchments were thought to show more landscape incision due to increasing near-surface lateral flow paths. Our results suggests two competing hypotheses on the evolution of drainage density in mature catchments. One is that as catchments continue to age, the hydrologically active channels retreat

  6. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: 30-Year Average Annual Precipitation, 1971-2000

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents the 30-year (1971-2000) catchment-average total annual precipitation in millimeters multiplied by 100 compiled for every MRB_E2RF1...

  7. Human impact variability on soil erosion during the Holocene based on valley floor sediments study in a Parisian basin fluvial catchment (France): crossing sedimentological, archaeological and palynological proxies

    Science.gov (United States)

    Morin, E.; Cyprien, A. L.; Gay-Ovejero, I.; Hinschberger, F.; Joly, C.; Macaire, J. J.; Poirier, N.; Visset, L.; Zadora-Rio, E.

    2009-04-01

    This work is part of the French CNRS ECLIPSE program « Impact anthropique sur l'érosion des sols et la sédimentation dans les zones humides associées durant l'Holocène ». It aims to reconstitute the evolution of human impact on soil erosion at various periods via the study of Holocene sedimentary archives. In this framework the Choisille catchment (288 km²; elevation: 50 - 200 m), tributary of the River Loire near Tours (France), has been the subject of an interdisciplinary study (sedimentology, geophysics, archaeology, palynology). 3 areas are investigated: a downstream stretch, a silicated sub-catchment area and a carbonated sub-catchment area. In the downstream stretch, located near ancient populated areas, drillings were performed along cross sections through valley floor alluviums. They show that a more or less organic clayey silty sedimentation started at the beginning of the Holocene. The sedimentation rates strongly increased at the beginning of the Subbatlantic (Bronze Age), simultaneously with the anthropogenic pressure advent (on set of agriculture), as shown by archaeological and palynological evidences (agricultural settlements, massive loggings on slopes, stockbreeding on valley-floor grasslands). In the silicated sub-catchment area, located upstream, drillings have shown that clayey silty sedimentation began at the end of the Roman Period, continued during the Early Middle Ages and increased during the High Middle Ages. Spatial archaeological prospecting has revealed a faint anthropogenic presence at the Roman Period, then a decline of population until the High Middle Ages, characterised by an agricultural revival. Palynological analyses have shown that, in this area, grasslands were dominant since the Early Middle Ages, with an increase in cereal cultures at the beginning of the High Middle Ages. In the carbonated sub-catchment area, drillings have shown that the more or less organic clayey silty sedimentation has begun during the Bronze Age

  8. Catchment scale human interventions in the Pamba Basin (Kerala, India) and their impact on estuarine ecosystem in the southern Vembanad Estuary

    OpenAIRE

    Elizabeth David, Shilly

    2013-01-01

    Anthropogenic inputs nowadays are the major source of nutrients leading to cultural eutrophication in the coastal aquatic systems. While river inputs of anthropogenic nutrients into coastal seas is considered a global problem, the database is biased towards temperate regions, developed countries and major river systems. Little is known on the amount and composition of nutrient fluxes from densely populated catchments in tropical regions and, in particular from small- and medium-sized rivers. ...

  9. Cesium-137 global fallout into the Ob river basin and its influence on the Kara sea contamination - Weapons fallout cesium-137 in the Ob' catchment landscapes and its influence on radioactive contamination of the Kara sea: Western Siberia, Russia

    Energy Technology Data Exchange (ETDEWEB)

    Semenkov, Ivan N.; Miroshnikov, Alexey Yu. [The Organization of Russian Academy of Sciences Institute of geology of ore deposits, petrography, mineralogy and geochemistry Russian Academy of Sciences (Russian Federation)

    2014-07-01

    There are several high level {sup 137}Cs anomaly zones detected in the deposits of the SW part of the Kara Sea. These anomaly zones were formed in the Ob' and the Enisey river estuaries due to the geochemical 'river-sea' boarder barrier. Level of radiocaesium specific activity reaches 120 Bq*kg{sup -1} in the deposits from these zones. Radiochemical enterprises occur in the both river basins. Their activity results in caesium-137 transfer into the river net. Vast area is contaminated by {sup 137}Cs after nuclear weapons in Semipalatinsk test-site and Kyshtym disaster in the Ob' river basin. Moreover, caesium comes to the Ob' and the Enisey river basins with global atmospheric fallout. The inflow of global fallout caesium-137 to the catchments is 660 kCi (320 kCi including radioactive decay) that is 4 times higher than {sup 137}Cs emission due to Fukushima disaster. Therefore, these river basins as any other huge catchment are an important sources of radioactive contamination of the Arctic Ocean. The aim of our research is to study behavior of global fallout caesium-137 in the landscapes of the Ob and the Enisey river basins. We studied caesium-137 behavior on the example of first order catchments in taiga, wetland, forest-steppe, steppe, and semi-arid landscapes. Geographic information system (GIS) was made. The tenth-order catchments (n=154, Horton coding system) shape 20-groups due to topsoil properties controlling cesium mobility. Eleven first-order basins, characterized 7 groups of tenth order catchments, were studied. And 700 bulk-core soil samples were collected in 2011-2013. Cesium runoff is calculated for 3 first-order river basins in taiga and forest-steppe landscapes. Storage of global fallout caesium-137 declines from undisturbing taiga first-order river basin (90% of cumulative fallout including radioactive decay)> arable steppe and fores-steppe (70 - 75%)> undisturbing wetland (60%). Caesium-137 transfer is high in arable lands

  10. Modeling the impact of development and management options on future water resource use in the Nyangores sub-catchment of the Mara Basin in Kenya

    Science.gov (United States)

    Omonge, Paul; Herrnegger, Mathew; Fürst, Josef; Olang, Luke

    2016-04-01

    Despite the increasing water insecurity consequent of competing uses, the Nyangores sub-catchment of Kenya is yet to develop an inclusive water use and allocation plan for its water resource systems. As a step towards achieving this, this contribution employed the Water Evaluation and Planning (WEAP) system to evaluate selected policy based water development and management options for future planning purposes. Major water resources of the region were mapped and quantified to establish the current demand versus supply status. To define a reference scenario for subsequent model projections, additional data on urban and rural water consumption, water demand for crop types, daily water use for existing factories and industries were also collated through a rigorous fieldwork procedure. The model was calibrated using the parameter estimation tool (PEST) and validated against observed streamflow data, and subsequently used to simulate feasible management options. Due to lack of up-to-date data for the current year, the year 2000 was selected as the base year for the scenario simulations up to the year 2030, which has been set by the country for realizing most flagship development projects. From the results obtained, the current annual water demand within the sub-catchment is estimated to be around 27.2 million m3 of which 24% is being met through improved and protected water sources including springs, wells and boreholes, while 76% is met through informal and unprotected sources which are insufficient to cater for future increases in demand. Under the reference scenario, the WEAP model predicted an annual total inadequate supply of 8.1 million m3 mostly in the dry season by the year 2030. The current annual unmet water demand is 1.3 million m3 and is noteworthy in the dry seasons of December through February at the irrigation demand site. The monthly unmet domestic demand under High Population Growth (HPG) was projected to be 1.06 million m3 by the year 2030. However

  11. Co-evolution of volcanic catchments in Japan

    Science.gov (United States)

    Yoshida, T.; Troch, P. A.

    2015-09-01

    Present day landscapes have evolved over time through interactions between the prevailing climates and geological settings. Understanding the linkage between spatial patterns of landforms, soils, and vegetation in landscapes and their hydrological response is critical to make quantitative predictions in ungaged basins. Catchment co-evolution is a theoretical framework that seeks to formulate hypotheses about the mechanisms and conditions that determine the historical development of catchments and how such evolution affects their hydrological response. In this study, we selected 14 volcanic catchments of different ages (from 0.225 to 82.2 Ma) in Japan. We derived indices of landscape properties (drainage density) as well as hydrological response (annual water balance, baseflow index, and flow duration curves) and examined their relation with catchment age and climate (through the aridity index). We found significant correlation between drainage density and baseflow index with age, but not with climate. The age of the catchments was also significantly related to intra-annual flow variability. Younger catchments tend to have lower peak flows and higher low flows, while older catchments exhibit more flashy runoff. The decrease of baseflow with catchment age confirms previous studies that hypothesized that in volcanic landscapes the major flow pathways have changed over time, from deep groundwater flow to shallow subsurface flow. The drainage density of our catchments decreased with age, contrary to previous findings in similar volcanic catchments but of significant younger age than the ones explored here. In these younger catchments, an increase in drainage density with age was observed, and it was hypothesized that this was because of more landscape incision due to increasing near-surface lateral flow paths in more mature catchments. Our results suggests two hypotheses on the evolution of drainage density in matured catchments. One is that as catchments further evolve

  12. Total mercury concentrations in an industrialized catchment, the Thur River basin (north-eastern France): geochemical background level and contamination factors

    OpenAIRE

    Rémy, Sandrine; Prudent, Pascale; Hissler, Christophe; Probst, Jean-Luc; Krempp, Gérard

    2003-01-01

    River bottom sediments and soils were collected from the industrialized Thur River basin (north-eastern France) to assess mercury contamination. The regional geochemical background level of total mercury was evaluated to calculate mercury contamination factors (Fc) in soils and river bottom sediments. Our estimate of the mean background mercury levels in river sediments and soils, not affected by human activities, was 232 ng g1 (range: 27–406 ng g1). Sediments contaminated by the effluent fro...

  13. WiBasin: basin management through an integrated platform

    OpenAIRE

    Llort Pavon, Xavier; Sánchez-Diezma Guijarro, Rafael; Sancho, David; Rodríguez, Álvaro; Berenguer Ferrer, Marc; Sempere Torres, Daniel

    2014-01-01

    In this work we present WiBasin, a cloud platform for basin and dam management. It includes different sources of precipitation (both observed and forecasted), integration over the catchment domain (to provide an aggregated value of potential rainfall accumulated over the basin) , and a complete dissemination environment (web-viewer, capability of issuing hazard warnings with configurable thresholds, SMS, mails, etc.)

  14. Using self-organizing maps to infill missing data in hydro-meteorological time series from the Logone catchment, Lake Chad basin.

    Science.gov (United States)

    Nkiaka, E; Nawaz, N R; Lovett, J C

    2016-07-01

    Hydro-meteorological data is an important asset that can enhance management of water resources. But existing data often contains gaps, leading to uncertainties and so compromising their use. Although many methods exist for infilling data gaps in hydro-meteorological time series, many of these methods require inputs from neighbouring stations, which are often not available, while other methods are computationally demanding. Computing techniques such as artificial intelligence can be used to address this challenge. Self-organizing maps (SOMs), which are a type of artificial neural network, were used for infilling gaps in a hydro-meteorological time series in a Sudano-Sahel catchment. The coefficients of determination obtained were all above 0.75 and 0.65 while the average topographic error was 0.008 and 0.02 for rainfall and river discharge time series, respectively. These results further indicate that SOMs are a robust and efficient method for infilling missing gaps in hydro-meteorological time series. PMID:27282595

  15. Evaluation of the impact of farming activity in the water quality in surface catchment areas in hydrographic basin from Mogi-Guacu and Pardo Rivers, Sao Paulo

    International Nuclear Information System (INIS)

    This study was performed in 10 small basins located in the Mogi-Guacu and Pardo Rivers, in the Northeastern area of Sao Paulo State. The land belonging of these basins is used to grow row crops of potato, coffee and pasture areas. This study aimed to characterize small basins, to evaluate water and sediment quality and to correlate basic aspects of climatology, hydrology, toxicology and land uses to the physical, chemical and toxicological characteristics of the water in the streams. Geographic Information System (GIS) was used as a tool of evaluation of land uses and risk assessment was performed for a final evaluation. The samplings were carried out from June/1999 to June/2000 in the 13 collecting points. It was verified that water quality is dependent upon the rainy and dry periods and the harvest periods. In the beginning of rainy periods were found large concentrations of metals and traces of herbicides leachate from soil and, in the dry period the same event was verified, caused by concentration of the water. In August, September and October phosphorus concentrations were very low getting an improvement in the water quality. Al, Fe and Mn are majority elements of chemical compositions of rocks of the study area, and exceed the Brazilian Guidelines. The stream waters were classified as 44% oligotrophic, 42% mesotrophic and 14% eutrophic. Jaguari-Mirim River presented the largest values of Trophic Index (TI). Sediment analyses showed a great variety of organic compounds coming from anthropogenic activities (industrial and farming activity). Toxicity tests with hyalella azteca in the sediments presented toxicity for sediments from Sao Joao da Boa Vista and Divinolandia. A methodology was developed for organochlorinated pesticides by gas chromatography coupled to mass spectrometry (GCMS). The presence of organochlorinated pesticides was not verified. (author)

  16. Runoff Responses to Forest Thinning at Plot and Catchment Scales in a Headwater Catchment Draining Japanese Cypress Forest

    Science.gov (United States)

    We examined the effect of forest thinning on runoff generation at plot and catchment scales in headwater basins draining a Japanese cypress (Chamaecyparis obtusa) forest. We removed 58.3% of the stems (corresponding to 43.2% of the basal area) in the treated headwater basin (catc...

  17. Co-evolution of volcanic catchments in Japan

    Science.gov (United States)

    Yoshida, T.; Troch, P. A. A.

    2015-12-01

    Present day landscapes have evolved over time through interactions between the prevailing climates and geological settings. Understanding the linkage between spatial patterns of landforms, soils, and vegetation in landscapes and their hydrological response is critical to make quantitative predictions in ungaged basins. Catchment co-evolution is a theoretical framework that seeks to formulate hypotheses about the mechanisms and conditions that determine the historical development of catchments and how such evolution affects their hydrological response. In this study, we selected 14 volcanic catchments of different ages (from 0.22 to 82Ma) in Japan. We derived indices of landscape properties (drainage density) as well as hydrological response (annual water balance, baseow index, and flow duration curves) and examined their relation with catchment age and climate (through the aridity index). We found signicant correlation between drainage density and baseow index with age, but not with climate. The age of the catchments was also signicantly related to intra-annual flow variability. Younger catchments tend to have lower peak flows and higher low flows, while older catchments exhibit more flashy runoff. The decrease of baseflow with catchment age confirms previous studies that hypothesized that in volcanic landscapes the major flow pathways have changed over time, from deep groundwater flow to shallow subsurface flow. The drainage density of our catchments decreased with age, contrary to previous findings in similar volcanic catchments but of signicant younger age than the ones explored here. In these younger catchments, an increase in drainage density with age was observed, and it was hypothesized that this was because of more landscape incision due to increasing near-surface lateral flow paths in more mature catchments. Our results suggest that as catchments further evolve, hydrologically active channels retreat as less recharge leads to lower average aquifer levels

  18. A multi-proxy lake core record from Lago Lungo, Rieti Basin, Lazio, Italy and its relation to human activities in the catchment during the last century

    Science.gov (United States)

    Noble, Paula; Tunno, Irene; Mensing, Scott; Piovesan, Gianluca

    2016-04-01

    The lakes of the Rieti Basin have experienced extensive human modification dating back to pre-Roman times, yet lake archives indicate that the most profound changes to the aquatic ecosystem have occurred during the last century. Analysis of the upper ˜120 cm segment of a sediment core from Lago Lungo, dating back to ˜1830 CE, show changes in water quality and hydrologic inflow largely attributed to 20th century reclamation and land use activities. Lago Lungo is a shallow, small, eutrophic, hard water lake situated in an intermontaine alluvial plain ˜90 km NE of Rome. It is one of several remnant lakes in a poorly drained wetland area fed by numerous springs. Reclamation activities over the last century have substantially altered the drainage network affecting water delivery to the lakes and their connectivity. There are 3 interesting signals in the core. First, small Stephanodiscus species, associated with hypereutrophic conditions, appear after 1950, peak ˜1990, and may be attributed to increased use of chemical fertilizers and intensification of local agriculture. Elemental proxies from scanning XRF data (abundances of Ti, Si/Ti, and Ca) are consistent with increased eutrophication starting ˜1950. A decline in Stephanodicsus after 1990 reflects some improvement to the water quality following the lake's incorporation into a nature preserve and creation of a narrow vegetation buffer. Intermittent water quality measurements from 1982 onward corroborate the changes in trophic status interpreted from the core record. Second, a large change in the core stratigraphy, elemental geochemistry, and diatom composition occurs ˜1940 and is associated with several major reclamation efforts, including the rerouting of the Santa Susanna channel, which redirected large volumes of artesian inflows away from the lakes and estuarine system. Upstream, dams on the Turano and Salto rivers were also constructed, further affecting hydrological inflows into the basin. From ˜1900

  19. Impact and sustainability of low-head drip irrigation kits, in the semi-arid Gwanda and Beitbridge Districts, Mzingwane Catchment, Limpopo Basin, Zimbabwe

    Science.gov (United States)

    Moyo, Richard; Love, David; Mul, Marloes; Mupangwa, Walter; Twomlow, Steve

    Resource-poor smallholder farmers in the semi-arid Gwanda and Beitbridge districts face food insecurity on an annual basis due to a combination of poor and erratic rainfall (average 500 mm/a and 345 mm/a, respectively, for the period 1970-2003) and technologies inappropriate to their resource status. This impacts on both household livelihoods and food security. In an attempt to improve food security in the catchment a number of drip kit distribution programmes have been initiated since 2003 as part of an on-going global initiative aimed at 2 million poor households per year. A number of recent studies have assessed the technical performance of the drip kits in-lab and in-field. In early 2005 a study was undertaken to assess the impacts and sustainability of the drip kit programme. Representatives of the NGOs, local government, traditional leadership and agricultural extension officers were interviewed. Focus group discussions with beneficiaries and other villagers were held at village level. A survey of 114 households was then conducted in two districts, using a questionnaire developed from the output of the interviews and focus group discussions. The results from the study showed that the NGOs did not specifically target the distribution of the drip kits to poor members of the community (defined for the purpose of the study as those not owning cattle). Poor households made up 54% of the beneficiaries. This poor targeting of vulnerable households could have been a result of conditions set by some implementing NGOs that beneficiaries must have an assured water source. On the other hand, only 2% of the beneficiaries had used the kit to produce the expected 5 harvests over the 2 years, owing to problems related to water shortage, access to water and also pests and diseases. About 51% of the respondents had produced at least 3 harvests and 86% produced at least 2 harvests. Due to water shortages during the dry season 61% of production with the drip kit occurred during

  20. Isotopic monitoring (2H, 18O) of the St. Lawrence and Ottawa rivers between 1997 and 2003- Links with interannual climatic variability and hydrological processes in their catchment basins

    Science.gov (United States)

    Myre, A.; Hillaire-Marcel, C.

    2004-05-01

    This study based on a water isotope (18O and 2H) monitoring of the St. Lawrence and Ottawa rivers (Canada) is a contribution to the international IAEA project: Isotopes tracing of hydrologic processes in large river basins [Gibson et al., 2002. EOS 83: 613 et p.]. Sampling of the St. Lawrence and Ottawa river waters started in 1997, on a biweekly to weekly basis. Monitoring stations are located at Montreal (i.e., at the outlet of the Great Lakes), Quebec City (the estuary of the St. Lawrence) and at the Carillon hydroelectric dam, near the outlet of a major tributary, the Ottawa River into the St. Lawrence itself. The goal of the study was to examine the seasonal and interannual variability of isotopic signatures of the St. Lawrence and Ottawa rivers, in relation notably with interannual climatic variations, and seasonal hydrologic processes in the watershed (summer evaporation, snowmelt, transit time of precipitation signals into runoff). Waters sampled at the three stations depict distinct isotopic compositions. At Montreal, relatively stable isotopic composition are observed with a mean weighted annual value of -54 % for 2H and -7.1 % for 18O. The Ottawa River water at Carillon also displays stable isotopic compositions but much lighter values (weighted mean annual values: -80 % for 2H and -10.8 % for 18O). Finally, isotopic compositions at Quebec City are intermediate between those of Montreal and Carillon, but show a much larger variability. They reflect mixing between the heavy isotope enriched Great Lakes water, the lighter water from the Ottawa River, and highly variable inputs from smaller tributaries (from the Laurentides and Appalachian mountains). The mean weighted isotopic compositions at Quebec City are -65 % and -8.6 %, respectively for 2H and 18O). Evaporative enrichment, in particular during low water level episodes, seem to be more important in the Ottawa River catchment than in the Great Lakes basin, based on a comparison of isotopic clusters at

  1. Debris-flow frequency and dynamics of an Alpine catchment during the past 150 years, the Schimbrig drainage basin, Central Switzerland

    Science.gov (United States)

    Savi, Sara; Bollschweiler, Michelle; Stoffel, Markus; Schlunegger, Fritz

    2010-05-01

    This paper focuses on links between landsliding and debris-flow activity in a ca. 4 km2-large drainage basin located at the northern foothills of the Central Swiss Alps. Debris-flow frequency of the recent past was reconstructed using dendrogeomorphic methods. In addition, the source area was mapped in detail to assess the spatial distribution of landslides, and to determine the connectivity between hillslopes and the channel network. The geomorphic map indicates that the hillslopes host abundant landslides sourced in Paleogene Flysch and Molasse sandstone-mudstone alternations. Major differences in the landscape architecture between the eastern and western sides were identified. In particular, the eastern segment is characterized by a >300'000 m2 large earth flow (Schimbrig landslide) that is 5-10 m deep. This flow experienced a phase of high slip rates >2m day-1 between September 1994 and May 1995, transferring a total of 350'000 m3 of material. In contrast, the western side is characterized by a network of deeply incised channels (>50 m) bordered by hillslopes that host landslides that generally measure trees obviously influenced by past debris-flow activity. Preliminary analysis of the tree samples indicate that 64% of the tree grew up between 1900 and 2009. 34% of the tree samples showed germination dates between 1800 and 1900, and the remaining 2% of the sampled specimens germinated before 1800. Dendrogeomorphic analyses depict that nearly 50% of the sampled trees were affected by debris-flow activity in the 1990s. This period of high activity might be related to enhanced sediment transfer to the river system in response to the high slip rates of the Schimbrig earth slide between 1994 and 1995. Other periods of enhanced debris-flows activity seem to have occurred around 1960, 1950, 1940 and at the end of 19th century.

  2. The hydrological regime of a forested tropical Andean catchment

    OpenAIRE

    Clark, K. E.; Torres, M. A.; West, A.J.; R. G. Hilton; New, M; Horwath, A. B.; J. B. Fisher; Rapp, J. M.; A. Robles Caceres; Y. Malhi

    2014-01-01

    The hydrology of tropical mountain catchments plays a central role in ecological function, geochemical and biogeochemical cycles, erosion and sediment production, and water supply in globally important environments. There have been few studies quantifying the seasonal and annual water budgets in the montane tropics, particularly in cloud forests. We investigated the water balance and hydrologic regime of the Kosñipata catchment (basin area: 164.4 km2) over the period 2010–20...

  3. River Styles, a Geomorphic Approach to Catchment Characterization: Implications for River Rehabilitation in Bega Catchment, New South Wales, Australia.

    Science.gov (United States)

    Brierley; Fryirs

    2000-06-01

    / Geomorphologically derived river styles provide an integrative framework for examining the interactions of biophysical processes in rivers throughout a drainage basin. Nine styles of river character and behavior are identified in Bega catchment, on the south coast of New South Wales, Australia. Headwater streams above the escarpment drain into gorges in the escarpment zone. In different subcatchments at the base of the escarpment, there are three different river styles, namely cut-and-fill, vertically accreted floodplains, and fans. Downstream of these river styles, in the rounded foothills of the catchment, throughput and transfer river styles convey sediments to the lowland plain. In one mid-catchment setting, a floodout traps sediment. Finally, along the lowland plain of Bega River, there is a floodplain accumulation river style. Downstream patterns of river styles in differing subcatchments of the Bega River basin are differentiated into three types, reflecting river adjustments to valley width, slope, and responses to human disturbance. Analysis of the character and condition of each river style in Bega catchment, and their downstream patterns, are used to provide a biophysical basis to prioritorize river management strategies. These reach-scale strategies are prioritorized within an integrative catchment framework. Conserving near-intact sections of the catchment is the first priority. Second, those parts of the catchment that have natural recovery potential are targeted. Finally, rehabilitation priorities are considered for highly degraded reaches. At these sites, erosion and sedimentation problems may reflect irreversible changes to river structure. PMID:10790530

  4. Water balance modeling of Upper Blue Nile catchments using a top-down approach

    NARCIS (Netherlands)

    Tekleab, S.; Uhlenbrook, S.; Mohamed, Y.; Savenije, H.H.G.; Temesgen, M.; Wenninger, J.

    2011-01-01

    The water balances of twenty catchments in the Upper Blue Nile basin have been analyzed using a top-down modeling approach based on Budyko’s hypotheses. The objective of this study is to obtain better understanding of water balance dynamics of upper Blue Nile catchments on annual and monthly time sc

  5. Co-evolution of volcanic catchments in Japan

    Directory of Open Access Journals (Sweden)

    T. Yoshida

    2015-09-01

    Full Text Available Present day landscapes have evolved over time through interactions between the prevailing climates and geological settings. Understanding the linkage between spatial patterns of landforms, soils, and vegetation in landscapes and their hydrological response is critical to make quantitative predictions in ungaged basins. Catchment co-evolution is a theoretical framework that seeks to formulate hypotheses about the mechanisms and conditions that determine the historical development of catchments and how such evolution affects their hydrological response. In this study, we selected 14 volcanic catchments of different ages (from 0.225 to 82.2 Ma in Japan. We derived indices of landscape properties (drainage density as well as hydrological response (annual water balance, baseflow index, and flow duration curves and examined their relation with catchment age and climate (through the aridity index. We found significant correlation between drainage density and baseflow index with age, but not with climate. The age of the catchments was also significantly related to intra-annual flow variability. Younger catchments tend to have lower peak flows and higher low flows, while older catchments exhibit more flashy runoff. The decrease of baseflow with catchment age confirms previous studies that hypothesized that in volcanic landscapes the major flow pathways have changed over time, from deep groundwater flow to shallow subsurface flow. The drainage density of our catchments decreased with age, contrary to previous findings in similar volcanic catchments but of significant younger age than the ones explored here. In these younger catchments, an increase in drainage density with age was observed, and it was hypothesized that this was because of more landscape incision due to increasing near-surface lateral flow paths in more mature catchments. Our results suggests two hypotheses on the evolution of drainage density in matured catchments. One is that as

  6. The Storage Dynamics of a Subarctic Canadian Shield Catchment

    Science.gov (United States)

    Spence, C.; Hedstrom, N.; Granger, R.; Reid, B.

    2008-12-01

    Several previous studies have identified the importance of exceeding storage thresholds for generating runoff from components of the Canadian Shield landscape. A water budget study was initiated in the 150 square kilometer Baker Creek research catchment in the subarctic Canadian Shield to evaluate the significance of storage, its dynamic and potential influence on runoff generation at a catchment scale. Water budget measurements taken from April - September 2007 included precipitation, snowmelt, terrestrial evapotranspiration, lake evaporation, streamflow, lake detention storage and soil water storage. Most of the snowmelt is directed to storage early in the study period, with much of the remainder directed to streamflow. Contrary to expectations, the largest storage receptacle was not the lakes, but the soils. Losses to the atmosphere from storage dominated the fluxes from the catchment by the end of June. A geophysically based investigative framework shows that streamflow at the catchment outlet displays a hysteretic relationship with storage. The efficiency with which storage is converted to streamflow during individual runoff events increased non-linearly with the ratio of precipitation inputs to a weighted basin scale storage deficit. The non linear pattern can be explained by differences in the locations and nature of the areas hydrologically connected to the outlet among events. When the catchment is dry, only a series of large lakes contribute to runoff to the basin outlet. When the catchment is wet, much more of the watershed can direct water to the outlet, and the basin becomes more efficient in generating runoff. Furthermore, low water levels associated with dry conditions reduce the efficiency with which water can be transferred downstream by the lakes. The results imply that the probability distribution of distance to the outlet from locations where storage thresholds have been exceeded may be useful in discerning the runoff ratio in heterogeneous

  7. Land use and land use dynamics in the upper-Ruizi river catchment, Southwestern Uganda

    OpenAIRE

    Vanonckelen, Steven; Isabirye, Moses; Deckers, Seppe; Poesen, Jean

    2011-01-01

    In the effort to assess the land uses and land use dynamics in the Lake Victoria basin, a field survey is carried out in the Ruizi river catchment, Southwestern Uganda. The catchment plays a crucial role in the food production of the entire country and it is probably a major contributor of water and sediment to Lake Victoria. A land use map of relevant sub-catchments is constructed by field visits and GPS mapping. The land use dynamics are researched in two micro-catchments by compari...

  8. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: Nutrient Inputs from Fertilizer and Manure, Nitrogen and Phosphorus (N&P), 2002

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents the total amount of nitrogen and phosphorus, in kilograms for the year 2002, compiled for every MRB_E2RF1 catchment of the Major...

  9. Some relationships between lithology, basin form and hydrology : a case study from the Thames Basin, UK

    OpenAIRE

    Bloomfield, J. P.; S. H. Bricker; Newell, A. J.

    2011-01-01

    The role of lithology in influencing basin form and function is explored empirically by investigating correlations between a range of catchment variables, where the spatial unit of analysis is not surface catchments but lithologically coherent groundwater units. Using the Thames basin, UK, as a case study, nine groundwater units have been identified. Values for 11 hydrological and geomorphological variables, including rainfall, drainage density, Baseflow Index, aquifer porosity, storage coeff...

  10. Study of Beijiang catchment flash-flood forecasting model

    Science.gov (United States)

    Chen, Y.; Li, J.; Huang, S.; Dong, Y.

    2015-05-01

    Beijiang catchment is a small catchment in southern China locating in the centre of the storm areas of the Pearl River Basin. Flash flooding in Beijiang catchment is a frequently observed disaster that caused direct damages to human beings and their properties. Flood forecasting is the most effective method for mitigating flash floods, the goal of this paper is to develop the flash flood forecasting model for Beijiang catchment. The catchment property data, including DEM, land cover types and soil types, which will be used for model construction and parameter determination, are downloaded from the website freely. Based on the Liuxihe Model, a physically based distributed hydrological model, a model for flash flood forecasting of Beijiang catchment is set up. The model derives the model parameters from the terrain properties, and further optimized with the observed flooding process, which improves the model performance. The model is validated with a few observed floods occurred in recent years, and the results show that the model is reliable and is promising for flash flood forecasting.

  11. Empirical relations between catchment characteristics and discharge patterns in Sweden

    Science.gov (United States)

    Lindström, G.; Dahné, J.; Arheimer, B.

    2012-04-01

    In hydrological modelling it is often assumed that catchment characteristics, such as soil type, vegetation, land-use, slope, altitude and climate influence both the magnitude and dynamics of the water discharge characteristics. This presentation demonstrates an inter-site comparison on similarities and dissimilarities in hydrological response from Swedish unregulated catchments with an area less than 2000 km2. Observed daily time-series for about 20 years from 198 sites were analysed to search for and quantify statistical relationships between catchment characteristics and flow characteristics. A number of flow characteristics were calculated, such as the mean, mean annual maximum, peakiness, skewness and percentiles. The catchments were grouped dependent on catchment characteristics (for example >80% forest). The differences between the discharges from different catchment types were analysed both graphically and statistically. A T-test was performed to see if the mean value for the flow characteristics was significantly different from the rest of the catchments. Following the t-test, a set of box-whisker diagrams were made for visual inspection of the results. The results showed that lake percentage is the most important catchment characteristic for most of the flow characteristics. The effect of lakes was therefore treated separately. For lake-free basins soil type was in general more important than land-use. For instance, coarse soils exhibit a sustained base flow, whereas thin soils and bare rock are characterised by peak flows with short duration. Finally, the presentation will give some examples on how the retrieved empirical information was included in a national modelling approach to simulate spatial variability in Swedish water discharge patterns.

  12. Hydrologic comparison between a lowland catchment (Kielstau, Germany and a mountainous catchment (XitaoXi, China using KIDS model in PCRaster

    Directory of Open Access Journals (Sweden)

    N. Fohrer

    2009-08-01

    Full Text Available The KIDS model (Kielstau Discharge Simulation model is a simple rainfall-runoff model developed originally for the Kielstau catchment. To extend its range of application we applied it to a completely different catchment, the XitaoXi catchment in China. Kielstau is a small (51 km2 lowland basin in Northern Germany, with large proportion of wetland area. And XitaoXi is a mesoscale (2271 km2 mountainous basin in the south of China. Both catchments differ greatly in size, topography, landuse, soil properties, and weather conditions. We compared two catchments in these features and stress on the analysis how the specific catchment characteristics could guide the adaptation of KIDS model and the parameter estimation for streamflow simulation. The Nash and Sutcliffe coefficient was 0.73 for Kielstau and 0.65 for XitaoXi. The results suggest that the application of KIDS model may require adjustments according to the specific physical background of the study basin.

  13. Creating a catchment perspective for river restoration

    Directory of Open Access Journals (Sweden)

    L. Benda

    2011-03-01

    Full Text Available One of the major challenges in river restoration is to identify the natural fluvial landscape in catchments with a long history of river control. Intensive land use on valley floors often predates the earliest remote sensing: levees, dikes, dams, and other structures alter valley-floor morphology, river channels and flow regimes. Consequently, morphological patterns indicative of the fluvial landscape including multiple channels, extensive floodplains, wetlands, and fluvial-riparian and tributary-confluence dynamics can be obscured, and information to develop appropriate and cost effective river restoration strategies can be unavailable. This is the case in the Pas River catchment in northern Spain (650 km2, in which land use and development have obscured the natural fluvial landscape in many parts of the basin. To address this issue we coupled general principles of hydro-geomorphic processes with computer tools to characterize the fluvial landscape. Using a 5-m digital elevation model, valley-floor surfaces were mapped according to elevation above the channel and proximity to key geomorphic processes. The predicted fluvial landscape is patchily distributed according to topography, valley morphology, river network structure, and fan and terrace landforms. The vast majority of the fluvial landscape in the main segments of the Pas River catchment is presently masked by human infrastructure, with only 15% not impacted by river control structures and development. The reconstructed fluvial landscape provides a catchment scale context to support restoration planning, in which areas of potential ecological productivity and diversity could be targeted for in-channel, floodplain and riparian restoration projects.

  14. A methodological comparison of catchment storages in mountainous catchments

    Science.gov (United States)

    Weiler, Markus; Staudinger, Maria; Stölzle, Michael; Seeger, Stefan; Seibert, Jan; Stahl, Kerstin

    2015-04-01

    One of the most important functions of catchments is the temporary storage of water, which directly influences runoff dynamics, rainfall-runoff transformation, partitioning of evaporation and runoff fluxes, and accessibility of water to plants. Generally, a large catchment storage is considered beneficial and in particular increases the transit times and hence the buffer functioning related to water quality. Many different methods have been developed to assess catchment storage, however, there are hardly any direct comparisons of several of these methods. One challenge is the definition of water storage, while some methods allow estimation of the entire water storage in a catchment, other methods quantify only the dynamic storage. In addition, most studies focused more on lowland catchments with rain-dominated runoff regimes and observed groundwater fluctuations. Furthermore, these studies often focus on one or two catchments, but do not consider the influence of different climates on the relevance of water storage in the catchment. We applied a range of different methods to assess catchment storage characteristics in 18 catchments in the Swiss Alps, ranging from 500 to 2000m of mean elevation and hence from rainfall- to snowmelt dominated runoff regimes. The first method use only discharge information during recession periods and with varying approaches to extract discharge and storage changes between high flow and low flow, the dynamic catchment storage can be derived. In the next methods the conceptual hydrological model HBV is calibrated to the runoff dynamics and the dynamic and total catchment storages of the different compartments are being evaluated. The last methods are based on stable water isotope data analysis. We use the model TRANSEP to derive the dynamic storage as well as the total water storage of the catchment based on the transit times using several years of fortnightly isotope data in streamflow. The results show that the derived catchment

  15. Catchment controls on solute export

    Science.gov (United States)

    Musolff, Andreas; Schmidt, Christian; Selle, Benny; Fleckenstein, Jan H.

    2015-12-01

    Dynamics of solute export from catchments can be classified in terms of chemostatic and chemodynamic export regimes by an analysis of concentration-discharge relationships. Previous studies hypothesized that distinct export regimes emerge from the presence of solute mass stores within the catchment and their connectivity to the stream. However, so far a direct link of solute export to identifiable catchment characteristics is missing. Here we investigate long-term time series of stream water quality and quantity of nine neighboring catchments in Central Germany ranging from relatively pristine mountain catchments to agriculturally dominated lowland catchments, spanning large gradients in land use, geology, and climatic conditions. Given the strong collinearity of catchment characteristics we used partial least square regression analysis to quantify the predictive power of these characteristics for median concentrations and the metrics of export regime. We can show that median concentrations and metrics of the export regimes of major ions and nutrients can indeed be inferred from catchment characteristics. Strongest predictors for median concentrations were the share of arable land, discharge per area, runoff coefficient and available water capacity in the root zone of the catchments. The available water capacity in the root zone, the share of arable land being artificially drained and the topographic gradient were found to be the most relevant predictors for the metrics of export regime. These catchment characteristics can represent the size of solute mass store such as the fraction of arable land being a measure for the store of nitrate. On the other hand, catchment characteristics can be a measure for the connectivity of these solute stores to the stream such as the fraction of tile drained land in the catchments. This study demonstrates the potential of data-driven, top down analyses using simple metrics to classify and better understand dominant controls of

  16. Equitable water allocation in a heavily committed international catchment area: the case of the Komati Catchment

    Science.gov (United States)

    Nkomo, Sakhiwe; van der Zaag, Pieter

    This paper investigates water availability and use in the Komati catchment. The Komati catchment is shared by Swaziland and South Africa and forms part of the Incomati basin, with Mozambique as the third riparian country. In 2002 the three countries reached agreement about how the scarce water should be allocated, based on the principle of equitable and sustainable utilization, as stipulated by the SADC Protocol. The Komati catchment has five main water uses: afforestation, irrigation, the environment, urban/industrial/mining (UIM), and interbasin water transfers (for industrial use). In addition, South Africa and Swaziland have committed themselves to satisfy a certain cross border flow to downstream Mozambique. Frequently, debate has arisen between users and riparian countries on the direction that water resources development has taken in the catchment. Downstream farmers have often complained about interbasin transfers taking place in the upstream portions of the catchment. There has also been animosity about effecting environmental flow releases. A relatively simple, spreadsheet-based water resources model (Waflex) was developed to analyse water availability and use under current and future scenarios. The results were then compared to results obtained from another model that was used in a joint study by Mozambique, South Africa and Swaziland. The Waflex model showed a high degree of consistency with the one used for comparison, especially in terms of trends. It was found that the recent completion of two new dams has improved water supply to irrigation in the two countries. Future water demands will result in appreciable shortages for irrigation and domestic use. The agreed maximum development levels will soon outstrip the ability of the catchment’s supply. The paper shows that a combination of measures will be required to ensure equitable and sustainable water utilisation in the Komati catchment. These will have to be agreed by the riparian countries

  17. Climate change and catchment hydrology

    OpenAIRE

    Murphy, Conor

    2013-01-01

    Climate change is expected to alter catchment hydrology through changes in extremes of flooding and drought. River catchments are complex, dynamic systems and it is important to develop our understanding of how these systems are likely to respond to changes in climate. Work is ongoing in using EC-Earth simulations to further our understanding of how climate change will affect catchment hydrology and flood risk. In Ireland, the importance of this task is emphasised ...

  18. Socio-hydrological water balance for water allocation between human and environmental purposes in catchments

    OpenAIRE

    Zhou, S.; Y. HUANG; Wei, Y.; Wang, G

    2015-01-01

    Rebalancing water allocation between human consumptive uses and the environment in water catchments is a global challenge. This paper proposes a socio-hydrological water balance framework by partitioning catchment total evapotranspiration (ET) into ET for society and ET for natural ecological systems, and establishing the linkage between the changes of water balance and its social drivers and resulting environmental consequences in the Murray–Darling Basin (MDB), Australia, ...

  19. SOILS VULNERABILITY OF CATCHMENT ALMAŞ AT GEOMORPHOLOGIC CONTEMPORARY PROCESSES

    OpenAIRE

    MĂDĂLINA-IOANA RUS; I. A. IRIMUȘ

    2015-01-01

    Soils vulnerability of the Catchment Almas geomorphologic processes. Almas Basin, signed lower lithologic Miocene soils deposits, shows six classes: Cernisols, Cambisols, Luvisols, Hydrosols, Pelisols, Protosols (after SRTS, 2003). The largest share is attributed to Luvisols class (60%), followed by undeveloped soil represented by Protosols and Antrisols (15%), followed by the remaining classes with lower weights: Cambisols (13%), Cernisols (7%), Pelisols (4%), Hydrosols (1%). Contemporary ge...

  20. Hydrological Catchment Similarity Assessment in Geum River Catchments, Korea

    Science.gov (United States)

    Ko, Ara; Park, Kisoon; Lee, Hyosang

    2013-04-01

    Similarity measure of catchments is essential for regionalization studies, which provide in depth analysis in hydrological response and flood estimations at ungauged catchments. However, this similarity measure is often biased to the selected catchments and is notclearly explained in hydrological sense. This study applied a type of hydrological similarity distance measure-Flood Estimation Handbook to 25 Geum river catchments, Korea. Three Catchment Characteristics, Area (A)-Annual precipitation (SAAR)-SCS Curve Number (CN), are used in Euclidian distance measures. Furthermore, six index of Flow Duration Curve (ILow:Q275/Q185, IDrought:Q355/Q185, IFlood:Qmax/Q185, IAbundant:Q95/Q185, IFloodDuration:Q10/Q355 and IRiverRegime:Qmax/Qmin) are applied to clustering analysis of SPSS. The catchments' grouping of hydrological similarity measures suggests three groups: H1 (Cheongseong, Gidae, Bukil, Oksan, Seockhwa, Habgang and Sangyeogyo), H2 (Cheongju, Guryong, Ugon, Boksu, Useong and Seokdong) and H3 (Muju, Yangganggyo and YongdamDam). The four catchments (Cheoncheon, Donghyang, DaecheongDam and Indong) are not grouped in this study. The clustering analysis of FDC provides four Groups; CFDC1 (Muju, YongdamDam, Yangganggyo, DaecheongDam, Cheongseong, Gidae, Seokhwa, Bukil, Habgang, Cheongju, Oksan, Yuseong and Guryong), CFDC2 (Cheoncheon, Donghyang, Boksu, Indong, Nonsan, Seokdong, Ugon, Simcheon, Useong and Sangyeogyo), CFDC3 (Songcheon) and CFDC4 (Tanbu). The six catchments (out of seven) of H1 are grouped in CFDC1, while Sangyeogyo is grouped in CFDC2. The four catchments (out of six) of H2 are also grouped in CFDC2, while Cheongju and Guryong are grouped in CFDC1. The catchments of H3 are categorized in CFDC1. The authors examine the results (H1, H2 and H3) of similarity measure based on catchment physical descriptors with results (CFDC1 and CFDC2) of clustering based on catchment hydrological response. The results of hydrological similarity measures are supported by

  1. THE FORMATION OF THE OUTFLOW IN THE URBANISED CATCHMENT AREA ON THE EXAMPLE OF THE CATCHMENT OF STRZYŻA

    OpenAIRE

    Magda Sikora; Roman Cieśliński

    2015-01-01

    The aim of the study is to determine what influence made various forms of land use of catchment area on the size and variability of the outflow. Linking the flow rate with the forms of land use will determine which factors affect the runoff in the basin. The object of the research is Strzyża river basin situated within the administrative boundaries of the city of Gdańsk. It was found that streams flowing through urban areas, including the city of Gdańsk (river Strzyża), quickly react to any e...

  2. Environmental care in agricultural catchments: Toward the communicative catchment

    Science.gov (United States)

    Martin, Peter

    1991-11-01

    Substantial land degradation of agricultural catchments in Australia has resulted from the importation of European farming methods and the large-scale clearing of land. Rural communities are now being encouraged by government to take responsibility for environmental care. The importance of community involvement is supported by the view that environmental problems are a function of interactions between people and their environment. It is suggested that the commonly held view that community groups cannot care for their resources is due to inappropriate social institutions rather that any inherent disability in people. The communicative catchment is developed as a vision for environmental care into the future. This concept emerges from a critique of resource management through the catchment metaphors of the reduced, mechanical, and the complex, evolving catchment, which reflect the development of systemic and people-centered approaches to environmental care. The communicative catchment is one where both community and resource managers participate collaboratively in environmental care. A methodology based on action research and systemic thinking (systemic action research) is proposed as a way of moving towards the communicative catchment of the future. Action research is a way of taking action in organizations and communities that is participative and informed by theory, while systemic thinking takes into account the interconnections and relationships between social and natural worlds. The proposed vision, methodology, and practical operating principles stem from involvement in an action research project looking at extension strategies for the implementation of total catchment management in the Hunter Valley, New South Wales.

  3. Adaptation of the Integrated Nitrogen Model for Catchments (INCA to seasonally snow-covered catchments

    Directory of Open Access Journals (Sweden)

    K. Rankinen

    2004-01-01

    Full Text Available Testing of the Integrated Nitrogen model for Catchments (INCA in a wide range of ecosystem types across Europe has shown that the model underestimates N transformation processes to a large extent in northern catchments of Finland and Norway in winter and spring. It is found, and generally assumed, that microbial activity in soils proceeds at low rates at northern latitudes during winter, even at sub-zero temperatures. The INCA model was modified to improve the simulation of N transformation rates in northern catchments, characterised by cold climates and extensive snow accumulation and insulation in winter, by introducing an empirical function to simulate soil temperatures below the seasonal snow pack, and a degree-day model to calculate the depth of the snow pack. The proposed snow-correction factor improved the simulation of soil temperatures at Finnish and Norwegian field sites in winter, although soil temperature was still underestimated during periods with a thin snow cover. Finally, a comparison between the modified INCA version (v.1.7 and the former version (v.1.6 was made at the Simojoki river basin in northern Finland and at Dalelva Brook in northern Norway. The new modules did not imply any significant changes in simulated NO3- concentration levels in the streams but improved the timing of simulated higher concentrations. The inclusion of a modified temperature response function and an empirical snow-correction factor improved the flexibility and applicability of the model for climate effect studies. Keywords: inorganic N leaching, degree-day snow model, snow pack, catchment scale model

  4. Defining prior probabilities for hydrologic model structures in UK catchments

    Science.gov (United States)

    Clements, Michiel; Pianosi, Francesca; Wagener, Thorsten; Coxon, Gemma; Freer, Jim; Booij, Martijn

    2014-05-01

    The selection of a model structure is an essential part of the hydrological modelling process. Recently flexible modeling frameworks have been proposed where hybrid model structures can be obtained by mixing together components from a suite of existing hydrological models. When sufficient and reliable data are available, this framework can be successfully utilised to identify the most appropriate structure, and associated optimal parameters, for a given catchment by maximizing the different models ability to reproduce the desired range of flow behaviour. In this study, we use a flexible modelling framework to address a rather different question: can the most appropriate model structure be inferred a priori (i.e without using flow observations) from catchment characteristics like topography, geology, land use, and climate? Furthermore and more generally, can we define priori probabilities of different model structures as a function of catchment characteristics? To address these questions we propose a two-step methodology and demonstrate it by application to a national database of meteo-hydrological data and catchment characteristics for 89 catchments across the UK. In the first step, each catchment is associated with its most appropriate model structure. We consider six possible structures obtained by combining two soil moisture accounting components widely used in the UK (Penman and PDM) and three different flow routing modules (linear, parallel, leaky). We measure the suitability of a model structure by the probability of finding behavioural parameterizations for that model structure when applied to the catchment under study. In the second step, we use regression analysis to establish a relation between selected model structures and the catchment characteristics. Specifically, we apply Classification And Regression Trees (CART) and show that three catchment characteristics, the Base Flow Index, the Runoff Coefficient and the mean Drainage Path Slope, can be used

  5. Evaluating stream water quality through land use analysis in two grassland catchments: impact of wetlands on stream nitrogen concentration.

    Science.gov (United States)

    Hayakawa, A; Shimizu, M; Woli, K P; Kuramochi, K; Hatano, R

    2006-01-01

    We evaluated the impacts of natural wetlands and various land uses on stream nitrogen concentration in two grassland-dominated catchments in eastern Hokkaido, Japan. Analyzing land use types in drainage basins, measuring denitrification potential of its soil, and water sampling in all seasons of 2003 were performed. Results showed a highly significant positive correlation between the concentration of stream NO3-N and the proportion of upland area in drainage basins in both catchments. The regression slope, which we assumed to reflect the impact on water quality, was 24% lower for the Akkeshi catchment (0.012 +/- 0.001) than for the Shibetsu catchment (0.016 +/- 0.001). In the Akkeshi catchment, there was a significant negative correlation between the proportion of wetlands in the drainage basins and stream NO3-N concentration. Stream dissolved organic nitrogen (DON) and carbon (DOC) concentrations were significantly higher in the Akkeshi catchment. Upland and urban land uses were strongly linked to increases in in-stream N concentrations in both catchments, whereas wetlands and forests tended to mitigate water quality degradation. The denitrification potential of the soils was highest in wetlands, medium in riparian forests, and lowest in grasslands; and was significant in wetlands and riparian forests in the Akkeshi catchment. The solubility of soil organic carbon (SOC) and soil moisture tended to determine the denitrification potential. These results indicate that the water environment within the catchments, which influences denitrification potential and soil organic matter content, could have caused the difference in stream water quality between the two catchments. PMID:16510707

  6. The catchment based approach using catchment system engineering

    Science.gov (United States)

    Jonczyk, Jennine; Quinn, Paul; Barber, Nicholas; Wilkinson, Mark

    2015-04-01

    The catchment based approach (CaBa) has been championed as a potential mechanism for delivery of environmental directives such as the Water Framework Directive in the UK. However, since its launch in 2013, there has been only limited progress towards achieving sustainable, holistic management, with only a few of examples of good practice ( e.g. from the Tyne Rivers trust). Common issues with developing catchment plans over a national scale include limited data and resources to identify issues and source of those issues, how to systematically identify suitable locations for measures or suites of measures that will have the biggest downstream impact and how to overcome barriers for implementing solutions. Catchment System Engineering (CSE) is an interventionist approach to altering the catchment scale runoff regime through the manipulation of hydrological flow pathways throughout the catchment. A significant component of the runoff generation can be managed by targeting hydrological flow pathways at source, such as overland flow, field drain and ditch function, greatly reducing erosive soil losses. Coupled with management of farm nutrients at source, many runoff attenuation features or measures can be co-located to achieve benefits for water quality and biodiversity. A catchment, community-led mitigation measures plan using the CSE approach will be presented from a catchment in Northumberland, Northern England that demonstrate a generic framework for identification of multi-purpose features that slow, store and filter runoff at strategic locations in the landscape. Measures include within-field barriers, edge of field traps and within-ditch measures. Progress on the implementation of measures will be reported alongside potential impacts on the runoff regime at both local and catchment scale and costs.

  7. A simple distributed sediment delivery approach for rural catchments

    Science.gov (United States)

    Reid, Lucas; Scherer, Ulrike

    2014-05-01

    The transfer of sediments from source areas to surface waters is a complex process. In process based erosion models sediment input is thus quantified by representing all relevant sub processes such as detachment, transport and deposition of sediment particles along the flow path to the river. A successful application of these models requires, however, a large amount of spatially highly resolved data on physical catchment characteristics, which is only available for a few, well examined small catchments. For the lack of appropriate models, the empirical Universal Soil Loss Equation (USLE) is widely applied to quantify the sediment production in meso to large scale basins. As the USLE provides long-term mean soil loss rates, it is often combined with spatially lumped models to estimate the sediment delivery ratio (SDR). In these models, the SDR is related to data on morphological characteristics of the catchment such as average local relief, drainage density, proportion of depressions or soil texture. Some approaches include the relative distance between sediment source areas and the river channels. However, several studies showed that spatially lumped parameters describing the morphological characteristics are only of limited value to represent the factors of influence on sediment transport at the catchment scale. Sediment delivery is controlled by the location of the sediment source areas in the catchment and the morphology along the flow path to the surface water bodies. This complex interaction of spatially varied physiographic characteristics cannot be adequately represented by lumped morphological parameters. The objective of this study is to develop a simple but spatially distributed approach to quantify the sediment delivery ratio by considering the characteristics of the flow paths in a catchment. We selected a small catchment located in in an intensively cultivated loess region in Southwest Germany as study area for the development of the SDR approach. The

  8. Catchment-scale biogeography of riverine bacterioplankton.

    Science.gov (United States)

    Read, Daniel S; Gweon, Hyun S; Bowes, Michael J; Newbold, Lindsay K; Field, Dawn; Bailey, Mark J; Griffiths, Robert I

    2015-02-01

    Lotic ecosystems such as rivers and streams are unique in that they represent a continuum of both space and time during the transition from headwaters to the river mouth. As microbes have very different controls over their ecology, distribution and dispersion compared with macrobiota, we wished to explore biogeographical patterns within a river catchment and uncover the major drivers structuring bacterioplankton communities. Water samples collected across the River Thames Basin, UK, covering the transition from headwater tributaries to the lower reaches of the main river channel were characterised using 16S rRNA gene pyrosequencing. This approach revealed an ecological succession in the bacterial community composition along the river continuum, moving from a community dominated by Bacteroidetes in the headwaters to Actinobacteria-dominated downstream. Location of the sampling point in the river network (measured as the cumulative water channel distance upstream) was found to be the most predictive spatial feature; inferring that ecological processes pertaining to temporal community succession are of prime importance in driving the assemblages of riverine bacterioplankton communities. A decrease in bacterial activity rates and an increase in the abundance of low nucleic acid bacteria relative to high nucleic acid bacteria were found to correspond with these downstream changes in community structure, suggesting corresponding functional changes. Our findings show that bacterial communities across the Thames basin exhibit an ecological succession along the river continuum, and that this is primarily driven by water residence time rather than the physico-chemical status of the river. PMID:25238398

  9. 巢湖流域丰乐河洪水事件营养盐输出动态研究%DYNAMIC EVOLUTION OF NUTRIENT EXPORT DURING FLOOD EVENTS FROM FENGLE RIVER CATCHMENT OF CHAO LAKE BASIN,CHINA

    Institute of Scientific and Technical Information of China (English)

    储茵; 潮洪武; 马友华; 郑珊珊; 潘应生

    2013-01-01

    洪水期是非点源污染输出的关键时期.通过对巢湖典型农业型流域丰乐河桃溪断面两次暴雨洪水过程(发生于2010年6月初的Event06和8月底的Event08)进行集中取样监测,结合该断面流量数据,分析了洪水过程中氮和磷营养盐不同指标(包括总氮、铵氮、硝态氮、总磷和可溶磷)浓度和瞬时负荷的动态变化规律.结果表明:Event06氮磷各指标浓度最小值、最大值及平均值均比Event08大,这与6月初农作物大量施肥,氮磷来源丰富有很大关系.丰乐河洪水事件氮输出的形式以可溶性无机氮(铵氮和硝态氮)为主,而磷则以颗粒态为主,但在涨水段的初、中期颗粒态氮和颗粒态磷所占比例比其它时段高.洪水过程中主要氮、磷指标浓度和瞬时负荷随流量增大而总体呈上升趋势(除了硝态氮),在流量峰值前达到最大值,然后呈总体下降趋势.总磷、总氮浓度与流量呈比较典型的顺时针圈形结构,表明暴雨洪水较强烈的冲刷输送作用.虽然进一步的负荷累积分析并没有显示显著的初期冲刷效应,但洪水期,特别是涨水段营养盐输出的重要性已较明显.丰乐河流域面积较大、地势较平坦,以农业活动为主,水体污染的非点源来源与农业活动有关,具体的洪水过程对营养盐的输出动态也有一定影响.%Non-point source pollutants are mainly transported during flood events.The Fengle River,one of the main tributaries of the Chao Lake in the middle-east part of China,was chosen to study non-point source nutrient export characteristics in a large-sized agricultural catchment.Two summer events (Event06,in the beginning of June and Event08,at the end of August,2010) were intensively sampled at Taoxi section of the river and analyzed for Total Nitrogen (TN),Ammonia,Nitrate,Total Phosphorus (TP) and Dissolved Phosphorus.Hourly discharge and rainfall data were also available at the same section.The drainage

  10. Use of remote sensing for hydrological parameterisation of Alpine catchments

    Directory of Open Access Journals (Sweden)

    H. Bach

    2003-01-01

    Full Text Available Physically-based water balance models require a realistic parameterisation of land surface characteristics of a catchment. Alpine areas are very complex with strong topographically-induced gradients of environmental conditions, which makes the hydrological parameterisation of Alpine catchments difficult. Within a few kilometres the water balance of a region (mountain peak or valley can differ completely. Hence, remote sensing is invaluable for retrieving hydrologically relevant land surface parameters. The assimilation of the retrieved information into the water balance model PROMET is demonstrated for the Toce basin in Piemonte/Northern Italy. In addition to land use, albedos and leaf area indices were derived from LANDSAT-TM imagery. Runoff, modelled by a water balance approach, agreed well with observations without calibration of the hydrological model. Keywords: PROMET, fuzzy logic based land use classification, albedo, leaf area index

  11. Using isotope, hydrochemical methods and energy-balance modelling to estimate contribution of different components to flow forming process in a high-altitude catchment (Dzhancuat river basin case study)

    Science.gov (United States)

    Rets, Ekaterina; Loshakova, Nadezhda; Chizhova, Julia; Kireeva, Maria; Frolova, Natalia; Tokarev, Igor; Budantseva, Nadine; Vasilchuk, Yurij

    2016-04-01

    A multicomponent structure of sources of river runoff formation is characteristic of high-altitude territories: ice and firn melting; seasonal snow melting on glacier covered and non-glacier area of a watershed; liquid precipitation; underground waters. In addition, each of these components can run off the watershed surface in different ways. Use of isotopic, hydrochemical methods and energy balance modelling provides possibility to estimate contribution of different components to river runoff that is an essential to understand the mechanism of flow formation in mountainious areas. A study was carried out for Dzhancuat river basin that was chosen as representative for North Caucasus in course of the International Hydrological Decade. Complex glaciological, hydrological and meteorological observation have been carried in the basin since 1965. In years 2013-2015 the program also included daily collecting of water samples on natural stable isotopes on the Dzhancuat river gauging station, and sampling water nourishment sources (ice, snow, firn, liquid precipitation) within the study area. More then 800 water samples were collected. Application of an energy balance model of snow and ice melt with distributed parameters provided an opportunity to identify Dzhancuat river runoff respond to glaciers melt regime and seasonal redistribution of melt water. The diurnal amplitude of oscillation of the Dzhakuat river runoff in the days without precipitation is formed by melting at almost snow-free areas of the Dzhancuat glacier tongues. Snowmelt water from the non-glacierized part contributes to the formation of the next day runoff. A wave of snow and firn melt in upper zones of glacier flattens considerably during filtration through snow and run-off over the surface and in the body of the glacier. This determines a general significant inertia of the Dzhacuat river runoff. Some part of melt water is stored into natural regulating reservoirs of the watershed that supply the

  12. Transit times of water particles in the vadose zone across catchment states and catchments functional units

    Science.gov (United States)

    Sprenger, Matthias; Weiler, Markus

    2014-05-01

    Understanding the water movement in the vadose zone and its associated transport of solutes are of major interest to reduce nutrient leaching, pollution transport or other risks to water quality. Soil physical models are widely used to asses such transport processes, while the site specific parameterization of these models remains challenging. Inverse modeling is a common method to adjust the soil physical parameters in a way that the observed water movement or soil water dynamics are reproduced by the simulation. We have shown that the pore water stable isotope concentration can serve as an additional fitting target to simulate the solute transport and water balance in the unsaturated zone. In the presented study, the Mualem- van Genuchten parameters for the Richards equation and diffusivity parameter for the convection-dispersion equation have been parameterized using the inverse model approach with Hydrus-1D for 46 experimental sites of different land use, topography, pedology and geology in the Attert basin in Luxembourg. With the best parameter set we simulated the transport of a conservative solute that was introduced via a pulse input at different points in time. Thus, the transit times in the upper 2 m of the soil for different catchment states could be inferred for each location. It has been shown that the time a particle needs to pass the -2 m depth plane highly varies from the systems state and the systems forcing during and after infiltration of that particle. Differences in transit times among the study sites within the Attert basin were investigated with regards to its governing factors to test the concept of functional units. The study shows the potential of pore water stable isotope concentration for residence times and transport analyses in the unsaturated zone leading to a better understanding of the time variable subsurface processes across the catchment.

  13. Climate-vegetation-soil interactions and long-term hydrologic partitioning: signatures of catchment co-evolution

    Directory of Open Access Journals (Sweden)

    P. A. Troch

    2013-03-01

    Full Text Available Catchment hydrologic partitioning, regional vegetation composition and soil properties are strongly affected by climate, but the effects of climate-vegetation-soil interactions on river basin water balance are still poorly understood. Here we use a physically-based hydrologic model separately parameterized in 12 US catchments across a climate gradient to decouple the impact of climate and landscape properties to gain insight into the role of climate-vegetation-soil interactions in long-term hydrologic partitioning. The 12 catchment models (with different parameterizations are subjected to the 12 different climate forcings, resulting in 144 10-yr model simulations. The results are analyzed per catchment (one catchment model subjected to 12 climates and per climate (one climate filtered by 12 different model parameterization, and compared to water balance predictions based on Budyko's hypothesis (E/P = φ (EP/P; E: evaporation, P: precipitation, EP: potential evaporation. We find significant anti-correlation between average deviations of the evaporation index (E/P computed per catchment vs. per climate, compared to that predicted by Budyko. Catchments that on average produce more E/P have developed in climates that on average produce less E/P, when compared to Budyko's prediction. Water and energy seasonality could not explain these observations, confirming previous results reported by Potter et al. (2005. Next, we analyze which model (i.e., landscape filter characteristics explain the catchment's tendency to produce more or less E/P. We find that the time scale that controls perched aquifer storage release explains the observed trend. This time scale combines several geomorphologic and hydraulic soil properties. Catchments with relatively longer aquifer storage release time scales produce significantly more E/P. Vegetation in these catchments have longer access to this additional groundwater source and thus are less prone to water stress. Further

  14. Legacy Contaminantion in UK catchments since the mid-19th century

    Science.gov (United States)

    Howden, N. J. K.; Burt, T. P.; Worrall, F.; Noacco, V.; Wagener, T.

    2014-12-01

    We present data from UK catchments to characterise impacts of industrial and agricultural development of UK river catchments since the mid-19th century. We draw heavily on the world's longest continuous water quality monitoring programme in the Thames River Basin (1868-date) and discuss the implications of both agricultural development, social and industrial change, and the impact of legislation on coupled land and water resource systems. Our review draws on both data and model analysis over a 145-year period and explores how a multitude of inter-linked drivers affects process-function and practical water resource management decision-support. Our work uncovers key drivers, catchment responses and emergent challenges for process science and regulation, with particular emphasis on the technical challenge for catchment scientists to provide both insight and workable solutions to maintain food and water security in intensively management river basins. We discuss issues of appropriate methods for both data capture and subsequent analyses to support short- and long-term decision making, and particularly considers the importance of advanced techniques to clarify uncertainties in extrapolation of short-term observations to inform long-term goals. We speculate as to future trajectories of catchment responses to current pressures, and potential pitfalls to immediate concerns that may often be at odds with overall requirements for continued use of natural resources in the future.

  15. AN APPROACH TO THE MODEL USE FOR MEASURING SUSPENDED SEDIMENT YIELD IN UNGAUGED CATCHMENTS

    Directory of Open Access Journals (Sweden)

    Sokchhay Heng

    2013-01-01

    Full Text Available Different types of water resources studies require the information of Suspended Sediment Yield (SSY in different time resolutions. In ungauged watersheds where hydrometeorogical time series are not available, the mean annual SSY (SSYa is solely predictable and catchment area is traditionally used as the predictor because it is the most important variable and generally determined during project planning. Firstly, this research tried to advance the traditional SSYa model by additionally associating global topographic data. Based on the jack-knife procedure, the modified method considering catchment area with slope greater than 15% was evaluated in 17 gauged catchments in the Lower Mekong Basin and the overall predictive accuracy was improved about 66% in term of mean absolute percentage error. Secondly, the predicted SSYa in each modeled catchment was monthly distributed using Unit mean annual Sedimentograph (USGa. The double-average USGa superior to the single-average one provides overall better quality results than the regionalized USGa dependent upon the spatial proximity approach. The model performance measured by Nash-Sutcliffe Efficiency (NSE is about 0.66 in median value and satisfactory results (NSE >0.50 are obtained in 11 catchments. Lastly, the validated regional model was regarded as a potential and feasible tool in solving sediment-ungauged issues in the basin.

  16. Water balance modeling of Upper Blue Nile catchments using a top-down approach

    Directory of Open Access Journals (Sweden)

    S. Tekleab

    2010-09-01

    Full Text Available The hydrological behavior and functioning of twenty catchments in the Upper Blue Nile basin have been analyzed using a top-down modeling approach that is based on Budyko's hypotheses. The objective is to obtain better understanding of catchment response for prediction in ungauged catchments. The water balance analysis using Budyko-type curve at annual scale reveals that the aridity index does not exert a first order control in most of the catchments. This implies the need to increase model complexity to a monthly time scale to include the effects of seasonal soil moisture dynamics. The dynamic water balance model used in this study predicts the direct runoff and other processes based on limit concept. The uncertainty of model parameters has been assessed using the GLUE (Generalized Likelihood Uncertainty Estimation. The results show that the majority of the parameters are reasonably well identifiable. Moreover, a multi-objective model calibration strategy has been employed within the GLUE framework to emphasize the different aspects of the hydrographs on low and high flows. The model has been calibrated and validated against observed streamflow time series and it shows good performance for the twenty catchments of the upper Blue Nile. During the calibration period (1995–2000 the Nash and Sutcliffe coefficient of efficiency for monthly flow prediction varied between 0.52 to 0.93 during high flows, while it varied between 0.32 to 0.90 during low flows (logarithms of flow series. The model is parsimonious and it is suggested that the resulting parameters can be used to predict monthly stream flows in the ungauged catchments of the Upper Blue Nile basin, which accounts about 60% of total Nile basin flow.

  17. Effect of catchment characteristics on the relationship between past discharge and the power law recession coefficient

    Science.gov (United States)

    Patnaik, Swagat; Biswal, Basudev; Nagesh Kumar, D.; Sivakumar, Bellie

    2015-09-01

    This study concerns the relationship between the power law recession coefficient k (in -dQ/dt = kQα, Q being discharge at the basin outlet) and past average discharge QN (where N is the temporal distance from the center of the selected time span in the past to the recession peak), which serves as a proxy for past storage state of the basin. The strength of the k-QN relationship is characterized by the coefficient of determination R2N, which is expected to indicate the basin's ability to hold water for N days. The main objective of this study is to examine how R2N value of a basin is related with its physical characteristics. For this purpose, we use streamflow data from 358 basins in the United States and selected 18 physical parameters for each basin. First, we transform the physical parameters into mutually independent principal components. Then we employ multiple linear regression method to construct a model of R2N in terms of the principal components. Furthermore, we employ step-wise multiple linear regression method to identify the dominant catchment characteristics that influence R2N and their directions of influence. Our results indicate that R2N is appreciably related to catchment characteristics. Particularly, it is noteworthy that the coefficient of determination of the relationship between R2N and the catchment characteristics is 0.643 for N = 45. We found that topographical characteristics of a basin are the most dominant factors in controlling the value of R2N. Our results may be suggesting that it is possible to tell about the water holding capacity of a basin by just knowing about a few of its physical characteristics.

  18. Modelling riverflow in the Volta Basin of West Africa : a data-driven framework

    OpenAIRE

    Amisigo, B. A.

    2006-01-01

    In this thesis, a riverflow modelling framework developed for monthly riverflow prediction in the 400,000 km2 Volta Basin of West Africa is presented. By analysing available catchment rainfall, runoff and potential evapotranspiration series in the basin using methods such as correlation plots, autoregressive (AR) and autoregressive with exogenous input (ARX) modelling, it is shown that the monthly catchment rainfall-runoff process is better characterised by non-linear models. First, a spatio-...

  19. Climate-vegetation-soil interactions and long-term hydrologic partitioning: signatures of catchment co-evolution

    Directory of Open Access Journals (Sweden)

    P. A. Troch

    2013-06-01

    subsurface storage release time scales produce significantly more E/P. Vegetation in these catchments have longer access to this additional groundwater source and thus are less prone to water stress. Further analysis reveals that climates that give rise to more (less E/P are associated with catchments that have vegetation with less (more efficient water use parameters. In particular, the climates with tendency to produce more E/P have catchments that have lower % root fraction and less light use efficiency. Our results suggest that their exists strong interactions between climate, vegetation and soil properties that lead to specific hydrologic partitioning at the catchment scale. This co-evolution of catchment vegetation and soils with climate needs to be further explored to improve our capabilities to predict hydrologic partitioning in ungauged basins.

  20. Flowpaths, source water contributions and water residence times in a Mexican tropical dry forest catchment

    Science.gov (United States)

    Farrick, Kegan K.; Branfireun, Brian A.

    2015-10-01

    Runoff in forested tropical catchments has been frequently described in the literature as dominated by the rapid translation of rainfall to runoff through surface and shallow subsurface pathways. However, studies examining runoff generation in tropical catchments with highly permeable soils have received little attention, particularly in tropical dry forests. We present a study focused on identifying the dominant flowpaths, water sources and stream water residence times in a tropical dry forest catchment near the Pacific coast of central Mexico. During the wet season, pre-event water contributions to stormflow ranged from 72% to 97%, with the concentrations of calcium, magnesium, sodium and potassium closely coupling the geochemistry of baseflow and groundwater from the narrow riparian/near-stream zone. Baseflow from the intermittent stream showed a strongly damped isotopic signature and a mean baseflow residence time of 52-110 days was estimated. These findings all suggest that instead of the surface and near-surface subsurface lateral pathways observed over many tropical catchments, runoff is generated through vertical flow processes and the displacement and discharge of stored water from the saturated zone. As the wet season progressed, contributions from the saturated zone persisted; however, the stormflow and baseflow geochemistry suggests that the contributing area of the catchment increased. Our results show that during the early part of the wet season, runoff originated primarily from the headwater portion of the catchment. As the wet season progressed and catchment wetness increased, connectivity among sub-basin was improved, resulting in runoff contributions from across the entire catchment.

  1. THE FORMATION OF THE OUTFLOW IN THE URBANISED CATCHMENT AREA ON THE EXAMPLE OF THE CATCHMENT OF STRZYŻA

    Directory of Open Access Journals (Sweden)

    Magda Sikora

    2015-01-01

    Full Text Available The aim of the study is to determine what influence made various forms of land use of catchment area on the size and variability of the outflow. Linking the flow rate with the forms of land use will determine which factors affect the runoff in the basin. The object of the research is Strzyża river basin situated within the administrative boundaries of the city of Gdańsk. It was found that streams flowing through urban areas, including the city of Gdańsk (river Strzyża, quickly react to any excess water. Heavy rain combined with the discharge of water through the storm sewer system results of increasing the flow and runoff in streams, among others, Strzyża river.

  2. Creating a catchment scale perspective for river restoration

    Directory of Open Access Journals (Sweden)

    L. Benda

    2011-09-01

    Full Text Available One of the major challenges in river restoration is to identify the natural fluvial landscape in catchments with a long history of river control. Intensive land use on valley floors often predates the earliest remote sensing: levees, dikes, dams, and other structures alter valley-floor morphology, river channels and flow regimes. Consequently, morphological patterns indicative of the fluvial landscape including multiple channels, extensive floodplains, wetlands, and fluvial-riparian and tributary-confluence dynamics can be obscured, and information to develop appropriate and cost effective river restoration strategies can be unavailable. This is the case in the Pas River catchment in northern Spain (650 km2, in which land use and development have obscured the natural fluvial landscape in many parts of the basin. To address this issue we used computer tools to examine the spatial patterns of fluvial landscapes that are associated with five domains of hydro-geomorphic processes and landforms. Using a 5-m digital elevation model, valley-floor surfaces were mapped according to elevation above the channel and proximity to key geomorphic processes. The predicted fluvial landscape is patchily distributed according to hillslope and valley topography, river network structure, and channel elevation profiles. The vast majority of the fluvial landscape in the main segments of the Pas River catchment is presently masked by human infrastructure, with only 15% not impacted by river control structures and development. The reconstructed fluvial landscape provides a catchment scale context to support restoration planning, in which areas of potential ecological productivity and diversity could be targeted for in-channel, floodplain and riparian restoration projects.

  3. Physical variables, nutrient status and primary productivity of Kyoga Basin lakes of Lemwa, Omunuo, Gawa, Adois and Owapet

    OpenAIRE

    Ochieng, H.; Ochaya, H.; Anguzu, A.; Magezi, G.

    2007-01-01

    The review report on Kyoga basin lakes (NAFIRRI 2007) described Kyoga basin lakes as important natural resource for the communities within the basin and the surrounding areas. Fisheries of the basin provide a source of protein, income, and employment to generally poor communities in the area. The lakes also generate revenue to the local Governments within the catchment. This indicates that the fisheries of Kyoga basin lakes are a key instrument in poverty eradication and food security. The la...

  4. Important progress on the use of isotope techniques and methods in catchment hydrology

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The use of isotope techniques and methods in catchment hydrology in the last 50 years has generated two major types of progress: (1) Assessment of the temporal variations of the major stocks and flows of water in catchments, from which the estimation of wa-ter residence times is introduced in this paper. (2) Assessment of catchment hydrologic processes, in which the interactions be-tween different waters, hydrographical separation, and bio-geochemical process are described by using isotopes tracers. Future progress on isotope techniques and methods in hydrology is toward the understanding of the hydrological process in large river basins. Much potential also waits realization in terms of how isotope information may be used to calibrate and test distributed rainfall-runoff models and regarding aid in the quantification of sustainable water resources management.

  5. Recasting catchment water balance for water allocation between human and environmental purposes

    Directory of Open Access Journals (Sweden)

    S. Zhou

    2015-01-01

    Full Text Available Rebalancing water allocation between human consumptive uses and the environment in water catchments is a global challenge. The conventional water balance approach which partitions precipitation into evapotranspiration (ET and surface runoff supports the optimization of water allocations among different human water use sectors under the cap of water supply. However, this approach is unable to support the emerging water management priority issue of allocating water between societal and ecological systems. This paper recast the catchment water balance by partitioning catchment total ET into ET for the society and ET for the natural ecological systems, and estimated the impacts of water allocation on the two systems in terms of gross primary productivity (GPP, in the Murray–Darling Basin (MDB of Australia over the period 1900–2010. With the recast water balance, the more than 100 year water management in the MDB was divided into four periods corresponding to major changes in basin management: period 1 (1900–1956 expansion of water and land use by the societal system, period 2 (1956–1985 maximization of water and land use by the societal system, period 3 (1985–2002 maximization of water diversion for the societal system, and period 4 (2002–present rebalancing of water and land use between the societal and ecological systems. The recast water balance provided new understandings of the water and land dynamics between societal and ecological systems in the MDB, and it highlighted the experiences and lessons of catchment water management in the MDB over the last more than 100 years. The recast water balance could serve as the theoretical foundation for water allocation to keep a dynamic balance between the societal and ecological systems within a basin for sustainable catchment development. It provides a new approach to advance the discipline of socio-hydrology.

  6. Nutrient sources in a Mediterranean catchment and their improvement for water quality management

    Science.gov (United States)

    Candela, Angela; Viviani, Gaspare

    2010-05-01

    Changes in land-use or management strategies may affect water outflow, sediment and nutrients loads. Thus, there is an increasing demand for quantitative information at the catchment scale that would help decision makers or planners to take appropriate decisions. The characterisation of water status, the description of pollution sources impact, the establishment of monitoring programs and the implementation of river basin management plans require an analysis of the current basin status and estimates of the relative significance of the different sources of pollution. Particularly, in this study the Soil and Water Assessment Tool (SWAT2000) model was considered since it is an integrated hydrological model that simulates both the qualitative as well as quantitative terms of hydrological balances. It is a spatially distributed hydrological model that operates on a daily time step at catchment scale developed by the Agricultural Research Service at the U.S. Department of Agriculture. Its purpose is to simulate water sediment and chemical yields on large river basins and possible impacts of land use, climate changes and watershed management. Integrated hydrological models are, nowadays, needed to support the implementation of integrated water management plans and to comply with the current requirements of the European Water Directive. Actually, they can help in evaluating current water resources, identify pollution sources, evaluate alternative management policies. More specifically, the analysis has been applied to the Oreto catchment (77 Km2), an agricultural and urbanised catchment located in Sicily (Italy). Residential, commercial, farm and industrial settlements cover almost the entire area. The climate is Mediterranean with hot dry summer and rainy winter season. The hydrological response of this basin is dominated by long dry seasons and following wetting-up periods, during which even large inputs of rainfall may produce little or no response at the basin outlet

  7. Analysis of relation between water quality according to chemical indexes and water catchment area use

    Directory of Open Access Journals (Sweden)

    Ivicheva Ksenya Nikolayevna

    2013-10-01

    Full Text Available Catch basins for a number of the rivers of Vologda region were framed using ARCGIS 10, method Hydrobiology , and their usage was assessed. Parts of catchments for 11 small and medium rivers with different anthropogenic stress were analyzed. The area of each catch basin was divided into 3 categories: little-developed, agricultural and urban ones. For 3 city rivers 2 categories were analized. The data on catchment area use were recorded for all sites from satellite image with ScanEx Image Processor. Areas of 3 land-use types (forest, agriculture, and urbanized terrain were calculated. Forest on the parts of catchments composed from 12 to 100%, urbanized terrain composing from 0 to 51,5 %. Areas of differnt categories were compared with hydrochemical indexes of water quality. Indexes of water quality showed strong positive correlation with the areas of urbanized terrains on the parts of catchments (0,81-0,95,but weak correlation with areas of agriculture (0,62-0,8. As for the forest areas, they showed strong negative correlation (-0,75…-0,9. Indexes of water quality were sensitive to negative anthropology influence.

  8. A framework of integrated hydrological and hydrodynamic models using synthetic rainfall for flash flood hazard mapping of ungauged catchments in tropical zones

    OpenAIRE

    Lohpaisankrit, Worapong; Meon, Günter; Tingsanchali, Tawatchai

    2016-01-01

    Flash flood hazard maps provide a scientific support to mitigate flash flood risk. The present study develops a practical framework with the help of integrated hydrological and hydrodynamic modelling in order to estimate the potential flash floods. We selected a small pilot catchment which has already suffered from flash floods in the past. This catchment is located in the Nan River basin, northern Thailand. Reliable meteorological and hydrometric data are missing in the cat...

  9. Microbial water pollution: a screening tool for initial catchment-scale assessment and source apportionment.

    Science.gov (United States)

    Kay, D; Anthony, S; Crowther, J; Chambers, B J; Nicholson, F A; Chadwick, D; Stapleton, C M; Wyer, M D

    2010-11-01

    The European Union Water Framework Directive requires that Management Plans are developed for individual River Basin Districts. From the point of view of faecal indicator organisms (FIOs), there is a critical need for screening tools that can provide a rapid assessment of the likely FIO concentrations and fluxes within catchments under base- and high-flow conditions, and of the balance ('source apportionment') between agriculture- and sewage-derived sources. Accordingly, the present paper reports on: (1) the development of preliminary generic models, using water quality and land cover data from previous UK catchment studies for assessing FIO concentrations, fluxes and source apportionment within catchments during the summer bathing season; (2) the calibration of national land use data, against data previously used in the models; and (3) provisional FIO concentration and source-apportionment assessments for England and Wales. The models clearly highlighted the crucial importance of high-flow conditions for the flux of FIOs within catchments. At high flow, improved grassland (and associated livestock) was the key FIO source; FIO loadings derived from catchments with high proportions of improved grassland were shown to be as high as from urbanized catchments; and in many rural catchments, especially in NW and SW England and Wales, which are important areas of lowland livestock (especially dairy) farming, ≥ 40% of FIOs was assessed to be derived from agricultural sources. In contrast, under base-flow conditions, when there was little or no runoff from agricultural land, urban (i.e. sewerage-related) sources were assessed to dominate, and even in rural areas the majority of FIOs were attributed to urban sources. The results of the study demonstrate the potential of this type of approach, particularly in light of climate change and the likelihood of more high-flow events, in underpinning informed policy development and prioritization of investment. PMID:19717181

  10. How microtopography and soil morphology can help decipher flow paths and processes in headwater catchments

    Science.gov (United States)

    Gannon, J. P.; McGuire, K. J.; Bailey, S.

    2012-12-01

    Headwater catchments dominate the drainage basins of larger rivers and determine the water quality of downstream water bodies. In these catchments, hydrology strongly influences soil development and soil chemistry, thereby determining stream water quality. This study aims to explain spatial and temporal variations of flow paths and fine scale variations in hydrologic regimes at the headwater catchment scale utilizing a hydropedological approach. Hydropedologic units (HPUs), defined by differing soil morphological characteristics provide a framework for describing the function of different soil types in a catchment. Preliminary analysis and field observations also indicate that HPU locations will be predictable based on surface microtopography calculated from a 1-meter, LiDAR (Light Detection and Range) derived digital elevation model. We show that water table data from 50 wells distributed throughout the catchment confirms HPUs are indicative of specific hydrologic flow regimes, including threshold behavior, consistent with predictions based on soil morphology alone. This study focuses on three intensive study sites representative of typical soil morphological development in a small catchment. Furthering the water table analysis, measures of saturated and unsaturated hydrologic regimes, surface topographic characteristics, subsurface characteristics, and soil morphology were compared for the three intensive sites in an effort to quantify the effect of surface microtopography on the proposed hydropedologic system. Preliminary analysis shows matric potential gradients develop laterally down slope at site locations hypothesized to be indicative of lateral podsolization based on site topography and soil morphology. These results are in agreement with our findings describing threshold behavior in water table development at the same sites. The results of this study suggest a hydropedological approach may be a useful tool for describing catchment runoff response as well

  11. Geomorphological characterization of endorheic basins in northern Chile

    Science.gov (United States)

    Dorsaz, J.; Gironas, J. A.; Escauriaza, C. R.; Rinaldo, A.

    2011-12-01

    Quantitative geomorphology regroups a large number of interesting tools to characterize natural basins across scales. The application of these tools to several river basins allows the description and comparison of geomorphological properties at different spatial scales as oppose to more traditional descriptors that are typically applied at a single scale, meaning the catchment scale. Most of the recent research using these quantitative geomorphological tools has focused on open catchments and no specific attention has been given to endorheic basins, and the possibility of having particular features that distinguish them from exorheic catchments. The main objective of our study is to characterize endorheic basins and investigate whether these special geomorphological features can be identified. Because scaling invariance is a widely observed and relatively well quantified property of open basins, it provides a suitable tool to characterize differences between the geomorphology of closed and open basins. Our investigation focuses on three closed basins located in northern Chile which describe well the diversity in the geomorphology and geology of this arid region. Results show that endhoreic basins exhibit different slope-area and flow paths sinuosity regimes compared to those observed in open basins. These differences are in agreement with the particular self-similar behavior across spatial scales of the Euclidean length of subcatchments, as well as the Hack's law and Horton's ratios. These regimes imply different physical processes inside the channel network regardless of the basin area, and they seem to be related to the endorheic character of these basins. The analysis of the probability density functions of contributing areas and lengths to the lower region shows that the hypothesis of self-similarity can also be applied to closed basins. Theoretical expressions for these distributions were derived and validated by the data. Future research will focus on (1

  12. Isotope techniques in catchment behaviour studies with particular emphasis on snowmelt runoff investigations

    International Nuclear Information System (INIS)

    The dynamics of runoff occurring mainly by snowmelt have been investigated by the aid of environmental isotopes. Regular samples collected from river water and snow cover throughout 1978 to 1981 at two selected catchment basins in eastern Turkey were analysed for their oxygen-18, deuterium and tritium contents. The tritium results together with detailed hydrological and hydro-meteorological data have enabled to study the time distribution of various component flow systems involved in the total runoff resulting from snowmelt

  13. The frequency of precipitation days in the Yangtze Catchment from 1950 to 2000

    International Nuclear Information System (INIS)

    This paper explores the frequency of precipitation days by using different percentiles in the Yangtze River catchment from 1950 to 2000. Some interesting facts have been revealed through the present study. The positive (increasing) trends of the yearly precipitation days at the 75 th percentile appears in most of the Yangtze River catchment, especially in the northern regions of the upper and the middle reaches of the catchment. The Sichuan basin is the only region with negative trends. The transitional area from negative to positive trends is found east of the Sichuan basin in the Three Gorges area. For the 95 th percentile, the negative trend regions are still mainly in Sichuan basin but extend to northern regions and there are also obviously increasing trend centers in the middle and lower reaches of Yangtze river catchment. On the decadal time scale, the most significant positive trends at the 75th percentiles are in the middle reaches in 1980s and 1990s. The lower reaches show significant positive trends in 1980s. Those positive phases greatly contribute to the positive trends of the whole catchment during the last two decades. The most significant negative phase also occurs in the middle reaches during the earlier three decades. For this case, it seems that the precipitation days in the middle reaches are more sensitive to changes than other regions in the Yangtze River catchment. Take the Yangtze River catchment as a whole, a positive trend is very obvious for this percentile. For the 95 th percentile, the trends between the middle and lower reaches of the Yangtze River catchment are coherent: after two decades (1960s and 1970s) of negative phases, the most significant increasing trend is shown in the last two decades. On the other side, the fluctuation of the precipitation days in the catchment of the upper reaches over the 50 years is somewhat smoother than for other regions. For the whole catchment, the precipitation days in the 1950s and in the 1990s are

  14. Winter streamflow analysis in frozen, alpine catchments to quantify groundwater contribution and properties

    Science.gov (United States)

    Stoelzle, Michael; Weiler, Markus

    2016-04-01

    contributions is helpful to assess the water sustainability of alpine catchments functioning as water towers for downstream water basins. We outline how well-known hydrograph and recession analyses in alpine catchments can help to explore the role of catchment storage and to advance our understanding of (ground-)water management in alpine environments.

  15. Removal of Heavy Metals and PAH in Retention Basins

    DEFF Research Database (Denmark)

    Larsen, Torben; Neerup-Jensen, Ole

    2004-01-01

    Solid seperation in retention basins is strongly non-linear and depends significantly on the flow rate and the settling characteristics of the particles. Accordingly the calculation of the annual loads of pollutants from storm overflows including basins is rather complex and time consuming. The...... paper describes how laboratory investigations and CFD-modelling of flow dependant particle separation in retention basins are combined with long-simulation of storm water overflows including basins based on historical time series of rainfalls also taking into account the flow dependant solid seperation...... in order to calculate annual loads of pollutants from urban catchments. The study cover Cd, Cu, Ni, Pb, Zn and PAH....

  16. Influence of basin connectivity on sediment source, transport, and storage within the Mkabela Basin, South Africa

    Directory of Open Access Journals (Sweden)

    J. R. Miller

    2013-02-01

    Full Text Available The management of sediment and other non-point source (NPS pollution has proven difficult, and requires a sound understanding of particle movement through the drainage system. The primary objective of this investigation was to obtain an understanding of NPS sediment source(s, transport, and storage within the Mkabela Basin, a representative agricultural catchment within the KwaZulu–Natal Midlands of eastern South Africa, by combining geomorphic, hydrologic and geochemical fingerprinting analyses.

    The Mkabela Basin can be subdivided into three distinct subcatchments that differ in their ability to transport and store sediment along the axial valley. Headwater (upper catchment areas are characterized by extensive wetlands that act as significant sediment sinks. Mid-catchment areas, characterized by higher relief and valley gradients, exhibit few wetlands, but rather are dominated by a combination of alluvial and bedrock channels that are conducive to sediment transport. The lower catchment exhibits a low-gradient alluvial channel that is boarded by extensive riparian wetlands that accumulate large quantities of sediment (and NPS pollutants.

    Fingerprinting studies suggest that silt- and clay-rich layers found within wetland and reservoir deposits of the upper and upper-mid subcatchments are derived from the erosion of fine-grained, valley bottom soils frequently utilized as vegetable fields. Coarser-grained deposits within these wetlands and reservoirs result from the erosion of sandier hillslope soils extensively utilized for sugar cane, during relatively high magnitude runoff events that are capable of transporting sand-sized sediment off the slopes. Thus, the source of sediment to the axial valley varies as a function of sediment size and runoff magnitude. Sediment export from upper to lower catchment areas was limited until the early 1990s, in part because the upper catchment wetlands were hydrologically disconnected from

  17. Multiscale investigations in a mesoscale catchment – hydrological modelling in the Gera catchment

    Directory of Open Access Journals (Sweden)

    P. Krause

    2006-01-01

    Full Text Available The application of the hydrological process-oriented model J2000 (J2K is part of a cooperation project between the Thuringian Environmental Agency (Thüringer Landesanstalt für Umwelt und Geologie – TLUG and the Department of Geoinformatics of the Friedrich-Schiller-University Jena focussing on the implementation of the EU water framework directive (WFD. In the first project phase J2K was parametrised and calibrated for a mesoscale catchment to quantify if it can be used as hydrological part of a multi-objective tool-box needed for the implementation of the WFD. The main objectives for that pilot study were: The development and application of a suitable distribution concept which provide the spatial data basis for various tasks and which reflects the specific physiogeographical variability and heterogeneity of river basins adequately. This distribution concept should consider the following constraints: The absolute number of spatial entities, which forms the basis for any distributive modelling should be as small as possible, but the spatial distributed factors, which controls quantitative and qualitative hydrological processes should not be generalised to much. The distribution concept of hydrological response units HRUs (Flügel, 1995 was selected and enhanced by a topological routing scheme (Staudenrausch, 2001 for the simulation of lateral flow processes. J2K should be calibrated for one subbasin of the pilot watershed only. Then the parameter set should be used on the other subbasins (referred as transfer basins to investigate and quantify the transferability of a calibrated model and potential spatial dependencies of its parameter set. In addition, potential structural problems in the process description should be identified by the transfer to basins which show a different process dominance as the one which was used for calibration does. Model calibration and selection of efficiency criteria for the quantification of the model quality

  18. Hydropedological insights when considering catchment classification

    Directory of Open Access Journals (Sweden)

    J. Bouma

    2011-06-01

    Full Text Available Soil classification systems are analysed to explore the potential of developing classification systems for catchments. Soil classifications are useful to create systematic order in the overwhelming quantity of different soils in the world and to extrapolate data available for a given soil type to soils elsewhere with identical classifications. This principle also applies to catchments. However, to be useful, soil classifications have to be based on permanent characteristics as formed by the soil forming factors over often very long periods of time. When defining permanent catchment characteristics, discharge data would therefore appear to be less suitable. But permanent soil characteristics do not necessarily match with characteristics and parameters needed for functional soil characterization focusing, for example, on catchment hydrology. Hydropedology has made contributions towards the required functional characterization of soils as is illustrated for three recent hydrological catchment studies. However, much still needs to be learned about the physical behaviour of anisotropic, heterogeneous soils with varying soil structures during the year and about spatial and temporal variability. The suggestion is made therefore to first focus on improving simulation of catchment hydrology, possibly incorporating hydropedological expertise, before embarking on a catchment classification effort which involves major input of time and involves the risk of distraction. In doing so, we suggest to also define other characteristics for catchment performance than the traditionally measured discharge rates. Such characteristics may well be derived from societal issues being studied, as is illustrated for the Green Water Credits program.

  19. Modelling riverflow in the Volta Basin of West Africa : a data-driven framework

    NARCIS (Netherlands)

    Amisigo, B.A.

    2006-01-01

    In this thesis, a riverflow modelling framework developed for monthly riverflow prediction in the 400,000 km2 Volta Basin of West Africa is presented. By analysing available catchment rainfall, runoff and potential evapotranspiration series in the basin using methods such as correlation plots, autor

  20. Attributes for NHDplus Catchments (Version 1.1) for the Conterminous United States: Population Density, 2000

    Science.gov (United States)

    Wieczorek, Michael E.; LaMottem, Andrew E.

    2010-01-01

    This data set represents the average population density, in number of people per square kilometer multiplied by 10 for the year 2000, compiled for every catchment of NHDPlus for the conterminous United States. The source data set is the 2000 Population Density by Block Group for the Conterminous United States (Hitt, 2003). The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy River basins, contains NHDPlus Production Units 4, 5

  1. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: Physiographic Provinces

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This dataset represents the area of each physiographic province (Fenneman and Johnson, 1946) in square meters, compiled for every catchment of NHDPlus for the conterminous United States. The source data are from Fenneman and Johnson's Physiographic Provinces of the United States, which is based on 8 major divisions, 25 provinces, and 86 sections representing distinctive areas having common topography, rock type and structure, and geologic and geomorphic history (Fenneman and Johnson, 1946). The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins

  2. Attributes for NHDPlus catchments (version 1.1) for the conterminous United States: surficial geology

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the area of surficial geology types in square meters compiled for every catchment of NHDPlus for the conterminous United States. The source data set is the "Digital data set describing surficial geology in the conterminous US" (Clawges and Price, 1999). The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy River basins, contains NHDPlus Production Units 4, 5, 7 and 9. MRB4, covering the Missouri River

  3. Attributes for NHDPlus catchments (Version 1.1) for the conterminous United States: STATSGO soil characteristics

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents estimated soil variables compiled for every catchment of NHDPlus for the conterminous United States. The variables included are cation exchange capacity, percent calcium carbonate, slope, water-table depth, soil thickness, hydrologic soil group, soil erodibility (k-factor), permeability, average water capacity, bulk density, percent organic material, percent clay, percent sand, and percent silt. The source data set is the State Soil ( STATSGO ) Geographic Database (Wolock, 1997). The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee

  4. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: Hydrologic Landscape Regions

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the area of Hydrologic Landscape Regions (HLR) compiled for every catchment of NHDPlus for the conterminous United States. The source data set is a 100-meter version of Hydrologic Landscape Regions of the United States (Wolock, 2003). HLR groups watersheds on the basis of similarities in land-surface form, geologic texture, and climate characteristics. The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris

  5. Attributes for NHDPlus Catchments (Version 1.1): Level 3 Nutrient Ecoregions, 2002

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the area of each level 3 nutrient ecoregion in square meters, compiled for every catchment of NHDPlus for the conterminous United States. The source data are from the 2002 version of the U.S. Environmental Protection Agency's (USEPA) Aggregations of Level III Ecoregions for National Nutrient Assessment & Management Strategy (USEPA, 2002). The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy River basins

  6. Attributes for NHDPlus Catchments (Version 1.1) in the Conterminous United States: Bedrock Geology

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the area of bedrock geology types in square meters compiled for every catchment of NHDPlus for the conterminous United States. The source data set is the "Geology of the Conterminous United States at 1:2,500,000 Scale--A Digital Representation of the 1974 P.B. King and H.M. Beikman Map" (Schuben and others, 1994). The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy River basins, contains NHDPlus

  7. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: Level 3 Ecoregions

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the estimated area of level 3 ecological landscape regions (ecoregions), as defined by Omernik (1987), compiled for every catchment of NHDPlus for the conterminous United States. The source data set is Level III Ecoregions of the Continental United States (U.S. Environmental Protection Agency, 2003). The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy River basins, contains NHDPlus Production Units 4

  8. Influence of basin connectivity on sediment source, transport, and storage within the Mkabela Basin, South Africa

    Directory of Open Access Journals (Sweden)

    J. R. Miller

    2012-09-01

    Full Text Available The management of sediment and other non-point source (NPS pollution has proven difficult, and requires a sound understanding of particle movement through the drainage system. The primary objective of this investigation was to obtain an understanding of NPS sediment source(s, transport, and storage within the Mkabela basin, a representative agricultural catchment within the KwaZulu-Natal Midlands of southeastern South Africa, by combining geomorphic, hydrologic and geochemical fingerprinting analyses.

    The Mkabela Basin can be subdivided into three distinct subcatchments that differ in their ability to transport and store sediment along the axial valley. Headwater (upper catchment areas are characterized by extensive wetlands that act as significant sediment sinks. Mid-catchment areas, characterized by higher relief and valley gradients, exhibit few wetlands, but rather are dominated by a combination of alluvial and bedrock channels that are conducive to sediment transport. The lower catchment exhibits a low-gradient alluvial channel that is boarded by extensive riparian wetlands that accumulate large quantities of sediment (and NPS pollutants.

    Fingerprinting studies suggest that silt- and clay-rich layers found within wetland and reservoir deposits are derived from the erosion of fine-grained, valley bottom soils frequently utilized as vegetable fields. Coarser-grained deposits within both wetlands and reservoirs result from the erosion of sandier hillslope soils extensively utilized for sugar cane, during relatively high magnitude runoff events that are capable of transporting sand-sized sediment off the slopes. Thus, the source of sediment to the axial valley varies as a function of sediment size and runoff magnitude. Sediment export from the basin was limited until the early 1990s, in part because the upper catchment wetlands were hydrologically disconnected from lower parts of the watershed during low- to moderate flood

  9. Application of Rainfall-runoff Models to Zard River Catchment's

    Directory of Open Access Journals (Sweden)

    M. B. Rahnama

    2005-01-01

    Full Text Available Rainfall-runoff models are nonlinear processes according to the sequential and spatial distribution of the rainfall. So, it is difficult to explain the response of catchments systems with the simple models. In the present work simulation of the rainfall-runoff processes have been carried out by the Artificial Neural Networks (ANN and the HEC-HMS models. The ANN models of Multi Layer Perceptron (MLP with two hidden layers and Radial Basis Function (RBF, were used to simulate this process. It has been applied to the Zard river basin in Khuzestan province using daily rainfall and runoff data, during the period of 1991 to 2000. During this period, 14 flood events were selected to simulate rainfall-runoff processes by the HEC-HMS model. Results of two models were compared with the observed data of Zard river basin. It is shown that RBF model is much better than, MLP and HEC-HMS models for simulating of the rainfall-runoff process in Zard river basin.

  10. Collaborative knowledge in catchment research networks

    Science.gov (United States)

    Macleod, Christopher Kit

    2015-04-01

    There is a need to improve the production, sharing and use of collaborative knowledge of catchment systems through networks of researchers, policy makers and practitioners. This requires greater levels of systems based integrative research. In parallel to the growing realization that greater levels of collaborative knowledge in scientific research networks are required, a digital revolution has been taking place. This has been driven primarily by the emergence of distributed networks of computers and standards-based interoperability. The objective of this paper is to present the status and research needs for greater levels of systems based integrative research for the production, sharing and use of collaborative knowledge in catchment research networks. To enable increased levels of integrative research depends on development and application of digital technologies to improve collection, use and sharing of data and devise new knowledge infrastructures. This paper focuses on the requirements for catchment observatories that integrate existing and novel physical, social and digital networks of knowledge infrastructures. To support this focus, I present three leading international examples of collaborative networks of catchment researchers and their development of catchment observatories. In particular, the digital infrastructures they have developed to support collaborative knowledge in catchment research networks. These examples are from North America (NSF funded CUAHSI HIS) and from Europe (UK NERC funded EVOp and the German Helmholtz Association Centers funded TERENO/TEODOOR). These exemplars all supported advancing collaborative knowledge in catchment research networks through the development of catchment observatories. I will conclude by discussing the future research directions required for greater levels of production, sharing and use of collaborative knowledge in catchment research networks based on catchment systems science.

  11. RUNOFF POTENTIAL OF MUREŞ RIVER UPPER BASIN TRIBUTARIES

    OpenAIRE

    SOROCOVSCHI V.; HORVÁTH Cs

    2012-01-01

    Runoff Potential of Mureş River Upper Basin Tributaries. The upper basin of the Mureş River includes a significant area of the Eastern Carpathians central western part with different runoff formation conditions. In assessing the average annual runoff potential we used data from six gauging stations and made assessments on three distinct periods. Identifying the appropriate areas of the obtained correlations curves (between specific average runoff and catchments mean altitude) allowed the asse...

  12. Data-based information gain on the response behaviour of hydrological models at catchment scale

    Science.gov (United States)

    Willems, Patrick

    2013-04-01

    A data-based approach is presented to analyse the response behaviour of hydrological models at the catchment scale. The approach starts with a number of sequential time series processing steps, applied to available rainfall, ETo and river flow observation series. These include separation of the high frequency (e.g., hourly, daily) river flow series into subflows, split of the series in nearly independent quick and slow flow hydrograph periods, and the extraction of nearly independent peak and low flows. Quick-, inter- and slow-subflow recession behaviour, sub-responses to rainfall and soil water storage are derived from the time series data. This data-based information on the catchment response behaviour can be applied on the basis of: - Model-structure identification and case-specific construction of lumped conceptual models for gauged catchments; or diagnostic evaluation of existing model structures; - Intercomparison of runoff responses for gauged catchments in a river basin, in order to identify similarity or significant differences between stations or between time periods, and relate these differences to spatial differences or temporal changes in catchment characteristics; - (based on the evaluation of the temporal changes in previous point:) Detection of temporal changes/trends and identification of its causes: climate trends, or land use changes; - Identification of asymptotic properties of the rainfall-runoff behaviour towards extreme peak or low flow conditions (for a given catchment) or towards extreme catchment conditions (for regionalization, ungauged basin prediction purposes); hence evaluating the performance of the model in making extrapolations beyond the range of available stations' data; - (based on the evaluation in previous point:) Evaluation of the usefulness of the model for making extrapolations to more extreme climate conditions projected by for instance climate models. Examples are provided for river basins in Belgium, Ethiopia, Kenya

  13. Use of modeling to protect, plan, and manage water resources in catchment areas.

    Science.gov (United States)

    Constant, Thibaut; Charrière, Séverine; Lioeddine, Abdejalil; Emsellem, Yves

    2016-08-01

    The degradation of water resources by diffuse pollution, mainly due to nitrate and pesticides, is an important matter for public health. Restoration of the quality of natural water catchments by focusing on their catchment areas is therefore a national priority in France. To consider catchment areas as homogeneous and to expend an equal effort on the entire area inevitably leads to a waste of time and money, and restorative actions may not be as efficient as intended. The variability of the pedological and geological properties of the area is actually an opportunity to invest effort on smaller areas, simply because every action is not equally efficient on every kind of pedological or geological surface. Using this approach, it is possible to invest in a few selected zones that will be efficient in terms of environmental results. The contributive hydraulic areas (CHA) concept is different from that of the catchment area. Because the transport of most of the mobile and persistent pollutants is primarily driven by water circulation, the concept of the CHA is based on the water pathway from the surface of the soil in the catchment area to the well. The method uses a three-dimensional hydrogeological model of surface and groundwater integrated with a geographic information system called Watermodel. The model calculates the contribution (m(3)/h or %) of each point of the soil to the total flow pumped in a well. Application of this model, partially funded by the Seine Normandy Basin Agency, to the catchment of the Dormelles Well in the Cretaceous chalk aquifer in the Orvanne valley, France (catchment area of 23,000 ha at Dormelles, county 77), shows that 95 % of the water pumped at the Dormelles Well comes from only 26 % of the total surface area of the catchment. Consequently, an action plan to protect the water resource will be targeted at the 93 farmers operating in this source area rather than the total number of farmers (250) across the entire 23,000 ha. Another

  14. Parsimonious hydrological modeling of urban sewer and river catchments

    Science.gov (United States)

    Coutu, Sylvain; Del Giudice, Dario; Rossi, Luca; Barry, D. A.

    2012-09-01

    SummaryA parsimonious model of flow capable of simulating flow in natural/engineered catchments and at WWTP (Wastewater Treatment Plant) inlets was developed. The model considers three interacting, dynamic storages that account for transfer of water within the system. One storage describes the “flashy” response of impervious surfaces, another pervious areas and finally one storage describes subsurface flow. The sewerage pipe network is considered as an impervious surface and is thus included in the impervious surface storage. In addition, the model assumes that water discharged from several CSOs (combined sewer overflows) can be accounted for using a single, characteristic CSO. The model was calibrated on, and validated for, the Vidy Bay WWTP, which receives effluent from Lausanne, Switzerland (population about 200,000), as well as for an overlapping urban river basin. The results indicate that a relatively simple approach is suitable for predicting the responses of interacting engineered and natural hydrosystems.

  15. SOILS VULNERABILITY OF CATCHMENT ALMAŞ AT GEOMORPHOLOGIC CONTEMPORARY PROCESSES

    Directory of Open Access Journals (Sweden)

    MĂDĂLINA-IOANA RUS

    2015-03-01

    Full Text Available Soils vulnerability of the Catchment Almas geomorphologic processes. Almas Basin, signed lower lithologic Miocene soils deposits, shows six classes: Cernisols, Cambisols, Luvisols, Hydrosols, Pelisols, Protosols (after SRTS, 2003. The largest share is attributed to Luvisols class (60%, followed by undeveloped soil represented by Protosols and Antrisols (15%, followed by the remaining classes with lower weights: Cambisols (13%, Cernisols (7%, Pelisols (4%, Hydrosols (1%. Contemporary geomorphological processes (surface and deep erosion, mass movements change agricultural areas and forest ratio or flow out of economic network tens of hectares annually. Soil vulnerability to the manifestation of these processes is expressed by disturbing soil horizons, coastal springs appearance and growth of the adjoining excess moisture, soil sealing productive by dropping or by alienation.

  16. Ecohydrological evolution in the catchment of Lake Drūkšiai, Lithuania, under anthropogenic pressure

    OpenAIRE

    Mažeika, Jonas; Taminskas, Julius; Paškauskas, Ričardas; Bodoyan, Armen; Baghdassaryan, Hyke; Tozalakyan, Petros; Davtyan, Vahan; Grillot, Jean-Claude; Travi, Yves

    2006-01-01

    The catchment area of Lake Drūkšiai (the Ignalina Nuclear Power Plant cooling basin) is exposed to severe anthropogenic pressures due to urbanization, industrialization and, to a smaller scale, to agricultural development. Ecological changes in the lake are investigated in connection with the water balance of Lake Drūkšiai and the interaction of surface water and groundwater in the catchment. The main sources which contribute to the most active water exchange in the lake are total surface run...

  17. Doing hydrology backwards in tropical humid catchments

    Science.gov (United States)

    Real Rangel, R.; Brena-Naranjo, J. A.; Pedrozo-Acuña, A.

    2015-12-01

    Top-down approaches in hydrology offer the possibility to predict water fluxes at the catchment scale based on the interpretation of the observed hydrological response at the catchment itself. Doing hydrology backwards (inferring precipitation and evapotranspiration rates at the catchment scale from streamflow measurements, see Kirchner (2009)) can be a useful methodology for estimating water fluxes at the catchment and regional scales. Previous studies using this inverse modeling approach have been performed in regions (UK, Switzerland, France, Eastern US) where energy-limited (in winter and early spring) and water-limited conditions (in summer) prevail during a large period of the year. However, such approach has not been tested in regions characterized by a quasi-constant supply of water and energy (e.g. humid tropics). The objective of this work is to infer annual rates of precipitation and evapotranspiration over the last decade in 10 catchments located in Mexico's tropical humid regions. Hourly discharge measurements during recession periods were analyzed and parameters for the nonlinear storage-discharge relationship of each catchment were derived. Results showed large variability in both catchment-scale precipitation and evapotranspiration rates among the selected study sites. Finally, a comparison was done between such estimates and those obtained from remotely-sensed data (TRMM for precipitation and MOD16 for evapotranspiration).

  18. Water Catchment and Storage Monitoring

    Science.gov (United States)

    Bruenig, Michael; Dunbabin, Matt; Moore, Darren

    2010-05-01

    Sensors and Sensor Networks technologies provide the means for comprehensive understanding of natural processes in the environment by radically increasing the availability of empirical data about the natural world. This step change is achieved through a dramatic reduction in the cost of data acquisition and many orders of magnitude increase in the spatial and temporal granularity of measurements. Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO) is undertaking a strategic research program developing wireless sensor network technology for environmental monitoring. As part of this research initiative, we are engaging with government agencies to densely monitor water catchments and storages, thereby enhancing understanding of the environmental processes that affect water quality. In the Gold Coast hinterland in Queensland, Australia, we are building sensor networks to monitor restoration of rainforest within the catchment, and to monitor methane flux release and water quality in the water storages. This poster will present our ongoing work in this region of eastern Australia. The Springbrook plateau in the Gold Coast hinterland lies within a World Heritage listed area, has uniquely high rainfall, hosts a wide range of environmental gradients, and forms part of the catchment for Gold Coast's water storages. Parts of the plateau are being restored from agricultural grassland to native rainforest vegetation. Since April 2008, we have had a 10-node, multi-hop sensor network deployed there to monitor microclimate variables. This network will be expanded to 50-nodes in February 2010, and to around 200-nodes and 1000 sensors by mid-2011, spread over an area of approximately 0.8 square kilometers. The extremely dense microclimate sensing will enhance knowledge of the environmental factors that enhance or inhibit the regeneration of native rainforest. The final network will also include nodes with acoustic and image sensing capability for

  19. SWAT model application in a data scarce tropical complex catchment in Tanzania

    Science.gov (United States)

    Ndomba, Preksedis; Mtalo, Felix; Killingtveit, Aanund

    This study intended to validate the Soil and Water Assessment Tool (SWAT) model in data scarce environment in a complex tropical catchment in the Pangani River Basin located in northeast Tanzania. The validation process involved the model initialization, calibration, verification and sensitivity analysis. Both manual and auto-calibration procedures were used to facilitate the comparison of the results with past studies in the same catchment. For this study, some model parameters including Soil depth (SOL_Z) and Saturated hydraulic conductivity (SOL_K) were assumed uniform within the study catchment and were therefore lumped comprising the huge computation resource requirement of the SWAT model. Results indicated that the same set of important parameters was identified with or without the use of observed flows data. Some of the parameters had physical interpretation and could therefore relate directly to hydrological controlling factors within the catchment. Despite swapping ranking importance of parameters, these results suggest the suitability of the SWAT model for identifying hydrological controlling factors/parameters in ungauged catchments. Results of calibration and validation at the daily timescale gave moderately satisfactory Nash-Sutcliffe Coefficient of Efficiency (CE) of 54.6% for calibration and 68% for validation while simulated and observed mean annual flow discharges gave an Index of Volumetric Fit (IVF) of 100%. The study further indicated the improvement of model estimation when more reliable spatial representation of rainfall was used. Although in this study SWAT model has performed satisfactorily in data poor and complex catchment, the authors recommend a wider validation effort of the model before it is adopted for operational purpose.

  20. Effects of fires on flood frequency curve in mediterranean catchments

    Science.gov (United States)

    Candela, A.; Aronica, G.

    2003-04-01

    Fire is one of the major factors affecting Mediterranean catchments: the destruction of the forested ecosystem of a basin has important consequences for its hydrological behaviour. In fact, fire reduces protection of the surface resulting from the loss in vegetation cover and will to increase the water repellency or hydrophobicity of the soil surface. The problem of fires in Sicily strongly affect the hydrological behaviour and the soil conservation of natural areas: hot dry summers, rainfalls with short duration and high intensity, anthropic changes being deforestation and increasing of impervious areas. Aim of this paper is to analyse the effects of wildfire on the flood regime of a sicilian cathcment. In a previous studies of the same authors, changes in the hydrological regime due to the fires have been recognized in the same catchment at monthly and daily scale. In order to understand if these changes also affect the occurrence of extreme events (i.e. peak discharges), the flood frequency curves, before and after the fire, have been analysed and compared. The flood frequency curve for the pre-fire condition has been obtained by peak discharge data provided by the National Hydrographic Service, while, such data were not available for the post-fire condition. To overcome these limitations, a Montecarlo analysis has been carried out on the basis of strategy described as follows: (i) a distributed rainfall-runoff model, TOPMODEL, has been calibrated on hystorical events measured at catchment outlet in the pre-and post-fire conditions in order to recognise changes in the hydrological response of the catchment; (ii) a Neymann-Scott rainfall stochastic model has been used to generate 10000 rainfall time series with an hourly time step. (iii) the flood frequency curve after the wildfire has been derived apart from the output of TOPMODEL runs with the syntethic rainfall events as input. As expected, changes in flood regime, with an increase of peak discharge and a

  1. Modeling Ecohydrological Processes and Spatial Patterns in the Upper Heihe Basin in China

    OpenAIRE

    Bing Gao; Yue Qin; Yuhan Wang; Dawen Yang; Yuanrun Zheng

    2015-01-01

    The Heihe River is the second largest inland basin in China; runoff in the upper reach greatly affects the socio-economic development in the downstream area. The relationship between spatial vegetation patterns and catchment hydrological processes in the upper Heihe basin has remained unclear to date. In this study, a distributed ecohydrological model is developed to simulate the hydrological processes with vegetation dynamics in the upper Heihe basin. The model is validated by hydrological o...

  2. Hydrologic predictions on ungauged catchments using deterministic distributed modelling system

    Science.gov (United States)

    Tachecí, Pavel; Kimlová, Martina

    2010-05-01

    There is a need for warning system giving prediction of flash-flood risk conditions with sufficient advance even in source areas and in small tributaries catchments. New approach is based on combination of numerical weather prediction (NWP) model, radar or rain gauge data with distributed hydrologic mathematical model of particular area. Set of newly developed tools, customized for particular use in the Czech Hydrometeorological Institute (CHMI) environment enhance import of data and presentation of results. This forecast system focuses on hydrological modelling of running water balance in spatially distributed manner. Its computation is repeated day-to-day. Six models of particular basins (800 - 4000 km2), representing different conditions across the Czech Republic territory were calibrated and validated successfully. The Sázava river basin model (4.000 km2) is used for regular testing operation in CHMI Forecast centre since October 2007. Basic size of grid cells used in models is 300x300 m, basic time step of forecast is 1 day, but can be refined according to the input data. Water balance is computed using simplified 2-layer method for unsaturated zone, 2D approximation of Boussinesq equation for saturated zone, diffusion equation for overland flow and 1D kinematic equation for river flow (MIKE 11 model). The whole process of input data processing, model simulation and result generation may be run automatically or in step-by step mode via simple graphical user interface. Three types of input data are supported: •time series (temperature and precipitation) measured at observation stations and stored in CHMI database •radar data products (precipitation intensity field) •results of ALADIN weather forecast model (temperature and precipitation field). For forecast purposes, reference evapotranspiration is approximated according relationship to air temperature for every computational grid cell. The user may choose area (catchment) to be processed and period of

  3. Modelling fate and transport of glyphosate and AMPA in the Meuse catchment to assess the contribution of different pollution sources

    Science.gov (United States)

    Desmet, Nele; Seuntjens, Piet

    2013-04-01

    Large river basins have multiple sources of pesticides and usually the pollution sources are spread over the entire catchment. The cumulative effect of pesticides entering the river system in upstream areas and the formation of persistent degradation products can compromise downstream water use e.g. raw water quality for drinking water abstractions. For assessments at catchment scale pesticide fluxes coming from different sources and sub basins need to be taken into account. To improve management strategies, a sound understanding of the sources, emission routes, transport, environmental fate and conversion of pesticides is needed. In the Netherlands, the Meuse river basin is an important source for drinking water production. The river suffers from elevated concentrations of glyphosate and aminomethylphosphonic acid (AMPA). For AMPA it is rather unclear to what extent the pollution is related to glyphosate degradation and what is the contribution of other sources, especial phosphonates in domestic and industrial waste water. Based on the available monitoring data only it is difficult to distinguish between AMPA sources in such a large river basin. This hampers interpretation and decision making for water quality management in the Meuse catchment. Here, application of water quality models is very useful to obtain complementary information and insights. Modelling allows accounting for temporal and spatial variability in discharge and concentrations as well as distinguishing the contribution from conversion processes. In this study, a model for the river Meuse was developed and applied to assess the contribution of tributary and transnational influxes, glyphosate degradation and other sources to the AMPA pollution.

  4. Using 137Cs measurements to validate the application of the AGNPS and ANSWERS erosion and sediment yield models in two small Devon catchments

    International Nuclear Information System (INIS)

    Distributed erosion and sediment yield models are being increasingly used for predicting soil erosion and sediment yields in agricultural catchments. In most applications, validation of such models has commonly been restricted to comparison of the predicted and measured sediment output from a catchment, because spatially distributed information on rates and patterns of soil redistribution within the catchment has been lacking. However, such spatially distributed data are needed for rigorous model testing, in order to validate the internal functioning of a model and its applicability at different spatial scales. The study reported in this paper uses two approaches to test the performance of the agricultural non-point source pollution (AGNPS) and areal non-point source watershed environmental response simulation (ANSWERS) erosion and sediment yield models in two small catchments in Devon, UK. These involve, firstly, comparison of observed and predicted runoff and sediment output data for individual storm events monitored at the basin outlets and, secondly, information on the spatial pattern of soil redistribution within the catchments derived from 137Cs measurements. The results obtained indicate that catchment outputs simulated by both models are reasonably consistent with the recorded values, although the AGNPS model appears to provide closer agreement between observed and predicted values. However, the spatial patterns of soil redistribution and the sediment delivery ratios predicted for the two catchments by the AGNPS and ANSWERS models differ significantly. Comparison of the catchment sediment delivery ratios and the pattern of soil redistribution in individual fields predicted by the models with equivalent information derived from 137Cs measurements indicates that the AGNPS model provides more meaningful predictions of erosion and sediment yield under UK conditions than the ANSWERS model and emphasises the importance of using information on both catchment

  5. Sediment sources and storages in the urbanizing South Creek catchment, Lake Macquarie, NSW

    International Nuclear Information System (INIS)

    An investigation of the sediment source areas and sediment storages has been undertaken in the South Creek catchment, Lake Macquarie, NSW. Source areas have been examined by analyzing suspended sediment concentrations, field measurements and observations, and caesium-137 values. The caesium-137 technique and field measurements were used to study the sediment storages on the South Creek flood plain. Particle size analysis of sediments on the slopes and flood plain were undertaken to provide information on the efficiency of the sediment transport system. The results of these investigations indicate that the developing urban areas are the main sources of poorest water quality (in terms of suspended sediment) in the South Creek catchment. The open woodland, rural and established urban areas were minor sediment source areas, although the open woodland had the potential to become a major sediment source if disturbed by human activities. The developing urban areas had efficient sediment transport systems, while the open woodland and rural areas tended to deposit sediment locally. The upstream section of the flood plain was found to be storing more sediment than the downstream section. The study revealed that when urban development occurs on the steeper gradients of the South Creek catchment erosion processes are greatly accelerated and thus the developing urban area becomes the major source of poorest water quality in the catchment. The importance of the developing urban area as a sediment source needs to be considered in any future land developments in urbanizing drainage basins

  6. Impact Assessment of Uncertainty Propagation of Ensemble NWP Rainfall to Flood Forecasting with Catchment Scale

    Directory of Open Access Journals (Sweden)

    Wansik Yu

    2016-01-01

    Full Text Available The common approach to quantifying the precipitation forecast uncertainty is ensemble simulations where a numerical weather prediction (NWP model is run for a number of cases with slightly different initial conditions. In practice, the spread of ensemble members in terms of flood discharge is used as a measure of forecast uncertainty due to uncertain precipitation forecasts. This study presents the uncertainty propagation of rainfall forecast into hydrological response with catchment scale through distributed rainfall-runoff modeling based on the forecasted ensemble rainfall of NWP model. At first, forecast rainfall error based on the BIAS is compared with flood forecast error to assess the error propagation. Second, the variability of flood forecast uncertainty according to catchment scale is discussed using ensemble spread. Then we also assess the flood forecast uncertainty with catchment scale using an estimation regression equation between ensemble rainfall BIAS and discharge BIAS. Finally, the flood forecast uncertainty with RMSE using specific discharge in catchment scale is discussed. Our study is carried out and verified using the largest flood event by typhoon “Talas” of 2011 over the 33 subcatchments of Shingu river basin (2,360 km2, which is located in the Kii Peninsula, Japan.

  7. CATCHMENT-WIDE ANALYSIS OF THE SEDIMENT REGIME WITH RESPECT TO RESERVOIR SEDIMENTATION

    Institute of Scientific and Technical Information of China (English)

    Helmut M. HABERSACK; Konrad BOGNER; Josef SCHNEIDER; Michael BRAUNER

    2001-01-01

    The aim of this paper is to discuss a catchment-wide approach for analysing the sediment regime with respect to reservoir sedimentation, based on the Alpine Solk-basin in Austria. On a scaling perspective the boundary conditions and major processes of a catchment, like the geomorphological setting, are given by longterm developments. On the basis of field mapping these effects are discussed with respect to sediment availability, being affected e.g. by deep-seated gravitational slope deformations and slope creeping. Within these longterm processes, short-term unsteady sediment supply, erosion, transfer, deposition and remobilisation processes determine reservoir sedimentation and management. An intensive field monitoring program, including bedload and suspended sediment measurements, supplies data for the subsequent rainfall-runoff-erosion and sediment transport modeling (input, calibration and validation data). Instead of aiming to predict sediment transport processes in a purely deterministic manner the use of stochastic concepts allows to define locations in the catchment with a high probability for delivering significant amounts of sediments to the channels and finally the reservoir. Results show that landuse, channel regulation and avalanches are of great importance for sediment supply and that catchment management (beside managing the reservoir itself)has to address these.

  8. Spectral Analysis in Catchment Hydrology and Geochemistry

    Science.gov (United States)

    Kirchner, J. W.; Feng, X.; Renshaw, C. E.; Neal, C.

    2001-12-01

    Spectral analysis of chemical tracer time series can be used to probe the internal workings of catchments. It has recently been shown that catchments act as fractal filters for inert chemical tracers like chloride, converting "white noise" rainfall chemistry inputs into fractal "1/f noise" runoff chemistry time series (Kirchner et al., 2000). This implies that catchments have long-tailed travel time distributions, and thus retain soluble contaminants for unexpectedly long timespans. Long-term monitoring data from North America, Britain, and Scandinavia show that this fractal behavior characterizes a wide array of catchments. How can this fractal scaling arise in such diverse settings? One can show that advection and dispersion of spatially distributed rainfall tracer inputs will generate fractal tracer time series, as long as the flow system is highly dispersive (Kirchner et al., in press). This implies that subsurface flow in small catchments is dominated by large conductivity contrasts, such as arise from macropores, fracture networks, and similar large-scale heterogeneities in subsurface conductivity. One can also use spectral methods to analyze long-term time series of water fluxes in rainfall and streamflow. Spectral analysis of hydrologic time series measures the downslope propagation of the hydraulic potential waves that mobilize runoff, whereas spectral analysis of tracer time series clocks the propagation of water itself through the catchment. Water fluxes in streamflow exhibit non-fractal scaling, instead of the fractal 1/f scaling shown by chemical tracers. These observations imply that hydrologic signals are transmitted downslope more rapidly, and with much less dispersion, than chemical tracer signals are. Thus small upland catchments transmit hydraulic potentials (which drive runoff) much less dispersively than they transport water itself. These observations provide important constraints for theoretical models of subsurface flow and transport in

  9. Catchment compatibility via copulas: A non-parametric study of the dependence structures of hydrological responses

    Science.gov (United States)

    Grimaldi, S.; Petroselli, A.; Salvadori, G.; De Michele, C.

    2016-04-01

    The similarity of catchment responses is a fundamental issue for regionalization studies, and hydrograph attributes (i.e., Discharge Peak, Volume, and Duration) can reveal the signature and the synthesis of local scale processes. Here, we focus the attention on the "compatibility" between catchments, viz. on the possibility to transfer, from one catchment to another, the information about the dependence structures at play. In particular, we statistically investigate the possible relationships between the features of different Basin Scenarios (characterized via the Concentration Time Tc and the Curve Number CN) and the corresponding dependence structures ruling the joint statistics of Discharge, Volume, and Duration. Given a large set of synthetic runoff time series, generated via a rainfall-runoff model, recent non-parametric tests, based on empirical copulas, are used to compare the dependence structures associated with different soil uses and concentration times. The results indicate how the hydrological properties may affect the dependence structure. The outcomes of the investigation could be particularly effective in two practical applications: (1) for determining the degree of compatibility of the dependence structures associated with different basin scenarios, and (2) for enriching scanty data bases, in order to improve the estimation of multivariate copulas.

  10. Socio-hydrological water balance for water allocation between human and environmental purposes in catchments

    Science.gov (United States)

    Zhou, S.; Huang, Y.; Wei, Y.; Wang, G.

    2015-08-01

    Rebalancing water allocation between human consumptive uses and the environment in water catchments is a global challenge. This paper proposes a socio-hydrological water balance framework by partitioning catchment total evapotranspiration (ET) into ET for society and ET for natural ecological systems, and establishing the linkage between the changes of water balance and its social drivers and resulting environmental consequences in the Murray-Darling Basin (MDB), Australia, over the period 1900-2010. The results show that the 100-year period of water management in the MDB could be divided into four periods corresponding to major changes in basin management within the socio-hydrological water balance framework: period 1 (1900-1956) - expansion of water and land use for the societal system, period 2 (1956-1978) - maximization of water and land use for the societal system, period 3 (1978-2002) - maximization of water use for the societal system from water diversion, and period 4 (2002-present) - rebalancing of water and land use between the societal and ecological systems. Most of management changes in the MDB were passive and responsive. A precautionary approach to water allocation between the societal and ecological systems should be developed. The socio-hydrological water balance framework could serve as a theoretical foundation for water allocation to evaluate the dynamic balance between the societal and ecological systems in catchments.

  11. Runoff evolution according to land use change in a small Sahelian catchment

    Directory of Open Access Journals (Sweden)

    L. Descroix

    2011-02-01

    Full Text Available Significant land use changes have been observed in West Africa, particularly in the Sahel region where climatic and demographic factors have led to a rise in cultivated areas, in recent decades. These changes caused strong modifications in the water cycle and in river regimes.

    By comparing the rainfall-runoff relationships for two periods (1991–1994 and 2004–2010 in two small neighbouring catchments (approx. 0.1 km2 each of the Sahel, this study highlights the different hydrological consequences of land use change, particularly vegetation clearing and the consequent degradation of topsoil.

    Runoff increased in the upper basin, while it decreased in the lower basin, due to a strong increase in in-channel infiltration. Flood peak durations have become shorter in the downstream part of the catchment due to the huge increase of runoff water transmission losses within the gullies.

    Further study will consist of equipping one of the catchments with anti-erosion devices (mainly "half-moons" and terraces in order to evaluate the influence of anti-erosion devices on runoff and suspended load.

  12. Controls on diurnal streamflow cycles in a high altitude catchment in the Swiss Alps

    Science.gov (United States)

    Mutzner, R.; Weijs, S. V.; Tarolli, P.; Calaf, M.; Oldroyd, H. J.; Parlange, M. B.

    2014-12-01

    The study of streamflow diurnal cycles is of primary importance to understand hydrological processes happening at various spatial scales. In high altitude alpine catchments, streamflow diurnal cycles are typically dominated by snow or icemelt. During a field campaign in the summer 2012 in a small catchment in the Swiss Alps (Val Ferret catchment, draining area of 20.4 km2, mean altitude of 2423 m above sea level (asl), ranging from 1773 m to 3206 m asl, glaciarized area: 2%), we observed streamflow diurnal cycles throughout the season in two monitored sub-basins of the watershed. To study in detail the diurnal cycles, we make use of a wireless network of meteorological stations, time-lapse photography, a fully equipped energy-balance station and water electrical conductivity monitored at the gauging stations. In the first sub-basin, we observed a transition from a snowmelt to an evapotranspiration induced diurnal streamflow cycle. In the second sub-basin, we observed a snowmelt/icemelt dominated diurnal cycle during the entire season due to the presence of a small glacier. Comparisons between icemelt and evapotranspiration cycles showed that the two processes were happening at the same times of day but with a different sign. The amplitude of the icemelt cycle decreased exponentially during the season and was larger than of the amplitude of the evapotranspiration cycle which was relatively constant during the season. A conceptual model was applied to estimate the effect of evapotranspiration on the diurnal streamflow cycle in the icemelt dominated sub-basin. The model makes use of the latent heat measured at the energy balance station, the streamflow loss due to evapotranspiration and the computation of active evapotranspiration areas. Our study suggests that evapotranspiration from the riparian area damps the icemelt-diurnal streamflow cycle resulting in a possible underestimation of glacier mass changes.

  13. Catchment Dispersion Mechanisms in an Urban Context

    Science.gov (United States)

    Gironas, J. A.; Mejia, A.; Rossel, F.; Rinaldo, A.; Rodriguez, F.

    2014-12-01

    Dispersion mechanisms have been examined in-depth in natural catchments in previous studies. However, these dispersion mechanisms have been studied little in urban catchments, where artificial transport elements and morphological arrangements are expected to modify travel times and mobilize excess rainfall from spatially distributed impervious sites. Thus, these features can modify the variance of the catchment's travel times and hence the total dispersion. This work quantifies the dispersion mechanisms in an urban catchment using the theory of transport by travel times as represented by the Urban Morpho-climatic Instantaneous Unit Hydrograph (U-McIUH) model. This model computes travel times based on kinematic wave theory and accounts explicitly for the path heterogeneities and altered connectivity patterns characteristic of an urban drainage network. The analysis is illustrated using the Aubinière urban catchment (France) as a case study. We found that kinematic dispersion is dominant for small rainfall intensities, whereas geomorphologic dispersion becomes more dominant for larger intensities. The total dispersion scales with the drainage area in a power law fashion. The kinematic dispersion is dominant across spatial scales up to a threshold of approximately 2-3 km2, after which the geomorphologic dispersion becomes more dominant. Overall, overland flow is responsible for most of the dispersion, while conduits tend to counteract the increase of the geomorphologic dispersion with a negative kinematic dispersion. Further studies with other catchments are needed to assess whether the latter is a general feature of urban drainage networks.

  14. Catchments as simple dynamical systems: A case study on methods and data requirements for parameter identification

    Science.gov (United States)

    Melsen, Lieke; Teuling, Adriaan; van Berkum, Sonja; Torfs, Paul; Uijlenhoet, Remko

    2014-05-01

    In many rainfall-runoff models at least some calibration of model parameters has to take place. Especially for ungauged or poorly gauged basins this can be problematic, because there is little or no data available for calibration. A possible solution to overcome the problems caused by data scarcity is to set up a measurement campaign for a short time period. With the employed approach based on the theory of Kirchner (2009), a model was developed and applied to the Rietholzbach catchment in Switzerland (Teuling et al., 2010, Seneviratne et al., 2012), with only two parameters. These two parameters describe a unique storage-discharge relation. The model is constructed such that the parameters can be determined not only with automatic calibration, but also by recession analysis and a priori from Boussinesq theory. The automatic calibration and the recession analysis have been fed with different selections of the full data record as well as with the full data record itself. For Boussinesq theory, catchment characteristics were given as required input. In the end, a comparison of the performance of the three different methods was made, and a comparison on the amount of data that is required by each of the three parameter identification methods. Melsen, L.A., Teuling, A.J., van Berkum, S.W., Torfs, P.J.J.F., Uijlenhoet, R. (2013) Catchments as simple dynamical systems: A case study on methods and data requirements for parameter identification, Water Resour. Res., under review References Kirchner, J.W. (2009), Catchments as simple dynamical systems: Catchment characterization, rainfall-runoff modeling, and doing hydrology backward, Water Resour. Res. 45:W02429. Seneviratne, S.I., I. Lehner, J. Gurtz, A.J. Teuling, H Lang, U. Moser, D. Grebner, L. Menzel, K. Schro, T. Vitvar, and M. Zappa (2012), Swiss prealpine Rietholzbach research catchment and lysimeter: 32 year time series and 2003 drought event, Water Resour. Res. 48:W06526. Teuling, A. J., I. Lehner, J. W. Kirchner

  15. The precipitation-/runoff model ZEMOKOST: development of a practical model for the determination of flood runoff in the catchment areas of torrents, including improved data field

    International Nuclear Information System (INIS)

    In hydrology a basic task is the estimation of design discharges and runoff changes in ungauged catchments. However, traditional empirical rules of thumb as well as regionalization of measured discharges are subject to uncertainty. It seems that precipitation-runoff modelling is the only comprehensible way to predict discharge alterations due to changes in ungauged basins, even though the results are perhaps not less uncertain. In order to minimize this uncertainty this work presents a new methodology for discharge estimation in ungauged basins by introducing runoff coefficients derived from field assessment, by a new adapted precipitation-runoff model (ZEMOKOST) and routines for a plausibility check. Subsequently ten gauged Austrian catchments were used as hypothetical ungauged catchments for application and verification of this method. Except for special questions in karst- and glacier-hydrology the procedure showed satisfying results. (author)

  16. RUNOFF POTENTIAL OF MUREŞ RIVER UPPER BASIN TRIBUTARIES

    Directory of Open Access Journals (Sweden)

    V. SOROCOVSCHI

    2012-03-01

    Full Text Available Runoff Potential of Mureş River Upper Basin Tributaries. The upper basin of the Mureş River includes a significant area of the Eastern Carpathians central western part with different runoff formation conditions. In assessing the average annual runoff potential we used data from six gauging stations and made assessments on three distinct periods. Identifying the appropriate areas of the obtained correlations curves (between specific average runoff and catchments mean altitude allowed the assessment of potential runoff at catchment level and on geographical units. The potential average runoff is also assessed on altitude intervals of the mentioned areas. The runoff potential analysis on hydrographic basins, geographical units and altitude intervals highlights the variant spatial distribution of this general water resources indicator in the different studied areas.

  17. Detecting runoff variation in Weihe River basin, China

    Science.gov (United States)

    Jingjing, F.; Qiang, H.; Shen, C.; Aijun, G.

    2015-05-01

    Dramatic changes in hydrological factors in the Weihe River basin are analysed. These changes have exacerbated ecological problems and caused severe water shortages for agriculture, industries and the human population in the region, but their drivers are uncertain. The Mann-Kendall test, accumulated departure analysis, sequential clustering and the sliding t-test methods were used to identify the causes of changes in precipitation and runoff in the Weihe basin. Change-points were identified in the precipitation and runoff records for all sub-catchments. For runoff, the change in trend was most pronounced during the 1990s, whereas changes in precipitation were more prominent earlier. The results indicate that human activities have had a greater impact than climate change on the hydrology of the Weihe basin. These findings have significant implications for the establishment of effective strategies to counter adverse effects of hydrological changes in the catchment.

  18. An Open-Source Approach for Catchment's Physiographic Characterization

    Science.gov (United States)

    Di Leo, M.; Di Stefano, M.

    2013-12-01

    A water catchment's hydrologic response is intimately linked to its morphological shape, which is a signature on the landscape of the particular climate conditions that generated the hydrographic basin over time. Furthermore, geomorphologic structures influence hydrologic regimes and land cover (vegetation). For these reasons, a basin's characterization is a fundamental element in hydrological studies. Physiographic descriptors have been extracted manually for long time, but currently Geographic Information System (GIS) tools ease such task by offering a powerful instrument for hydrologists to save time and improve accuracy of result. Here we present a program combining the flexibility of the Python programming language with the reliability of GRASS GIS, which automatically performing the catchment's physiographic characterization. GRASS (Geographic Resource Analysis Support System) is a Free and Open Source GIS, that today can look back on 30 years of successful development in geospatial data management and analysis, image processing, graphics and maps production, spatial modeling and visualization. The recent development of new hydrologic tools, coupled with the tremendous boost in the existing flow routing algorithms, reduced the computational time and made GRASS a complete toolset for hydrological analysis even for large datasets. The tool presented here is a module called r.basin, based on GRASS' traditional nomenclature, where the "r" stands for "raster", and it is available for GRASS version 6.x and more recently for GRASS 7. As input it uses a Digital Elevation Model and the coordinates of the outlet, and, powered by the recently developed r.stream.* hydrological tools, it performs the flow calculation, delimits the basin's boundaries and extracts the drainage network, returning the flow direction and accumulation, the distance to outlet and the hill slopes length maps. Based on those maps, it calculates hydrologically meaningful shape factors and

  19. Partitioning of catchment water budget and its implications for ecosystem carbon exchange

    Directory of Open Access Journals (Sweden)

    D. Lee

    2009-12-01

    Full Text Available Spatially averaged annual carbon budget is one of the key information to understand ecosystem response and feedback to climate change. Water availability is a primary constraint of carbon uptake in many ecosystems and therefore the estimation of transpiration (T may serve as an alternative to quantify carbon budget. To apply this concept, we estimated long-term steady state water budget for the Han River basin (~26 000 km2 in Korea and examined its implication for catchment scale carbon exchange. For this, the catchment scale evapotranspiration (ET was derived from the long term precipitation (P and discharge (Q data. Then, using stable isotope data of P and Q along with hydrometeorological information, ET was partitioned into evaporation from soil and water surfaces (ES, evaporation from intercepted rainfall (El, and transpiration. ES was identified as a minor component of ET in the study areas regardless of the catchment scales. T was estimated from ET after accounting for El and ES. For the Han River basin, the estimated annual T from 1966 to 2007 was 22–31% of annual P and the proportion decreased with increasing P. Assuming that T further constrains catchment scale carbon uptake in terms of water use efficiency (WUE, we examined the possibility of using T as a relative measure for the strength and temporal changes of carbon uptake capacity. The proposed relations provide a simple and practical way to assess the distribution and strength of carbon sink.

  20. Snow cover trend and hydrological characteristics of the Astore River basin (Western Himalayas) and its comparison to the Hunza basin (Karakoram region).

    Science.gov (United States)

    Tahir, Adnan Ahmad; Chevallier, Pierre; Arnaud, Yves; Ashraf, Muhammad; Bhatti, Muhammad Tousif

    2015-02-01

    A large proportion of Pakistan's irrigation water supply is taken from the Upper Indus River Basin (UIB) in the Himalaya-Karakoram-Hindukush range. More than half of the annual flow in the UIB is contributed by five of its snow and glacier-fed sub-basins including the Astore (Western Himalaya - south latitude of the UIB) and Hunza (Central Karakoram - north latitude of the UIB) River basins. Studying the snow cover, its spatio-temporal change and the hydrological response of these sub-basins is important so as to better manage water resources. This paper compares new data from the Astore River basin (mean catchment elevation, 4100 m above sea level; m asl afterwards), obtained using MODIS satellite snow cover images, with data from a previously-studied high-altitude basin, the Hunza (mean catchment elevation, 4650 m asl). The hydrological regime of this sub-catchment was analyzed using the hydrological and climate data available at different altitudes from the basin area. The results suggest that the UIB is a region undergoing a stable or slightly increasing trend of snow cover in the southern (Western Himalayas) and northern (Central Karakoram) parts. Discharge from the UIB is a combination of snow and glacier melt with rainfall-runoff at southern part, but snow and glacier melt are dominant at the northern part of the catchment. Similar snow cover trends (stable or slightly increasing) but different river flow trends (increasing in Astore and decreasing in Hunza) suggest a sub-catchment level study of the UIB to understand thoroughly its hydrological behavior for better flood forecasting and water resources management. PMID:25461078

  1. Erosivity, surface runoff, and soil erosion estimation using GIS-coupled runoff-erosion model in the Mamuaba catchment, Brazil.

    Science.gov (United States)

    Marques da Silva, Richarde; Guimarães Santos, Celso Augusto; Carneiro de Lima Silva, Valeriano; Pereira e Silva, Leonardo

    2013-11-01

    This study evaluates erosivity, surface runoff generation, and soil erosion rates for Mamuaba catchment, sub-catchment of Gramame River basin (Brazil) by using the ArcView Soil and Water Assessment Tool (AvSWAT) model. Calibration and validation of the model was performed on monthly basis, and it could simulate surface runoff and soil erosion to a good level of accuracy. Daily rainfall data between 1969 and 1989 from six rain gauges were used, and the monthly rainfall erosivity of each station was computed for all the studied years. In order to evaluate the calibration and validation of the model, monthly runoff data between January 1978 and April 1982 from one runoff gauge were used as well. The estimated soil loss rates were also realistic when compared to what can be observed in the field and to results from previous studies around of catchment. The long-term average soil loss was estimated at 9.4 t ha(-1) year(-1); most of the area of the catchment (60%) was predicted to suffer from a low- to moderate-erosion risk (catchment, the soil erosion was estimated to exceed > 12 t ha(-1) year(-1). Expectedly, estimated soil loss was significantly correlated with measured rainfall and simulated surface runoff. Based on the estimated soil loss rates, the catchment was divided into four priority categories (low, moderate, high and very high) for conservation intervention. The study demonstrates that the AvSWAT model provides a useful tool for soil erosion assessment from catchments and facilitates the planning for a sustainable land management in northeastern Brazil. PMID:23652539

  2. Testing the transferability of regression equations derived from small sub-catchments to a large area in central Sweden

    Directory of Open Access Journals (Sweden)

    C. Xu

    2003-01-01

    Full Text Available There is an ever increasing need to apply hydrological models to catchments where streamflow data are unavailable or to large geographical regions where calibration is not feasible. Estimation of model parameters from spatial physical data is the key issue in the development and application of hydrological models at various scales. To investigate the suitability of transferring the regression equations relating model parameters to physical characteristics developed from small sub-catchments to a large region for estimating model parameters, a conceptual snow and water balance model was optimised on all the sub-catchments in the region. A multiple regression analysis related model parameters to physical data for the catchments and the regression equations derived from the small sub-catchments were used to calculate regional parameter values for the large basin using spatially aggregated physical data. For the model tested, the results support the suitability of transferring the regression equations to the larger region. Keywords: water balance modelling,large scale, multiple regression, regionalisation

  3. Response of paleofloods to climate variability in alpine catchments of different size reconstructed from floodplain sediments. Similarities or differences?

    Science.gov (United States)

    Schulte, Lothar; Carvalho, Filipe; Llorca, Jaime; Monterrubio, Glòria; Peña, Juan Carlos; Cabrera-Medina, Paula; Gómez-Bolea, Antonio; Sánchez-García, Carlos

    2016-04-01

    Continuous palaeohydrological time series are generally attributed to lake sediments rather than to those of fluvial sediments. However, most of the alpine lakes analysed are fed by small catchments (few km2). Recent studies show the high potential of flood reconstruction form sedimentary floodplain proxies of mid-size catchments (hundreds of km2) when calibrated by historical sources or other markers. Despite of different catchment sizes, flood pulses achieved from lake and flood plain sediments coincides in some cases. Nevertheless, these correlations must not be taken for granted, because catchment response can be strongly influenced by local physiographic and climatic parameters such as the unequal spatial distribution of precipitation caused by summer thunderstorms and advective rainfall events. To contribute to this discussion, our study investigate new proxy data of three cores retrieved from a small basin in the Bernese Alps, fed by the alluvial fans of Eistlenbach (4 km2) and Farnigraben (2 km2) which were compared with the floodplain records from the nearby Aare (596 km2) and Lütschine (379 km2) catchments. Following the same methodology developed previously in the other alpine basins, a 3200-yr long flood series were reconstructed from sedimentary and geochemical data applying XRF-core scan techniques, conventional XRF, LOI and grain size analysis. Flood pulses were identified by 30 flood layers, and a higher number of Zr/Ti, Sr/Ti, Ca/Ti peaks and Factor 1 scores. Modern flood signals were calibrated by historical sources, maps, aerial photographs and instrumental data. Not all events were recorded by coarse-grained beds because of the spatial variations of alluvial fan channels and their connectivity to the small distal basin. Recurrence intervals of the tipping points of the fan channel oscillation are traced by key changes of sedimentation rates and facies. However, geochemical proxies correlate not only very close with the historical local data

  4. Human impacts on river water quality- comparative research in the catchment areas of the Tone River and the Mur River-

    Science.gov (United States)

    Kogure, K.

    2013-12-01

    Human activities in river basin affect river water quality as water discharges into river with pollutant after we use it. By detecting pollutants source, pathway, and influential factor of human activities, it will be possible to consider proper river basin management. In this study, material flow analysis was done first and then nutrient emission modeling by MONERIS was conducted. So as to clarify land use contribution and climate condition, comparison of Japanese and European river basin area has been made. The model MONERIS (MOdelling Nutrient Emissions in RIver Systems; Behrendt et al., 2000) was applied to estimate the nutrient emissions in the Danube river basin by point sources and various diffuse pathways. Work for the Mur River Basin in Austria was already carried out by the Institute of Water Quality, Resources and Waste Management at the Vienna University of Technology. This study treats data collection, modelling for the Tone River in Japan, and comparative analysis for these two river basins. The estimation of the nutrient emissions was carried out for 11 different sub catchment areas covering the Tone River Basin for the time period 2000 to 2006. TN emissions into the Tone river basin were 51 kt/y. 67% was via ground water and dominant for all sub catchments. Urban area was also important emission pathway. Human effect is observed in urban structure and agricultural activity. Water supply and sewer system make urban water cycle with pipeline structure. Excess evapotranspiration in arable land is also influential in water cycle. As share of arable land is 37% and there provides agricultural products, it is thought that N emission from agricultural activity is main pollution source. Assumption case of 10% N surplus was simulated and the result was 99% identical to the actual. Even though N surplus reduction does not show drastic impact on N emission, it is of importance to reduce excess of fertilization and to encourage effective agricultural activity

  5. Evaluating hydrological ensemble predictions using a large and varied set of catchments (Invited)

    Science.gov (United States)

    Ramos, M.; Andreassian, V.; Perrin, C.; Loumagne, C.

    2010-12-01

    It is widely accepted that local and national operational early warning systems can play a key role in mitigating flood damage and losses to society while improving risk awareness and flood preparedness. Over the last years, special attention has been paid to efficiently couple meteorological and hydrological warning systems to track uncertainty and achieve longer lead times in hydrological forecasting. Several national and international scientific programs have focused on the pre-operational test and development of ensemble hydrological forecasting. Based on the lumped soil-moisture-accounting type rainfall-runoff model GRP, developed at Cemagref, we have set up a research tool for ensemble forecasting and conducted several studies to evaluate the quality of streamflow forecasts. The model has been driven by available archives of weather ensemble prediction systems from different sources (Météo-France, ECMWF, TIGGE archive). Our approach has sought to combine overall validation under varied geographical and climate conditions (to assess model robustness and generality) and site-specific validation (to locally accept or reject the hydrologic forecast system and contribute to defining its limits of applicability). The general aim is to contribute to methodological developments concerning a wide range of key aspects in hydrological forecasting, including: the links between predictability skill and catchment characteristics, the magnitude and the distribution of forecasting errors, the analysis of nested or neighbouring catchments for prediction in ungauged basins, as well as the reliability of model predictions when forecasting under conditions not previously encountered during the period of setup and calibration of the system. This presentation will cover the aforementioned topics and present examples from studies carried out to evaluate and inter-compare ensemble forecasting systems using a large and varied set of catchments in France. The specific need to

  6. Water balance modeling of Upper Blue Nile catchments using a top-down approach

    Directory of Open Access Journals (Sweden)

    S. Tekleab

    2011-07-01

    Full Text Available The water balances of twenty catchments in the Upper Blue Nile basin have been analyzed using a top-down modeling approach based on Budyko's hypotheses. The objective of this study is to obtain better understanding of water balance dynamics of upper Blue Nile catchments on annual and monthly time scales and on a spatial scale of meso scale to large scale. The water balance analysis using a Budyko-type curve at annual scale reveals that the aridity index does not exert a first order control in most of the catchments. This implies the need to increase model complexity to monthly time scale to include the effects of seasonal soil moisture dynamics. The dynamic water balance model used in this study predicts the direct runoff and other processes based on the limit concept; i.e. for dry environments since rainfall amount is small, the aridity index approaches to infinity or equivalently evaporation approaches rainfall and for wet environments where the rainfall amount is large, the aridity index approaches to zero and actual evaporation approaches the potential evaporation. The uncertainty of model parameters has been assessed using the GLUE (Generalized Likelihood Uncertainty Estimation methodology. The results show that the majority of the parameters are reasonably well identifiable. However, the baseflow recession constant was poorly identifiable. Parameter uncertainty and model structural errors could be the reason for the poorly identifiable parameter. Moreover, a multi-objective model calibration strategy has been employed to emphasize the different aspects of the hydrographs on low and high flows.

    The model has been calibrated and validated against observed streamflow time series and it shows good performance for the twenty study catchments in the upper Blue Nile. During the calibration period (1995–2000 the Nash and Sutcliffe efficiency (E NS for monthly flow prediction varied between 0.52 to 0.93 (dominated by

  7. Sound management of sediment yields at the catchment scale by small detention ponds

    Science.gov (United States)

    Sikorska, A. E.; Wasilewicz, M.; Banasik, K.

    2012-04-01

    Keywords: small detention pond, sediment deposits, reservoir silting, urban catchment Globally observed land use and climate changes have a clear impact on the sediment yields deriving from the catchment. Released sediments may originate from different point and non-point sources. Thereby it is difficult to manage and reduce sediment loads directly at the source without undertaking detailed and expensive monitoring programs. Small detention ponds are therefore frequently used water management systems in urban settlements to improve water quality at the catchment scale. Such ponds located at the outlet of small basins allow reducing sediment loads downstream. Additionally, they capture sediment-associated contaminants as heavy metals, nutrients and micropollutants. On the other hand, a sedimentation within the pond may be a severe problem because it decreases over the time its retention capacity. This is especially significant for small detention ponds, where the siltation rate is high. These ponds can loose their total capacity already after few years of their exploitation when no dredging operations are considered. Unfortunately, maintenance costs of small ponds are expensive and usually not taken into account when planning and constructing such ponds. Consequently, many small detention ponds become inefficient after an entire use of their capacity. Therefore careful planning of maintenance options is essential to keep an effectiveness of such ponds on the expected level. Within presented here study we addressed the problem of silting small detention ponds and we assessed an applicability of such ponds to manage sediment yields discharged from small urban catchments. To this end, a periodic measurement of deposited sediments within a small detention pond (1.35 ha, 5 years old, Warsaw, Poland) has been undertaken. This pond receives a polluted runoff from a small urbanized basin (30 km2), for which no routine sediment measurement exists. The spatial sediment

  8. Hydropedological insights when considering catchment classification

    Directory of Open Access Journals (Sweden)

    J. Bouma

    2011-02-01

    Full Text Available Soil classification systems are analysed in relation to the functioning and characterisation of catchments. Soil classifications are useful to create systematic order in the overwhelming quantity of different soils in the world and to extrapolate data available for a given soil type to soils elsewhere with identical classifications. However, such classifications are based on permanent characteristics as formed by the soil forming factors over often very long periods of time and this does not necessarily match with characteristics and parameters needed for functional soil characterization focusing, for example, on catchment hydrology. Hydropedology has made contributions towards functional characterization of soils as is illustrated for recent hydrological catchment studies. However, much still needs to be learned about the physical behaviour of anisotropic, heterogeneous field soils with varying soil structures during the year and the suggestion is made to first focus on improving simulation of catchment hydrology, incorporating hydropedological expertise, before embarking on a classification effort which involves major input of time and involves the risk of distraction. In doing so, we advise to also define other characteristics for catchment performance than the traditionally measured discharge rates.

  9. Exceptional hydrological phenomena in the Gemenea catchment

    Directory of Open Access Journals (Sweden)

    Florentina LIVARCIUC

    2015-10-01

    Full Text Available Flash floods, accompanied by high waters and regular floods, represent the most dangerous natural hazards in the Gemenea catchment, inducing other risks such as geomorphologic, environmental, social and economical risks. Flash floods occurred during the 1969 to 2014 monitoring interval are characterized by extremely high discharge values, of 68.9 m3/s in 2006 and 95.3 m3/s in 2008 and a magnitude 2.5 times higher than the average discharge recorded until that timeframe. With an area of 77.7 km2, the Gemenea catchment falls into the category of small catchments, where the peak discharge during exceptional hydrological phenomena is caused by torrential rainfall. Flash floods of particularly high intensities caused serious damages through: total destruction or damage of the torrent correction works, clogging of culverts on catchment forest roads, failure of river banks and deterioration of the bridges that affected roads and homes in Gemenea, Slătioara and Stulpicani villages. These floods have also caused damage to the forest/agriculture fund through deep and lateral erosion, failure of river banks and landslides. Within this study we aim to emphasize the magnitude, frequency, duration and area of manifestation of such phenomena in the Gemenea catchment. Furthermore, we aim to advance our knowledge of the genesis and specific mechanisms of flash flood occurrence for reducing their negative impacts on the local environment and communities

  10. A simple hydrologic model for rapid prediction of runoff from ungauged coastal catchments

    Science.gov (United States)

    Wan, Yongshan; Konyha, Kenneth

    2015-09-01

    We developed a lumped conceptual rainfall-runoff model for rapid prediction of runoff generated in the unique hydrological setting with flat terrain, sandy soils, high groundwater table, and a dense drainage canal network in south Florida. The model is conceptualized as rainfall and evapotranspiration filling and emptying the root zone and excess rainfall recharging three storage zones. Outflows from these storage zones, routed with parallel arrangement of three linear reservoirs, represent different flow components of catchment runoff, i.e., slow drainage (shallow subsurface flow), medium drainage (interflow and saturation excess overland flow), and fast drainage (direct runoff from impervious urban areas or from water table management in agricultural land). The model is parsimonious with eight model parameters along with two optional water management parameters. A regionalization study was conducted through model parameterization to achieve target hydrological behavior of typical land uses, which are the most significant basin descriptor affecting catchment hydrology in south Florida. Cross validation with 16 gauged basins dominated by urban, agricultural, and natural lands, respectively, indicated that the model provides an effective tool for rapid prediction of runoff in ungauged basins using the regionalized model parameters. A case study is presented, involving application of the model to support real-time adaptive management to hydrological operations for protection of estuarine ecosystems.

  11. Understanding Polycyclic Aromatic Hydrocarbon transfers at the catchment scale combining chemical and fallout radionuclides analyses

    Science.gov (United States)

    Gateuille, David; Evrard, Olivier; Lefevre, Irène; Moreau-Guigon, Elodie; Alliot, fabrice; Chevreuil, Marc; Mouchel, Jean-Marie

    2013-04-01

    Contamination of river water and sediment constitutes a major environmental issue for industrialized countries. Polycyclic Aromatic Hydrocarbons (PAHs) are a group of persistent organic pollutants characterized by two or more fused rings. In recent years, studies dealing with PAHs have grown in number. Some PAHs present indeed a high risk for environment and human health because of their carcinogenic and mutagenic properties. However, most of these studies focused on measuring PAH concentration in the different compartments of the environment (air, soil, sediment, water, etc.) In this context, there remains a lack of understanding regarding the various processes responsible for PAH transfers from one environmental compartment to another. Our study aims to quantify PAHs transfers at the catchment scale by combining chemical analysis with gamma spectrometry. Air, soil, river water and sediment samples (n=820) were collected in two upstream sub-catchments of the Seine River basin (France) during one year. Chemical analyses were carried out to determine PAHs concentrations in all samples. Furthermore, measurement of fallout radionuclides (Beryllium-7, Lead-210, Caesium-137) in both rainfall and river sediment provided a way to discriminate between freshly eroded sediment vs. resuspension of older material that previously deposited on the riverbed. This information is crucial to estimate PAH residence time and transfer velocities in the Seine River basin. The results show that the PAH behaviour varies from one subcatchment to the next. PAH transfers depend indeed on both the characteristics of the catchment (e.g. topography, presence of drained cropland in catchments) and the local anthropogenic pressures. A significant increase in atmospheric deposition of PAHs is observed during winter due to a larger number of sources (household heating). The 14-month study has also highlighted the seasonal variations of PAH fluxes, which are mainly related to the hydrological

  12. PSYCHIC A process-based model of phosphorus and sediment transfers within agricultural catchments. Part 2. A preliminary evaluation

    Science.gov (United States)

    Strömqvist, J.; Collins, A. L.; Davison, P. S.; Lord, E. I.

    2008-02-01

    SummaryThis paper describes the preliminary evaluation of the PSYCHIC catchment scale (Tier 1) model for predicting the mobilisation and delivery of phosphorus (P) and suspended sediment (SS) in the Hampshire Avon (1715 km 2) and Herefordshire Wye (4017 km 2) drainage basins, in the UK, using empirical data. Phosphorus and SS transfers to watercourses in the Wye were predicted to be greater than corresponding delivery in the Avon; SS, 249 vs 33 kg ha -1 yr -1; DP, 2.57 vs 1.26 kg ha -1 yr -1; PP, 2.20 vs 0.56 kg ha -1 yr -1. The spatial pattern of the predicted transfers was relatively uniform across the Wye drainage basin, whilst in the Avon, delivery to watercourses was largely confined to the river corridors and small areas of drained land. Statistical performance in relation to predicted exports of P and SS, using criteria for relative error (RE) and root mean square error (RMSE), reflected the potential shortcomings associated with using longer-term climate data for predicting shorter-term (2002-2004) catchment response and the need to refine calculations of point source contributions and to incorporate additional river basin processes such as channel bank erosion and in-stream geochemical processing. PSYCHIC is therefore best suited to characterising longer-term catchment response.

  13. Estimation of groundwater contribution in runoff from small agricultural dominated catchments

    Science.gov (United States)

    Deelstra, Johannes; Jansons, Viesturs; Lagzdiņš, Ainis

    2013-04-01

    Latvia. Each set consisted of a field providing both surface and subsurface runoff located within the catchment. Different filters were tested but the one developed by Chapman & Maxwell (1996) was selected. An improved filter parameter value was obtained, resulting in more realistic values for BFI in Norwegian catchments, being in the order of 10%. The values for the Latvian catchments were slightly higher, the main reason for this being soil types and geological settings. The results indicate that care should be taken in selecting the digital filter value for catchments having flashy runoff behaviour. This might lead to wrong estimates of baseflow contribution which can have negative effects on modelling hydrology, pollutant transport and the selection of mitigation measures at the scale of small agricultural catchments. References Chapman, T.G., Maxwell, A.I . 1996. Baseflow separation - comparison of numerical methods with tracer experiments. Institute Engineers Australia National Conference. Publ. 96/05, 539-545 Deelstra, J., Eggestad, H.O., Iital, A., Jansons, V. and Barkved, L.J. (2010), "Time resolution and hydrological characteristics in agricultural catchments", in Hermann, A. and Schumann, S. (Eds), Status and Perspectives of Hydrology in Small Basins, Vol. 336, IAHS Publication, pp. 138 - 143.

  14. Elevational dependence of climate change impacts on water resources in an Alpine catchment

    Directory of Open Access Journals (Sweden)

    S. Fatichi

    2013-03-01

    Full Text Available An increasing interest is directed toward understanding impacts of climate change on water related sectors in a particularly vulnerable area such as the Alpine region. We present a distributed hydrological analysis at scale significant for water management for pristine, present-days, and projected future climate conditions. We used the upper Rhone basin (Switzerland as a test case for understanding anthropogenic impacts on water resources and flood risk in the Alpine area. The upper Rhone basin includes reservoirs, river diversions and irrigated areas offering the opportunity to study the interaction between climate change effects and hydraulic infrastructures. We downscale climate model realizations using a methodology that partially account for the uncertainty in climate change projections explicitly simulating stochastic variability of precipitation and air temperature. We show how climate change effects on streamflow propagate from high elevation headwater catchments to the river in the major valley. Changes in the natural hydrological regime imposed by the existing hydraulic infrastructure are likely larger than climate change signals expected by the middle of the 21th century in most of the river network. Despite a strong uncertainty induced by stochastic climate variability, we identified an elevational dependence of climate change impacts on streamflow with a severe reduction due to the missing contribution of water from ice melt at high-elevation and a dampened effect downstream. The presence of reservoirs and river diversions tends to decrease the uncertainty in future streamflow predictions that are conversely very large for highly glacierized catchments. Despite uncertainty, reduced ice cover and ice melt are likely to have significant implication for aquatic biodiversity and hydropower production. The impacts can emerge without any additional climate warming. A decrease of August-September discharge and an increase of hourly

  15. Estimating suspended sediment yield, sedimentation controls and impacts in the Mellah Catchment of Northern Algeria

    International Nuclear Information System (INIS)

    This paper is an assessment of the suspended sediment yield in the Mellah Catchment of northern Algeria. We use discharge-sediment load relationships to explore the variability of water discharge and sediment load, and to investigate the impact of geomorphic factors disturbance on erosion and sedimentation. Suspended sediment load was analyzed in the Mellah Catchment (550 squre kms ) which was controlled by a gauging station to measure discharge and sediment transport. The relations between daily mean sediment concentration and daily mean water discharge were analyzed to develop sediment rating curves. For storms with no water samples, a sediment rating curve was developed. The technique involves stratification of data into discharge-based classes, the mean of which are used to fit a rating curve according to single flow data and season to provide various rating relationships. The mean annual sediment yield during the 24 years of the study period was 562 T km -2 in the Mellah Catchment. This drainage basin had high rainfall and runoff, the erosion was high. The high sediment yield in the Mellah basin could be explained by a high percentage of sparse grassland and cultivation developed on shallow marly silty-clayey soils with steep slopes often exceeding 12%. Almost all suspended sediment loads are transported during storm events that mainly occur in the winter and spring heavy and medium downpours. The scarceness of these events leads to a very large interseasonal variability of the wadi sediment fluxes. The negative impacts of this enhanced sediment mobility are directly felt in the western part of the basin which shows many mass movements, bank and gully erosion because cultivated areas are often bared during autumnal brief flash floods and furrowed downslope during the winter season. (author)

  16. Catchment scale multi-objective flood management

    Science.gov (United States)

    Rose, Steve; Worrall, Peter; Rosolova, Zdenka; Hammond, Gene

    2010-05-01

    Rural land management is known to affect both the generation and propagation of flooding at the local scale, but there is still a general lack of good evidence that this impact is still significant at the larger catchment scale given the complexity of physical interactions and climatic variability taking place at this level. The National Trust, in partnership with the Environment Agency, are managing an innovative project on the Holnicote Estate in south west England to demonstrate the benefits of using good rural land management practices to reduce flood risk at the both the catchment and sub-catchment scales. The Holnicote Estate is owned by the National Trust and comprises about 5,000 hectares of land, from the uplands of Exmoor to the sea, incorporating most of the catchments of the river Horner and Aller Water. There are nearly 100 houses across three villages that are at risk from flooding which could potentially benefit from changes in land management practices in the surrounding catchment providing a more sustainable flood attenuation function. In addition to the contribution being made to flood risk management there are a range of other ecosystems services that will be enhanced through these targeted land management changes. Alterations in land management will create new opportunities for wildlife and habitats and help to improve the local surface water quality. Such improvements will not only create additional wildlife resources locally but also serve the landscape response to climate change effects by creating and enhancing wildlife networks within the region. Land management changes will also restore and sustain landscape heritage resources and provide opportunities for amenity, recreation and tourism. The project delivery team is working with the National Trust from source to sea across the entire Holnicote Estate, to identify and subsequently implement suitable land management techniques to manage local flood risk within the catchments. These

  17. Spatial variability in river-catchment interaction: Combining radon measurements and salt tracer experiments

    Science.gov (United States)

    Angermann, Lisa; Tecklenburg, Christina; Blume, Theresa

    2013-04-01

    Hydrological modeling is commonly based on a discharge calibration. This approach, however, is often insufficient to properly reproduce conditions that exceed the range of calibrated conditions and is therefore inadequate for predicting reactions to a changing environment. Small headwater catchments are often characterized by manifold morphological attributes (e.g. changes in river course, variable depth to bedrock...) and complex topography, resulting in potentially high spatial variability of river-catchment interactions. Such systems are often poorly represented by simple rainfall runoff models. For that reason, increasing effort is taken to investigate the functional organization of river catchments. From a river's point of view, the first questions to be solved are: How variable is river-catchment interaction in space? Where along the river do we find exfiltrating or infiltrating conditions? Which pathway did the water take before entering the stream? To investigate these questions we used an approach that combined salt tracer experiments with Radon-222 (referred to as radon) measurements. Radon is a natural occurring radionuclide that is accumulated in water traveling through saturated bedrock and mineral material. In contact with air the inert noble gas degases quickly and is thus a reliable environmental tracer for groundwater-surface water interactions. Measurements were carried out at a 650 m long tributary of the Colpach, which is part of the Attert basin in Luxembourg. In the first phase of the experiment radon was sampled every 50 m along the tributary. At the same time, salt tracer experiments were conducted over 100 m sections, providing information on discharge at the up- and downstream end of each 100 m section, absolute gain and loss along the 100 m section and travel times between all radon sampling sites. In the second phase, three sections where investigated in more detail. The chosen sections were divided according to changes of morphological

  18. Hydrological improvements for nutrient and pollutant emission modeling in large scale catchments

    Science.gov (United States)

    Höllering, S.; Ihringer, J.

    2012-04-01

    hydrological system is simulated spatially differentiated and emissions from urban and rural areas into river courses can be detected separately. In the Ruhr catchment (4.485 km2) as a right tributary of the Rhine located in the lower mountain range of North Rhine-Westphalia in Germany for the validation period 2002-2006 the hydrological model showed first satisfying results. The feasibility study in the Ruhr shows the suitability of the approach and illustrates the potentials for further developments in terms of an implementation throughout the German and contiguous watersheds. IWG, Karlsruhe Institute of Technology (KIT). 2011. http://isww.iwg.kit.edu/MoRE.php. [Online] Institute for Water and River Basin Management, Department of Aquatic Environmental Engineering, October 2011. USGS, U.S. Geological Survey. 2009. PRMS-2009, the Precipitation-Runoff Modeling System. Denver, Colorado : s.n., 2009. Bd. U.S. Geologic Survey Open File Report.

  19. Understanding Water and Solute Fluxes in Diverse Catchments

    OpenAIRE

    Godsey, Sarah

    2009-01-01

    Catchments integrate incoming hydrological and geochemical fluxes via the mixing and reaction processes occurring within their boundaries. The catchment science community still seeks realistic and internally consistent models which explain integrated catchment behavior. It is known that the amount of streamflow responds quickly to rainfall, that stream water is predominantly "old" water which has been stored for long periods within the catchment, and that streamflow chemistry varies with flow...

  20. Juvenile salmon investigations River Wenning catchment 1981-86

    OpenAIRE

    Ingersent, B.

    1987-01-01

    As part of the River Lune juvenile salmonid investigation, a number of sites on the River Wenning catchment were electrofished annually from 1981 - 1985. Particularly low Salmon parr populations were evident for much of the Wenning catchment which has caused some concern. All the Wenning catchment electrofishing results are reported in this paper and comparisons are made with designated groups of sites on the remainder of the Lune catchment. These groups of sites are: River Lune and t...

  1. Picturing and modelling catchments by representative hillslopes

    Science.gov (United States)

    Loritz, Ralf; Hassler, Sibylle; Jackisch, Conrad; Zehe, Erwin

    2016-04-01

    Hydrological modelling studies often start with a qualitative sketch of the hydrological processes of a catchment. These so-called perceptual models are often pictured as hillslopes and are generalizations displaying only the dominant and relevant processes of a catchment or hillslope. The problem with these models is that they are prone to become too much predetermined by the designer's background and experience. Moreover it is difficult to know if that picture is correct and contains enough complexity to represent the system under study. Nevertheless, because of their qualitative form, perceptual models are easy to understand and can be an excellent tool for multidisciplinary exchange between researchers with different backgrounds, helping to identify the dominant structures and processes in a catchment. In our study we explore whether a perceptual model built upon an intensive field campaign may serve as a blueprint for setting up representative hillslopes in a hydrological model to reproduce the functioning of two distinctly different catchments. We use a physically-based 2D hillslope model which has proven capable to be driven by measured soil-hydrological parameters. A key asset of our approach is that the model structure itself remains a picture of the perceptual model, which is benchmarked against a) geo-physical images of the subsurface and b) observed dynamics of discharge, distributed state variables and fluxes (soil moisture, matric potential and sap flow). Within this approach we are able to set up two behavioral model structures which allow the simulation of the most important hydrological fluxes and state variables in good accordance with available observations within the 19.4 km2 large Colpach catchment and the 4.5 km2 large Wollefsbach catchment in Luxembourg without the necessity of calibration. This corroborates, contrary to the widespread opinion, that a) lower mesoscale catchments may be modelled by representative hillslopes and b) physically

  2. BISTRIŢA ARDELEANĂ CATCHMENT AREA – COORDINATES OF STRATEGIC LAND MANAGEMENT

    OpenAIRE

    S. F. FONOGEA; V. GLIGOR; C. N. BOŢAN; I. H. PAVEL; CS. HORVATH; CRISTINA BOLOG; V. PUIU

    2014-01-01

    Bistriţa Ardeleană Catchment Area – Coordinates of Strategic Land Management. The approach of “creation and execution” / designing of this territorial cut-out of basin type, in the paradigmatic context of the durable development, is subordinate to an (almost)exhaustive investigation of the vocation and potentiality of this area in terms of geographical and spatial organization of the territory. There may be multiple reasons to justify the existence of a paper which approaches this territory i...

  3. Modelling the impact of implementing Water Sensitive Urban Design on at a catchment scale

    DEFF Research Database (Denmark)

    Locatelli, Luca; Gabriel, S.; Bockhorn, Britta;

    Stormwater management using Water Sensitive Urban Design (WSUD) is expected to be part of future drainage systems. This project aimed to develop a set of hydraulic models of the Harrestrup Å catchment (close to Copenhagen) in order to demonstrate the importance of modeling WSUDs at different scales...... infiltration is > 80% of the annual precipitation even for small soakaway volumes. A local scale (<10ha) model examined the benefit of employing soakaways and detention basins for reducing flooding. A baseline scenario was set up and the areas which must be disconnected in order to avoid flooding identified...

  4. Attributes for NHDPlus catchments (version 1.1) for the conterminous United States: Average Annual Daily Maximum Temperature, 2002

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the average monthly maximum temperature in Celsius multiplied by 100 for 2002 compiled for every catchment of NHDPlus for the conterminous United States. The source data were the Near-Real-Time High-Resolution Monthly Average Maximum/Minimum Temperature for the Conterminous United States for 2002 raster dataset produced by the Spatial Climate Analysis Service at Oregon State University. The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio

  5. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: Average Monthly Precipitation, 2002

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the average monthly precipitation in millimeters multiplied by 100 for 2002 compiled for every catchment of NHDPlus for the conterminous United States. The source data were the Near-Real-Time Monthly High-Resolution Precipitation Climate Data Set for the Conterminous United States (2002) raster dataset produced by the Spatial Climate Analysis Service at Oregon State University. The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper

  6. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: Mean Infiltration-Excess Overland Flow, 2002

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This tabular data set represents the mean value for infiltration-excess overland flow as estimated by the watershed model TOPMODEL, compiled for every catchment of NHDPlus for the conterminous United States. Infiltration-excess overland flow, expressed as a percent of total overland flow, is simulated in TOPMODEL as precipitation that exceeds the infiltration capacity of the soil and enters the stream channel. The source data set is Infiltration-Excess Overland Flow Estimated by TOPMODEL for the Conterminous United States (Wolock, 2003). The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the

  7. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: Base-Flow Index

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This tabular data set represents the mean base-flow index expressed as a percent, compiled for every catchment in NHDPlus for the conterminous United States. Base flow is the component of streamflow that can be attributed to ground-water discharge into streams. The source data set is Base-Flow Index for the Conterminous United States (Wolock, 2003). The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy River basins, contains

  8. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: Estimated Mean Annual Natural Groundwater Recharge, 2002

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the mean annual natural groundwater recharge, in millimeters, compiled for every catchment of NHDPlus for the conterminous United States. The source data set is Estimated Mean Annual Natural Ground-Water Recharge in the Conterminous United States (Wolock, 2003). The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, containing NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy River basins, contains NHDPlus Production Units 4, 5, 7 and 9. MRB4, covering the

  9. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: Average Annual Daily Minimum Temperature, 2002

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the average monthly minimum temperature in Celsius multiplied by 100 for 2002 compiled for every catchment of NHDPlus for the conterminous United States. The source data were the Near-Real-Time High-Resolution Monthly Average Maximum/Minimum Temperature for the Conterminous United States for 2002 raster dataset produced by the Spatial Climate Analysis Service at Oregon State University. The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio

  10. Annual and Seasonal Discharge Responses to Forest/Land Cover Changes and Climate Variations in Kapuas River Basin, Indonesia

    OpenAIRE

    Wahyu, Ade; Kuntoro, Arno Adi; Yamashita, Takao

    2010-01-01

    Kapuas River basin is one of the most important natural water resources in West Kalimantan, Indonesia. However, rapid increasing of forest degradation and land cover changes in the basin and climate variations has decreased the capability of the basin to provide and maintain its functions especially as a water catchment area. Examining the impact of land cover changes and climate variations is required to identify how the on-going and possible land cover and climate change may influence the a...

  11. Morphometric analysis of Suketi river basin, Himachal Himalaya, India

    Indian Academy of Sciences (India)

    Anil M Pophare; Umesh S Balpande

    2014-10-01

    Suketi river basin is located in the Mandi district of Himachal Pradesh, India. It encompasses a central inter-montane valley and surrounding mountainous terrain in the Lower Himachal Himalaya. Morphometric analysis of the Suketi river basin was carried out to study its drainage characteristics and overall groundwater resource potential. The entire Suketi river basin has been divided into five sub-basins based on the catchment areas of Suketi trunk stream and its major tributaries. Quantitative assessment of each sub-basin was carried out for its linear, areal, and relief aspects. The analysis reveals that the drainage network of the entire Suketi river basin constitutes a 7th order basin. Out of five sub-basins, Kansa khad sub-basin (KKSB), Gangli khad sub-basin (GKSB) and Ratti khad sub-basin (RKSB) are 5th order subbasins. The Dadour khad sub-basin (DKSB) is 6th order sub-basin, while Suketi trunk stream sub-basin (STSSB) is a 7th order sub-basin. The entire drainage basin area reflects late youth to early mature stage of development of the fluvial geomorphic cycle, which is dominated by rain and snow fed lower order streams. It has low stream frequency (Fs) and moderate drainage density (Dd) of 2.69 km/km2. Bifurcation ratios (Rb) of various stream orders indicate that streams up to 3rd order are surging through highly dissected mountainous terrain, which facilitates high overland flow and less recharge into the subsurface resulting in low groundwater potential in the zones of 1st, 2nd, and 3rd order streams of the Suketi river basin. The circulatory ratio (Rc) of 0.65 and elongation ratio (Re) of 0.80 show elongated nature of the Suketi river basin, while infiltration number (If) of 10.66 indicates dominance of relief features and low groundwater potential in the high altitude mountainous terrain. The asymmetry factor (Af) of Suketi river basin indicates that the palaeo-tectonic tilting, at drainage basin scale, was towards the downstream right side of the

  12. Drought characteristics and related risks in large and mesoscale tropical catchments in Latin-America and South East Asia

    Science.gov (United States)

    Nauditt, Alexandra; Ribbe, Lars; Birkel, Christian; Célleri, Rolando

    2016-04-01

    Seasonal meteorological and hydrological droughts are a recurrent phenomenon in water abundant tropical countries and are expected to become more frequent in the future. Unusual water shortage in the past months and years has severely affected societies living in the Paraiba do Sul river basin (Brazil), the Mekong, as well as in a number of basins in Central America and Vietnam among many others. Preparedness, however, is absent and site appropriate water management measures and strategies are not available. While drought related research and water management in recent years has been widely addressed in water scarce subtropical regions, the US and Europe, not much attention has been paid to drought risk in tropical catchments. Available daily or monthly precipitation and runoff time series for catchments in Brazil, Costa Rica, Ecuador, the Mekong region and Vietnam were analysed to compare historical meteorological and hydrological drought frequency (SPI/SRI). The role of tropical catchment characteristics, storage and climate variability in seasonal drought evolvement was investigated by applying the conceptual semi-distributed HBV light model to two undisturbed catchments in Central Vietnam and 18 catchments of a size of 70-5000 km² in Costa Rica. For the Mekong and the Paraíba de Sul, the hydrological module of the WEAP model was applied to undisturbed subcatchments with the same objective. To understand and separate the anthropogenic impact on drought evolvement, the abstractions (irrigation, reservoirs, water supply) and hydrological alterations were observed and quantified by applying water allocation and balance model WEAP. We conclude that such a combined model-data analysis that equally accounts for landscape related and anthropogenic impacts on the local hydrological cycle is a useful approach for drought management in tropical countries.

  13. Estimating net anthropogenic nitrogen inputs (NANI in the Lake Dianchi Basin of China

    Directory of Open Access Journals (Sweden)

    W. Gao

    2014-03-01

    Full Text Available Net anthropogenic nitrogen inputs (NANI with components of atmospheric N deposition, synthetic N fertilizer, agricultural N fixation and N in net food and feed imports from 15 catchments in Lake Dianchi Basin were determined over an 11 year period (2000–2010. The 15 catchments range in size from 44 km2 to 316 km2 with an average of 175 km2. To reduce uncertainty from scale change methodology, results from data extracting by area-weighting and land use-weighting methods were compared. Results show that methodology for extrapolating data from county scale to watersheds has a great influence on NANI computation for catchments in the Lake Dianchi Basin, and estimates of NANI between two methods have an average difference of 30% on catchments basis while a smaller difference (15% was observed on the whole Lake Dianchi Basin basis. The riverine N export has stronger linear relationship with NANI computed by land use-weighting method, which we believe is more reliable. Overall, nitrogen inputs assessed by the NANI approach for the Lake Dianchi Basin are 9900 kg N km−2 yr−1, ranging from 6600 to 28 000 kg N km−2 yr−1 among the 15 catchments. Synthetic N fertilizer is the largest component of NANI in most subwatersheds. On average, riverine flux of nitrogen in catchments of the Lake Dianchi Basin averages 83% of NANI, far higher than generally observed in North America and Europe. Saturated N sinks and limited capacity for denitrification in rivers may be responsible for this high percent of riverine N export. A negative intercept observed in the linear relationship between NANI and riverine N export suggests the influence of pollution control measures on N flux in small watershed. The NANI methodology should be applicable in small watersheds when sufficiently detailed data are available to estimate its components.

  14. Hydropedological insights when considering catchment classification

    NARCIS (Netherlands)

    Bouma, J.; Droogers, P.; Sonneveld, M.P.W.; Ritsema, C.J.; Hunink, J.E.; Immerzeel, W.W.; Kauffman, S.

    2011-01-01

    Soil classification systems are analysed to explore the potential of developing classification systems for catchments. Soil classifications are useful to create systematic order in the overwhelming quantity of different soils in the world and to extrapolate data available for a given soil type to so

  15. Hydropedological insights when considering catchment classification

    NARCIS (Netherlands)

    Bouma, J.; Droogers, P.; Sonneveld, M.P.W.; Ritsema, C.J.; Hunink, J.E.; Immerzeel, W.W.; Kauffman, S.

    2011-01-01

    Soil classification systems are analysed in relation to the functioning and characterisation of catchments. Soil classifications are useful to create systematic order in the overwhelming quantity of different soils in the world and to extrapolate data available for a given soil type to soils elsewhe

  16. Catchment management and the Great Barrier Reef.

    Science.gov (United States)

    Brodie, J; Christie, C; Devlin, M; Haynes, D; Morris, S; Ramsay, M; Waterhouse, J; Yorkston, H

    2001-01-01

    Pollution of coastal regions of the Great Barrier Reef is dominated by runoff from the adjacent catchment. Catchment land-use is dominated by beef grazing and cropping, largely sugarcane cultivation, with relatively minor urban development. Runoff of sediment, nutrients and pesticides is increasing and for nitrogen is now four times the natural amount discharged 150 years ago. Significant effects and potential threats are now evident on inshore reefs, seagrasses and marine animals. There is no effective legislation or processes in place to manage agricultural pollution. The Great Barrier Reef Marine Park Act does not provide effective jurisdiction on the catchment. Queensland legislation relies on voluntary codes and there is no assessment of the effectiveness of the codes. Integrated catchment management strategies, also voluntary, provide some positive outcomes but are of limited success. Pollutant loads are predicted to continue to increase and it is unlikely that current management regimes will prevent this. New mechanisms to prevent continued degradation of inshore ecosystems of the Great Barrier Reef World Heritage Area are urgently needed. PMID:11419129

  17. Assessment of water availability in Chindwinn catchment

    International Nuclear Information System (INIS)

    A study of water balance over Chindwinn Catchment has been carried out by using three decades of available climatological and hydrological data (i.e. from 1967). The study was based on the monthly, annual and normal values. Actual evapotranspiration (AET) computed by as well as on the using Penman (1963) as well as Hargreaves (1985) methods. Some of the reliable data of evaporation at the stations were also used to estimate actual evaporation with the pancoefficient value 0.7. The values of actual evapotranspiration estimated by Hargreaves method was lower than the values estimated by Penman, but most followed the same significant trend. The soil moisture deficiency generally occurs during November and April. A few cases of soil moisture deficiency do occur in August, September and October. However, on the overall availability of water in the catchment is quite promising. The residual resulted from the water balance estimation may be assumed as soil moisture in the catchment by neglecting some losses from the catchment. (author)

  18. Characterization of the regional variability of flood regimes within the Omo-Gibe River Basin, Ethiopia

    Science.gov (United States)

    Yared, Adanech; Demissie, Solomon S.; Sivapalan, Murugesu; Viglione, Alberto; MacAlister, Charlotte

    2014-05-01

    Hydrological variability and seasonality is one of the Ethiopia's primary water resource management challenges. Variability is most obviously manifest in endemic, devastating droughts and floods. While the level of flooding is quite often extremely high and destroys human beings and property, in many cases flooding is of vital importance because the community benefits from flood recession agriculture. This is the case of the lower Omo plain whose agriculture is based on the regularity of the inundations due to flooding of the Omo Gibe River. The big flood in 2006, which caused death for more than 300 people and 2000 cattle, poses a dilemma. Flooding must be controlled and regulated in a way that the damages are reduced as much as possible but the flooding-related benefits are not lost. To this aim, characterization and understanding of hydrological variability of the Omo Gibe River basin is fundamental. The goal of this work is to extract the maximal amount of information on the hydrological variability and specially on the flooding regime from the few data available in the region. Because most of the basin is ungauged, hydrological information is reconstructed using the data from 9 gauged catchments. A daily water balance model has been developed, calibrated and validated for 9 gauged catchments and, subsequently, the parameters have been correlated to catchment characteristics in order to establish a functional relationship that allows to apply the model to ungauged catchments. Daily streamflow has been predicted for 15 ungauged catchments, which are assumed to comprehensively represent the hydrological variability of the Omo-Gibe River Basin. Even though both northern and southern catchments are affected by a strong seasonality of precipitation, with most of the rain falling in less than 3 months, most of the northern catchments are humid, while in the southern part of the Omo-Gibe River basin, the catchments are either humid, dry sub humid, semiarid or arid. As

  19. Catchment scale afforestation for mitigating flooding

    Science.gov (United States)

    Barnes, Mhari; Quinn, Paul; Bathurst, James; Birkinshaw, Stephen

    2016-04-01

    After the 2013-14 floods in the UK there were calls to 'forest the uplands' as a solution to reducing flood risk across the nation. At present, 1 in 6 homes in Britain are at risk of flooding and current EU legislation demands a sustainable, 'nature-based solution'. However, the role of forests as a natural flood management technique remains highly controversial, due to a distinct lack of robust evidence into its effectiveness in reducing flood risk during extreme events. SHETRAN, physically-based spatially-distributed hydrological models of the Irthing catchment and Wark forest sub-catchments (northern England) have been developed in order to test the hypothesis of the effect trees have on flood magnitude. The advanced physically-based models have been designed to model scale-related responses from 1, through 10, to 100km2, a first study of the extent to which afforestation and woody debris runoff attenuation features (RAFs) may help to mitigate floods at the full catchment scale (100-1000 km2) and on a national basis. Furthermore, there is a need to analyse the extent to which land management practices, and the installation of nature-based RAFs, such as woody debris dams, in headwater catchments can attenuate flood-wave movement, and potentially reduce downstream flood risk. The impacts of riparian planting and the benefits of adding large woody debris of several designs and on differing sizes of channels has also been simulated using advanced hydrodynamic (HiPIMS) and hydrological modelling (SHETRAN). With the aim of determining the effect forestry may have on flood frequency, 1000 years of generated rainfall data representative of current conditions has been used to determine the difference between current land-cover, different distributions of forest cover and the defining scenarios - complete forest removal and complete afforestation of the catchment. The simulations show the percentage of forestry required to have a significant impact on mitigating

  20. Catchment features controlling nitrogen dynamics in running waters above the tree line (Central Italian Alps

    Directory of Open Access Journals (Sweden)

    R. Balestrini

    2012-09-01

    Full Text Available The study of nitrogen cycling in mountain areas has a long tradition, both to better understand and describe ecosystem functioning and to quantify the long-distance effect of human activities on remote environments. Nonetheless, especially in Europe, very few studies paid attention on catchment features controlling nitrogen dynamics above the tree line, with focus on running waters. In this study, relationships between some water chemistry descriptors, including nitrogen species and dissolved organic carbon (DOC, and catchment characteristics were evaluated for a range of sites located above the tree line (1950–2650 m a.s.l. at Val Masino, in the Central Italian Alps. Land cover categories as well as elevation and slope were assessed at each site. Water samples were collected during the 2007 and 2008 snow free periods, with a nearly monthly frequency. Differently to dissolved organic nitrogen, nitrate concentration in running waters showed a spatial pattern strictly connected to the fractional extension of tundra and talus in each basin. Exponential models significantly described the relationships between maximum NO3-N and the fraction of vegetated soil cover (negative relation and talus (positive relation, explaining almost 90% of nitrate variation in running waters. Similarly to nitrate, but with an opposite behavior, DOC was positively correlated with vegetated soil cover and negatively correlated with talus. Therefore, land cover can be considered one of the most important factors affecting water quality in high elevation catchments, with a contrasting effect on N and C pools.

  1. Catchment features controlling nitrogen dynamics in running waters above the tree line (central Italian Alps

    Directory of Open Access Journals (Sweden)

    R. Balestrini

    2013-03-01

    Full Text Available The study of nitrogen cycling in mountain areas has a long tradition, as it was applied to better understand and describe ecosystem functioning, as well as to quantify long-distance effects of human activities on remote environments. Nonetheless, very few studies, especially in Europe, have considered catchment features controlling nitrogen dynamics above the tree line with focus on running waters. In this study, relationships between some water chemistry descriptors – including nitrogen species and dissolved organic carbon (DOC – and catchment characteristics were evaluated for a range of sites located above the tree line (1950–2650 m a.s.l. at Val Masino, in the central Italian Alps. Land cover categories as well as elevation and slope were assessed at each site. Water samples were collected during the 2007 and 2008 snow free periods, with a nearly monthly frequency. In contrast to dissolved organic nitrogen, nitrate concentrations in running waters showed a spatial pattern strictly connected to the fractional extension of tundra and talus in each basin. Exponential models significantly described the relationships between maximum NO3 and the fraction of vegetated soil cover (negative relation and talus (positive relation, explaining almost 90% of nitrate variation in running waters. Similarly to nitrate but with an opposite behavior, DOC was positively correlated with vegetated soil cover and negatively correlated with talus. Therefore, land cover can be considered one of the most important factors affecting water quality in high-elevation catchments with contrasting effects on N and C pools.

  2. Implementation of E.U. Water Framework Directive: source assessment of metallic substances at catchment levels.

    Science.gov (United States)

    Chon, Ho-Sik; Ohandja, Dieudonne-Guy; Voulvoulis, Nikolaos

    2010-01-01

    The E.U. Water Framework Directive (WFD) aims to prevent deterioration of water quality and to phase out or reduce the concentrations of priority substances at catchment levels. It requires changes in water management from a local scale to a river basin scale, and establishes Environmental Quality Standards (EQS) as a guideline for the chemical status of receiving waters. According to the Directive, the standard and the scope of the investigation for water management are more stringent and expanded than in the past, and this change also needs to be applied to restoring the level of metals in water bodies. The aim of this study was to identify anthropogenic emission sources of metallic substances at catchment levels. Potential sources providing substantial amounts of such substances in receiving waters included stormwater, industrial effluents, treated effluents, agricultural drainage, sediments, mining drainage and landfill leachates. Metallic substances have more emission sources than other dangerous substances at catchment levels. Therefore, source assessment for these substances is required to be considered more significantly to restore their chemical status in the context of the WFD. To improve source assessment quality, research on the role of societal and environmental parameters and contribution of each source to the chemical distribution in receiving waters need to be carried out. PMID:20081997

  3. Paradigm Shift in Transboundary Water Management Policy: Linking Water Environment Energy and Food (weef) to Catchment Hydropolitics - Needs, Scope and Benefits

    Science.gov (United States)

    RAI, S.; Wolf, A.; Sharma, N.; Tiwari, H.

    2015-12-01

    The incessant use of water due to rapid growth of population, enhanced agricultural and industrial activities, degraded environment and ecology will in the coming decades constrain the socioeconomic development of humans. To add on to the precarious situation, political boundaries rarely embrace hydrological boundaries of lakes, rivers, aquifers etc. Hydropolitics relate to the ability of geopolitical institutions to manage shared water resources in a politically sustainable manner, i.e., without tensions or conflict between political entities. Riparian hydropolitics caters to differing objectives, needs and requirements of states making it difficult to administer the catchment. The diverse riparian objectives can be merged to form a holistic catchment objective of sustainable water resources development and management. It can be proposed to make a paradigm shift in the present-day transboundary water policy from riparian hydropolitics (in which the focal point of water resources use is hinged on state's need) to catchment hydropolitics (in which the interest of the basin inhabitants are accorded primacy holistically over state interests) and specifically wherein the water, environment, energy and food (WEEF) demands of the catchment are a priority and not of the states in particular. The demands of the basin pertaining to water, food and energy have to be fulfilled, keeping the environment and ecology healthy in a cooperative political framework; the need for which is overwhelming. In the present scenario, the policy for water resources development of a basin is segmented into independent uncoordinated parts controlled by various riparians; whereas in catchment hydropolitics the whole basin should be considered as a unit. The riparians should compromise a part of national interest and work in collaboration on a joint objective which works on the principle of the whole as against the part. Catchment hydropolitics may find greater interest in the more than 250

  4. Attributes for NHDPlus Catchments (Version 1.1)for the Conterminous United States: Contact Time, 2002

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the average contact time, in units of days, compiled for every catchment of NHDPlus for the conterminous United States. Contact time, as described in Wolock and others (1989), is the baseflow residence time in the subsurface. The source data set was the U.S. Geological Survey's (USGS) 1-kilometer grid for the conterminous United States (D.M. Wolock, U.S. Geological Survey, written commun., 2008). The grid was created using a method described by Wolock and others (1997a; see equation 3). In the source data set, the contact time was estimated from 1-kilometer resolution elevation data (Verdin and Greenlee, 1996 ) and STATSGO soil characteristics (Wolock, 1997b). The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs

  5. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: NLCD 2001 Imperviousness

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy River basins, contains NHDPlus Production Units 4, 5, 7 and 9. MRB4, covering the Missouri River basins, contains NHDPlus Production Units 10-lower and 10-upper. MRB5, covering the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf River basins, contains NHDPlus Production Units 8, 11 and 12. MRB6, covering the Rio Grande, Colorado and Great Basin River basins, contains NHDPlus Production Units 13, 14, 15 and 16. MRB7, covering the Pacific Northwest River basins, contains NHDPlus Production Unit 17. MRB8, covering California River basins, contains NHDPlus Production Unit 18.

  6. A general protocol for restoration of entire river catchments

    Energy Technology Data Exchange (ETDEWEB)

    Stanford, J.A.; Frissell, C.A. [Univ. of Montana, Polson, MT (United States). Flathead Lake Biological Station; Ward, J.V. [EAWAG/ETH, Dubendorf (Switzerland). Dept. of Limnology; Liss, W.J. [Oregon State Univ., Corvallis, OR (United States). Dept. of Fisheries and Wildlife; Coutant, C.C. [Oak Ridge National Lab., TN (United States); Williams, R.N.; Lichatowich, J.A.

    1996-05-28

    Large catchment basins may be viewed as ecosystems with interactive natural and cultural attributes. Stream regulation severs ecological connectivity between channels and flood plains by reducing the range of natural flow and temperature variation, reduces the capacity of the ecosystem to sustain native biodiversity and bioproduction and promotes proliferation of non-native biota. However, regulated rivers regain normative attributes, which promote recovery of native biota, as distance from the dam increases and in relation to the mode of regulation. Therefore, reregulation of flow and temperature to normative pattern, coupled with elimination of pollutants and constrainment of nonnative biota, can naturally restore damaged habitats from headwaters to mouth. The expectation is rapid recovery of depressed populations of native species. The protocol requires: restoration of seasonal temperature patterns; restoration of peak flows needed to reconnect and periodically reconfigure channel and floodplain habitats; stabilization of base flows to revitalize the shallow water habitats; maximization of dam passage to allow restoration of metapopulation structure; change in the management belief system to rely on natural habitat restoration as opposed to artificial propagation, installation of artificial instream structures (river engineering) and artificial food web control; and, practice of adaptive ecosystem management.

  7. The contribution of sea-level rise to flooding in large river catchments

    Science.gov (United States)

    Thiele-Eich, I.; Hopson, T. M.; Gilleland, E.; Lamarque, J.; Hu, A.; Simmer, C.

    2012-12-01

    Climate change is expected to both impact sea level rise as well as flooding. Our study focuses on the combined effect of climate change on upper catchment precipitation as well as on sea-level rise at the river mouths and the impact this will have on river flooding both at the coast and further upstream. We concentrate on the eight catchments of the Amazonas, Congo, Orinoco, Ganges/Brahmaputra/Meghna, Mississippi, St. Lawrence, Danube and Niger rivers. To assess the impact of climate change, upper catchment precipitation as well as monthly mean thermosteric sea-level rise at the river mouth outflow are taken from the four CCSM4 1° 20th Century ensemble members as well as from six CCSM4 1° ensemble members for the RCP scenarios RCP8.5, 6.0, 4.5 and 2.6. Continuous daily time series for average catchment precipitation and discharge are available for each of the catchments. To arrive at a future discharge time series, we used these observations to develop a simple statistical hydrological model which can be applied to the modelled future upper catchment precipitation values. The analysis of this surrogate discharge time series alone already yields significant changes in flood return levels as well as flood duration. Using the geometry of the river channel, the backwater effect of sea-level rise is incorporated in our analysis of both flood frequencies and magnitudes by calculating the effective additional discharge due to the increase in water level at the river mouth outflow, as well as its tapering impact upstream. By combining these effects, our results focus on the merged impact of changes in extreme precipitation with increases in river height due to sea-level rise at the river mouths. Judging from our preliminary results, the increase in effective discharge due to sea-level rise cannot be neglected when discussing late 21st century flooding in the respective river basins. In particular, we find that especially in countries with low elevation gradient, flood

  8. Spatial variability of herbicide mobilisation and transport at catchment scale: insights from a field experiment

    Directory of Open Access Journals (Sweden)

    T. Doppler

    2012-02-01

    Full Text Available During rain events, herbicides can be transported from their point of application to surface waters where they may harm aquatic organisms. Since the spatial pattern of mobilisation and transport is heterogeneous, the contributions of different fields to the herbicide load in the stream may differ considerably within one catchment. Therefore, the prediction of contributing areas could help to target mitigation measures efficiently to those locations where they reduce herbicide pollution the most.

    Such spatial predictions require sufficient insight into the underlying transport processes. To improve the understanding of the process chain of herbicide mobilisation on the field and the subsequent transport through the catchment to the stream, we performed a controlled herbicide application on corn fields in a small agricultural catchment (ca. 1 km2 with intensive crop production in the Swiss Plateau. For two months after application in 2009, water samples were taken at different locations in the catchment (overland flow, tile drains and open channel with a high temporal resolution during rain events. We also analysed soil samples from the experimental fields and measured discharge, groundwater level, soil moisture and the occurrence of overland flow at several locations. Several rain events with varying intensities and magnitudes occurred during the study period. Overland flow and erosion were frequently observed in the entire catchment. Infiltration excess and saturation excess overland flow were both observed. However, the main herbicide loss event was dominated by infiltration excess. This is in contrast to earlier studies in the Swiss Plateau, demonstrating that saturation excess overland flow was the dominant process.

    Despite the frequent and wide-spread occurrence of overland flow, most of this water did not directly reach the channel. It mostly got retained in small sinks in the catchment. From there, it reached

  9. A Project for Developing an Original Methodology Intended for Determination of the River Basin/Sub-Basin Boundaries and Codes in Western Mediterranean Basin in Turkey with Perspective of European Union Directives

    Science.gov (United States)

    Gökgöz, Türkay; Ozulu, Murat; Erdoǧan, Mustafa; Seyrek, Kemal

    2016-04-01

    From the view of integrated river basin management, basin/sub-basin boundaries should be determined and encoded systematically with sufficient accuracy and precision. Today basin/sub-basin boundaries are mostly derived from digital elevation models (DEM) in geographic information systems (GIS). The accuracy and precision of the basin/sub-basin boundaries depend primarily on the accuracy and resolution of the DEMs. In this regard, in Turkey, a survey was made for the first time within the scope of this project to identify current situation, problems and needs in General Directorates of State Hydraulic Works, Water Management, Forestry, Meteorology, Combating Desertification and Erosion, which are the major institutions with responsibility and authority. Another factor that determines the accuracy and precision of basin/sub-basin boundaries is the flow accumulation threshold value to be determined at a certain stage according to a specific methodology in deriving the basin/sub-basin boundaries from DEM. Generally, in Turkey, either the default value given by GIS tool is used directly without any geomorphological, hydrological and cartographic bases or it is determined by trial and error. Although there is a system of catchments and rivers network at 1:250,000 scale and a proper method has already been developed on systematic coding of the basin by the General Directorate of State Hydraulic Works, it is stated that a new system of catchments, rivers network and coding at larger scale (i.e. 1:25,000) is needed. In short, the basin/sub-basin boundaries and codes are not available currently at the required accuracy and precision for the fulfilment of the obligations described in European Union (EU) Water Framework Directive (WFD). In this case, it is clear that there is not yet any methodology to obtain such products. However, a series of projects should be completed such that the basin/sub-basin boundaries and codes are the fundamental data infrastructure. This task

  10. Development of catchment research, with particular attention to Plynlimon and its forerunner, the East African catchments

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available Dr J.S.G. McCulloch was deeply involved in the establishment of research catchments in East Africa and subsequently in the UK to investigate the hydrological consequences of changes in land use. Comparison of these studies provides an insight into how influential his inputs and direction have been in the progressive development of the philosophy, the instrumentation and the analytical techniques now employed in catchment research. There were great contrasts in the environments: tropical highland (high radiation, intense rainfall vs. temperate maritime (low radiation and frontal storms, contrasting soils and vegetation types, as well as the differing social and economic pressures in developing and developed nations. Nevertheless, the underlying scientific philosophy was common to both, although techniques had to be modified according to local conditions. As specialised instrumentation and analytical techniques were developed for the UK catchments many were also integrated into the East African studies. Many lessons were learned in the course of these studies and from the experiences of other studies around the world. Overall, a rigorous scientific approach was developed with widespread applicability. Beyond the basics of catchment selection and the quantification of the main components of the catchment water balance, this involved initiating parallel process studies to provide information on specific aspects of catchment behaviour. This information could then form the basis for models capable of extrapolation from the observed time series to other periods/hydrological events and, ultimately, the capability of predicting the consequences of changes in catchment land management to other areas in a range of climates.

  11. Impact of land use changes on connectivity in a rural catchment with mild topography

    Science.gov (United States)

    Langhammer, Jakub; Ghaffari, Golaleh

    2016-04-01

    Concept of sediment connectivity and quantitative assessment of its spatial distribution became important tool for analysis of spatial connectivity of sediment transport processes in basins. Most of the first connectivity studies is focused on montane basins with high rates of erosion originating in steep slopes in headwater areas. However, less attention is paid to the mild landscapes in highland and lowland landscape, with often high connectivity. It applies to the rural areas where the sediment transport and erosion control are of key importance. Assessment of connectivity and its control in such environment thus can contribute to the efficient and sustainable landscape management. In our study we have tested applicability of the concept of index of sediment connectivity (IC) in mid-latitude rural catchment with mild topography and extensive share of arable land. The aim of the study was (i) to test the GIS-based IC calculation in specific topographic conditions, (ii) to assess the effects of land use changes on the sediment connectivity and (iii) to identify the landscape features affecting connection between hillslopes and stream channels. The study area - Loucka River Basin, Czech Republic with area of 386 sq km is located in highland landscape with 60% share of arable land. The basin study area has a reverse pattern of topography compared to the typical montane catchments - the extensive headwater areas, used for agriculture, are flat and are drained into steep valleys in downstream. The basin is equipped with long-term monitoring of suspended sediment transport. We have used the high resolution 5 meter DEM derived from aerial LiDAR scanning as a base for analysis of topographic controls of sediment connectivity and for calculation of connectivity topographic index. The index of connectivity was calculated in a multitemporal scale of two decades since 1990 to analyze the the changes of sediment connectivity and its spatial distribution in response to the

  12. Sediment yield model implementation based on check dam infill stratigraphy in a semiarid Mediterranean catchment

    Directory of Open Access Journals (Sweden)

    G. Bussi

    2013-08-01

    Full Text Available Soil loss and sediment transport in Mediterranean areas are driven by complex non-linear processes which have been only partially understood. Distributed models can be very helpful tools for understanding the catchment-scale phenomena which lead to soil erosion and sediment transport. In this study, a modelling approach is proposed to reproduce and evaluate erosion and sediment yield processes in a Mediterranean catchment (Rambla del Poyo, Valencia, Spain. Due to the lack of sediment transport records for model calibration and validation, a detailed description of the alluvial stratigraphy infilling a check dam that drains a 12.9 km2 sub-catchment was used as indirect information of sediment yield data. These dam infill sediments showed evidences of at least 15 depositional events (floods over the time period 1990–2009. The TETIS model, a distributed conceptual hydrological and sediment model, was coupled to the Sediment Trap Efficiency for Small Ponds (STEP model for reproducing reservoir retention, and it was calibrated and validated using the sedimentation volume estimated for the depositional units associated with discrete runoff events. The results show relatively low net erosion rates compared to other Mediterranean catchments (0.136 Mg ha−1 yr−1, probably due to the extensive outcrops of limestone bedrock, thin soils and rather homogeneous vegetation cover. The simulated sediment production and transport rates offer model satisfactory results, further supported by in-site palaeohydrological evidences and spatial validation using additional check dams, showing the great potential of the presented data assimilation methodology for the quantitative analysis of sediment dynamics in ungauged Mediterranean basins.

  13. Forest management effects on snow, runoff and evapotranspiration in Sierra Nevada mixed-conifer headwater catchments

    Science.gov (United States)

    Ray, R. L.; Saksa, P. C.; Bales, R. C.; Conklin, M. H.

    2012-12-01

    We used intensive field measurements and data-intensive hydro-ecological modeling to investigate the impact of forest vegetation management on the sensitivity of snow accumulation, evapotranspiration and discharge at seven headwater catchments in the Sierra Nevada. Catchments are located in dense mixed-conifer forest, at elevations of 1500 - 2100 m, and receive a mix of rain and snow precipitation. Management scenarios for reducing forest density by uniform thinning and forest clearings were implemented in the Regional Hydro-ecological Simulation System (RHESSys). Results obtained using inherent model equations to separate total precipitation into snow and rain underestimated snow water content in some of the catchments, requiring manual input of snow and rain for accurate simulations. Modeling precipitation phase accurately was critical for the current forest condition, as the change in vegetation has differing effects on rain, snow and snowmelt. Results using RHESSys show that light, uniform thinning alone (<20% canopy) may not be enough to change water yield significantly, but this threshold of canopy reduction is lowered by creating gaps in the forest alone or in combination with uniform thinning, and has potential to measurably increase water yield beyond background variation. Clarifying these specific impacts of forest vegetation on snow processes and water yield is essential for simulating forest management in the Sierra Nevada and it shows the forest structure has significant influence on the catchment water balance. However, modifying forest canopy density and canopy cover to calculate average levels of snow water equivalent at a basin-scale may not be detailed enough to incorporate all the complex forest structure effects on snow processes in mountain watersheds.

  14. Inverse distributed hydrological modelling of Alpine catchments

    Directory of Open Access Journals (Sweden)

    H. Kunstmann

    2006-01-01

    Full Text Available Even in physically based distributed hydrological models, various remaining parameters must be estimated for each sub-catchment. This can involve tremendous effort, especially when the number of sub-catchments is large and the applied hydrological model is computationally expensive. Automatic parameter estimation tools can significantly facilitate the calibration process. Hence, we combined the nonlinear parameter estimation tool PEST with the distributed hydrological model WaSiM. PEST is based on the Gauss-Marquardt-Levenberg method, a gradient-based nonlinear parameter estimation algorithm. WaSiM is a fully distributed hydrological model using physically based algorithms for most of the process descriptions. WaSiM was applied to the alpine/prealpine Ammer River catchment (southern Germany, 710 km2 in a 100×100 m2 horizontal resolution. The catchment is heterogeneous in terms of geology, pedology and land use and shows a complex orography (the difference of elevation is around 1600 m. Using the developed PEST-WaSiM interface, the hydrological model was calibrated by comparing simulated and observed runoff at eight gauges for the hydrologic year 1997 and validated for the hydrologic year 1993. For each sub-catchment four parameters had to be calibrated: the recession constants of direct runoff and interflow, the drainage density, and the hydraulic conductivity of the uppermost aquifer. Additionally, five snowmelt specific parameters were adjusted for the entire catchment. Altogether, 37 parameters had to be calibrated. Additional a priori information (e.g. from flood hydrograph analysis narrowed the parameter space of the solutions and improved the non-uniqueness of the fitted values. A reasonable quality of fit was achieved. Discrepancies between modelled and observed runoff were also due to the small number of meteorological stations and corresponding interpolation artefacts in the orographically complex terrain. Application of a 2

  15. Inverse distributed hydrological modelling of alpine catchments

    Directory of Open Access Journals (Sweden)

    H. Kunstmann

    2005-12-01

    Full Text Available Even in physically based distributed hydrological models, various remaining parameters must be estimated for each sub-catchment. This can involve tremendous effort, especially when the number of sub-catchments is large and the applied hydrological model is computationally expensive. Automatic parameter estimation tools can significantly facilitate the calibration process. Hence, we combined the nonlinear parameter estimation tool PEST with the distributed hydrological model WaSiM. PEST is based on the Gauss-Marquardt-Levenberg method, a gradient-based nonlinear parameter estimation algorithm. WaSiM is a fully distributed hydrological model using physically based algorithms for most of the process descriptions.

    WaSiM was applied to the alpine/prealpine Ammer River catchment (southern Germany, 710 km2 in a 100×100 m2 horizontal resolution. The catchment is heterogeneous in terms of geology, pedology and land use and shows a complex orography (the difference of elevation is around 1600 m. Using the developed PEST-WaSiM interface, the hydrological model was calibrated by comparing simulated and observed runoff at eight gauges for the hydrologic year 1997 and validated for the hydrologic year 1993. For each sub-catchment four parameters had to be calibrated: the recession constants of direct runoff and interflow, the drainage density, and the hydraulic conductivity of the uppermost aquifer. Additionally, five snowmelt specific parameters were adjusted for the entire catchment. Altogether, 37 parameters had to be calibrated. Additional a priori information (e.g. from flood hydrograph analysis narrowed the parameter space of the solutions and improved the non-uniqueness of the fitted values. A reasonable quality of fit was achieved. Discrepancies between modelled and observed runoff were also due to the small number of meteorological stations and corresponding interpolation artefacts in the orographically complex

  16. Tritium balance modeling in a macroscale catchment

    International Nuclear Information System (INIS)

    Full text: The Institute of Hydrology at the Freiburg University (IHF) is working in cooperation with the German Federal Institute of Hydrology (BfG) on a project implementing tritium data into modeling concepts of large river systems. Tritium concentrations that are measured in precipitation (Global Network of Isotopes in Precipitation - GNIP) and discharge (BfG - HYDABA data base) are combined with information on water balance components on monthly basis over a period of 50 years. In a first step the Fulda and Werra catchments (6.890 km2 and 5.410 km2) in Germany were used to test the model approach, to study residence times, groundwater storage behaviour and water balance components. Environmental tritium in precipitation that was mainly introduced into the water cycle by nuclear weapon tests in the 60s is the source of tritium input in this catchments. Precipitation and potential evapotranspiration were calculated from the German Weather Authority (DWD). The TRIBIL software was developed to process a large amount of data sets. It allows to consider tritium input from precipitation, nuclear power plants and channel systems. Evapotranspiration from land and water surface as well as snow cover are considered for calculations of infiltrating water. Beneath a direct runoff component the amount of infiltrating water is distinguished into fast and slow groundwater reservoirs were each consists of a mobile and immobile fraction. The amount of tritium stored in these groundwater fractions is calculated using discharge recession curve analyses. An outline of the model structure as well as results for the river systems Fulda and Werra will be presented. A comparison of measured and modeled tritium concentrations in discharge showed considerable fits. Modeling efficiencies are around 0.8. The results allow an interpretation of storage volumes and residence times of the supposed groundwater reservoirs. Because there is no influence through nuclear power plants, tritium

  17. Establishing a connection between hydrologic model parameters and physical catchment signatures for improved hierarchical Bayesian modeling in ungauged catchments

    Science.gov (United States)

    Marshall, L. A.; Weber, K.; Smith, T. J.; Greenwood, M. C.; Sharma, A.

    2012-12-01

    In an effort to improve hydrologic analysis in areas with limited data, hydrologists often seek to link catchments where little to no data collection occurs to catchments that are gauged. Various metrics and methods have been proposed to identify such relationships, in the hope that "surrogate" catchments might provide information for those catchments that are hydrologically similar. In this study we present a statistical analysis of over 150 catchments located in southeast Australia to examine the relationship between a hydrological model and certain catchment metrics. A conceptual rainfall-runoff model is optimized for each of the catchments and hierarchical clustering is performed to link catchments based on their calibrated model parameters. Clustering has been used in recent hydrologic studies but catchments are often clustered based on physical characteristics alone. Usually there is little evidence to suggest that such "surrogate" data approaches provide sufficiently similar model predictions. Beginning with model parameters and working backwards, we hope to establish if there is a relationship between the model parameters and physical characteristics for improved model predictions in the ungauged catchment. To analyze relationships, permutational multivariate analysis of variance tests are used that suggest which hydrologic metrics are most appropriate for discriminating between calibrated catchment clusters. Additional analysis is performed to determine which cluster pairs show significant differences for various metrics. We further examine the extent to which these results may be insightful for a hierarchical Bayesian modeling approach that is aimed at generating model predictions at an ungauged site. The method, known as Bayes Empirical Bayes (BEB) works to pool information from similar catchments to generate informed probability distributions for each model parameter at a data-limited catchment of interest. We demonstrate the effect of selecting

  18. Vinna Basin

    Czech Academy of Sciences Publication Activity Database

    Honěk, J.; Franců, J.; Mikuláš, Radek; Pešek, J.; Sýkorová, Ivana; Tomanová-Petrová, P.

    Prague: Czech Geological Survey, 2014, s. 223-241 ISBN 978-80-7075-862-5 R&D Projects: GA ČR GA105/06/0653 Institutional support: RVO:67985891 ; RVO:67985831 Keywords : Tertiary basins * Czech Republic * Cenomanian and Tertiary lignite * geology * stratigraphy Subject RIV: DB - Geology ; Mineralogy

  19. Estimation of predictive hydrologic uncertainty using quantile regression and UNEEC methods and their comparison on contrasting catchments

    Science.gov (United States)

    Dogulu, N.; López López, P.; Solomatine, D. P.; Weerts, A. H.; Shrestha, D. L.

    2014-09-01

    In operational hydrology, estimation of predictive uncertainty of hydrological models used for flood modelling is essential for risk based decision making for flood warning and emergency management. In the literature, there exists a variety of methods analyzing and predicting uncertainty. However, case studies comparing performance of these methods, most particularly predictive uncertainty methods, are limited. This paper focuses on two predictive uncertainty methods that differ in their methodological complexity: quantile regression (QR) and UNcertainty Estimation based on local Errors and Clustering (UNEEC), aiming at identifying possible advantages and disadvantages of these methods (both estimating residual uncertainty) based on their comparative performance. We test these two methods on several catchments (from UK) that vary in its hydrological characteristics and models. Special attention is given to the errors for high flow/water level conditions. Furthermore, normality of model residuals is discussed in view of clustering approach employed within the framework of UNEEC method. It is found that basin lag time and forecast lead time have great impact on quantification of uncertainty (in the form of two quantiles) and achievement of normality in model residuals' distribution. In general, uncertainty analysis results from different case studies indicate that both methods give similar results. However, it is also shown that UNEEC method provides better performance than QR for small catchments with changing hydrological dynamics, i.e. rapid response catchments. We recommend that more case studies of catchments from regions of distinct hydrologic behaviour, with diverse climatic conditions, and having various hydrological features be tested.

  20. Source identification of fine-grained suspended sediment in the Kharaa River basin, northern Mongolia

    International Nuclear Information System (INIS)

    Fine sediment inputs into river systems can be a major source of nutrients and heavy metals and have a strong impact on water quality and ecosystem functions of rivers and lakes, including those in semiarid regions. However, little is known to date about the spatial distribution of sediment sources in most large scale river basins in Central Asia. Accordingly, a sediment source fingerprinting technique was used to assess the spatial sources of fine-grained (< 10 μm) sediment in the 15 000 km2 Kharaa River basin in northern Mongolia. Variation in geochemical composition (e.g. in Ti, Sn, Mo, Mn, As, Sr, B, U, Ca and Sb) was used for sediment source discrimination with geochemical composite fingerprints based on Genetic Algorithm (GA)-driven Discriminant Function Analysis, the Kruskal–Wallis H-test and Principal Component Analysis. All composite fingerprints yielded a satisfactory GOF (> 0.97) and were subsequently used for numerical mass balance modelling with uncertainty analysis. The contributions of the individual sub-catchment spatial sediment sources varied from 6.4% (the headwater sub-catchment of Sugnugur Gol) to 36.2% (the Kharaa II sub-catchment in the middle reaches of the study basin), generally showing higher contributions from the sub-catchments in the middle, rather than the upstream, portions of the study area. The importance of river bank erosion is shown to increase from upstream to midstream tributaries. The source tracing procedure provides results in reasonable accordance with previous findings in the study region and demonstrates the applicability and associated uncertainties of the approach for fine-grained sediment source investigation in large scale semi-arid catchments. - Highlights: • Applied statistical approach for selecting composite fingerprints in Mongolia. • Geochemical fingerprinting for the definition of source areas in semiarid catchment. • Test of applicability of sediment sourcing in large scale semi-arid catchments.

  1. Source identification of fine-grained suspended sediment in the Kharaa River basin, northern Mongolia

    Energy Technology Data Exchange (ETDEWEB)

    Theuring, Philipp [Department of Aquatic Ecosystem Analysis and Management — ASAM, Helmholtz Centre for Environmental Research — UFZ, Brückstrasse 3a, D-39114 Magdeburg (Germany); Collins, Adrian L. [Sustainable Soils and Grassland Systems Department, Rothamsted Research, North Wyke, Okehampton, Devon EX20 2SB (United Kingdom); Rode, Michael [Department of Aquatic Ecosystem Analysis and Management — ASAM, Helmholtz Centre for Environmental Research — UFZ, Brückstrasse 3a, D-39114 Magdeburg (Germany)

    2015-09-01

    Fine sediment inputs into river systems can be a major source of nutrients and heavy metals and have a strong impact on water quality and ecosystem functions of rivers and lakes, including those in semiarid regions. However, little is known to date about the spatial distribution of sediment sources in most large scale river basins in Central Asia. Accordingly, a sediment source fingerprinting technique was used to assess the spatial sources of fine-grained (< 10 μm) sediment in the 15 000 km{sup 2} Kharaa River basin in northern Mongolia. Variation in geochemical composition (e.g. in Ti, Sn, Mo, Mn, As, Sr, B, U, Ca and Sb) was used for sediment source discrimination with geochemical composite fingerprints based on Genetic Algorithm (GA)-driven Discriminant Function Analysis, the Kruskal–Wallis H-test and Principal Component Analysis. All composite fingerprints yielded a satisfactory GOF (> 0.97) and were subsequently used for numerical mass balance modelling with uncertainty analysis. The contributions of the individual sub-catchment spatial sediment sources varied from 6.4% (the headwater sub-catchment of Sugnugur Gol) to 36.2% (the Kharaa II sub-catchment in the middle reaches of the study basin), generally showing higher contributions from the sub-catchments in the middle, rather than the upstream, portions of the study area. The importance of river bank erosion is shown to increase from upstream to midstream tributaries. The source tracing procedure provides results in reasonable accordance with previous findings in the study region and demonstrates the applicability and associated uncertainties of the approach for fine-grained sediment source investigation in large scale semi-arid catchments. - Highlights: • Applied statistical approach for selecting composite fingerprints in Mongolia. • Geochemical fingerprinting for the definition of source areas in semiarid catchment. • Test of applicability of sediment sourcing in large scale semi-arid catchments

  2. Catchment Engineering: A New Paradigm in Water Management

    Science.gov (United States)

    Quinn, P. F.; Burke, S.; O'Donnell, G. M.; Wilkinson, M.; Jonczyk, J.; Barber, N.; Nicholson, A.; Proactive Team

    2011-12-01

    Recent catchment initiatives have highlighted the need for new holistic approaches to sustainable water management. Here, a catchment engineering approach seeks to describe catchment 'function' (or role) as the principal driver for evaluating how it should be managed in the future. Catchment engineering does not seek to re-establish a natural system but seeks to work with natural processes in order to engineer landscapes so that multiple benefits accrue. This approach involves quantifying and assessing catchment change and impacts but most importantly suggests an urgent and proactive agenda for future planning. In particular, an interventionist approach to managing hydrological flow pathways across scale is proposed. It is already accepted that future management will require a range of scientific expertise and full engagement with stakeholders, namely the general public and policy makers. This inclusive concept under a catchment engineering agenda forces any consortia to commit to actively changing and perturbing the catchment system and thus learn, in situ, how to manage the environment for collective benefits. The shared cost, the design, the implementation, the evaluation and any subsequent modifications should involve all relevant parties in the consortia. This joint ownership of a 'hands on' interventionist agenda to catchment change is at the core of catchment engineering. In this paper we show a range of catchment engineering projects from the UK that have addressed multi-disciplinary approaches to flooding, pollution and ecosystem management whilst maintaining economic food production. Local scale demonstration activities, led by local champions, have proven to be an effective means of encouraging wider uptake. Catchment engineering is a concept that relies on all relevant parties within a catchment to take responsibility for the water quantity and quality that arises from the catchment. Further, any holistic solution requires a bottom up, problem solving

  3. Collaborative Catchment-Scale Water Quality Management using Integrated Wireless Sensor Networks

    Science.gov (United States)

    Zia, Huma; Harris, Nick; Merrett, Geoff

    2013-04-01

    collaborative information sharing can have a direct influence on agricultural practice. We apply a nutrient management scheme to a model of an example catchment with several individual networks. The networks are able to correlate catchment events to events within their zone of influence, allowing them to adapt their monitoring and control strategy in light of wider changes across the catchment. Results indicate that this can lead to significant reductions in nutrient losses (up to 50%) and better reutilization of nutrients amongst farms, having a positive impact on catchment scale water quality and fertilizer costs. 1. EC, E.C., Directive 2000/60/EC establishing a framework for Community action in the field of water policy, 2000. 2. Rivers, M., K. Smettem, and P. Davies. Estimating future scenarios for farm-watershed nutrient fluxes using dynamic simulation modelling-Can on-farm BMPs really do the job at the watershed scale? in Proc.29th Int.Conf System Dynamics Society, 2011. 2010. Washington 3. Liu, C., et al., On-farm evaluation of winter wheat yield response to residual soil nitrate-N in North China Plain. Agronomy Journal, 2008. 100(6): p. 1527-1534. 4. Kotamäki, N., et al., Wireless in-situ sensor network for agriculture and water monitoring on a river basin scale in Southern Finland: Evaluation from a data user's perspective. Sensors, 2009. 9(4): p. 2862-2883.

  4. Metaphor in Natural Resource Gaming: Insights from the RIVER BASIN GAME

    Science.gov (United States)

    Lankford, Bruce; Watson, Drennan

    2007-01-01

    The RIVER BASIN GAME is a dialogue tool for decision makers and water users tested in Tanzania and Nigeria. It comprises a physical representation of a river catchment. A central channel flows between an upper watershed and a downstream wetland and has on it several intakes into irrigation systems. Glass marbles, representing water, roll down the…

  5. Examination of catchment areas for public transport

    DEFF Research Database (Denmark)

    Landex, Alex; Hansen, Stephen; Andersen, Jonas Lohmann Elkjær

    2006-01-01

    The paper presents a method to examine the catchment areas for stops in high quality public transport systems based on the street network in the examined area. This is achieved by implementing the Service Area functions from the ArcGIS extension Network Analyst. The method is compared to a more...... simple method using only the Euclidean distance from the examined stop and the paper describes the differences in detail-level of the results. Furthermore, the paper describes how the Service Area method can be used to examine increments in the catchment areas by adding extra entrances to stations or by...... improvements are well suited for examinations of changes in station entrances and/or street network....

  6. Design of a Rainwater Catchment System

    Directory of Open Access Journals (Sweden)

    Neil Cammardella

    2011-01-01

    Full Text Available Certain dimensions of a rainwater catchment and storage system were optimized using climatological and sociological data. Using only daily demand and average daily rain fall data, the following dimensions were optimized: 1 The horizontal roof area needed to collect the daily demand of water, 2 The tank size needed to store all the water collected during a heavy rain event, 3 When full, how long the tank will be able to provide water without rain, and 4 The diameter of the outlet flow orifice. With these calculations, we can design a rainwater catchment system that can capture the daily demand and store excess water for use during periods of low rain.

  7. Variability in riparian zone potential and actual evapotranspiration in a 1st order agricultural catchment in Southern Ontario, Canada

    Directory of Open Access Journals (Sweden)

    M. C. English

    2002-02-01

    Full Text Available Micrometeorological and hydrological measurements were made over one growing season using automatic weather stations and weighing lysimeters at several locations within a multiple land-use agricultural catchment in Southern Ontario. This paper compares modelled potential evapotranspiration (PET and measured actual evapotranspiration (AET values obtained from the soil weighing lysimeters, and determines the spatial variability in riparian zone AET in a multiple land-use agricultural watershed in Southern Ontario. Two sites were chosen in two different riparian areas of the watershed, representing the surface conditions dominant in the upper and lower reaches of the basin. The results indicated that AET was higher in the northern end of the basin than in the southern portion of the basin, while the hydrological and energy balance components were similar at both sites. The causes of the different rates are attributed to the surrounding vegetation on adjacent fields and the differing wind regimes.

  8. Creating a catchment perspective for river restoration

    OpenAIRE

    L. Benda; MILLER, D; J. Barquín

    2011-01-01

    One of the major challenges in river restoration is to identify the natural fluvial landscape in catchments with a long history of river control. Intensive land use on valley floors often predates the earliest remote sensing: levees, dikes, dams, and other structures alter valley-floor morphology, river channels and flow regimes. Consequently, morphological patterns indicative of the fluvial landscape including multiple channels, extensive floodplains, wetlands, and fluvial-riparian and tribu...

  9. Tritium balance modeling in a macroscale catchment

    International Nuclear Information System (INIS)

    The Institute of Hydrology at the Freiburg University (IHF) is working in cooperation with the German Federal Institute of Hydrology (BfG) on a project implementing tritium data into modeling concepts of large river systems. Tritium concentrations that are measured in precipitation (Global Network of Isotopes in Precipitation - GNIP) and discharge (BfG - HYDABA data base) are combined with information on water balance components on monthly basis over a period of 50 years. Precipitation and potential evapotranspiration were calculated from the German Weather Authority (DWD). The TRIBIL software was developed to process a large amount of data sets. It allows considering tritium input from precipitation, nuclear power plants and channel systems. Evapotranspiration from land and water surface as well as snow cover are considered for calculations of infiltrating water. Beneath a direct runoff component the amount of infiltrating water is distinguished into fast and slow groundwater reservoirs were each consists of a mobile and immobile fraction. The amount of tritium stored in these groundwater fractions is calculated using discharge recession curve analyses. An outline of the model structure as well as results for the river systems Fulda, Werra and Weser-1 is presented. A comparison of measured and modeled tritium concentrations in discharge showed considerable fits. Modeling efficiencies are around 0.8. The results allow an interpretation of storage volumes and residence times of the supposed groundwater reservoirs. Because there is no influence through nuclear power plants, tritium processing industries and channels the Fulda and Werra catchments serve as a reference for continuing studies in the Weser catchment (48.300 km2). An implementation of tritium emission by nuclear power plants will be considered with extending catchment site. Including the conservative tracer tritium into large scale modeling is a rather new approach. Feasibilities and possibilities are

  10. Influence of topography and forestry on catchments

    OpenAIRE

    Sørensen, Rasmus,

    2009-01-01

    The dynamic development of terrestrial and aquatic environments in boreal catchments is controlled by the factors of parent material, climate, topography, biota, time, and anthropogenic activity. This thesis explores two of these factors, topography and the anthropogenic activity of forestry, as well as their control on the redistribution of solutes in the landscape. On a local scale for two undisturbed sites, the calculation of the topographical wetness index, TWI, was varied to better corre...

  11. Improving Runoff Estimation at Ungauged Catchments

    OpenAIRE

    Zelelew, Mulugeta

    2012-01-01

    Water infrastructures have been implemented to support the vital activities of human society. The infrastructure developments at the same time have interrupted the natural catchment response characteristics, challenging society to implement effective water resources planning and management strategies. The Telemark area in southern Norway has seen a large number of water infrastructure developments, particularly hydropower, over more than a century. Recent developments in decision support tool...

  12. Nitrogen leaching in small agricultural catchments

    OpenAIRE

    Kyllmar, Katarina

    2004-01-01

    Nitrogen (N) leaching from arable land to the aquatic environment is considered a serious problem. Small agricultural monitoring catchments in Sweden were used for the application and testing of model-based methods for quantification of N leaching from arable fields, and for analysis of measured data. The physically-based modelling system SOILNDB was used in two different approaches for quantification of N leaching; by direct simulations using monitored field data and by producing field N lea...

  13. Updating river basin models with radar altimetry

    DEFF Research Database (Denmark)

    Michailovsky, Claire Irene B.

    -applications include the impact analysis of planned hydraulic structures or land use changes and the predicted impact of climate change on water availability. One of the obstacles hydrologists face in setting up river basin models is data availability, whether because the datasets needed do not exist or because of....... Many types of RS are now routinely used to set up and drive river basin models. One of the key hydrological state variables is river discharge. It is typically the output of interest for water allocation applications and is also widely used as a source of calibration data as it presents the integrated...... response of a catchment to meteorological forcing. While river discharge cannot be directly measured from space, radar altimetry (RA) can measure water level variations in rivers at the locations where the satellite ground track and river network intersect called virtual stations or VS. In this PhD study...

  14. Evaluation of the impact of farming activity in the water quality in surface catchment areas in hydrographic basin from Mogi-Guacu and Pardo Rivers, Sao Paulo; Avaliacao do impacto da atividade agropecuaria na qualidade da agua em areas de captacao superficial nas bacias hidrograficas dos Rios Mogi-Guacu e Pardo, Sao Paulo

    Energy Technology Data Exchange (ETDEWEB)

    Katsuoka, Lidia

    2001-07-01

    This study was performed in 10 small basins located in the Mogi-Guacu and Pardo Rivers, in the Northeastern area of Sao Paulo State. The land belonging of these basins is used to grow row crops of potato, coffee and pasture areas. This study aimed to characterize small basins, to evaluate water and sediment quality and to correlate basic aspects of climatology, hydrology, toxicology and land uses to the physical, chemical and toxicological characteristics of the water in the streams. Geographic Information System (GIS) was used as a tool of evaluation of land uses and risk assessment was performed for a final evaluation. The samplings were carried out from June/1999 to June/2000 in the 13 collecting points. It was verified that water quality is dependent upon the rainy and dry periods and the harvest periods. In the beginning of rainy periods were found large concentrations of metals and traces of herbicides leachate from soil and, in the dry period the same event was verified, caused by concentration of the water. In August, September and October phosphorus concentrations were very low getting an improvement in the water quality. Al, Fe and Mn are majority elements of chemical compositions of rocks of the study area, and exceed the Brazilian Guidelines. The stream waters were classified as 44% oligotrophic, 42% mesotrophic and 14% eutrophic. Jaguari-Mirim River presented the largest values of Trophic Index (TI). Sediment analyses showed a great variety of organic compounds coming from anthropogenic activities (industrial and farming activity). Toxicity tests with hyalella azteca in the sediments presented toxicity for sediments from Sao Joao da Boa Vista and Divinolandia. A methodology was developed for organochlorinated pesticides by gas chromatography coupled to mass spectrometry (GCMS). The presence of organochlorinated pesticides was not verified. (author)

  15. The geochemical quality of soils in the Clyde basin, Scotland, UK : main controls and anthropogenic impacts [abstract only

    OpenAIRE

    Fordyce, Fiona; Everett, Paul; Bearcock, Jenny; Lister, Bob

    2015-01-01

    Recently, the British Geological Survey’s (BGS) Geochemical Baseline Survey of the Environment (G-BASE) project carried out extensive surveys of rural and urban soil quality in the River Clyde catchment (Clyde basin) on the west coast of Scotland. The Clyde basin is interesting as it extends from a rural upland environment in the south, to the River Clyde estuary in the north. The catchment contains an historic lead mining area known as Leadhills that was active until the mid 20th century. In...

  16. Selected Micropollutants as Indicators in a Karst Catchment

    Science.gov (United States)

    Zirlewagen, Johannes; Schiperski, Ferry; Hillebrand, Olav; Nödler, Karsten; Licha, Tobias; Scheytt, Traugott

    2015-04-01

    High flow dynamics and variations in water quality are typical for karst springs and reflect the complex interaction of different flow and storage components within a karst system. Event-based monitoring of mobile micropollutants in spring water combined with information on their input is used (1) to quantify the impact of certain contamination scenarios on spring water quality and (2) to gain additional information on the intrinsic characteristics of a karst system. We employ the artificial sweeteners acesulfame and cyclamate as source specific indicators for sewage along with the herbicides atrazine and isoproturon for agriculture. The study site is the 45 km² rural catchment of the perennial karst spring Gallusquelle in SW-Germany (mean discharge: 0.5 m³/s). Overflow events of a stormwater detention basin (SDB, combined sewer system) are known to impact water quality. Most of the sewer system is situated in the SW of the catchment. Most agricultural land is found in the NE. Neither atrazine nor significant amounts of isoproturon were detected in wastewater. Concentrations and mass fluxes of acesulfame and cyclamate in wastewater were determined. The combined evaluation of the persistent compound acesulfame with the rather degradable cyclamate allows for the distinction of long and short transit times and thus slow and fast flow components. The same applies for atrazine (persistent) and isoproturon (degradable). In Germany, acesulfame was licensed in 1990, atrazine was banned shortly after, in 1991. During low flow conditions only atrazine (max. 4 ng/L) and acesulfame (max. 20 ng/L) were detected in spring water. After a recharge event without SDB overflow concentrations as well as mass fluxes of both compounds decreased, reflecting an increasing portion of event water in spring discharge. A breakthrough of isoproturon (max. 9 ng/L) indicated the arrival of water from croplands. After a recharge event accompanied by a SDB overflow cyclamate was detected at max

  17. Characterization of physical parameters and environmental sanitation for experimental-representative catchment located in the lowlands of Jacarepaguá, Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Luciene Pimentel da Silva

    2010-12-01

    Full Text Available This paper aimed to evaluate the physical characteristics and environmental sanitation aspects for a drainage area inserted in the region of Morto river catchment, taken as experimental and representative of Jacarepaguá Lowland Basin in Rio de Janeiro, where city´s growth is taking place very fast. It is expected that this study will support the development of public policies that may guide the conservation of water and sustainable development of the region. The methodology used for watershed delimitation and the physical characteristics calculation involved the application of small computational procedures associated to ArcGis 9.2, ArcHydro®. It was determined the area, the perimeter, the compactness index, shape factor, drainage density, average extension of runoff and catchment´s slope. The observed low slope along the river coast combined with the physical parameters of the basin, enabled to conclude that this catchment is susceptible to floods especially during concomitant events of high tide and heavy rain. The analysis of social and environmental sanitation aspects took into account IBGE`s 2000 Census results. It was observed that illiteracy rates for the catchment area was doubled of that observed for the city as whole and that services such as water supply, sewage and garbage collection are more precarious in the catchment area than in the neighborhood of Jacarepaguá or the city of Rio de Janeiro. In relative terms, sewage collection was in the worst situation while the garbage collection services were in the best for the studied basin.

  18. Acid rain project biosurveys of streams in the Wastwater catchment

    OpenAIRE

    Prigg, R.F.

    1985-01-01

    This is the Acid rain project biosurveys of streams in the Wastwater catchment produced by the North West Water Authority in 1985. This report forms part of a series on component biological investigations, identified by location or topic, within the acid rain project. Reporting of the Wastwater catchment data would not have been given priority ordinarily, but it has been brought forward to coincide with J. Robinson's reporting of his investigations of land use and liming in the catchment. Thi...

  19. Transferring model uncertainty estimates from gauged to ungauged catchments

    OpenAIRE

    Bourgin, F.; V. Andréassian; Perrin, C.; L. Oudin

    2014-01-01

    Predicting streamflow hydrographs in ungauged catchments is a challenging issue, and accompanying the estimates with realistic uncertainty bounds is an even more complex task. In this paper, we present a method to transfer model uncertainty estimates from gauged to ungauged catchments and we test it over a set of 907 catchments located in France. We evaluate the quality of the uncertainty estimates based on three expected qualities: reliab...

  20. Transferring global uncertainty estimates from gauged to ungauged catchments

    OpenAIRE

    Bourgin, F.; V. Andréassian; Perrin, C.; L. Oudin

    2015-01-01

    Predicting streamflow hydrographs in ungauged catchments is challenging, and accompanying the estimates with realistic uncertainty bounds is an even more complex task. In this paper, we present a method to transfer global uncertainty estimates from gauged to ungauged catchments and we test it over a set of 907 catchments located in France, using two rainfall–runoff models. We evaluate the quality of the uncertainty estimates based on three...

  1. The LOCAR hydrogeological infrastructure in the tern catchment

    OpenAIRE

    Adams, Brian; Peach, Denis; Bloomfield, John

    2003-01-01

    This report describes the hydrogeological infrastructure that was installed in the Tern catchment in Shropshire to support the Lowland Catchment Research (LOCAR) Thematic Research Programme. The objectives of the LOCAR Programme are briefly described as are the management structure that was used to achieve those objectives. This is followed by a description of the Tern catchment and a brief overview of the financial support for the whole LOCAR programme. A discussion of the des...

  2. Influence of vegetation on the water balance of catchments

    OpenAIRE

    Kozakiv, Dejan

    2013-01-01

    It is a well known fact that amount and type of catchment vegetation will affect its water balance. Through process of precipitation interception, vegetation coverage plays an important role in regulating processes as evapotranspiration and runoff. Many studies have shown significant increase of water surface runoff, discharge and water yield after forest cover was removed. A clear conclusion can be drawn from this: grassed catchments decrease catchment evapotranspiration, while the opposi...

  3. Recognizing hydroclimate of Khotbeh Sara catchment area via GIS

    OpenAIRE

    AZAD, Mohammad Reza Afshari

    2015-01-01

    Abstract. Objective of studying hydroclimatology is studying effects of climate in water balance of the catchment. Current research has been conducted to study climatic and hydroclimatic characteristics of catchment area of Khotbeh Sara via hydrological modeling of the catchment. The main purpose of this research is recognition of climatic parameters dominant in this area and its effect on surface flows and required activities were done to gain this purpose. Physical characteristics of catchm...

  4. A catchment scale water balance model for FIFE

    OpenAIRE

    Famiglietti, J.S.; E. F. Wood; Sivapalan, M.; Thongs, D. J

    1992-01-01

    A catchment scale water balance model is presented and used to predict evaporation from the King's Creek catchment at the First ISLSCP Field Experiment site on the Konza Prairie, Kansas. The model incorporates spatial variability in topography, soils, and precipitation to compute the land surface hydrologie fluxes. A network of 20 rain gages was employed to measure rainfall across the catchment in the summer of 1987. These data were spatially interpolated and used to drive the model during st...

  5. Predicting Surface Runoff from Catchment to Large Region

    OpenAIRE

    Hongxia Li; Yongqiang Zhang; Xinyao Zhou

    2015-01-01

    Predicting surface runoff from catchment to large region is a fundamental and challenging task in hydrology. This paper presents a comprehensive review for various studies conducted for improving runoff predictions from catchment to large region in the last several decades. This review summarizes the well-established methods and discusses some promising approaches from the following four research fields: (1) modeling catchment, regional and global runoff using lumped conceptual rainfall-runof...

  6. Using Isotope Methods to Assess Groundwater Recharge in Some Hydraulic Catchments in a Semiarid Region in Central Tunisia

    International Nuclear Information System (INIS)

    Water resource issues constitute a major concern in arid and semiarid areas in Tunisia. To meet rising demand for different human activities considerable importance is being given to improving the natural groundwater recharge by the installation of hydraulic catchments. In central Tunisia, numerous retention sites and dams have been built since 1990, for example, the el Ogla dam in the Nadhour-Saouaf basin. In order to determine the implication of these hill reservoirs on the hydrodynamic functioning and water quality of the aquifer system, hydrochemical (major elements) and isotopic methods have been employed. The interpretation of these results showed that the shallow aquifer is recharged mainly by surface water and water dam infiltration from the el Ogla and Sahel catchments. A tentative isotopic mass balance based on stable isotope contents leads to the quantification of the artificial recharge rate, which ranges between 42% and 86% of precipitation in the humid period. (author)

  7. Late Holocene High Discharge and Erosion Events Inferred from Sediment Proxies and Catchment Geomorphology, Lake Vuoksjávrátje, NW Sweden

    Science.gov (United States)

    Berntsson, A.; Jansson, K. N.; Kylander, M. E.; De Vleeschouwer, F.; Bertrand, S.

    2014-12-01

    Alpine lakes in NW Sweden are highly sensitive to variations in catchment erosion and in precipitation. Previous studies aimed at reconstructing past summer temperatures have suggested that this sensitivity may influence chironomid species composition enough to cause bias in quantitative temperature reconstructions. In this study we have analysed lake sediments covering the last 5100 years from Lake Vuoksjávrátje in NW Sweden and catchment geomorphology with the aim to separate between different erosional regimes in the lake and its catchment and to identify sediment sources and processes behind sediment deposition in the lake basin. Methods include XRF core scanning, grain size analysis, chironomid analysis, TOC and C/N analysis and detailed mapping of geomorphology. From the integrated results we identify time intervals with increased catchment erosion, inferred to result from intense precipitation. Based on the combined proxy data it was concluded that a major flood event took place at the Vindelfjällen site c. 2800 cal BP, unique for the 5100-year long record. The chironomid species composition shows stronger influence from wetland surface erosion at c. 2800 cal BP and during the last c. 1000 years. By combining multi-proxy lake sediment analysis with study of catchment geomorphology it is possible to improve the understanding of Late Holocene hydro-climatic change and how it may influence Arctic alpine lakes.

  8. Partitioning of catchment water budget and its implications for ecosystem carbon exchange

    Directory of Open Access Journals (Sweden)

    D. Lee

    2010-06-01

    Full Text Available Spatially averaged annual carbon budget is one of the key information needed to understand ecosystem response and feedback to climate change. Water availability is a primary constraint of carbon uptake in many ecosystems and therefore the estimation of ecosystem water use may serve as an alternative to quantify Gross Primary Productivity (GPP. To examine this concept, we estimated a long-term steady state water budget for the Han River basin (~26 000 km2 in Korea and examined its application for catchment scale carbon exchange. For this, the catchment scale evapotranspiration (ET was derived from the long term precipitation (P and discharge (Q data. Then, using stable isotope data of P and Q along with other hydrometeorological information, ET was partitioned into evaporation from soil and water surfaces (ES, evaporation from intercepted rainfall (EI, and transpiration (T. ES was identified as a minor component of ET in the study areas regardless of the catchment scales. The annual T, estimated from ET after accounting for EI and ES for the Han River basin from 1966 to 2007, was 22~31% of annual P and the proportion decreased with increasing P. Assuming that T further constrains the catchment scale GPP in terms of water use efficiency (WUE, we examined the possibility of using T as a relative measure for the strength and temporal changes of carbon uptake capacity. The proposed relationship would provide a simple and practical way to assess the spatial distribution of ecosystem GPP, provided the WUE estimates in terms of GPP/T at ecosystem scale could be obtained. For carbon and water tracking toward a sustainable Asia, ascertaining such a spatiotemporally representative WUE and their variability is a

  9. Contextualising impacts of logging on tropical rainforest catchment sediment dynamics using the stratigraphic record of in-channel bench deposits

    Science.gov (United States)

    Blake, Will; Walsh, Rory; Bidin, Kawi; Annammala, Kogila

    2015-04-01

    It is widely recognised that commercial logging and conversion of tropical rainforest to oil palm plantation leads to enhanced fluvial sediment flux to the coastal zone but the dynamics of delivery and mechanisms that act to retain sediment and nutrients within rainforest ecosystems, e.g. riparian zone and floodplain storage, are poorly understood and underexploited as a management tool. While accretion of lateral in-channel bench deposits in response to forest clearance has been demonstrated in temperate landscapes, their development and value as sedimentary archives of catchment response to human disturbance remains largely unexplored in tropical rainforest river systems. Working within the Segama River basin, Sabah, Malaysian Borneo, this study aimed to test the hypothesis that (1) lateral bench development in tropical rainforest rivers systems is enhanced by upstream catchment disturbance and that (2) the sedimentary record of these deposits can be used to infer changes in sediment provenance and intensification of sediment flux associated with logging activities. Sediment cores were taken from in-channel bench deposits with upstream catchment contributing areas of 721 km2 and 2800 km2 respectively. Accretion rates were determined using fallout 210Pb and 137Cs and the timing of peak accumulation was shown to correspond exactly with the known temporal pattern of logging and associated fluvial sediment response over the period 1980 to present following low pre-logging rates. Major and minor element geochemistry of deposits was used to assess the degree of weathering that deposited sediment had experienced. This was linked to surface (heavily weathered) and subsurface (less weathered) sediment sources relating to initial disturbance by logging and post-logging landsliding responses respectively. A shift in the dominant source of deposited material from surface (i.e. topsoil) to subsurface (i.e. relatively unweathered subsoil close to bedrock) origin was observed

  10. Characterization of physical parameters and environmental sanitation for experimental-representative catchment located in the lowlands of Jacarepaguá, Rio de Janeiro, Brazil

    OpenAIRE

    Luciene Pimentel da Silva; Ezer Urpia Rosa; Caroline Pereira Pires da Silva

    2010-01-01

    This paper aimed to evaluate the physical characteristics and environmental sanitation aspects for a drainage area inserted in the region of Morto river catchment, taken as experimental and representative of Jacarepaguá Lowland Basin in Rio de Janeiro, where city´s growth is taking place very fast. It is expected that this study will support the development of public policies that may guide the conservation of water and sustainable development of the region. The methodology used for watershed...

  11. Solid discharge and landslide activity at basin scale

    Science.gov (United States)

    Ardizzone, F.; Guzzetti, F.; Iadanza, C.; Rossi, M.; Spizzichino, D.; Trigila, A.

    2012-04-01

    This work presents a preliminary analysis aimed at understanding the relationship between landslide sediment supply and sediment yield at basin scale in central and southern Italy. A database of solid discharge measurements regarding 116 gauging stations, located along the Apennines chain in Italy, has been compiled by investigating the catalogues, named Annali Idrologici, published by Servizio Idrografico e Mareografico Italiano in the period from 1917 to 1997. The database records several information about the 116 gauging stations, and especially reports the sediment yield monthly measurements (103 ton) and the catchments area (km2). These data have been used to calculate the average solid yield and the normalized solid yield for each station in the observation period. The Italian Landslide Inventory (Progetto IFFI) has been used to obtained the size of the landslides, in order to estimate the landslide mobilization rates. The IFFI Project funded by the Italian Government is realized by ISPRA (Italian National Institute for Environmental Protection and Research - Geological Survey of Italy) in partnership with the 21 Regions and Self Governing Provinces. 21 of the 116 gauging stations and the related catchments have been selected on the basis of the length of the solid discharge observation period and excluding the catchments with dams located upstream the stations. The landslides inside the selected catchments have been extracted from the IFFI inventory, calculating the planimetric area of each landslide. Considering both the shallow and deep landslides, the landslide volume has been estimated using an empirical power law relation (landslide area vs. volume). The total landslide volume in the study areas and the average sediment yield measured at the gauging stations have been compared, analysing the behaviour of the basins which drainage towards the Tyrrhenian sea and the basins which drainage towards the Adriatic sea.

  12. ANN modeling for flood prediction in the upstream Eure's catchment (France)

    Science.gov (United States)

    Kharroubi, Ouissem; masson, Eric; Blanpain, Olivier; Lallahem, Sami

    2013-04-01

    Rainfall-Runoff relationship at basin scale is strongly depending on the catchment complexity including multi-scale interactions. In extreme events cases (i.e. floods and droughts) this relationship is even more complex and differs from average hydrological conditions making extreme runoff prediction very difficult to achieve. However, flood warning, flood prevention and flood mitigation rely on the possibility to predict both flood peak runoff and lag time. This point is crucial for decision making and flood warning to prevent populations and economical stakes to be damaged by extreme hydrological events. Since 2003 in France, a dedicated state service is in charge of producing flood warning from national level (i.e. SCHAPI) to regional level (i.e. SPC). This flood warning service is combining national weather forecast agency (i.e. Meteo France) together with a fully automated realtime hydrological network (i.e. Rainfall-Runoff) in order to produce a flood warning national map online and provide a set of hydro-meteorological data to the SPC in charge of flood prediction from regional to local scale. The SPC is in fact the flood service delivering hydrological prediction at operational level for decision making about flood alert for municipalities and first help services. Our research in collaboration with the SPC SACN (i.e. "Seine Aval et fleuves Côtiers Normands") is focused on the implementation of an Artificial Neural Network model (ANN) for flood prediction in deferent key points of the Eure's catchment and main subcatchment. Our contribution will focus on the ANN model developed for Saint-Luperce gauging station in the upstream part of the Eure's catchment. Prediction of extreme runoff at Saint-Luperce station is of high importance for flood warning in the Eure's catchment because it gives a good indicator on the extreme status and the downstream propagation of a potential flood event. Despite a good runoff monitoring since 27 years Saint Luperce flood

  13. Estimating the input of wastewater-born micropollutants in a rural karst catchment (Gallusquelle, Germany)

    Science.gov (United States)

    Zirlewagen, Johannes; Hillebrand, Olav; Nödler, Karsten; Schiperski, Ferry; Scheytt, Traugott; Licha, Tobias

    2013-04-01

    The main focus of the AGRO research project is on the use of various micropollutants as indicators (e.g. for wastewater) in the catchment of the karst spring Gallusquelle, Swabian Alb. For modeling the micropollutants' fate in the subsurface and their occurrence in spring water, reliable estimates of the spatio-temporal input, i.e. input functions, are crucial. Therefore potential sources for wastewater-born substances are identified. These are the combined sewer system with a stormwater retention basin (untreated wastewater) and the river Fehla (treated wastewater). The micropollutants' concentrations and loads in the potentially infiltrating waters are estimated on the one hand by local water and substance consumption data and on the other hand by water sample analysis and stream gauging. The spring's discharge varies from 0.2-2.0 m³/s with an average of 0.5 m³/s. Treated spring water serves as drinking water for 45 000 people. The catchment area measures 45 km² and is rural in character with 55% forest, 27% grassland, 15% agriculture and 3% residential/industrial. Industrial activity is restricted to a few minor textile and metal works. There are around 4 000 inhabitants and except for a few farms, all households are connected to the public sewer system. The only surface water within the catchment is the stream Fehla, which forms a part of the catchment boundary. It was formerly identified as a sinking stream with an ephemeral part in the lower course. Connections to the Gallusquelle spring were proven by several tracer tests conducted in the 1960's, when the river started to become perennial over the whole course due to heavy colmatation. During a one week campaign, samples of wastewater and river water were taken three times per day. Additionally, hourly samples were taken during a 24 h period. Water samples were analysed for major ions and 58 micropollutants, including pharmaceuticals, stimulants (as caffeine), the artificial sweeteners acesulfame and

  14. Identifying residence times and streamflow generation processes using δ18O and δ2H in meso-scale catchments in the Abay/Upper Blue Nile, Ethiopia

    OpenAIRE

    Teklaeb, S.; Wenninger, J.W.; Uhlenbrook, S.

    2013-01-01

    Measurements of the stable isotopes oxygen-18 (18O) and deuterium (2H) were carried out in two meso-scale catchments, Chemoga (358 km2) and Jedeb (296 km2) south of Lake Tana, Abay/Upper Blue Nile basin, Ethiopia. The region is of paramount importance for the water resources in the Nile basin. Stable isotope composition in precipitation, spring water and streamflow were analyzed (i) to characterize the spatial and temporal variations of water fluxes; (ii) to estimate the mean residence time o...

  15. Lithogenic and cosmogenic tracers in catchment hydrology

    Energy Technology Data Exchange (ETDEWEB)

    Nimz, G.J.

    1995-01-01

    A variety of physical processes affect solute concentrations within catchment waters. The isotopic compositions of the solutes can indicate which processes have determined the observed concentrations. These processes together constitute the physical history of the water, which is one of the primary concerns in hydrology. Many groundwater solutes are derived as a result of interaction between the water and the rock and/or soil within the system. These are termed {open_quotes}lithogenic{close_quotes} solutes. The isotopic compositions of these solutes provide information regarding rock-water interactions. Many other solutes have their isotopic compositions determined both internally and externally to the catchment system. Important members of this group include solutes that have isotopic compositions produced by atomic particle interactions with other nuclides. The source of the atomic particles can be cosmic radiation (producing {open_quotes}cosmogenic{close_quotes} nuclides in the atmosphere and land surface), anthropogenic nuclear reactions (producing {open_quotes}thermonuclear{close_quotes} nuclides), or radioactive and fission decay of naturally-occurring elements, such as U and Th (producing {open_quotes}in-situ{close_quotes} lithogenic nuclides in the deep subsurface). Current language usage often combines all of the atomic particle-produced nuclides under the heading {open_quotes}cosmogenic nuclides{close_quotes}, and for simplicity we will often follow that usage, although always clearly indicating which variety is being discussed. This paper addresses the processes that affect the lithogenic and cosmogenic solute compositions in groundwater, and how these compositions can therefore be used in integrative ways to understand the physical history of groundwater within a catchment system.

  16. Lithogenic and cosmogenic tracers in catchment hydrology

    International Nuclear Information System (INIS)

    A variety of physical processes affect solute concentrations within catchment waters. The isotopic compositions of the solutes can indicate which processes have determined the observed concentrations. These processes together constitute the physical history of the water, which is one of the primary concerns in hydrology. Many groundwater solutes are derived as a result of interaction between the water and the rock and/or soil within the system. These are termed open-quotes lithogenicclose quotes solutes. The isotopic compositions of these solutes provide information regarding rock-water interactions. Many other solutes have their isotopic compositions determined both internally and externally to the catchment system. Important members of this group include solutes that have isotopic compositions produced by atomic particle interactions with other nuclides. The source of the atomic particles can be cosmic radiation (producing open-quotes cosmogenicclose quotes nuclides in the atmosphere and land surface), anthropogenic nuclear reactions (producing open-quotes thermonuclearclose quotes nuclides), or radioactive and fission decay of naturally-occurring elements, such as U and Th (producing open-quotes in-situclose quotes lithogenic nuclides in the deep subsurface). Current language usage often combines all of the atomic particle-produced nuclides under the heading open-quotes cosmogenic nuclidesclose quotes, and for simplicity we will often follow that usage, although always clearly indicating which variety is being discussed. This paper addresses the processes that affect the lithogenic and cosmogenic solute compositions in groundwater, and how these compositions can therefore be used in integrative ways to understand the physical history of groundwater within a catchment system

  17. Describing Ecosystem Complexity through Integrated Catchment Modeling

    Science.gov (United States)

    Shope, C. L.; Tenhunen, J. D.; Peiffer, S.

    2011-12-01

    Land use and climate change have been implicated in reduced ecosystem services (ie: high quality water yield, biodiversity, and agricultural yield. The prediction of ecosystem services expected under future land use decisions and changing climate conditions has become increasingly important. Complex policy and management decisions require the integration of physical, economic, and social data over several scales to assess effects on water resources and ecology. Field-based meteorology, hydrology, soil physics, plant production, solute and sediment transport, economic, and social behavior data were measured in a South Korean catchment. A variety of models are being used to simulate plot and field scale experiments within the catchment. Results from each of the local-scale models provide identification of sensitive, local-scale parameters which are then used as inputs into a large-scale watershed model. We used the spatially distributed SWAT model to synthesize the experimental field data throughout the catchment. The approach of our study was that the range in local-scale model parameter results can be used to define the sensitivity and uncertainty in the large-scale watershed model. Further, this example shows how research can be structured for scientific results describing complex ecosystems and landscapes where cross-disciplinary linkages benefit the end result. The field-based and modeling framework described is being used to develop scenarios to examine spatial and temporal changes in land use practices and climatic effects on water quantity, water quality, and sediment transport. Development of accurate modeling scenarios requires understanding the social relationship between individual and policy driven land management practices and the value of sustainable resources to all shareholders.

  18. Evaluation of TOPLATS on three Mediterranean catchments

    Science.gov (United States)

    Loizu, Javier; Álvarez-Mozos, Jesús; Casalí, Javier; Goñi, Mikel

    2016-08-01

    Physically based hydrological models are complex tools that provide a complete description of the different processes occurring on a catchment. The TOPMODEL-based Land-Atmosphere Transfer Scheme (TOPLATS) simulates water and energy balances at different time steps, in both lumped and distributed modes. In order to gain insight on the behavior of TOPLATS and its applicability in different conditions a detailed evaluation needs to be carried out. This study aimed to develop a complete evaluation of TOPLATS including: (1) a detailed review of previous research works using this model; (2) a sensitivity analysis (SA) of the model with two contrasted methods (Morris and Sobol) of different complexity; (3) a 4-step calibration strategy based on a multi-start Powell optimization algorithm; and (4) an analysis of the influence of simulation time step (hourly vs. daily). The model was applied on three catchments of varying size (La Tejeria, Cidacos and Arga), located in Navarre (Northern Spain), and characterized by different levels of Mediterranean climate influence. Both Morris and Sobol methods showed very similar results that identified Brooks-Corey Pore Size distribution Index (B), Bubbling pressure (ψc) and Hydraulic conductivity decay (f) as the three overall most influential parameters in TOPLATS. After calibration and validation, adequate streamflow simulations were obtained in the two wettest catchments, but the driest (Cidacos) gave poor results in validation, due to the large climatic variability between calibration and validation periods. To overcome this issue, an alternative random and discontinuous method of cal/val period selection was implemented, improving model results.

  19. Identification of the main attribute of river flow temporal variations in the Nile Basin

    Science.gov (United States)

    Onyutha, C.; Willems, P.

    2015-11-01

    Temporal variation of monthly flows was investigated at 18 Discharge Measurement Stations (DMS) within the Nile Basin in Africa. The DMS were grouped using a clustering procedure based on the similarity in the flow variation patterns. The co-variation of the rainfall and flow was assessed in each group. To investigate the possible change in catchment behavior, which may interfere with the flow-rainfall relationship, three rainfall-runoff models were applied to the major catchment in each group based on the data time period falling within 1940-2003. The co-occurrence of the changes in the observed and simulated overland flow was examined using the cumulative rank difference (CRD) technique and the quantile perturbation method (QPM). Two groups of the DMS were obtained. Group 1 comprises the DMS from the equatorial region and/or South Sudan, while those in Sudan, Ethiopia and Egypt form group 2. In the selected catchment of each group, the patterns of changes in terms of the CRD sub-trends and QPM anomalies for both the observed and simulated flows were in a close agreement. These results indicate that change in catchment behavior due to anthropogenic influence in the Nile basin over the selected time period was minimal. Thus, the overall rainfall-runoff generation processes of the catchments were not impacted upon in a significant way. The temporal flow variations could be attributed mainly to the rainfall variations.

  20. Modelling spring flood in the area of the Upper Volga basin

    Directory of Open Access Journals (Sweden)

    M. Helms

    2006-01-01

    Full Text Available Integrated river-basin management for the Volga river requires understanding and modelling of the flow process in its macro-scale tributary catchments. At the example of the Kostroma catchment (16 000 km2, a method combining existing hydrologic simulation tools was developed that allows operational modelling even when data are scarce. Emphasis was placed on simulation of three processes: snow cover development using a snow-compaction model, runoff generation using a conceptual approach with parameters for seasonal antecedent moisture conditions, and runoff concentration using a regionalised unit hydrograph approach. Based on this method, specific regional characteristics of the precipitation-runoff process were identified, in particular a distinct threshold behaviour of runoff generation in catchments with clay-rich soils. With a plausible overall parameterisation of involved tools, spring flood events could successfully be simulated. Present paper mainly focuses on the simulation of a 16-year sample of snowmelt events in a meso-scale catchment. An example of regionalised simulation in the scope of the modelling system "Flussgebietsmodell" shows the capabilities of developed method for application in macro-scale tributary catchments of the Upper Volga basin.

  1. Design of a Rainwater Catchment System

    OpenAIRE

    Neil Cammardella

    2011-01-01

    Certain dimensions of a rainwater catchment and storage system were optimized using climatological and sociological data. Using only daily demand and average daily rain fall data, the following dimensions were optimized: 1) The horizontal roof area needed to collect the daily demand of water, 2) The tank size needed to store all the water collected during a heavy rain event, 3) When full, how long the tank will be able to provide water without rain, and 4) The diameter of the outlet flow orif...

  2. Hydrologic regime alteration of a Mediterranean catchment under climate change projection

    Science.gov (United States)

    Sellami, Haykel; Benabdallah, Sihem; La Jeunesse, Isabelle; Herrmann, Frank; Vanclooster, Marnik

    2014-05-01

    Most of the climate models projections for the Mediterranean basin have showed that the region will likely to experience a general tendency towards drier climate conditions with decreases in total precipitation, increases in temperature, alterations in the rainfall extreme events and droughts frequency (IPCC, 2007; Giorgi and Lionello, 2008; López-Moreno et al., 2011). The region is already suffering from water resources scarcity and vulnerability which are expected to amplify in the next century (Ludwig et al., 2011; Schneider et al., 2013). Therefore, assessing the impact of climate change on the hydrologic regime of Mediterranean catchments is with a major concern not only to scientist but also to water resources policy makers and general public. However, most of the climate change impact studies focus on the flow regime on global or regional scale rather than on the catchment scale which is more useful and more appropriate to guide practical mitigation and adaptation policy. This is because hydro-climate modeling at the local scale is confronted to the variability in climate, topography, geology, lack of observations and anthropogenic activities within the catchment. Furthermore, it is well recognized that hydrological and climate models forecasts are always affected with uncertainty making the assessment of climate change impact on Mediterranean catchment hydrology more challenging. This work aims to assess the impact of climate change on a Mediterranean catchment located in North Africa (the Chiba catchment in northeast Tunisia) through a conjunctive use of physically based hydrological model (SWAT) driven with four climate models*. Quantification of the impact of climate change has been conducted by means of the Indicators of Hydrologic Alteration (Richter et al., 1996) which are also ecologically meaningful. By comparing changes in these indicators in the reference period (1971-2000) to the projected ones in the future (2041-2070), it was possible to draw

  3. A numerical solution to define channel heads and hillslope parameters from digital topography of glacially conditioned catchments

    Science.gov (United States)

    Salcher, Bernhard; Baumann, Sebastian; Kober, Florian; Robl, Jörg; Heiniger, Lukas

    2016-04-01

    region shows a distinct increase of mean elevation from the major overdeepend valleys near the Foreland to the alpine main divide at around 4000 m.a.s.l. within a distance of only 150 km. To define channel heads we first analyzed the variations to fine-scale topography of catchments by calculating the plan curvature at low topographic wavelengths. Higher elevated catchments more frequently impacted by glacial erosion show a higher degree in topographic flattening than catchments with a lower mean elevation where rougher fluvial (steady state) channels dominate. We found that this process of glacial destruction of fine-scale topography can well be analyzed by extracting the plan curvature from a DEM (1-30 m resolution). We furthermore found that the plan curvature frequency depends on the mean elevation of a catchment. Accordingly, the correlation between mean elevation of basins and the related density of pixels with a certain curvature is highly controlled by the used curvature threshold (e.g. used range of curvature pixels). A statistically derived optimum of the negative plan curvature was taken to define a threshold for the concavity of channels. The resulting fragmented network of channel segments was then fully integrated by utilizing a steepest descent algorithm. The upstream-most point of this fully integrated network was then defined as channel head. Our approach offers not only a consistent method to derive (i) hillslope and channel parameters in formerly glaciated catchments but also to (ii) measure the degree in glacial conditioning and therefore (iii) separating non-glacial from glacial catchments.

  4. Hydrological effects of within-catchment heterogeneity of drainage density

    Science.gov (United States)

    Di Lazzaro, Michele; Zarlenga, Antonio; Volpi, Elena

    2015-02-01

    Local drainage density (dd) has been traditionally defined as the inverse of twice the distance one has to walk before encountering a channel. This formalization easily allows to derive raster-based maps of dd extracted straight off from digital elevation model data. Maps of local dd, which are continuous in space, are able to reveal the appearance of strong heterogeneities in the geological and geomorphological properties of natural landscapes across different scales. In this work we employ the information provided by these spatial maps to study the potential effects of the within-catchment variability of dd on the hydrologic response. A simple power law relationship between runoff yield at the local scale and the value of dd has been adopted; the hypothesis is supported by a large number of past empirical observations and modeling. The novel framework proposed (ddRWF) embeds this spatially variable runoff weight in the well-known Rescaled Width Function (RWF) framework, based on the more general geomorphological theory of the hydrologic response. The model is applied to four sub-basins in the Cascade Range Region (Oregon, USA) where strong contrasts in dissection patterns due the underlain geology have been broadly addressed in previous literature. The ddRWF approach is compared with the classic RWF in terms of shape, moments and peak of the simulated hydrograph response. Results hint that the variability of runoff yield due to the heterogeneity of dd (i.e. of hillslope lengths) determines a more rapid concentration of runoff, which implies shorter lag times, larger skewness and higher peak floods, especially in the case hillslope velocity is much smaller than channel velocity. The potential of the proposed framework relies on accounting for spatially variable losses related to geomorphologic heterogeneity in lumped rainfall-runoff models, still keeping the simple and robust structure of the IUH approach.

  5. Emergent Urban-Landscape Interactions in Mountain Catchments

    Science.gov (United States)

    Werner, B.; McNamara, D.; Kelso, A.; Ipiktok, T.

    2004-12-01

    The margins of mountain catchments can offer attractive residential attributes, but development is subject to an array of significant hazards. The question of how urban expansion and natural processes interact as a system to produce long-term, emergent patterns of coupled human-landscape dynamics is addressed in a model that treats natural processes on intermediate time scales on a cellular grid and urban processes using agent-based models of markets and local/regional government. In the model, shrubland vegetation grows between fires, wildfires consume vegetation and residences and promote erosion, and landslides, floods and sediment-laden debris flows damage or destroy residences. Developer agents build developments whose size and location are based on projected profits; homeowning agents buy houses based on projected appreciation and attributes such as view and commute distance. Based on their predicted effect on tax revenues, government agents approve developments; mitigate fires with prescribed burns; mitigate landslides, floods and debris flows with slope stabilization, debris basins, reservoirs and channel stabilization and entrenchment; and suppress fires. Initial investigation of the model has focused on long-time-scale behavior of the urban-wildland boundary. Mitigation measures filter out short, small-amplitude fluctuations in this boundary. As the relative time scales and interaction magnitudes characterizing natural processes, development and government action are varied, a nominally stable boundary becomes unstable to irregular, long period fluctuations that can be spatially complex. The role that market externalities play in producing nonoptimal states will be discussed. Supported by the Andrew W. Mellon Foundation.

  6. Standardised survey method for identifying catchment risks to water quality.

    Science.gov (United States)

    Baker, D L; Ferguson, C M; Chier, P; Warnecke, M; Watkinson, A

    2016-06-01

    This paper describes the development and application of a systematic methodology to identify and quantify risks in drinking water and recreational catchments. The methodology assesses microbial and chemical contaminants from both diffuse and point sources within a catchment using Escherichia coli, protozoan pathogens and chemicals (including fuel and pesticides) as index contaminants. Hazard source information is gathered by a defined sanitary survey process involving use of a software tool which groups hazards into six types: sewage infrastructure, on-site sewage systems, industrial, stormwater, agriculture and recreational sites. The survey estimates the likelihood of the site affecting catchment water quality, and the potential consequences, enabling the calculation of risk for individual sites. These risks are integrated to calculate a cumulative risk for each sub-catchment and the whole catchment. The cumulative risks process accounts for the proportion of potential input sources surveyed and for transfer of contaminants from upstream to downstream sub-catchments. The output risk matrices show the relative risk sources for each of the index contaminants, highlighting those with the greatest impact on water quality at a sub-catchment and catchment level. Verification of the sanitary survey assessments and prioritisation is achieved by comparison with water quality data and microbial source tracking. PMID:27280603

  7. Analysis of groundwater flow in mountainous, headwater catchments with permafrost

    Science.gov (United States)

    Evans, Sarah G.; Ge, Shemin; Liang, Sihai

    2015-12-01

    Headwater catchments have a direct impact on the water resources of downstream lowland regions as they supply freshwater in the form of surface runoff and discharging groundwater. Often, these mountainous catchments contain expansive permafrost that may alter the natural topographically controlled groundwater flow system. As permafrost could degrade with climate change, it is imperative to understand the effect of permafrost on groundwater flow in headwater catchments. This study characterizes groundwater flow in mountainous headwater catchments and evaluates the effect of permafrost in the context of climate change on groundwater movement using a three-dimensional, finite element, hydrogeologic model. The model is applied to a representative headwater catchment on the Qinghai-Tibet Plateau, China. Results from the model simulations indicate that groundwater contributes significantly to streams in the form of baseflow and the majority of groundwater flow is from the shallow aquifer above the permafrost, disrupting the typical topographically controlled flow pattern observed in most permafrost-free headwater catchments. Under a warming scenario where mean annual surface temperature is increased by 2°C, reducing the areal extent of permafrost in the catchment, groundwater contribution to streamflow may increase three-fold. These findings suggest that, in headwater catchments, permafrost has a large influence on groundwater flow and stream discharge. Increased annual air temperatures may increase groundwater discharge to streams, which has implications for ecosystem health and the long-term availability of water resources to downstream regions.

  8. Evaluating the Effects of LULC Changes and Climate Variability in the Hydrological Response of a Tropical Andean River Basin. The Case of the Boconó River Basin - Venezuela

    OpenAIRE

    Mejia Barazarte, Joel Francisco

    2012-01-01

    This research study aimed to analyze the effects of the spatial changes, particularly inherent to the LULC changes in a tropical River Basin, and its possible impact in the water resources - response. The Boconó River Basin, located in the North Venezuelan Andean Region was selected as study area, being a very representative Andean catchment in which the biophysical and the socio-cultural systems are strongly interacting to generate a quite complex dynamic reflected in the form and intensity ...

  9. Catchment Systems Engineering: A New Paradigm in Water Management

    Science.gov (United States)

    Quinn, P. F.; Wilkinson, M. E.; Burke, S.; O'Donnell, G. M.; Jonczyk, J.; Barber, N.; Nicholson, A.

    2012-04-01

    Recent catchment initiatives have highlighted the need for new holistic approaches to sustainable water management. Catchment Systems Engineering seeks to describe catchment the function (or role) as the principal driver for evaluating how it should be managed in the future. Catchment Systems Engineering does not seek to re-establish a natural system but rather works with natural processes in order to engineer landscapes to accrue multiple benefits. The approach involves quantifying and assessing catchment change, impacts and most importantly, suggests an urgent and proactive agenda for future planning. In particular, an interventionist approach to managing hydrological flow pathways across scale is proposed. It is already accepted that future management will require a range of scientific expertise and full engagement with stakeholders. This inclusive concept under a Catchment Systems Engineering agenda forces any consortia to commit to actively changing and perturbing the catchment system and thus learn, in situ, how to manage the environment for collective benefits. The shared cost, the design, the implementation, the evaluation and any subsequent modifications should involve all relevant parties in the consortia. This joint ownership of a 'hands on' interventionist agenda to catchment change is at the core of Catchment Systems Engineering. In this paper we show a range of catchment engineering projects from the UK that have addressed multi-disciplinary approaches to flooding, pollution and ecosystem management, whilst maintaining economic food production. Examples using soft engineered features such as wetlands, ponds, woody debris dams and infiltration zones will be shown. Local scale demonstration activities, led by local champions, have proven to be an effective means of encouraging wider uptake. Evidence that impacts can be achieved at local catchment scale will be introduced. Catchment Systems Engineering is a concept that relies on all relevant parties

  10. Water Yield and Sediment Yield Simulations for Teba Catchment in Spain Using SWRRB Model: Ⅰ. Model Input and Simulation Experiment

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Water yield and sediment yield in the Teba catchment, Spain, were simulated using SWRRB (Simulator for Water Resources in Rural Basins) model. The model is composed of 198 mathematical equations. About 120 items (variables) were input for the simulation, including meteorological and climatic factors, hydrologic factors, topographic factors, parent materials, soils, vegetation, human activities, etc. The simulated results involved surface runoff, subsurface runoff, sediment, peak flow, evapotranspiration, soil water, total biomass,etc. Careful and thorough input data preparation and repeated simulation experiments are the key to get the accurate results. In this work the simulation accuracy for annual water yield prediction reached to 83.68%.``

  11. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: Nutrient Application (Phosphorus and Nitrogen ) for Fertilizer and Manure Applied to Crops (Cropsplit), 2002

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the estimated amount of phosphorus and nitrogen fertilizers applied to selected crops for the year 2002, compiled for every catchment of NHDPlus for the conterminous United States. The source data set is based on 2002 fertilizer data (Ruddy and others, 2006) and tabulated by crop type per county (Alexander and others, 2007). The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy River basins, contains

  12. Attributes for NHDPlus catchments (version 1.1) for the conterminous United States: 30-year average annual maximum temperature, 1971-2000

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the 30-year (1971-2000) average annual maximum temperature in Celsius multiplied by 100 compiled for every catchment of NHDPlus for the conterminous United States. The source data were the United States Average Monthly or Annual Minimum Temperature, 1971 - 2000 raster dataset produced by the PRISM Group at Oregon State University. The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy River basins

  13. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: 30-Year Average Annual Minimum Temperature, 1971-2000

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the 30-year (1971-2000) average annual minimum temperature in Celsius multiplied by 100 compiled for every catchment of NHDPlus for the conterminous United States. The source data were the "United States Average Monthly or Annual Minimum Temperature, 1971 - 2000" raster dataset produced by the PRISM Group at Oregon State University. The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy River basins

  14. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: Mean Annual R-factor, 1971-2000

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the average annual R-factor, rainfall-runoff erosivity measure, compiled for every catchment of NHDPlus for the conterminous United States. The source data are from Christopher Daly of the Spatial Climate Analysis Service, Oregon State University, and George Taylor of the Oregon Climate Service, Oregon State University (2002), who developed spatially distributed estimates of R-factor for the period 1971-2000 for the conterminous United States. The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus

  15. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: Nutrient Inputs from Fertilizer and Manure, Nitrogen and Phosphorus (N&P), 2002

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the estimated amount of nitrogen and phosphorus in kilograms for the year 2002, compiled for every catchment of NHDPlus for the conterminous United States. The source data set is County-Level Estimates of Nutrient Inputs to the Land Surface of the Conterminous United States, 1982-2001 (Ruddy and others, 2006). The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy River basins, contains NHDPlus Production

  16. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: 30-Year Average Annual Precipitation, 1971-2000

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the 30-year (1971-2000) average annual precipitation in millimeters multiplied by 100 compiled for every catchment of NHDPlus for the conterminous United States. The source data were the "United States Average Monthly or Annual Precipitation, 1971 - 2000" raster dataset produced by the PRISM Group at Oregon State University. The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years, an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy River basins, contains

  17. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: Average Atmospheric (Wet) Deposition of Inorganic Nitrogen, 2002

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    This data set represents the average atmospheric (wet) deposition, in kilograms per square kilometer, of inorganic nitrogen for the year 2002 compiled for every catchment of NHDPlus for the conterminous United States. The source data set for wet deposition was from the USGS's raster data set atmospheric (wet) deposition of inorganic nitrogen for 2002 (Gronberg, 2005). The NHDPlus Version 1.1 is an integrated suite of application-ready geospatial datasets that incorporates many of the best features of the National Hydrography Dataset (NHD) and the National Elevation Dataset (NED). The NHDPlus includes a stream network (based on the 1:100,00-scale NHD), improved networking, naming, and value-added attributes (VAAs). NHDPlus also includes elevation-derived catchments (drainage areas) produced using a drainage enforcement technique first widely used in New England, and thus referred to as "the New England Method." This technique involves "burning in" the 1:100,000-scale NHD and when available building "walls" using the National Watershed Boundary Dataset (WBD). The resulting modified digital elevation model (HydroDEM) is used to produce hydrologic derivatives that agree with the NHD and WBD. Over the past two years (2007-2008), an interdisciplinary team from the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (USEPA), and contractors, found that this method produces the best quality NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris

  18. Stabilization of large drainage basins over geological time scales : Cenozoic West Africa, hot spot swell growth, and the Niger River

    OpenAIRE

    Chardon, Dominique; Grimaud, J. L.; Rouby, D.; BEAUVAIS, Anicet; Christophoul, F.

    2016-01-01

    Reconstructing the evolving geometry of large river catchments over geological time scales is crucial to constraining yields to sedimentary basins. In the case of Africa, it should further help deciphering the response of large cratonic sediment routing systems to Cenozoic growth of the basin-and-swell topography of the continent. Mapping of dated and regionally correlated lateritic paleolandscape remnants complemented by onshore sedimentological archives allows the reconstruction...

  19. Oxygen-18 studies of catchment runoff generation

    International Nuclear Information System (INIS)

    Understanding how runnoff is generated in catchments is important for landuse management. The authors used the response of streams to inputs of rainfall and oxygen-18 to give insight into the process of generating runoff. At Maimai, a West Coast pine forest catchment converted from native beech, streams rise to high levels very quickly after rainfall. Oxygen-18 studies have shown that most of the water discharged during a rainfall event is actually from displaced soil water not current rainfall. The authors have identified the size of this large soil water store as well as the amounts of water flowing from the macropores (with rapid release) and micropores (slow release) within the soil. In contrast, at Glendhu in tussock grassland of upland Otago, streams continue to flow strongly even when there is no rain. The authors found that more baseflow is sources from the soil B-horizon (a compact loess layer) of the surrounding hillslopes and less from the extensive headwater wetlands than was previously thought. This suggests there may be adverse effects on the baseflow if the area is forested and B-horizon water is access by trees

  20. Dominant climatic factor driving annual runoff change at catchments scale over China

    Directory of Open Access Journals (Sweden)

    Z. Huang

    2015-12-01

    Full Text Available With global climate changes intensifying, the hydrological response to climate changes has attracted more attentions. It is beneficial not only for hydrology and ecology but also for water resources planning and management to reveal the impacts of climate change on runoff. It is of great significance of climate elasticity of runoff to estimate the impacts of climatic factors on runoff. In addition, there are large spatial variations in climate type and geography characteristics over China. To get a better understanding the spatial variation of runoff response to climate variables change and detect the dominant climatic factor driving annual runoff change, we chose the climate elasticity method proposed by Yang and Yang (2011, where the impact of the catchment characteristics on runoff was represented by a parameter n. The results show that the dominant climatic factor driving annual runoff is precipitation in the most part of China, net radiation in the lower reach of Yangtze River Basin, the Pearl River Basin, the Huai River Basin and the southeast area, and wind speed in part of the northeast China.

  1. Multi-objective, multiple participant decision support for water management in the Andarax catchment, Almeria

    Science.gov (United States)

    van Cauwenbergh, N.; Pinte, D.; Tilmant, A.; Frances, I.; Pulido-Bosch, A.; Vanclooster, M.

    2008-04-01

    Water management in the Andarax river basin (Almeria, Spain) is a multi-objective, multi-participant, long-term decision-making problem that faces several challenges. Adequate water allocation needs informed decisions to meet increasing socio-economic demands while respecting the environmental integrity of this basin. Key players in the Andarax water sector include the municipality of Almeria, the irrigators involved in the intensive greenhouse agricultural sector, and booming second residences. A decision support system (DSS) is developed to rank different sustainable planning and management alternatives according to their socio-economic and environmental performance. The DSS is intimately linked to sustainability indicators and is designed through a public participation process. Indicators are linked to criteria reflecting stakeholders concerns in the 2005 field survey, such as fulfilling water demand, water price, technical and economical efficiency, social and environmental impacts. Indicators can be partly quantified after simulating the operation of the groundwater reservoir over a 20-year planning period and partly through a parallel expert evaluation process. To predict the impact of future water demand in the catchment, several development scenarios are designed to be evaluated in the DSS. The successive multi-criteria analysis of the performance indicators permits the ranking of the different management alternatives according to the multiple objectives formulated by the different sectors/participants. This allows more informed and transparent decision-making processes for the Andarax river basin, recognizing both the socio-economic and environmental dimensions of water resources management.

  2. Modeling nitrate fluxes at the catchment scale using the integrated tool CAWAQS.

    Science.gov (United States)

    Flipo, Nicolas; Even, Stéphanie; Poulin, Michel; Théry, Sylvain; Ledoux, Emmanuel

    2007-04-01

    Nitrates fluxes in the Grand Morin basin (1200 km(2)), that is subjected to intense agricultural pressure, are considered using in-stream observations (around 250 sampling days over 5 years) and physically based simulations using the CAWAQS model (CAtchment WAter Quality Simulator). In-stream nitrate concentration averaged 6 mg N L(-1), increasing by approximately 0.2 mg N L(-1) yr(-1) around this value (period 1991-1996). Our results show that, over the period of 1991-1996, the differences between in-stream observed nitrate concentrations and simulated nitrate concentrations result from nitrate losses at the basin scale. These losses are due to denitrification by transfer through wetlands, alluvial plains, the hyporheic zone, and by benthic processes in rivers. A mean annual mass balance at the basin scale indicates that 40% of the infiltration flux (3360 kg N km(-2) yr(-1)) is removed from the system via the river network, 40% is stored in aquifers and 20% is lost by denitrification (period 1991-1996). PMID:17331565

  3. Predicting community-environment relationships of stream fishes across multiple drainage basins: insights into model generality and the effect of spatial extent.

    Science.gov (United States)

    Troia, Matthew J; Gido, Keith B

    2013-10-15

    Resource managers increasingly rely on predictive models to understand species-environment relationships. Stream fish communities are influenced by longitudinal position within the stream network as well as local environmental characteristics that are constrained by catchment characteristics. Despite an abundance of studies quantifying species-environment relationships, few studies have evaluated the generality of these relationships among basins and spatial extents. We modeled community composition of stream fishes in thirteen sub-basins, nested within three basins in Kansas, USA using constrained ordination and environmental predictor variables representing (1) longitudinal network position, (2) local habitat, and (3) catchment characteristics. We tested the generality of species-environment relationships by quantifying the variation in model performance and the importance of environmental variables among the thirteen sub-basins and among three spatial extents (sub-basin, basin, state). Model performance was variable across the thirteen sub-basins, with adjusted constrained inertia ranging from 0.13 to 0.36. The importance of environmental variables was also variable among sub-basins, but longitudinal network position consistently predicted more variation in community composition than local or catchment variables. Model performance did not differ among spatial extents, but the importance of longitudinal network position decreased at broader spatial extents whereas local and catchment variables increased in importance. Results of this study support the longstanding frameworks of the river continuum and hierarchically-structured habitat. We show that (1) the relative importance of longitudinal network position, local characteristics, and catchment characteristics can vary from one region to another and (2) the spatial extent at which predictive habitat models are developed can influence the perceived importance of different environmental predictor variables

  4. GIS-Based KW-GIUH hydrological model of semiarid catchments: The case of Faria Catchment, Palestine

    International Nuclear Information System (INIS)

    Among the most basic challenges of hydrology are the quantitative understanding of the processes of runoff generation and prediction of flow hydrographs. Traditional techniques have been widely applied for the estimation of runoff hydrographs of gauged catchments using historical rainfall-runoff data and unit hydrographs. Such procedures are questioned as to their reliability and their application to ungauged, arid and semiarid catchments. To overcome such difficulties, the use of physically based rainfall-runoff process of Faria Catchment using the lately developed KW-GIUH. Faria catchment, located in the northeastern part of the West Bank, Palestine, is characterized as a semiarid region with annual rainfall depths ranging on average from 150 to 640 mm at both ends of the catchment. The Geographical Information System (GIS) techniques were used to shape the geomorphological features of the catchment. A GIS based KW-GIUH hydrological model was used to stimulate the rainfall-runoff process in the three sub-catchments of Faria, namely: Al-Badan, Al-Faria and Al-Malaqi. The simulated runoff hydrographs proved that the GIS-based KW-GIUH model is applicable to semiarid regions and can be used to estimate the unit hydrographs in the West Bank catchments. (author)

  5. A catchment-wide assessment of bed sediment metal concentrations in the first industrial city

    Science.gov (United States)

    Hurley, Rachel; Rothwell, James; Woodward, Jamie

    2016-04-01

    Manchester is often heralded as the 'first industrial city'. Rapid industrialisation in the 18th and 19th centuries saw vast quantities of fine-grained sediments (e.g. boiler ash and cinders) and contaminants (e.g. dyes, bleaches, and chemicals) deposited into the river channels of the Irwell and Mersey in a manner largely unchecked until the 1970s. Although water quality has improved in recent decades, there is a paucity of information on fluvial sediment quality and the extent to which a legacy of historical contamination persists in the contemporary river network. Forty five sites were sampled across the Irwell and Mersey catchments during low flow conditions in spring/summer 2015. Fine-grained bed sediment was collected using the Lambert and Walling (1988) method. Wet sieving was used to isolate the <63 μm fraction for geochemical analysis. Heavy metal concentrations were obtained via XRF with a particular focus on As, Cr, Cu, Pb and Zn. In order to explore controls on sediment-associated metal concentrations, additional characteristics of the bed sediment were also investigated, including particle size and organic matter content. Enrichment factors, based on mean concentrations obtained from pre-industrial floodplain deposits, were calculated. The enrichment factors reveal severe or very severe metal contamination across the whole catchment, including the headwater basins. Relationships between bed sediment quality and hotspots of historic industrial activity have been examined - these reveal complex spatial patterns associated with the high number and variety of historic contaminant inputs. These data form the first baseline assessment and will be used within a larger project investigating the impact of extreme hydrological events on bed sediment quality and transfer in these catchments.

  6. Nitrogen budget of Lago Maggiore: the relative importance of atmospheric deposition and catchment sources

    Directory of Open Access Journals (Sweden)

    Gabriele TARTARI

    2001-02-01

    Full Text Available Hydrological and chemical data of 1996 and 1997 are used to evaluate the relative contributions of atmospheric deposition and urban/industrial wastewaters to the nitrogen budget of Lago Maggiore. The atmospheric load of nitrogen was about 80% of the total input to the lake, with negligible variations in dry (1997 and wet (1996 years. A comparison of the two study years with the yearly N budgets evaluated from 1978 to 1998, showed that the N load was higher with increasing amounts of precipitation/water inflow. Soils and vegetation act as N sinks; the % retention varies between 40-60% for the forested catchments with low population density in the central-northern part of the basin, to values close to zero or even negative in the south, indicating a net leaching from the soils. The Traaen & Stoddard (1995 approach revealed that all the catchments of the major inflowing rivers were oversaturated with nitrogen. The long-term trend of nitrogen concentrations in Lago Maggiore (1955-99 is analogous to the trend for atmospheric deposition (1975-99, which is related to emissions of nitrogen oxides and ammonia in the atmosphere. The relationships between the present N load and in-lake concentrations are discussed using a budget model, which is also used to infer the pristine load of N. The close relationships between N trends in lakes Maggiore, Como and Iseo, and the geographical and anthropogenic features common to their catchments, suggest that the results obtained for Lago Maggiore can be extended to a wider area.

  7. Analysis of models assessing the radionuclide migration from catchments to water bodies

    International Nuclear Information System (INIS)

    In this paper the analysis of models for assessing the migration of radioactive substances from catchments to water bodies was carried out. Comparisons are made between the mathematical form of the experimental dissolved radionuclide transfer functions (Transfer Function = the amount of radionuclide flowing per unit time from upstream drainage basin to a water body following a single-pulse deposition of radioactive substance) evaluated for rivers in Europe contaminated after the Chernobyl accident, with the open-quotes Green Functionsclose quotes (Green Function = the radionuclide flow per unit time from catchment to water body calculated by the model as a result of a single-pulse input deposition) characterizing some of the most common models. Generally transfer functions are the sum of some time-dependent exponential components. The analysis showed that two main components (a short-term and a long-term component) may be detected over a period of only a few years after the accident. The comparison of transfer functions and Green functions showed that (1) models based on the traditional concept of kd (the radionuclide partition coefficient soil-water) do not explain the higher value of the experimental long-term effective-decay constant for 137Cs compared with 90Sr; and (2) traditional models do not explain the nonlinear dependence of the flux (Bq s-1) of dissolved 90Sr migrating through a catchment as a function of the water flux. A semi-empirical model was developed to give reason for the above effects. This model is based on phenomena of water saturation in different soil layers and on the nonreversible processes responsible for the non-availability to migration of radionuclides. 12 refs., 4 figs., 7 tabs

  8. How relevant is the interannual vegetation's dynamic in the water cycle at catchment scale?

    Science.gov (United States)

    Echeverría Martinez, Carlos Antonio; Ruiz-Pérez, Guiomar; Francés, Félix

    2016-04-01

    To effectively analyse a portion of the Earth's surface from a hydrological perspective, it is important to understand that water cycle and vegetation dynamics are strongly connected. Vegetation holds an important role in land surface water balance, in particular considering that vegetation physiology and spatial parameters are dynamic in time. A traditional hydrological model considerates vegetation as a static parameter through years, representing very well observed streamflow. Nowadays, the tendency is to include the vegetation as a state variable. In this way, we obtain a better simulation of both, blue water and green water, as well as the ratio between them. Applying the hydrological distributed model TETIS, this work presents the comparison of considering static vegetation or dynamics vegetation. The study catchment was characterized by a good availability of input data in the analysis period (from 1990 to 2011) and it is mainly covered by forested areas. The selected basin is the upper part of the Turia River, up to the Benageber Reservoir, analyzing if is relevant to use dynamics vegetation instead of static vegetation for the water resources evaluation in semiarid Mediterranean catchments. Both model variations were applied in three different scenarios: a dry year, a normal year and a wet year. In each scenario the model was applied considering both static vegetation and vegetation dynamics. At the catchment scale, considering vegetation as an stationary parameter both, green water and the ratio between blue and green water, were underestimated. Consequently, not considering the vegetation's dynamic in semiarid conditions can produce the underestimation of the amount of green water, which introduces a higher uncertainty in the resulting water balance in present conditions but also in future climate change scenarios.

  9. Pursuing realistic hydrologic model under SUPERFLEX framework in a semi-humid catchment in China

    Science.gov (United States)

    Wei, Lingna; Savenije, Hubert H. G.; Gao, Hongkai; Chen, Xi

    2016-04-01

    Model realism is pursued perpetually by hydrologists for flood and drought prediction, integrated water resources management and decision support of water security. "Physical-based" distributed hydrologic models are speedily developed but they also encounter unneglectable challenges, for instance, computational time with low efficiency and parameters uncertainty. This study step-wisely tested four conceptual hydrologic models under the framework of SUPERFLEX in a small semi-humid catchment in southern Huai River basin of China. The original lumped FLEXL has hypothesized model structure of four reservoirs to represent canopy interception, unsaturated zone, subsurface flow of fast and slow components and base flow storage. Considering the uneven rainfall in space, the second model (FLEXD) is developed with same parameter set for different rain gauge controlling units. To reveal the effect of topography, terrain descriptor of height above the nearest drainage (HAND) combined with slope is applied to classify the experimental catchment into two landscapes. Then the third one (FLEXTOPO) builds different model blocks in consideration of the dominant hydrologic process corresponding to the topographical condition. The fourth one named FLEXTOPOD integrating the parallel framework of FLEXTOPO in four controlled units is designed to interpret spatial variability of rainfall patterns and topographic features. Through pairwise comparison, our results suggest that: (1) semi-distributed models (FLEXD and FLEXTOPOD) taking precipitation spatial heterogeneity into account has improved model performance with parsimonious parameter set, and (2) hydrologic model architecture with flexibility to reflect perceived dominant hydrologic processes can include the local terrain circumstances for each landscape. Hence, the modeling actions are coincided with the catchment behaviour and close to the "reality". The presented methodology is regarding hydrologic model as a tool to test our

  10. Anatomy of a catchment: the relation of physical attributes of the Plynlimon catchments to variations in hydrology and water status

    Directory of Open Access Journals (Sweden)

    C. Brandt

    2004-01-01

    Full Text Available The Plynlimon headwater catchments in mid-Wales have been a landmark study of water resources in the UK uplands for over 30 years. The main physical features of the catchments have been digitised as the basis for linking new model developments and process understanding. Examples are given of how the main physical attributes are related to land management, hydrology and water quality. These data are also being used to provide insights into catchment processes that may underpin the development of new research. This work is particularly relevant given the need for the assessment of water status under the Water Framework Directive. The paper presents hypothetical management scenarios for the catchments, to show how ecological status may be improved, for example, by selectively restructuring areas of commercial forest. Keywords: Plynlimon, GIS, catchment study, forestry, hydrology, WFD

  11. Comparative assessment of spatiotemporal snow cover changes and hydrological behavior of the Gilgit, Astore and Hunza River basins (Hindukush-Karakoram-Himalaya region, Pakistan)

    Science.gov (United States)

    Tahir, Adnan Ahmad; Adamowski, Jan Franklin; Chevallier, Pierre; Haq, Ayaz Ul; Terzago, Silvia

    2016-03-01

    The Upper Indus Basin (UIB), situated in the Himalaya-Karakoram-Hindukush (HKH) mountain ranges, is the major contributor to the supply of water for irrigation in Pakistan. Improved management of downstream water resources requires studying and comparing spatiotemporal changes in the snow cover and hydrological behavior of the river basins located in the HKH region. This study explored in detail the recent changes that have occurred in the Gilgit River basin (12,656 km2; western sub-basin of UIB), which is characterized by a mean catchment elevation of 4250 m above sea level (m ASL). The basin's snow cover was monitored through the snow products provided by the MODIS satellite sensor, while analysis of its hydrological regime was supported by hydrological and climatic data recorded at different altitudes. The Gilgit basin findings were compared to those previously obtained for the lower-altitude Astore basin (mean catchment elevation = 4100 m ASL) and the higher-altitude Hunza basin (mean catchment elevation = 4650 m ASL). These three catchments were selected because of their different glacier coverage, contrasting area distribution at high altitudes and significant impact on the Upper Indus River flow. Almost 7, 5 and 33 % of the area of the Gilgit, Astore and Hunza basins, respectively, are situated above 5000 m ASL, and approximately 8, 6 and 25 %, respectively, are covered by glaciers. The UIB region was found to follow a stable or slightly increasing trend in snow coverage and had a discharge dominated by snow and glacier melt in its western (Hindukush-Karakoram), southern (Western-Himalaya) and northern (Central-Karakoram) sub-basins.

  12. 水利工程对河网连通性的影响研究——以太湖西苕溪流域为例%Study on impacts from water conservancy projects on river network connectivity——a case of Xizhaoxi River Sub-catchment of Taihu Lake Basin

    Institute of Scientific and Technical Information of China (English)

    罗贤; 许有鹏; 徐光来; 余铭婧

    2012-01-01

    The connectivity of river network plays an important role in maintaining the structure and function of river ecosystem. However, the water conservancy project can change the connectivity of natural river network and directly endanger the stability and health of river ecosystem. Based on the methods such as spatial analysis, continuity index, Dendritic Connectivity Index( DCI) , etc. , the impacts from sluices and dams on the connectivity of river network are deeply discussed herein. The result shows that with the Dendritic Connectivity Index( DCI) , more overall analysis can be made on the impacts from the sluices and dams on various geographic locations with various amounts and connectivities. Therefore, this method can be widely applied to the comparison of different alternatives during planning of river basins and then provide a reference for the site selection and design of the water conservancy project and facility concerned.%河网连通性对维护河流生态系统的结构和功能具有重要作用,水利工程可改变天然河网的连通性,直接威胁到河流生态系统的健康与稳定.利用空间分析、连续性指标以及树状河网连通性指数等方法,深入探讨了闸坝对河网连通性的影响.结果表明,树状河网连通性指数能够较为全面地分析不同数量、可通过性及地理位置的闸坝对河网连通性的影响,可以广泛应用于流域规划过程中不同方案的比较,从而为水利工程设施的选址及设计提供参考.

  13. BISTRIŢA ARDELEANĂ CATCHMENT AREA – COORDINATES OF STRATEGIC LAND MANAGEMENT

    Directory of Open Access Journals (Sweden)

    S. F. FONOGEA

    2014-11-01

    Full Text Available Bistriţa Ardeleană Catchment Area – Coordinates of Strategic Land Management. The approach of “creation and execution” / designing of this territorial cut-out of basin type, in the paradigmatic context of the durable development, is subordinate to an (almostexhaustive investigation of the vocation and potentiality of this area in terms of geographical and spatial organization of the territory. There may be multiple reasons to justify the existence of a paper which approaches this territory in an integrating and prospective manner. First of all, this area has an “identity card” type of evidence, at the level of the collective memory of the county’s inhabitants. Even if many contradictions multiplied along the years, nuances and specificities have been imposed, there is a filiation and a common territorial manifestation for the population and the settlements in this area. Secondly, the building of the settlements from Bârgău area and their later historical evolution was accomplished in a close interdependence, therefore the premise of development cannot be achieved outside the association (the access to different financing sources is easier when partnerships are built. Thirdly, the challenge of developing a study that shows the real prospects of developing a territory from the Bistriţa Ardeleană catchment area was motivated by subjective arguments, and the love of nature and environment played a key role in the effort to complete this action.

  14. Catchment- and reach-scale controls on the distribution and expectation of geomorphic channel adjustment

    Science.gov (United States)

    Lisenby, Peyton E.; Fryirs, Kirstie A.

    2016-05-01

    Variability in channel function (behavior) can be assessed by characterizing different forms of adjustment over time. Here, historical channel adjustments in three tributary systems of the Lockyer Valley, Southeast Queensland (SEQ) are analyzed in order to evaluate the range of catchment- and reach-scale controls on channel behavior. Over 300 individual adjustments and 13 forms of adjustment were identified over a ˜130 year time span. We measured the width-to-depth ratio (W:D), mean stream power (ω), and basin area (A) at the location of all observed adjustments. The most common forms of adjustment were avulsions, lateral expansion of the channel, and bend adjustments. The tributary systems behave distinctly different from one another according to statistical comparisons between the W:D, ω, and A data for these forms of adjustment. We find that it is possible to develop process domains or typologies for forms of geomorphic adjustment found in the Lockyer Valley. These domains or typologies provide the foundations for synoptic comparisons between catchments and assessing the expectation of channel adjustment (forecasting), which should be included in process-based river management practice.

  15. Application of ANN and fuzzy logic algorithms for streamflow modelling of Savitri catchment

    Indian Academy of Sciences (India)

    Mahesh Kothari; K D Gharde

    2015-07-01

    The streamflow prediction is an essentially important aspect of any watershed modelling. The black box models (soft computing techniques) have proven to be an efficient alternative to physical (traditional) methods for simulating streamflow and sediment yield of the catchments. The present study focusses on development of models using ANN and fuzzy logic (FL) algorithm for predicting the streamflow for catchment of Savitri River Basin. The input vector to these models were daily rainfall, mean daily evaporation, mean daily temperature and lag streamflow used. In the present study, 20 years (1992–2011) rainfall and other hydrological data were considered, of which 13 years (1992–2004) was for training and rest 7 years (2005–2011) for validation of the models. The mode performance was evaluated by R, RMSE, EV, CE, and MAD statistical parameters. It was found that, ANN model performance improved with increasing input vectors. The results with fuzzy logic models predict the streamflow with single input as rainfall better in comparison to multiple input vectors. While comparing both ANN and FL algorithms for prediction of streamflow, ANN model performance is quite superior.

  16. Catchments as simple dynamical systems: A case study on methods and data requirements for parameter identification

    Science.gov (United States)

    Melsen, L. A.; Teuling, A. J.; Berkum, S. W.; Torfs, P. J. J. F.; Uijlenhoet, R.

    2014-07-01

    In many rainfall-runoff models, at least some calibration of model parameters has to take place. Especially for ungauged or poorly gauged basins this can be problematic, because there is little or no data available for calibration. A possible solution to overcome the problems caused by data scarcity is to set up a measurement campaign for a limited time period. In this study, we determine the minimum amount of data required to determine robust parameter values for a simple model with two parameters. The model is constructed such that the parameters can be determined not only with automatic calibration, but also by recession analysis and a priori from Boussinesq theory. The model has been applied to a research catchment in Switzerland. For automatic calibration and recession analysis, one season (5 months) is found to be sufficient to give robust parameters for simulation of high flows over the full observation period. For automatic calibration, this should be the season with the highest precipitation, for recession analysis the season with least evapotranspiration. The Boussinesq equation is able to give good parameter estimates for modeling high flows, but detailed in situ knowledge of the catchment is required. Automatic calibration outperforms recession analysis and Boussinesq theory by far when it comes to parameter estimation with a focus on prediction of low flows. It was shown that a single set of parameters cannot simultaneously describe high and low flows with a reasonable accuracy, suggesting that more than two parameters are needed to characterize subsurface properties.

  17. Ecohydrological evolution in the catchment of Lake Druksiai, Lithuania, under anthropogenic pressure

    International Nuclear Information System (INIS)

    The catchment area of Lake Druksiai (the Ignalina Nuclear Power Plant cooling basin) is exposed to severe anthropogenic pressures due to urbanization, industrialization and, to a smaller scale, to agricultural development. Ecological changes in the lake are investigated in connection with the water balance of Lake Druksiai and the interaction of surface water and groundwater in the catchment. The main sources which contribute to the most active water exchange in the lake are total surface runoff, precipitation and artificial circulation of water used in the cooling system of the reactor turbine condensers of the Ignalina NPP. According to the observation and model results, natural groundwater flow does not influence significantly the water exchange in the lake. However, groundwater, particularly of the confined Upper-Middle Devonian aquifer, is the basic source of centralized water supply in the region and indirectly has become the most significant chain of nutrient transport to the lake. Due to this impact, the trophic state of the lake has changed from (oligo)mesotrophic to almost eutrophic within twenty years of operation of the Ignalina NPP. The increase of the water surface temperature and alteration of vertical thermal stratification have stimulated the main ecological changes in Lake Druksiai. (author)

  18. Vulnerability of groundwater resources to interaction with river water in a boreal catchment

    Directory of Open Access Journals (Sweden)

    A. Rautio

    2015-02-01

    Full Text Available A low altitude aerial infrared (AIR survey was conducted to identify hydraulic connections between aquifers and rivers, and to map spatial surface temperature patterns along boreal rivers. In addition, the stable isotopic compositions (δ18O, δD, dissolved silica (DSi concentrations and electrical conductivity of water in combination with AIR data were used as tracers to verify the observed groundwater discharge into the river system in a boreal catchment. The results of AIR surveys and hydrogeochemical studies performed in the boreal catchment are presented. Based on low temperature anomalies in the AIR survey, around 370 groundwater–surface water interaction sites were located along the main river channel and its tributaries (203 km altogether. On the basis of AIR survey, the longitudinal temperature patterns of the studied rivers differed noticeably. The stable isotopes and DSi composition revealed major differences between the studied rivers. The interaction locations identified in the proximity of 12 municipal water intake plants during the low-flow seasons should be considered as potential risk areas for water intake plants during flood periods (groundwater quality deterioration due to bank infiltration, and should be taken under consideration in river basin management under changing climatic situations.

  19. Application of ANN and fuzzy logic algorithms for streamflow modelling of Savitri catchment

    Science.gov (United States)

    Kothari, Mahesh; Gharde, K. D.

    2015-07-01

    The streamflow prediction is an essentially important aspect of any watershed modelling. The black box models (soft computing techniques) have proven to be an efficient alternative to physical (traditional) methods for simulating streamflow and sediment yield of the catchments. The present study focusses on development of models using ANN and fuzzy logic (FL) algorithm for predicting the streamflow for catchment of Savitri River Basin. The input vector to these models were daily rainfall, mean daily evaporation, mean daily temperature and lag streamflow used. In the present study, 20 years (1992-2011) rainfall and other hydrological data were considered, of which 13 years (1992-2004) was for training and rest 7 years (2005-2011) for validation of the models. The mode performance was evaluated by R, RMSE, EV, CE, and MAD statistical parameters. It was found that, ANN model performance improved with increasing input vectors. The results with fuzzy logic models predict the streamflow with single input as rainfall better in comparison to multiple input vectors. While comparing both ANN and FL algorithms for prediction of streamflow, ANN model performance is quite superior.

  20. A physically-based parsimonious hydrological model for flash floods in Mediterranean catchments

    Directory of Open Access Journals (Sweden)

    H. Roux

    2011-09-01

    Full Text Available A spatially distributed hydrological model, dedicated to flood simulation, is developed on the basis of physical process representation (infiltration, overland flow, channel routing. Estimation of model parameters requires data concerning topography, soil properties, vegetation and land use. Four parameters are calibrated for the entire catchment using one flood event. Model sensitivity to individual parameters is assessed using Monte-Carlo simulations. Results of this sensitivity analysis with a criterion based on the Nash efficiency coefficient and the error of peak time and runoff are used to calibrate the model. This procedure is tested on the Gardon d'Anduze catchment, located in the Mediterranean zone of southern France. A first validation is conducted using three flood events with different hydrometeorological characteristics. This sensitivity analysis along with validation tests illustrates the predictive capability of the model and points out the possible improvements on the model's structure and parameterization for flash flood forecasting, especially in ungauged basins. Concerning the model structure, results show that water transfer through the subsurface zone also contributes to the hydrograph response to an extreme event, especially during the recession period. Maps of soil saturation emphasize the impact of rainfall and soil properties variability on these dynamics. Adding a subsurface flow component in the simulation also greatly impacts the spatial distribution of soil saturation and shows the importance of the drainage network. Measures of such distributed variables would help discriminating between different possible model structures.

  1. The Territory of the Tisa Catchment Area between Natural and Functional Organization

    Directory of Open Access Journals (Sweden)

    POMPEI COCEAN

    2010-01-01

    Full Text Available The TICAD project is in essence a symbiosis between what natural organization of the territory through the agency of catchment areas means and its anthropogenic organization having growth poles and gravity axes as pillars. The analysis highlights the historically-exemplified difficulties in correlating the two forms of organization and the factors that caused them. An increase of the index of spatial overlapping and functional imbrication between them can be noticed with the approach of lower hydrographic taxa (collectors, 1st to 3rd rank tributaries and regional taxa (region, county, microregion, commune, a genuine identification often appearing for the basal ones. The new geopolitical circumstances, induced by the creation and enlargement of the European Union, represent a catalyst for the organisation of the Tisa river basin in the light of the new concepts of economic, cultural or environmental cross-border collaboration.

  2. Future climate scenarios and rainfall--runoff modelling in the Upper Gallego catchment (Spain).

    Science.gov (United States)

    Bürger, C M; Kolditz, O; Fowler, H J; Blenkinsop, S

    2007-08-01

    Global climate change may have large impacts on water supplies, drought or flood frequencies and magnitudes in local and regional hydrologic systems. Water authorities therefore rely on computer models for quantitative impact prediction. In this study we present kernel-based learning machine river flow models for the Upper Gallego catchment of the Ebro basin. Different learning machines were calibrated using daily gauge data. The models posed two major challenges: (1) estimation of the rainfall-runoff transfer function from the available time series is complicated by anthropogenic regulation and mountainous terrain and (2) the river flow model is weak when only climate data are used, but additional antecedent flow data seemed to lead to delayed peak flow estimation. These types of models, together with the presented downscaled climate scenarios, can be used for climate change impact assessment in the Gallego, which is important for the future management of the system. PMID:17428594

  3. The Effect of Converting Combined Sewer Catchments to Separate Sewer Catchments

    DEFF Research Database (Denmark)

    Schaarup-Jensen, Kjeld; Rasmussen, Michael R.; Thorndahl, Søren Liedtke

    2011-01-01

    separate sewer catchments decreases the amounts of storm water and pollutants diverted to the waste water treatment plant (WWTP) or as combined sewer overflows (CSO). But this happens at the expense of an increase in amounts of storm water and pollutants diverted to local receiving waters when detention......The overall objective of this paper is to contribute to the standing debate concerning the advantages of separate sewer systems compared to traditional combined sewers. By a case study this investigation reveals that a transformation of one fourth of a given total area from being combined to become...... ponds are not built-in the new separate sewer systems. If a total catchment area transformation – instead of only one fourth – is put through, the consequences could be fatal for receiving waters if no retention of pollutants is integrated in such a transformation....

  4. Catchments as simple dynamical systems: Experience from a Swiss prealpine catchment

    OpenAIRE

    Teuling, A.J.; Lehner, I.; J. W. Kirchner; Seneviratne, S. I.

    2010-01-01

    Heterogeneity in small-scale subsurface flow processes does not necessarily lead to complex system behavior at larger scales. Here we use the simple dynamical systems approach recently proposed by Kirchner (WRR, 2009) to analyze, characterize, and simulate streamflow dynamics in the Swiss Rietholzbach catchment. The Rietholzbach data set used here provides 32 years of continuous and high-quality observations, which include a soil moisture profile and unique observations of storage changes and...

  5. The application of GEOtop for catchment scale hydrology in Ireland

    Science.gov (United States)

    Lewis, C.; Xu, X.; Albertson, J.; Kiely, G.

    2009-04-01

    GEOtop represents the new generation of distributed hydrological model driven by geospatial data (e.g. topography, soils, vegetation, land cover). It estimates rainfall-runoff, evapotranspiration and provides spatially distributed outputs as well as routing water and sediment flows through stream and river networks. The original version of GEOtop designed in Italy, includes a rigorous treatment of the core hydrological processes (e.g. unsaturated and saturated flow and transport, surface energy balances, and streamflow generation/routing). Recently GEOtop was extended to include treatment of shallow landslides. The GEOtop model is built on an open-source programming framework, which makes it well suited for adaptation and extension. GEOtop has been run very successfully in a number of alpine catchments (such as Brenta) but has not been used on Irish catchments before. The cell size used for the spatially distributed inputs varies from catchment to catchment. In smaller catchments (less than 2000ha) 50 by 50m cells have been used and 200 by 200 for larger catchments. Smaller cell sizes have been found to significantly increase the computational time so a larger cell size is used providing it does not significantly affect the performance of the model. Digital elevation model, drainage direction, landuse and soil type maps are the minimum spatial requirements with precipitation, radiation, temperature, atmospheric pressure and wind speed been the minimum meteorological requirements for a successful run. The soil type maps must also contain information regarding texture and hydraulic conductivity. The first trial of GEOtop in Ireland was on a small 1524 ha catchment in the south of Ireland. The catchment ranges from 50 to just over 200m, the land use is predominately agricultural grassland and it receives on average 1400mm of rain per year. Within this catchment there is a meteorological tower which provides the meteorological inputs, soil moisture is also recorded at

  6. Comparison of drought occurrence in selected Slovak and Czech catchments

    Science.gov (United States)

    Fendekova, Miriam; Fendek, Marian; Porubska, Diana; Hanel, Martin; Horacek, Stanislav; Martinkova, Marta; Vizina, Adam

    2014-05-01

    The presented study is focused on the analysis and comparison of hydrological drought occurrence, development and duration in six small to middle sized catchments in the Czech Republic (CZ) and Slovakia. The main questions to be answered are: (1) are there correlations between the physical conditions in the catchments and drought occurrence, and (2) does the spatial trend of drought occurrence exist. The Žitava catchment is located in the central western part of Slovakia having runoff dominated by rainfall with the contribution of snow melting during the spring period. The Belá River catchment is located on the contact of Západné and Vysoké Tatry Mts. in the north of Slovakia. The runoff is snow to snow-rain combined type. The Ľupčianka catchment is located on the northern slopes of the Nízke Tatry Mts. in the northern part of the central Slovakia. The runoff regime is snow-rain combined in the upper part of the catchment, and of rain-snow type in the rest of catchment. The Rakovnický potok brook (CZ) has its spring in Rakovnická pahorkatina hilly land. Runoff is dominated by rainfall, quite heavily influenced by water uptakes in the catchment. The Teplá River (CZ) originates in peat meadows in the western part of the Czech Republic. Runoff is dominated by rainfall. The Metuje catchment (CZ) is formed by Adršsbach-Teplické stěny Upland. The headwater part is typical by deeply incest valleys, table mountains and pseudokarst caves. The discharge is fed dominantly by groundwater. The streamflow drought was characterized using discharge data, the groundwater drought using the base flow values. The local minimum method was used for base flow separation. The threshold level method (Q80, BF80) and the sequent peak algorithm were used for calculation of drought duration in discharge and base flow time series. The data of the same three decades of the common period (1971 - 1980, 1981 - 1990 and 1991 - 2000) were used. The resulting base flow values along with

  7. Usefulness of four hydrological models in simulating high-resolution discharge dynamics of a catchment adjacent to a road

    Directory of Open Access Journals (Sweden)

    Z. Kalantari

    2012-04-01

    Full Text Available Four hydrological models (LISEM, MIKE SHE, CoupModel and HBV were compared with respect to their capability to predict peak flow in a small catchment upstream of a road in SE Norway on an hourly basis. All four models were calibrated using hourly observed streamflow. Simulated and observed discharge generated during three types of hydrological situations characteristic of winter/spring conditions causing overland flow were considered: snowmelt, partially frozen soil and heavy rain events. Using parameter sets optimised for winter/spring conditions, flows simulated by HBV coupled with CoupModel were comparable to measured discharge from the catchment in corresponding periods. However, this combination was best when all the parameters were calibrated in HBV. For ungauged basins with no real-time monitoring of discharge and when the spatial distribution is important, MIKE SHE may be more suitable than the other models, but the lack of detailed input data and the uncertainty in physical parameters should be considered. LISEM is potentially capable of calculating runoff from small catchments during winter/spring but requires better description of snowmelt, infiltration into frozen layers and tile drainage. From a practical road maintenance perspective, the usefulness and accuracy of a model depends on its ability to represent site-specific processes, data availability and calibration requirements.

  8. Recent trends in water quality in an agricultural catchment in Eastern Scotland: elucidating the roles of hydrology and land use.

    Science.gov (United States)

    Dunn, S M; Sample, J; Potts, J; Abel, C; Cook, Y; Taylor, C; Vinten, A J A

    2014-07-01

    Across the EU, programmes of measures have been introduced as part of river basin management planning as a means of tackling problems of diffuse pollution from agriculture. Evidence is required to demonstrate the effectiveness of these measures and with this overarching objective, monitoring of an agricultural catchment in Eastern Scotland was initiated in 2007. As a precursor to evaluating the effect of new management measures it is essential to understand how other factors, including hydrology and land use changes, could have influenced water quality. This study undertook an analysis of the trends in concentrations and loads of nitrate, soluble reactive phosphorus (SRP), suspended solids (SS) and turbidity measured at six points in the catchment over a six year period. The results identified both differing trends between determinands and differing trends occurring over varying spatial scales. The only direct relationships between land use and water quality that could be identified based on annual data was a positive link between arable cropping and nitrate concentrations. At the sub-catchment scale some temporal changes in land use and management explained short-term trends in nitrate but not in SRP. Lags in the system were identified due to soil adsorption, in-stream/loch processing and groundwater transport making the identification of cause and effect problematic. The results have implications for the demonstration of effectiveness of measures over the shorter term and the timescales of recovery from diffuse pollution. Longer term monitoring at small scales will be important in this regard. PMID:24718675

  9. Change of the radionuclide content of landscapes contamination in the small catchment at the Bryansk-Belarus caesium spot

    International Nuclear Information System (INIS)

    The results of the joint Russian-Belarus RFBR-BelRFBR project no. 02-05-81011 will be shown. Information on the spatial redistribution of 137Cs within small catchment and through the connected landscapes is an important background for estimating consequences of the Chernobyl contamination. 137Cs can be used as a tracer for study the direction and intensity of geo-chemical processes in landscapes of small catchment. The experimental data on the modern radionuclide content of soil and plant contamination have been received at the expeditions of 2000-2004 in the regions situated on distances 50, 150 and 250 km from the Chernobyl NPP on territories of Belarus and Russia. Some small catchment in the Dnieper basin have been studied (Braginka, Sozh and Moskovka rivers). The content of 137Cs, 90Sr, 239+240Pu and 241Am in soils will be presented. The modern variability of contamination levels in each of connected landscapes will be compared with the variability estimated immediately after the Chernobyl accident. The high spatial fixation of Caesium spots by the Polessye landscapes will be shown. (author)

  10. Spatial characterization of catchment dispersion mechanisms in an urban context

    Science.gov (United States)

    Rossel, Florian; Gironás, Jorge; Mejía, Alfonso; Rinaldo, Andrea; Rodriguez, Fabrice

    2014-12-01

    Previous studies have examined in-depth the dispersion mechanisms in natural catchments. In contrast, these dispersion mechanisms have been studied little in urban catchments, where artificial transport elements and morphological arrangements are expected to modify travel times and mobilize excess rainfall from spatially distributed impervious sites. This has the ability to modify the variance of the catchment's travel times and hence the total dispersion. This work quantifies the dispersion mechanisms in an urban catchment using the theory of transport by travel times as represented by the Urban Morpho-climatic Instantaneous Unit Hydrograph (U-McIUH) model. The U-McIUH computes travel times based on kinematic wave theory and accounts explicitly for the path heterogeneities and altered connectivity patterns characteristic of an urban drainage network. The analysis is illustrated using the Aubinière urban catchment in France as a case study. We found that kinematic dispersion is dominant for small rainfall intensities, whereas geomorphologic dispersion becomes more dominant for larger intensities. The total dispersion scales with the drainage area in a power law fashion. The kinematic dispersion is dominant across spatial scales up to a threshold of approximately 2-3 km2, after which the geomorphologic dispersion becomes more dominant. Overall, overland flow is responsible for most of the dispersion in the catchment, while conduits tend to counteract the increase of the geomorphologic dispersion with a negative kinematic dispersion. Further study with other catchments is needed to asses if the latter is a general feature of urban drainage networks.

  11. Subsurface storage capacity influences climate-evapotranspiration interactions in three western United States catchments

    Science.gov (United States)

    Garcia, E. S.; Tague, C. L.

    2015-12-01

    In the winter-wet, summer-dry forests of the western United States, total annual evapotranspiration (ET) varies with precipitation and temperature. Geologically mediated drainage and storage properties, however, may strongly influence these relationships between climate and ET. We use a physically based process model to evaluate how plant accessible water storage capacity (AWC) and rates of drainage influence model estimates of ET-climate relationships for three snow-dominated, mountainous catchments with differing precipitation regimes. Model estimates show that total annual precipitation is a primary control on inter-annual variation in ET across all catchments and that the timing of recharge is a second-order control. Low AWC, however, increases the sensitivity of annual ET to these climate drivers by 3 to 5 times in our two study basins with drier summers. ET-climate relationships in our Colorado basin receiving summer precipitation are more stable across subsurface drainage and storage characteristics. Climate driver-ET relationships are most sensitive to subsurface storage (AWC) and drainage parameters related to lateral redistribution in the relatively dry Sierra site that receives little summer precipitation. Our results demonstrate that uncertainty in geophysically mediated storage and drainage properties can strongly influence model estimates of watershed-scale ET responses to climate variation and climate change. This sensitivity to uncertainty in geophysical properties is particularly true for sites receiving little summer precipitation. A parallel interpretation of this parameter sensitivity is that spatial variation in storage and drainage properties are likely to lead to substantial within-watershed plot-scale differences in forest water use and drought stress.

  12. Hydrological and sedimentation implications of landscape changes in a Himalayan catchment due to bioenergy cropping

    Science.gov (United States)

    Remesan, Renji; Holman, Ian; Janes, Victoria

    2015-04-01

    There is a global effort to focus on the development of bioenergy and energy cropping, due to the generally increasing demand for crude oil, high oil price volatility and climate change mitigation challenges. Second generation energy cropping is expected to increase greatly in India as the Government of India has recently approved a national policy of 20 % biofuel blending by 2017; furthermore, the country's biomass based power generation potential is estimated as around ~24GW and large investments are expected in coming years to increase installed capacity. In this study, we have modelled the environmental influences (e.g.: hydrology and sediment) of scenarios of increased biodiesel cropping (Jatropha curcas) using the Soil and Water Assessment Tool (SWAT) in a northern Indian river basin. SWAT has been applied to the River Beas basin, using daily Tropical Rainfall Measuring Mission (TRMM) precipitation and NCEP Climate Forecast System Reanalysis (CFSR) meteorological data to simulate the river regime and crop yields. We have applied Sequential Uncertainty Fitting Ver. 2 (SUFI-2) to quantify the parameter uncertainty of the stream flow modelling. The model evaluation statistics for daily river flows at the Jwalamukhi and Pong gauges show good agreement with measured flows (Nash Sutcliffe efficiency of 0.70 and PBIAS of 7.54 %). The study has applied two land use change scenarios of (1) increased bioenergy cropping in marginal (grazing) lands in the lower and middle regions of catchment (2) increased bioenergy cropping in low yielding areas of row crops in the lower and middle regions of the catchment. The presentation will describe the improved understanding of the hydrological, erosion and sediment delivery and food production impacts arising from the introduction of a new cropping variety to a marginal area; and illustrate the potential prospects of bioenergy production in Himalayan valleys.

  13. Soil storage influences climate-evapotranspiration interactions in three western United States catchments

    Science.gov (United States)

    Garcia, E. S.; Tague, C. L.

    2015-08-01

    In the winter-wet, summer-dry forests of the western United States, total annual evapotranspiration (ET) varies with precipitation and temperature. Geologically mediated drainage and storage properties, however, may strongly influence these relationships between climate and ET. We use a physically based process model to evaluate how soil available water capacity (AWC) and rates of drainage influence model estimates of ET-climate relationships for three snow-dominated, mountainous catchments with differing precipitation regimes. Model estimates show that total annual precipitation is a primary control on inter-annual variation in ET across all catchments and that the timing of recharge is a second order control. Low soil AWC, however, increases the sensitivity of annual ET to these climate drivers by three to five times in our two study basins with drier summers. ET-climate relationships in our Colorado basin receiving summer precipitation are more stable across subsurface drainage and storage characteristics. Climate driver-ET relationships are most sensitive to soil AWC and soil drainage parameters related to lateral redistribution in the relatively dry Sierra site that receives little summer precipitation. Our results demonstrate that uncertainty in geophysically mediated storage and drainage properties can strongly influence model estimates of watershed scale ET responses to climate variation and climate change. This sensitivity to uncertainty in geophysical properties is particularly true for sites receiving little summer precipitation. A parallel interpretation of this parameter sensitivity is that spatial variation in soil properties are likely to lead to substantial within-watershed plot scale differences in forest water use and drought stress.

  14. Modelling nitrogen and phosphorus loads in a Mediterranean river catchment (La Tordera, NE Spain

    Directory of Open Access Journals (Sweden)

    F. Caille

    2011-08-01

    Full Text Available Human activities have resulted in increased nutrient levels in many rivers all over Europe. Sustainable management of river basins demands an assessment of the causes and consequences of human alteration of nutrient flows, together with an evaluation of management options. In the context of an integrated and interdisciplinary environmental assessment (IEA of nutrient flows, we present and discuss the application of the nutrient emission model MONERIS (MOdelling Nutrient Emissions into River Systems to the Catalan river basin, La Tordera (North-East of Spain, for the period 1996-2002. After a successful calibration and verification process (Nash-Sutcliffe efficiencies E = 0.85 for phosphorus, and E = 0.86 for nitrogen, the application of the model MONERIS proved to be useful to estimate nutrient loads. Crucial for model calibration, in-stream retention (mainly affected by variability in precipitation was estimated to be about 50 % of nutrient emissions on an annual basis. Through this process, we identified the importance of point sources for phosphorus emissions (about 94 % for 1996–2002, and diffuse sources, especially inputs via groundwater, for nitrogen emissions (about 31 % for 1996–2002. Despite potential hurdles related to model structure, observed loads, and input data encountered during the modelling process, MONERIS provided a good representation of the major interannual and spatial patterns in nutrient emissions. An analysis of the model uncertainty and sensitivity to input data indicates that the model MONERIS, even in data-starved Mediterranean catchments, may be profitably used for evaluating quantitative nutrient emission scenarios that may help catchment managers and planners to develop effective policy and management measures to reduce nutrient loads.

  15. A framework of integrated hydrological and hydrodynamic models using synthetic rainfall for flash flood hazard mapping of ungauged catchments in tropical zones

    Science.gov (United States)

    Lohpaisankrit, Worapong; Meon, Günter; Tingsanchali, Tawatchai

    2016-05-01

    Flash flood hazard maps provide a scientific support to mitigate flash flood risk. The present study develops a practical framework with the help of integrated hydrological and hydrodynamic modelling in order to estimate the potential flash floods. We selected a small pilot catchment which has already suffered from flash floods in the past. This catchment is located in the Nan River basin, northern Thailand. Reliable meteorological and hydrometric data are missing in the catchment. Consequently, the entire upper basin of the main river was modelled with the help of the hydrological modelling system PANTA RHEI. In this basin, three monitoring stations are located along the main river. PANTA RHEI was calibrated and validated with the extreme flood events in June 2011 and July 2008, respectively. The results show a good agreement with the observed discharge data. In order to create potential flash flood scenarios, synthetic rainfall series were derived from temporal rainfall patterns based on the radar-rainfall observation and different rainfall depths from regional rainfall frequency analysis. The temporal rainfall patterns were characterized by catchment-averaged rainfall series selected from 13 rainstorms in 2008 and 2011 within the region. For regional rainfall frequency analysis, the well-known L-moments approach and related criteria were used to examine extremely climatic homogeneity of the region. According to the L-moments approach, Generalized Pareto distribution was recognized as the regional frequency distribution. The synthetic rainfall series were fed into the PANTA RHEI model. The simulated results from PANTA RHEI were provided to a 2-D hydrodynamic model (MEADFLOW), and various simulations were performed. Results from the integrated modelling framework are used in the ongoing study to regionalize and map the spatial distribution of flash flood hazards with four levels of flood severities. As an overall outcome, the presented framework can be applied in

  16. Improving the Distributed Hydrological Model Performance in Upper Huai River Basin: Using Streamflow Observations to Update the Basin States via the Ensemble Kalman Filter

    Directory of Open Access Journals (Sweden)

    Yongwei Liu

    2016-01-01

    Full Text Available This study investigates the capability of improving the distributed hydrological model performance by assimilating the streamflow observations. Incorrectly estimated model states will lead to discrepancies between the observed and estimated streamflow. Consequently, streamflow observations can be used to update the model states, and the improved model states will eventually benefit the streamflow predictions. This study tests this concept in upper Huai River basin. We assimilate the streamflow observations sequentially into the Soil and Water Assessment Tool (SWAT using the ensemble Kalman filter (EnKF to update the model states. Both synthetic experiments and real data application are used to demonstrate the benefit of this data assimilation scheme. The experiment shows that assimilating the streamflow observations at interior sites significantly improves the streamflow predictions for the whole basin. Assimilating the catchment outlet streamflow improves the streamflow predictions near the catchment outlet. In real data case, the estimated streamflow at the catchment outlet is significantly improved by assimilating the in situ streamflow measurements at interior gauges. Assimilating the in situ catchment outlet streamflow also improves the streamflow prediction of one interior location on the main reach. This may demonstrate that updating model states using streamflow observations can constrain the flux estimates in distributed hydrological modeling.

  17. Nitrate reduction in geologically heterogeneous catchments

    DEFF Research Database (Denmark)

    Refsgaard, Jens Christian; Auken, Esben; Bamberg, Charlotte A.; Christensen, Britt Stenhøj Baun; Clausen, Thomas; Dalgaard, Esben; Effersø, Flemming; Ernstsen, Vibeke; Gertz, Flemming; Hansen, Anne Lausten; He, Xin; Jacobsen, Brian H.; Jensen, Karsten Høgh; Jørgensen, Flemming; Jørgensen, Lisbeth Flindt; Koch, Julian; Nilsson, Bertel; Petersen, Christian; De Schepper, Guillaume; Schamper, Cyril; Sørensen, Kurt I.; Therrien, Rene; Thirup, Christian; Viezzoli, Andrea

    zone is reduced in the saturated zone before reaching the streams, and vulnerable areas, where no subsurface reduction takes place, and then only impose regulations/restrictions on the vulnerable areas. Distributed hydrological models can make predictions at grid scale, i.e. at much smaller scale than...... the entire catchment. However, as distributed models often do not include local scale hydrogeological heterogeneities, they are typically not able to make accurate predictions at scales smaller than they are calibrated. We present a framework for assessing nitrate reduction in the subsurface and for...... assessing at which spatial scales modelling tools have predictive capabilities. A new instrument has been developed for airborne geophysical measurements, Mini-SkyTEM, dedicated to identifying geological structures and heterogeneities with horizontal and lateral resolutions of 30–50 m and 2 m, respectively...

  18. Distributed catchment simulation using a raster GIS

    Science.gov (United States)

    Saghafian, Bahram; van Lieshout, Arno M.; Rajaei, Hossein M.

    Hydrologic simulation models can greatly benefit from geographic information system (GIS) capabilities for manipulation of input/output spatial data. This paper describes GIS-based pre-processing algorithms operating on elevation data that are applied in order to obtain flow direction and flow accumulation maps. Using the derived maps and other physical input data, kinematic travel-time maps, time-area histograms, and partial and total runoff hydrographs can be generated in a distributed modelling framework. The model was tested on a small watershed with satisfactory results. In its present state, the proposed model appears to work best for steep ungauged watersheds. Further validation for larger catchments requires more research. Some enhancements to the model are also recommended.

  19. Contribution of rainfall, snow and ice melt to the hydrological regime of the Arve upper catchment and to severe flood events

    Science.gov (United States)

    Lecourt, Grégoire; Revuelto, Jesús; Morin, Samuel; Zin, Isabella; Lafaysse, Matthieu; Condom, Thomas; Six, Delphine; Vionnet, Vincent; Charrois, Luc; Dumont, Marie; Gottardi, Frédéric; Laarman, Olivier; Coulaud, Catherine; Esteves, Michel; Lebel, Thierry; Vincent, Christian

    2016-04-01

    In Alpine catchments, the hydrological response to meteorological events is highly influenced by the precipitation phase (liquid or solid) and by snow and ice melt. It is thus necessary to simulate accurately the snowpack evolution and its spatial distribution to perform relevant hydrological simulations. This work is focused on the upper Arve Valley (Western Alps). This 205 km2 catchment has large glaciated areas (roughly 32% of the study area) and covers a large range of elevations (1000-4500 m a.s.l.). Snow presence is significant year-round. The area is also characterized by steep terrain and strong vegetation heterogeneity. Modelling hydrological processes in such a complex catchment is therefore challenging. The detailed ISBA land surface model (including the Crocus snowpack scheme) has been applied to the study area using a topography based discretization (classifying terrain by aspect, elevation, slope and presence of glacier). The meteorological forcing used to run the simulations is the reanalysis issued from the SAFRAN model which assimilates meteorological observations from the Meteo-France networks. Conceptual reservoirs with calibrated values of emptying parameters are used to represent the underground water storage. This approach has been tested to simulate the discharge on the Arve catchment and three sub-catchments over 1990-2015. The simulations were evaluated with respect to observed water discharges for several headwaters with varying glaciated areas. They allow to quantify the relative contribution of rainfall, snow and ice melt to the hydrological regime of the basin. Additionally, we present a detailed analysis of several particular flood events. For these events, the ability of the model to correctly represent the catchment behaviour is investigated, looking particularly to the relevance of the simulated snowpack. Particularly, its spatial distribution is evaluated using MODIS snow cover maps, punctual snowpack observations and summer

  20. Uncertainty in hydrological signatures for gauged and ungauged catchments

    Science.gov (United States)

    Westerberg, Ida K.; Wagener, Thorsten; Coxon, Gemma; McMillan, Hilary K.; Castellarin, Attilio; Montanari, Alberto; Freer, Jim

    2016-03-01

    Reliable information about hydrological behavior is needed for water-resource management and scientific investigations. Hydrological signatures quantify catchment behavior as index values, and can be predicted for ungauged catchments using a regionalization procedure. The prediction reliability is affected by data uncertainties for the gauged catchments used in prediction and by uncertainties in the regionalization procedure. We quantified signature uncertainty stemming from discharge data uncertainty for 43 UK catchments and propagated these uncertainties in signature regionalization, while accounting for regionalization uncertainty with a weighted-pooling-group approach. Discharge uncertainty was estimated using Monte Carlo sampling of multiple feasible rating curves. For each sampled rating curve, a discharge time series was calculated and used in deriving the gauged signature uncertainty distribution. We found that the gauged uncertainty varied with signature type, local measurement conditions and catchment behavior, with the highest uncertainties (median relative uncertainty ±30-40% across all catchments) for signatures measuring high- and low-flow magnitude and dynamics. Our regionalization method allowed assessing the role and relative magnitudes of the gauged and regionalized uncertainty sources in shaping the signature uncertainty distributions predicted for catchments treated as ungauged. We found that (1) if the gauged uncertainties were neglected there was a clear risk of overconditioning the regionalization inference, e.g., by attributing catchment differences resulting from gauged uncertainty to differences in catchment behavior, and (2) uncertainty in the regionalization results was lower for signatures measuring flow distribution (e.g., mean flow) than flow dynamics (e.g., autocorrelation), and for average flows (and then high flows) compared to low flows.

  1. Hydrological Dynamics In High Mountain Catchment Areas of Central Norway

    Science.gov (United States)

    Löffler, Jörg; Rößler, Ole

    different altitudinal belts. The local differences of temperature dynamics are illustrated in a map as an example of the low alpine altitudinal belt showing a 4-dimensional characterization (in space and time) of high mountain ecosystem functioning. Hydrological aspects derived from those results are presented showing the large- scaled hydrological dynamics of high mountain catchment basins in central Norway. The results of the process analysis of hydrological dynamics in the central Norwegian high mountains are discussed within the frame of investigations on altitudinal changes of mountain ecosystem structure and functioning (LÖFFLER &WUNDRAM [in print]). The poster illustrates the theoretical and methodological conception, methods and techniques, examples from complex data material as well as general outcomes of the project (RÖßLER [in prep.]. JUNG, G., J. LÖFFLER &D. WUNDRAM (1997): Untersuchungen zur Struktur, Funktion und Dynamik mittelnorwegischer Hochgebirgsökosysteme. Forschungsansatz. Oldenburger Geoökologisches Kolloquium 3: 4-36. Oldenburg. KÖHLER, B., J. LÖFFLER &D. WUNDRAM (1994): Probleme der kleinräumigen Geoökovarianz im mittelnorwegischen Gebirge. Norsk geogr. Tidsskr. 48: 99- 111. LÖFFLER, J. (1997): Großmaßstäbige geoökologische Kartierungen in den Höhenstufen des mittelnorwegischen Gebirges. NORDEN 12: 205-228. Bremen. LÖFFLER, J. (1998): Geoökologische Untersuchungen zur Struktur mittelnorwegischer Hochgebirgsökosysteme. Oldenburger Geoökologische Studien 1. Oldenburg. LÖFFLER, J., O.-D. FINCH, J. NAUJOK &R. PAPE (2001): Möglichkeiten der Integration zoologischer Aspekte in die landschaftsökologische Untersuchung von Hochgebirgen. Methodendiskussion am Beispiel ökologischer Prozesssysteme und Biozönosen. Naturschutz u. Landschaftsplanung 33 (11): 351-357. LÖFFLER, J. &D. WUNDRAM (1997): Klimatische Phänomene in mittelnorwegischen Hochgebirgslandschaften und ihre ökosystemare Bedeutung. Oldenburger Geoökologisches Kolloquium

  2. A catchment-integrated approach to determine the importance of secondary sources of contaminated sediment

    Science.gov (United States)

    Andres Lopez-Tarazon, Jose; Byrne, Patrick; Mullan, Donal; Smith, Hugh

    2015-04-01

    Water pollution has been identified as one of the most important environmental challenges of the early 21st Century. The Water Framework Directive (WFD) (2008/105/EC) explicitly recognises the risk to water resources posed by sediment-associated contaminants in European river basins. The potential impacts on water supply and the biodiversity of aquatic ecosystems from sediment and associated contaminants may be further exacerbated by climate change pressures on water resources, as highlighted in the 2009 EU White Paper "Adapting to climate change: Towards a European framework for action" (SEC(2009) 386, 387, 388). Despite these concerns, the role of floodplains and other storage areas as secondary sources of contaminated sediment (i.e. metals) in river basins affected by historic industrial or mining pollution has been largely overlooked. Thereby, besides the sediment which is transported by the river, secondary sources of contaminants represent a credible threat to achieving EU water quality targets set by the WFD. This project addresses this issue by developing a catchment-based approach looking at metal geochemistry from source to sink (i.e., from sediment generation at slopes, passing through sediment transported by the river system, to sediment deposition at the storage areas to the outlet) and develop a geochemical model to predict the chemical aspects of metals transport and transformation. This approach will allow us to quantify (i) the sediment fluxes and associated contaminants flowing through the river, (ii) the storage areas contributions to downstream contaminated sediment fluxes, (ii) the timescales for the storage and removal of contaminated sediment in the sinks, and (iv) the transformation and bioavailability of the pollutants (i.e. metals) along the basin. Both physical and chemical aspects of metal transport will be considered by looking at metal geochemistry, mobility and bioavailability, hence producing information on chemical metal transport

  3. Transferring model uncertainty estimates from gauged to ungauged catchments

    Directory of Open Access Journals (Sweden)

    F. Bourgin

    2014-07-01

    Full Text Available Predicting streamflow hydrographs in ungauged catchments is a challenging issue, and accompanying the estimates with realistic uncertainty bounds is an even more complex task. In this paper, we present a method to transfer model uncertainty estimates from gauged to ungauged catchments and we test it over a set of 907 catchments located in France. We evaluate the quality of the uncertainty estimates based on three expected qualities: reliability, sharpness, and overall skill. Our results show that the method holds interesting perspectives, providing in most cases reliable and sharp uncertainty bounds at ungauged locations.

  4. Soilwater dynamics related to waterlogging in a sloping catchment

    Science.gov (United States)

    Atputhanathan, C. S.; Gunawardena, E. R. N.; Rushton, K. R.

    1991-03-01

    A study to understand the factors contributing to waterlogging was conducted in a small catchment of 5.4 ha in an irrigation scheme in the Eastern Dry Zone of Sri Lanka. An analysis, based on climatological data, extensive measurements of inflows and outflows, groundwater head fluctuations, soil moisture content variations and soil properties, indicated that a single catchment water balance and the SEW index are of limited value due to the spatial nature of the waterlogging problem in this sloping catchment with surface irregularities. A distributed mathematical model was developed to represent the lateral and vertical components of flow; the agreement between the simulated and field results is satisfactory.

  5. Assessment of runoff contributing catchment areas in rainfall runoff modelling

    DEFF Research Database (Denmark)

    Thorndahl, Søren; Johansen, C.; Schaarup-Jensen, Kjeld

    2006-01-01

    In numerical modelling of rainfall caused runoff in urban sewer systems an essential parameter is the hydrological reduction factor which defines the percentage of the impervious area contributing to the surface flow towards the sewer. As the hydrological processes during a rainfall are difficult...... residential areas with mainly detached houses is recommended-contrary to the literature recommended values of 0.7-0.9....... now recommended literature values for residential areas. It is proven by comparing rainfall-runoff measurements from four different residential catchments that the literature values of the hydrological reduction factor are over-estimated for this type of catchment. In addition, different catchment...

  6. Modelling catchment areas for secondary care providers: a case study.

    Science.gov (United States)

    Jones, Simon; Wardlaw, Jessica; Crouch, Susan; Carolan, Michelle

    2011-09-01

    Hospitals need to understand patient flows in an increasingly competitive health economy. New initiatives like Patient Choice and the Darzi Review further increase this demand. Essential to understanding patient flows are demographic and geographic profiles of health care service providers, known as 'catchment areas' and 'catchment populations'. This information helps Primary Care Trusts (PCTs) to review how their populations are accessing services, measure inequalities and commission services; likewise it assists Secondary Care Providers (SCPs) to measure and assess potential gains in market share, redesign services, evaluate admission thresholds and plan financial budgets. Unlike PCTs, SCPs do not operate within fixed geographic boundaries. Traditionally, SCPs have used administrative boundaries or arbitrary drive times to model catchment areas. Neither approach satisfactorily represents current patient flows. Furthermore, these techniques are time-consuming and can be challenging for healthcare managers to exploit. This paper presents three different approaches to define catchment areas, each more detailed than the previous method. The first approach 'First Past the Post' defines catchment areas by allocating a dominant SCP to each Census Output Area (OA). The SCP with the highest proportion of activity within each OA is considered the dominant SCP. The second approach 'Proportional Flow' allocates activity proportionally to each OA. This approach allows for cross-boundary flows to be captured in a catchment area. The third and final approach uses a gravity model to define a catchment area, which incorporates drive or travel time into the analysis. Comparing approaches helps healthcare providers to understand whether using more traditional and simplistic approaches to define catchment areas and populations achieves the same or similar results as complex mathematical modelling. This paper has demonstrated, using a case study of Manchester, that when estimating

  7. Evaluation of fluxes of suspended matters and bedload in the small granitic Strengbach catchment (Vosges massif, France)

    Science.gov (United States)

    Cotel, Solenn; Viville, Daniel; Pierret, Marie Claire; Benarioumlil, Sylvain; Chabaux, François

    2016-04-01

    Transport of suspended matters (SM) and bedload in river controls the erosion process and elements export of a catchment. Furthermore, the SM are heavily involved in the migration of organic matter, metals and pollutants. The knowledge of the dynamics of the SM export is also essential to better understand the hydrogeochemical functioning of natural ecosystem. We investigated this question at the scale of a catchment; the Strengbach basin (site of OHGE - Observatoire Hydro-Géochimique de l'Environnement) where meteorological and hydrological data are monitored since 30 years. This small granitic basin (0,8km²) is located in the Vosges massif at altitudes between 883m and 1146m with 1400mm mean annual precipitations. A first evaluation of the solid fluxes exported at the Strengbach catchment was carried out on the basis of fortnightly sampling and measurement (Viville et al., 2012). Two automatic water samplers have been set up at the outlet of the basin in december 2012, in order to 1) evaluate the potential bias generated by the sampling frequency and 2) improve the SM flux calculation accuracy especially by taking into account the high flow events. These two samplers allowed regular sampling at 16h time step as well as high flow events sampling. At the same time, the bedload flux was estimated fortnightly by measuring the volume of sediments accumulated in a flume. However, the characteristics of the small Strengbach catchment (low water level, low SM concentration and mountainous winter climatic conditions) required to adapt the conventionally used systems. In this way, the SM annual flux estimated with the data from the two samplers varied between 7,5T and 8,8T during the three years of the study. By comparison, the SM annual flux obtained with previous method (only fortnightly sampling) was significantly different with values ranging from 2,8T to 16,6T. The contribution from each sampler and thus each sampling strategy to the improvement of the SM flux

  8. Stormwater retention basin efficiency regarding micropollutant loads and ecotoxicity.

    Science.gov (United States)

    Sébastian, Christel; Barraud, Sylvie; Gonzalez-Merchan, Carolina; Perrodin, Yves; Visiedo, Régis

    2014-01-01

    Retention basin efficiency in micropollutant removal has not been very well studied, in particular for pollutants highlighted by the European Water Framework Directive of 2000 such as pesticides, polybrominated diphenyl ethers (PBDEs) and alkylphenols. This study is based on in situ experiments carried out on a stormwater retention basin with the aim of estimating the basin efficiency in trapping and removing micropollutants from stormwater run-off from an industrial catchment drained by a separate sewer system. Along with stormwater, the basin receives some dry weather effluent flows, which are supposedly non-polluted. Ninety-four substances from five families (metals, polycyclic aromatic hydrocarbons (PAHs), PBDEs, alkylphenols and pesticides) were analyzed during 10 event campaigns in urban wet weather discharges at the inlet and outlet of the basin. The ecotoxicity of the samples was also tested. The results show high inter-event variability in both chemical and ecotoxic characteristics. They indicate good event efficiency concerning heavy metals and most PAHs. The studied pesticides, mainly found in the dissolved fraction, were not trapped. Particulate fraction study highlighted that settling is not the main process explaining micropollutant removal in a retention basin, as was noted for alkylphenols and PBDEs. PMID:24622545

  9. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: NLCD 2001 Land Use and Land Cover

    Science.gov (United States)

    Wieczorek, Michael E.; LaMotte, Andrew E.

    2010-01-01

    NHD catchments using an automated process (USEPA, 2007). The NHDPlus dataset is organized by 18 Production Units that cover the conterminous United States. The NHDPlus version 1.1 data are grouped by the U.S. Geologic Survey's Major River Basins (MRBs, Crawford and others, 2006). MRB1, covering the New England and Mid-Atlantic River basins, contains NHDPlus Production Units 1 and 2. MRB2, covering the South Atlantic-Gulf and Tennessee River basins, contains NHDPlus Production Units 3 and 6. MRB3, covering the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy River basins, contains NHDPlus Production Units 4, 5, 7 and 9. MRB4, covering the Missouri River basins, contains NHDPlus Production Units 10-lower and 10-upper. MRB5, covering the Lower Mississippi, Arkansas-White-Red, and Texas-Gulf River basins, contains NHDPlus Production Units 8, 11 and 12. MRB6, covering the Rio Grande, Colorado and Great Basin River basins, contains NHDPlus Production Units 13, 14, 15 and 16. MRB7, covering the Pacific Northwest River basins, contains NHDPlus Production Unit 17. MRB8, covering California River basins, contains NHDPlus Production Unit 18.

  10. Hydrogeological framework of the northern Draa-catchment, Morocco: Results of local and regional scale investigations

    International Nuclear Information System (INIS)

    base (autumn 2000, 2001) and high water flow conditions (spring 2001, 2002) the investigations allow a preliminary hydrogeological classification of the groundwater types in respect to their geogene mould, their seasonal variations and the origin of the water. More chemical and environmental isotope measurements are on the way to testify the classification. As an intermediary step in upscaling, hydrogeological investigations will focus on one important catchment area (sub regional scale). As a representative, the Asif n'Ait Ahmed catchment (60 km2) in the High Atlas is chosen. This catchment includes two test sites, already mapped. The geological mapping was accompanied by measurements of the groundwater quantity/quality, surface runoff and discharge of the receiving water course. Taking the size of the Upper Draa-catchment into account a different investigation strategy was chosen for the regional scale. The necessary geological and structural framework has been elucidated by both existing geological maps and geological evaluation of remote sensing data, added by selected ground checks. These information results in a first hydrogeological characterization. For a better understanding of the aquifer systems in respect to catchment area, age and groundwater recharge sampling campaigns have been carried out. Hydrogeological screening of the area between High Atlas - Basin of Ouarzazate - Anti-Atlas has been carried out in four profiles trending more or less N-S. The groundwater chemistry deviate considerably in both within and between the profiles. Observation points near the mountain rim hydrochemically exhibit a clear dependence on the nearby mountain geology. However, the hydrochemical pattern could not be used to solely determine the catchment area of the springs or wells. The environmental isotope measurements which have been performed show a reasonable correlation of δ2H/δ18O-data with the meteoric water. Deviations are partly due to enrichments by evaporation

  11. Temporal variations in the export of REE in boreal catchments of varying character and size

    Science.gov (United States)

    Köhler, S.; Lidman, F.; Mörth, M.; Björkvald, L.; Laudon, H.

    2009-04-01

    . Geochimica Et Cosmochimica Acta 71(11), 2718-2735. Steinmann M. and Stille P. (2008) Controls on transport and fractionation of the rare earth elements in stream water of a mixed basaltic-granitic catchment basin (Massif Central, France). Chemical Geology 254(1-2), 1-18. Tipping E. (1998) Humic Ion-Binding Model VI: An improved Description of the Intercations of Protons and Metal Ions with Humic Substances. Aquatic Geochemistry 4, 3-48.

  12. Considerations on the influence of extreme events on the phosphorus transport from river catchments to the sea.

    Science.gov (United States)

    Zessner, M; Postolache, C; Clement, A; Kovacs, A; Strauss, P

    2005-01-01

    In this paper, results from rivers of different sizes in Romania, Hungary and Austria are presented. The paper shows the dynamics of extreme events and their contribution to the total P and suspended solids transported in these rivers. Special attention is paid to the influence of the size of the catchment and the event probability on the relative contribution of a single event to the total loads transported in the river. Further, the development of phosphorus loads along the Danube River at a flood event is shown. From the results it can be concluded that there is no immediate influence of high flow and flood events in upstream parts of the Basin on the transport of phosphorus from the catchment to the receiving Sea. Particle-bound phosphorus is mobilised from the catchment (through erosion) and the river bottom to a high extent at high flow events and transported at peak discharges to downstream, where retention by sedimentation of particles takes place. On the one hand this retention is a transport to flooded areas. In this case it can be considered as more or less long term retention. On the other hand sedimentation takes place in the riverbed, in case the tractive effort of the river is reduced. In this second case the P-pool in the sediments of the sedimentation area will be increased. If anaerobic conditions in the sediment appear, part of the phosphorus will be transformed to soluble ortho-phosphate and will continuously contribute to the phosphorus transport to the receiving sea. Part of the P-retained in the river sediment will be mobilised by resuspension at the next biggest high flow event. Altogether, these alternating processes of suspension, transport, export to flooded areas or sedimentation in the river bed with partly solution and partly resuspension at the next event decrease the share of the phosphorus transport during high flow events on the total loads transported in the more downstream parts of a catchments as compared to the more upstream

  13. Identifying residence times and streamflow generation processes using δ18O and δ2H in meso-scale catchments in the Abay/Upper Blue Nile, Ethiopia

    Directory of Open Access Journals (Sweden)

    S. Tekleab

    2013-08-01

    Full Text Available Measurements of the stable isotopes oxygen-18 (18O and deuterium (2H were carried out in two meso-scale catchments, Chemoga (358 km2 and Jedeb (296 km2 south of Lake Tana, Abay/Upper Blue Nile basin, Ethiopia. The region is of paramount importance for the water resources in the Nile basin. Stable isotope composition in precipitation, spring water and streamflow were analyzed (i to characterize the spatial and temporal variations of water fluxes; (ii to estimate the mean residence time of water using a sine wave regression approach; and (iii to identify runoff components using classical two component hydrograph separations at a seasonal time scale. The results show that the isotopic composition of precipitation exhibit marked seasonal variations, which suggests different sources of moisture generation for the rainfall in the study area. The Atlantic–Indian ocean, Congo basin, and the Sud swamps are the likely the potential moisture source areas during the main rainy (summer season. While, the Indian–Arabian, and Mediterranean Sea moisture source areas during little rain (spring, and dry (winter seasons. The spatial variation of the isotopic composition is affected by the amount effect and to less extent by altitude and temperature effects. A mean altitude effect of −0.12‰ (100 m−1 for 18O and −0.58‰ (100 m−1 for 2H were discernable in precipitation isotope composition. The seasonal variations of the isotopic signature of the spring water exhibit a damped response as compared to the river waters, which shows that the spring water has longer residence times than the river water. Results from the hydrograph separation at a seasonal time scale indicate the dominance of event water with an average of 71% and 64% of the total runoff during the wet season in the Chemoga and Jedeb catchment, respectively. The stable isotope compositions of streamflow samples were damped compared to the input function of precipitation for both catchments

  14. Introduction to paleoenvironments of Bear Lake, Utah and Idaho, and its catchment

    Science.gov (United States)

    Rosenbaum, Joseph G.; Kaufman, Darrell S.

    2009-01-01

    In 1996 a group led by the late Kerry Kelts (University of Minnesota) and Robert Thompson (U.S. Geological Survey) acquired three piston cores (BL96-1, -2, and -3) from Bear Lake. The coring arose from their recognition of Bear Lake as a potential repository of long records of paleoenvironmental change. They recognized that the lake is located in an area that is sensitive to changes in regional climate patterns (Dean et al., this volume), that the lake basin is long lived (see Colman, 2006; Kaufman et al., this volume), and that, unlike many lakes in the Great Basin, Bear Lake was never dry during warm dry periods. Bear Lake lies in the northeastern Great Basin to the northeast of Great Salt Lake, just south of the Snake River drainage, and a short distance west of the Green River drainage that makes up part of the Upper Colorado River Basin (Fig. 1). Similarity among the historic Bear Lake and Great Salt Lake hydrographs and flows on the Green River indicates that the hydrology of Bear Lake reflects regional precipitation (Fig. 2). Therefore, paleorecords from Bear Lake are important to understanding past climate for a large region, including the Upper Colorado River Basin, the source of much of the water for the southwestern United States. Initially, paleoenvironmental studies of Bear Lake sediments focused on cores BL96-1, -2, and -3. Additional coring was conducted to elucidate the spatial distribution of sedimentary units and to extend the record back in time. The study was also expanded to include extensive study of the catchment, including the properties of catchment materials and the processes that could potentially affect the delivery of catchment materials to the lake. Cores BL96-1, -2, and -3 were taken with a Kullenburg piston corer along an east–west profile in roughly 50, 40, and 30 m of water, respectively (Table 1, Fig. 3). These three cores, each taken as a single 4- to 5-m-long segment, provide a nearly complete composite section from ca. 26 cal

  15. Integrated Nitrogen CAtchment model (INCA) applied to a tropical catchment in the Atlantic Forest, São Paulo, Brazil

    OpenAIRE

    Ranzini, M.; Forti, M. C.; Whitehead, P. G.; Arcova, F. C. S.; De Cicco, V.; Wade, A. J.

    2007-01-01

    Stream-water flows and in-stream nitrate and ammonium concentrations in a small (36.7 ha) Atlantic Forest catchment were simulated using the Integrated Nitrogen in CAtchments (INCA) model version 1.9.4. The catchment, at Cunha, is in the Serra do Mar State Park, SE Brazil and is nearly pristine because the nearest major conurbations, São Paulo and Rio, are some 450 km distant. However, intensive farming may increase nitrogen (N) deposition and there are growing pressures for urbanisation. The...

  16. Nutrient concentrations and fluxes in the upper catchment of the Miyun Reservoir, China, and potential nutrient reduction strategies.

    Science.gov (United States)

    Jiao, Jian; Du, Pengfei; Lang, Cong

    2015-03-01

    The Miyun Reservoir is Beijing's main drinking water source. Increased nutrient levels in the reservoir have resulted in an increased risk of harmful algal blooms. One hundred ten water samples were collected at a range of spatial scales in the upper catchment of the Miyun Reservoir and were analyzed for total nitrogen (TN), nitrate (NO3 (-)-N), ammonium (NH4 (+)-N), total phosphorus (TP), and the potassium permanganate index (CODMn). Empirical equations were developed from relationships between nutrient concentrations and the main controls on nutrient, and were used to identify parts of the catchment that should be targeted with nutrient load reduction measures. Cropland was the main source of sediment for the streams, and much of the phosphorus was associated with sediment. The annual mean TP concentrations were closely correlated with both the annual mean suspended sediment concentrations and the ratio of the cropland area to the total basin area. There was a linear relationship between the annual mean TN concentration and the population density in the basins. Soil conservation may play an important role in reducing TP concentrations in the upper reaches of the Chao and Bai Rivers. It may be useful to (1) construct natural riparian buffers and vegetated buffers along croplands close to the watercourses, (2) implement management strategies to reduce nitrogen (N) fertilizer applications, and (3) construct additional wetlands to reduce nutrient loads in the study area. PMID:25673273

  17. Understanding the relative role of dispersion mechanisms across basin scales

    Science.gov (United States)

    Di Lazzaro, M.; Zarlenga, A.; Volpi, E.

    2016-05-01

    Different mechanisms are understood to represent the primary sources of the variance of travel time distribution in natural catchments. To quantify the fraction of variance introduced by each component, dispersion coefficients have been earlier defined in the framework of geomorphology-based rainfall-runoff models. In this paper we compare over a wide range of basin sizes and for a variety of runoff conditions the relative role of geomorphological dispersion, related to the heterogeneity of path lengths, and hillslope kinematic dispersion, generated by flow processes within the hillslopes. Unlike previous works, our approach does not focus on a specific study case; instead, we try to generalize results already obtained in previous literature stemming from the definition of a few significant parameters related to the metrics of the catchment and flow dynamics. We further extend this conceptual framework considering the effects of two additional variance-producing processes: the first covers the random variability of hillslope velocities (i.e. of travel times over hillslopes); the second deals with non-uniform production of runoff over the basin (specifically related to drainage density). Results are useful to clarify the role of hillslope kinematic dispersion and define under which conditions it counteracts or reinforces geomorphological dispersion. We show how its sign is ruled by the specific spatial distribution of hillslope lengths within the basin, as well as by flow conditions. Interestingly, while negative in a wide range of cases, kinematic dispersion is expected to become invariantly positive when the variability of hillslope velocity is large.

  18. Pesticide and metabolite fate, release and transport modelling at catchment scale

    Science.gov (United States)

    Gaßmann, Matthias; Olsson, Oliver; Bauer, Melanie

    2010-05-01

    Pesticides are of great concern in hydrological catchments all over the world. On the one hand they are necessary to guarantee stable agricultural production for an increasing population. On the other hand they endanger life of aquatic animals and freshwater resources. However, not only pesticides but also their degradation products, the metabolites, are toxic to the environment, in some cases even more than the parent material. Thus, it is necessary to optimize pesticide application and management of agricultural land (e.g. grass strips, erosion prevention) with respect and according to their behaviour and degradation in hydrological catchments. Modelling provides a sound tool for assessing the impacts of pesticide management changes on pesticide behaviour at the field and in consecutively surface waters. Most of the various models available in literature do not consider metabolism. This study introduces an applicable integrated model assessing the fate and release of a pesticide and one metabolite at the field and in surface waters of a hydrological catchment. For the development of the field release model, the single-equation pesticide release formula by the OECD (2000) was used, which combines sorption and degradation in one equation. The part of the equation calculating the degradation forms the input of a second OECD equation representing the metabolite with its own parameters. A fraction can be specified describing how much of the degradation product is transferred to the specific metabolite. The river network is simulated with a further development of the MOHID River Network model (MRN). The integration of a pesticide type and a metabolite, with their degradation and volatilization processes are the main improvements of the hydrodynamic channel model. Following, the combined model was set up to the Israeli part of the Upper Jordan River basin, especially the Hula valley. According to the local hydrological conditions, a linear storage with a threshold was

  19. Predicting in ungauged basins using a parsimonious rainfall-runoff model

    Science.gov (United States)

    Skaugen, Thomas; Olav Peerebom, Ivar; Nilsson, Anna

    2015-04-01

    Prediction in ungauged basins is a demanding, but necessary test for hydrological model structures. Ideally, the relationship between model parameters and catchment characteristics (CC) should be hydrologically justifiable. Many studies, however, report on failure to obtain significant correlations between model parameters and CCs. Under the hypothesis that the lack of correlations stems from non-identifiability of model parameters caused by overparameterization, the relatively new parameter parsimonious DDD (Distance Distribution Dynamics) model was tested for predictions in ungauged basins in Norway. In DDD, the capacity of the subsurface water reservoir M is the only parameter to be calibrated whereas the runoff dynamics is completely parameterised from observed characteristics derived from GIS and runoff recession analysis. Water is conveyed through the soils to the river network by waves with celerities determined by the level of saturation in the catchment. The distributions of distances between points in the catchment to the nearest river reach and of the river network give, together with the celerities, distributions of travel times, and, consequently unit hydrographs. DDD has 6 parameters less to calibrate in the runoff module than, for example, the well-known Swedish HBV model. In this study, multiple regression equations relating CCs and model parameters were trained from 84 calibrated catchments located all over Norway and all model parameters showed significant correlations with catchment characteristics. The significant correlation coefficients (with p- value < 0.05) ranged from 0.22-0.55. The suitability of DDD for predictions in ungauged basins was tested for 17 catchments not used to estimate the multiple regression equations. For 10 of the 17 catchments, deviations in Nash-Suthcliffe Efficiency (NSE) criteria between the calibrated and regionalised model were less than 0.1. The median NSE for the regionalised DDD for the 17 catchments, for two

  20. Transferring global uncertainty estimates from gauged to ungauged catchments

    Directory of Open Access Journals (Sweden)

    F. Bourgin

    2015-05-01

    Full Text Available Predicting streamflow hydrographs in ungauged catchments is challenging, and accompanying the estimates with realistic uncertainty bounds is an even more complex task. In this paper, we present a method to transfer global uncertainty estimates from gauged to ungauged catchments and we test it over a set of 907 catchments located in France, using two rainfall–runoff models. We evaluate the quality of the uncertainty estimates based on three expected qualities: reliability, sharpness, and overall skill. The robustness of the method to the availability of information on gauged catchments was also evaluated using a hydrometrical desert approach. Our results show that the method presents advantageous perspectives, providing reliable and sharp uncertainty bounds at ungauged locations in a majority of cases.

  1. A catchment scale water balance model for FIFE

    Science.gov (United States)

    Famiglietti, J. S.; Wood, E. F.; Sivapalan, M.; Thongs, D. J.

    1992-01-01

    A catchment scale water balance model is presented and used to predict evaporation from the King's Creek catchment at the First ISLSCP Field Experiment site on the Konza Prairie, Kansas. The model incorporates spatial variability in topography, soils, and precipitation to compute the land surface hydrologic fluxes. A network of 20 rain gages was employed to measure rainfall across the catchment in the summer of 1987. These data were spatially interpolated and used to drive the model during storm periods. During interstorm periods the model was driven by the estimated potential evaporation, which was calculated using net radiation data collected at site 2. Model-computed evaporation is compared to that observed, both at site 2 (grid location 1916-BRS) and the catchment scale, for the simulation period from June 1 to October 9, 1987.

  2. Extreme inflow events and synoptic forcing in Sydney catchments

    Energy Technology Data Exchange (ETDEWEB)

    Pepler, Acacia S; Rakich, Clinton S, E-mail: a.pepler@bom.gov.a [NSW Climate Services Section, Bureau of Meteorology PO Box 413, Darlinghurst, NSW 1300 (Australia)

    2010-08-15

    The Sydney catchment region encompasses over 16,000km{sup 2}, supplying water to over 4 million inhabitants. However, few studies have investigated the synoptic and climatic influences on inflow in this region, which are crucial for understanding the vulnerability of water supply in a changing climate. This study identifies extremely high and low inflow events between 1960 and 2008 based on catchment averages. The focus of the study is an analysis of the synoptic cause/s of each extreme inflow event. The events are evaluated to identify any trends and also to determine the concurrent significant climatic influences on rainfall over the catchments. Relationships between catchment inflow, rainfall, tropical SST indices, and other influencing factors such as observed wind and temperatures are investigated. Our results show that East Coast Lows and anomalously easterly flow are the drivers of high inflow events, with low inflow events dominated by westerly wind patterns and the El Nino-Southern Oscillation.

  3. Effects of input discretization, model complexity, and calibration strategy on model performance in a data-scarce glacierized catchment in Central Asia

    Science.gov (United States)

    Tarasova, L.; Knoche, M.; Dietrich, J.; Merz, R.

    2016-06-01

    Glacierized high-mountainous catchments are often the water towers for downstream region, and modeling these remote areas are often the only available tool for the assessment of water resources availability. Nevertheless, data scarcity affects different aspects of hydrological modeling in such mountainous glacierized basins. On the example of poorly gauged glacierized catchment in Central Asia, we examined the effects of input discretization, model complexity, and calibration strategy on model performance. The study was conducted with the GSM-Socont model driven with climatic input from the corrected High Asia Reanalysis data set of two different discretizations. We analyze the effects of the use of long-term glacier volume loss, snow cover images, and interior runoff as an additional calibration data. In glacierized catchments with winter accumulation type, where the transformation of precipitation into runoff is mainly controlled by snow and glacier melt processes, the spatial discretization of precipitation tends to have less impact on simulated runoff than a correct prediction of the integral precipitation volume. Increasing model complexity by using spatially distributed input or semidistributed parameters values does not increase model performance in the Gunt catchment, as the more complex model tends to be more sensitive to errors in the input data set. In our case, better model performance and quantification of the flow components can be achieved by additional calibration data, rather than by using a more distributed model parameters. However, a semidistributed model better predicts the spatial patterns of snow accumulation and provides more plausible runoff predictions at the interior sites.

  4. Quantifying human impacts on catchment sediment yield: A continental approach

    Science.gov (United States)

    Vanmaercke, Matthias; Poesen, Jean; Govers, Gerard; Verstraeten, Gert

    2015-07-01

    Both from a scientific and environmental management perspective, there is a large need to assess the magnitude and controlling factors of human impacts on catchment sediment yield. Quantifying this impact is difficult, since it requires knowing both the actual sediment yield (SYa, [t km- 2 y- 1]) as well as the corresponding "pristine" value of a catchment (SYp, [t km- 2 y- 1]; i.e. the sediment yield that can be expected if the catchment was not affected by humans). Here we address this problem by comparing measured SYa values for 165 European catchments that were unaffected by dams or reservoirs with their corresponding SYp, which were predicted using a recently developed regression model. The ratio between these two values is expected to reflect the degree of human impact on catchment sediment yield (HIF). Correlation and partial correlation analyses showed that spatial variability in HIF is mainly explained by differences in land use (i.e. the fraction of arable land) and catchment area. The effect of these two factors was clearly linked in western and central Europe: whereas SYa can be easily 40 times higher than SYp in intensively cultivated small (≤ 1 km2) catchments, the difference is negligible for large (> 1000 km2) catchments with the same land use. While, this concurs with our knowledge that the effects of land use (change) on erosion rates can be buffered at the catchment scale, this study provides a first robust quantification of this effect. Apart from a potential climatic effect (i.e. a correlation between HIF and the average annual air temperature) no other factors could be identified that are significant in explaining observed differences in HIF. This indicates that HIF is mainly controlled by catchment scale and land use, while other factors may be only of secondary importance at an intra-continental scale. Nonetheless, more accurate quantifications of these HIF values and more refined characterizations of the catchments in terms of (historical

  5. Groundwater and surface water interaction for integrated catchment planning

    OpenAIRE

    Aradas, Rodolfo D.

    2005-01-01

    Integrated Catchment Management (ICM), defined as the design of intervention strategies encompassing and integrating the fields of hydrology, environmental, social and economic science, is vital in order to reach sustainable solutions on a catchment basis. Modelling lies at the core of the ICM process as it supports baseline studies and enables analysis of proposed intervention measures both for present day conditions and under future scenarios. Its core role in ICM leads to the need to devel...

  6. Rainfall, runoff and sediment transport in a Mediterranean mountainous catchment.

    Science.gov (United States)

    Tuset, J; Vericat, D; Batalla, R J

    2016-01-01

    The relation between rainfall, runoff, erosion and sediment transport is highly variable in Mediterranean catchments. Their relation can be modified by land use changes and climate oscillations that, ultimately, will control water and sediment yields. This paper analyses rainfall, runoff and sediment transport relations in a meso-scale Mediterranean mountain catchment, the Ribera Salada (NE Iberian Peninsula). A total of 73 floods recorded between November 2005 and November 2008 at the Inglabaga Sediment Transport Station (114.5 km(2)) have been analysed. Suspended sediment transport and flow discharge were measured continuously. Rainfall data was obtained by means of direct rain gauges and daily rainfall reconstructions from radar information. Results indicate that the annual sediment yield (2.3 t km(-1) y(-1) on average) and the flood-based runoff coefficients (4.1% on average) are low. The Ribera Salada presents a low geomorphological and hydrological activity compared with other Mediterranean mountain catchments. Pearson correlations between rainfall, runoff and sediment transport variables were obtained. The hydrological response of the catchment is controlled by the base flows. The magnitude of suspended sediment concentrations is largely correlated with flood magnitude, while sediment load is correlated with the amount of direct runoff. Multivariate analysis shows that total suspended load can be predicted by integrating rainfall and runoff variables. The total direct runoff is the variable with more weight in the equation. Finally, three main hydro-sedimentary phases within the hydrological year are defined in this catchment: (a) Winter, where the catchment produces only water and very little sediment; (b) Spring, where the majority of water and sediment is produced; and (c) Summer-Autumn, when little runoff is produced but significant amount of sediments is exported out of the catchment. Results show as land use and climate change may have an important

  7. Hydrological response of a small catchment burned by experimental fire

    OpenAIRE

    Stoof, C.R.; R. W. Vervoort; Iwema, J.; Elsen, E.; Ferreira, A. J. D.; Ritsema, C.J.

    2011-01-01

    Fire can considerably change hydrological processes, increasing the risk of extreme flooding and erosion events. Although hydrological processes are largely affected by scale, catchment-scale studies on the hydrological impact of fire are scarce, and nested approaches are rarely used. Taking a unique approach, we performed a catchment-scale experimental fire to improve insight into the drivers of fire impact on hydrology. In north-central Portugal, rainfall, canopy interception, streamflow an...

  8. Susceptibility of Shallow Landslide in Fraser Hill Catchment, Pahang Malaysia

    OpenAIRE

    Wan Nor Azmin Sulaiman

    2010-01-01

    In tropical areas especially during monsoon seasons intense precipitation is the main caused that trigger the natural shallow landslide phenomena. This phenomenon can be disastrous and widespread in occurrence even in undisturbed forested catchment. In this paper, an attempt has been made to evaluate the susceptibility of natural hill slopes to failure for a popular hill resort area, the Fraser Hill Catchment under different rainfall regimes and soil thickness. A Digital Elevation Model (DEM)...

  9. ASSESSMENT OF THE FLOODS POTENTIAL IN JIU RIVER CATCHMENT

    OpenAIRE

    TELTEU CAMELIA ELIZA; BRĂNESCU EMILIA; BERGHEZAN AURELIA

    2014-01-01

    The floods are extreme hydrological events that require rigorous analysis to achieve structural and non – structural measures to mitigate their risk. This paper aims to analyze the floods’ potential in the Jiu River Catchment (the catchment area has 10131 km²). The main geographical factors which are favoring the floods production are the climatic conditions and the morphometric factors. The monthly and annual maximum discharge recorded at 18 hydrometric stations, have been analyzed for the i...

  10. A Flash Flood Study on the Small Montaneous River Catchments in Western Romania

    Science.gov (United States)

    Győri, Maria-Mihaela; Haidu, Ionel; Humbert, Joël

    2013-04-01

    interpolated in order to obtain the hydrograph of the historical flash floods. The two methodologies employed offer the hydrologist the opportunity of computing the historical hydrographs be it on a section of the river at choice, or for every affluent within the small river basins studied, the graphical data being easily accessed both in GIS and HEC-HMS. The peak discharge values of the main rivers as well as those of their tributaries are of great importance in establishing the hydrologic hazard under the form of floodplain maps that are inexistent for the studied watersheds. Key words: flash flood modeling, ungauged catchments, GIS, HEC-HMS rainfall-runoff model. Aknowledgements This work was possible with the financial support of the Sectoral Operational Programme for Human Resources Development 2007-2013, co-financed by the European Social Fund, under the project number POSDRU/107/1.5/S/76841 with the title "Modern Doctoral Studies: Internationalization and Interdisciplinarity".

  11. Predicting aquifer response time for application in catchment modeling.

    Science.gov (United States)

    Walker, Glen R; Gilfedder, Mat; Dawes, Warrick R; Rassam, David W

    2015-01-01

    It is well established that changes in catchment land use can lead to significant impacts on water resources. Where land-use changes increase evapotranspiration there is a resultant decrease in groundwater recharge, which in turn decreases groundwater discharge to streams. The response time of changes in groundwater discharge to a change in recharge is a key aspect of predicting impacts of land-use change on catchment water yield. Predicting these impacts across the large catchments relevant to water resource planning can require the estimation of groundwater response times from hundreds of aquifers. At this scale, detailed site-specific measured data are often absent, and available spatial data are limited. While numerical models can be applied, there is little advantage if there are no detailed data to parameterize them. Simple analytical methods are useful in this situation, as they allow the variability in groundwater response to be incorporated into catchment hydrological models, with minimal modeling overhead. This paper describes an analytical model which has been developed to capture some of the features of real, sloping aquifer systems. The derived groundwater response timescale can be used to parameterize a groundwater discharge function, allowing groundwater response to be predicted in relation to different broad catchment characteristics at a level of complexity which matches the available data. The results from the analytical model are compared to published field data and numerical model results, and provide an approach with broad application to inform water resource planning in other large, data-scarce catchments. PMID:24842053

  12. Interaction of water components in the semi-arid Huasco and Limarí river basins, North Central Chile

    Directory of Open Access Journals (Sweden)

    G. Strauch

    2009-10-01

    Full Text Available For sustainable water resource management in semi-arid regions, sound information is required about interactions between the different components of the water system: rain/snow precipitation, surface/subsurface run-off, groundwater recharge. Exemplarily, the Huasco and Limarí river basins as water stressed river catchments have been studied by isotope and hydrochemical methods for (i the origin of water, (ii water quality, (iii relations of surface and groundwater.

    Applying the complex multi-isotopic and hydrochemical methodology to the water components of the Huasco and Limarí basins, a differentiation of water components concerning subsurface flow and river water along the catchment area and by anthropogenic impacts are detected. Sulphate and nitrate concentrations indicate remarkable input from mining and agricultural activities along the river catchment.

    The 2H-18O relations of river water and groundwater of both catchments point to the behaviour of river waters originated in an arid to semi-arid environment.

    Consequently, the groundwater from several production wells in the lower parts of the catchments is related to the rivers where the wells located, however, it can be distinguished from the river water. Using the hydrological water balance and the isotope mixing model, the interaction between surface and subsurface flows and river flow is estimated.

  13. Temporal and Spatial Patterns of Preferential Flow Occurrence in the Shale Hills Catchment: From the Hillslope to the Catchment Scales

    Science.gov (United States)

    Liu, H.; Lin, H.

    2013-12-01

    Understanding temporal and spatial patterns of preferential flow (PF) occurrence is important in revealing hillslope and catchment hydrologic and biogeochemical processes. Quantitative assessment of the frequency and control of PF occurrence in the field, however, has been limited, especially at the landscape scale of hillslope and catchment. By using 5.5-years' (2007-2012) real-time soil moisture at 10 sites response to 323 precipitation events, we tested the temporal consistency of PF occurrence at the hillslope scale in the forested Shale Hills Catchment; and by using 25 additional sites with at least 1-year data (2011-2012), we evaluated the spatial patterns of PF occurrence across the catchment. To explore the potential effects of PF occurrence on catchment hydrology, wavelet analysis was performed on the recorded time series of hydrological signals (i.e., precipitation, soil moisture, catchment discharge). Considerable temporal consistence was observed in both the frequency and the main controls of PF occurrence at the hillslope scale, which was attributed largely to the statistical stability of precipitation pattern over the monitoring period and the relatively stable subsurface preferential pathways. Preferential flow tended to occur more often in response to intense rainfall events, and favored the conditions at dry hilltop or wet valley floor sites. When upscaling to the entire catchment, topographic control on the PF occurrence was amplified remarkably, leading to the identification of a subsurface PF network in the catchment. Higher frequency of PF occurrence was observed at the valley floor (average 48%), hilltop (average 46%), and swales/hillslopes near the stream (average 40%), while the hillslopes in the eastern part of the catchment were least likely to experience PF (0-20%). No clear relationship, however, was observed between terrain attributes and PF occurrence, because the initiation and persistency of PF in this catchment was controlled

  14. Impacts of climate change on the water balance of a large nonhumid natural basin in China

    Science.gov (United States)

    Liu, Qiang; Liang, Liqiao

    2015-08-01

    Water resources are contingent on the combined effects of climate change and watershed characteristics. An analytical model devised from the Budyko framework was used to investigate the partitioning of precipitation ( P) into actual evapotranspiration ( E) and streamflow ( Q) parameters for the Yellow River Basin (YRB), a water-limited basin, to estimate the response of E and Q to P and potential evapotranspiration ( E p ). Although a steady state was assumed, the analytical model, incorporating an adjustable parameter characteristic of catchment conditions ( ω), can be run to analyze the sensitivity of catchment characteristics on water resources. The theory predicts that Q and E are more sensitive to P than to E p . For example, a 10 % increase in P will result in a 22.8 % increase in Q, while a 10 % increase in E p will decrease Q by 13.2 %. The model shows that, to some extent, water balance is governed by changing catchment characteristics (such as changes in vegetation on annual scales). These findings indicate that additional elucidative data can be drawn from the Budyko framework when taking into account catchment characteristics. Furthermore, the model can analyze the response of water resources to climate change on different temporal and spatial scales.

  15. An elusive search for regional flood frequency estimates in the River Nile basin

    Directory of Open Access Journals (Sweden)

    P. Nyeko-Ogiramoi

    2012-09-01

    Full Text Available Estimation of peak flow quantiles in ungauged catchments is a challenge often faced by water professionals in many parts of the world. Approaches to address such problem exist, but widely used techniques such as flood frequency regionalisation is often not subjected to performance evaluation. In this study, the jack-knifing principle is used to assess the performance of the flood frequency regionalisation in the complex and data-scarce River Nile basin by examining the error (regionalisation error between locally and regionally estimated peak flow quantiles for different return periods (QT. Agglomerative hierarchical clustering based algorithms were used to search for regions with similar hydrological characteristics. Hydrological data employed were from 180 gauged catchments and several physical characteristics in order to regionalise 365 identified catchments. The Generalised Extreme Value (GEV distribution, selected using L-moment based approach, was used to construct regional growth curves from which peak flow growth factors could be derived and mapped through interpolation. Inside each region, variations in at-site flood frequency distribution were modelled by regression of the mean annual maximum peak flow (MAF versus catchment area. The results showed that the performance of the regionalisation is heavily dependent on the historical flow record length and the similarity of the hydrological characteristics inside the regions. The flood frequency regionalisation of the River Nile basin can be improved if sufficient flow data of longer record length of at least 40 yr become available.

  16. Characterization of catchment behaviour and rainfall selection for flash flood hydrological model calibration: catchments of the eastern Pyrenees

    OpenAIRE

    Garambois, Pierre-André; Roux, Hélène; Larnier, Kévin; Labat, David; Dartus, Denis

    2015-01-01

    International audience Accurate flash flood prediction depends heavily on rainfall data quality and knowledge of catchment behaviour. A methodology based on global sensitivity analysis and hydrological similarity is proposed to analyse flash storm-flood events with a mechanistic model. The behaviour of medium-sized catchments is identified in terms of rainfall-runoff conservation. On the basis of this shared behaviour, rainfall products with questionable quantitative precipitation estimati...

  17. Morphometrical Analysis and Peak Runoff Estimation for the Sub-Lower Niger River Basin, Nigeria

    Science.gov (United States)

    Salami, Adebayo Wahab; Amoo, Oseni Taiwo; Adeyemo, Joshiah Adetayo; Mohammed, Abdulrasaq Apalando; Adeogun, Adeniyi Ganiyu

    2016-03-01

    This study utilized Spatial Information Technology (SIT) such as Remote Sensing (RS), a Geographical Information System (GIS), the Global Positioning System (GPS) and a high-resolution Digital Elevation Model (DEM) for a morphometrical analysis of five sub-basins within the Lower Niger River Basin, Nigeria. Morpho-metrical parameters, such as the total relief, relative relief, relief ratio, ruggedness number, texture ratio, elongation ratio, circularity ratio, form factor ratio, drainage density, stream frequency, sinuosity factor and bifurcation ratio, have been computed and analyzed. The study revealed that the contribution of the morphometric parameters to flooding suggest catchment No. 1 has the least concentration time and the highest runoff depth. Catchment No. 4 has the highest circularity ratio (0.35) as the most hazardous site where floods could reach a great volume over a small area.

  18. Catchment clearing accelerates the infilling of a shallow subtropical bay in east coast Australia

    Science.gov (United States)

    Coates-Marnane, Jack; Olley, Jon; Burton, Joanne; Sharma, Ashneel

    2016-06-01

    Understanding processes that govern the transport and distribution of terrestrial sediments to and within bays is critical for interpreting the drivers of long-term changes in these ecosystems. On the east coast of Australia increased soil erosion and sediment delivery following extensive land clearing in the contributing catchments, associated with European settlement, is highlighted as a key driver of the decline of numerous nearshore habitats including seagrass meadows and in-shore coral reefs. Here we use optical, radiocarbon and radionuclide dating to estimate mass accumulation rates and type of terrestrial sedimentation in central Moreton Bay during the Holocene. We compare the long-term rates of infilling within the central basin with the recent past and show a 3-9 fold increase in sediment accretion over the last 100 years compared to the long term (last ∼ 1500 to 3000 yrs) average. Infilling during the Holocene is not spatially uniform, with preferential deposition occurring within the now submerged palaeochannels of the Brisbane and Pine rivers. We suggest that modern turbidity regimes in Moreton Bay are the result of the compounded effect of both a historical increase in fine sediment supply and a rapid decline in the effective storage capacity of the basin.

  19. Stream quality in a small urbanised catchment

    International Nuclear Information System (INIS)

    River-length patterns in the chemistry and biology of the Charlton Brook, an unclassified watercourse in Sheffield, England, have been examined. Five sampling sites for macroinvertebrates and pollutant analysis were used, in conjunction with Environment Agency's General Quality Assessment (GQA) methodologies and hydraulic analysis of the catchment. Sites were strategically located to account for the tributaries and the brook downstream of their confluence, to assess the potential impact from surface water outfalls (SWOs). Variations in GQA parameters indicate a significant drop in quality downstream of the SWOs that discharge to the study watercourse, with a marked drop in biological diversity noted at the onset of urbanisation. The decline in biological quality however is greater than that suggested by physicochemical analysis alone. There was a significant inverse relationship between impermeable area and biological diversity. Analysis of polycyclic aromatic hydrocarbons (PAHs) and trace metals in sediment from the watercourse showed significant yet irregular variations between sites. The potential toxicity of instream metal concentrations was determined using cumulative criterion unit (CCU) scores, which highlighted cadmium, copper and lead as the major sources of potential chronic instream toxicity. The threshold for likely harm to aquatic life is exceeded at all sites. In the absence of different physical characteristics, comparisons of the chemical and biological data indicate that the benthic macroinvertebrate population of such watercourses are adversely affected by the stormwater inputs

  20. Hypothesis testing in the Maimai Catchments, Westland

    International Nuclear Information System (INIS)

    Seven experiments were carried out on the Maimai Catchments, Westland, to test assumptions about the nature of unsaturated zone waters flows in this humid environment. Hypotheses tested were: 1) that the deuterium (D) content of base flow water sources in small streams are constant at any given time, 2) that different soil moisture sampling methods give the same D contents, 3) that throughfall has the same D content as rainfall, 4) that saturation overland flow is mainly composed of current event rainfall, 5) that macropores are not connected into pipe networks, 6) that the underlying substrate (Old Man Gravel conglomerate) does not deliver water to the stream during rainfall events, and 7) that different near-stream water sources have the same D contents at a given time. Over 570 samples were collected of which 300 were analysed for deuterium in 1992-1993. This report gives the background, rationale, methods and brief results of the experiments. The results will be integrated with other measurements and written up in one or more papers for journal publication. (author). 18 refs.; 4 figs.; 1 tab

  1. Comparison of subsurface connectivity in Alpine headwater catchments

    Science.gov (United States)

    Zuecco, Giulia; Rinderer, Michael; van Meerveld, Ilja; Penna, Daniele; Borga, Marco

    2016-04-01

    Saturation at the soil-bedrock interface or the rise of shallow groundwater into more permeable soil layers results in subsurface stormflow and can lead to hillslope-stream connectivity. Despite the importance of subsurface connectivity for streamflow and streamwater chemistry, the factors controlling its spatial and temporal variability are still poorly understood. This study takes advantage of networks of spatially-distributed piezometers in five small (piezometers in the 14 and 3.3 ha catchments in the Italian Dolomites, and for four years from spring to fall in 7-8 piezometers in three piezometers (nodes). A node was considered to be connected to the stream when shallow groundwater was observed in the piezometer and it was connected by the edges to the stream. Weights were given to each piezometer based on Thiessen polygons to determine the area of the catchment that was connected to the stream. For the Swiss pre-alpine catchments the duration that nodes were connected to the stream was significantly correlated to the local and upslope site characteristics, such as the topographic wetness index, local slope and curvature. For the dolomitic catchment with the largest riparian zone, the time that nodes were connected to the stream was correlated with downslope site characteristics, such as the vertical distance to the nearest stream. The temporal changes in the area of the catchment that was connected to the stream reflected the streamflow dynamics for all catchments. Subsurface connectivity increased during rainfall events but there was a short delay compared to streamflow, suggesting that other processes (e.g. direct channel precipitation, runoff from near stream saturated areas) contributed to streamflow at the beginning of the event. Groundwater levels declined later and slower than streamflow, resulting in complex but mainly anti-clockwise hysteretic relations between streamflow and the area that was connected to the stream. Threshold-like relations between

  2. Guiding soil conservation strategy in headwater mediterranean catchments

    Science.gov (United States)

    Ben Slimane, Abir; Raclot, Damien; Evrard, Olivier; Sanaa, Mustapha; Lefèvre, Irène; Le Bissonnais, Yves

    2016-04-01

    Reservoir siltation due to water erosion is an important environmental issue in Mediterranean countries where storage of clear surface water is crucial for their economic and agricultural development. In order to reduce water erosion, this study aimed to design a methodology for guiding the implementation of efficient conservation strategies by identifying the dominant sediment sources in Mediterranean context. To this end, a fingerprinting method was combined with long-term field monitoring of catchment sediment yield in five headwater catchments (0.1-10 km2) equipped with a small reservoir between 1990 and 1995. The five catchments were chosen to cover the large diversity of environmental conditions found along the Tunisian Ridge and in the Cape Bon region. The fingerprinting techniques based on measurements of cesium-137 and Total Organic Carbon within the catchments and in reservoir sediment deposits successfully identified the contribution of rill/interrill and gully/channel erosion to sediment yield at the outlet of five small headwater catchments during the last 15-20 years. Results showed the very large variability of erosion processes among the selected catchments, with rill/interrill erosion contributions to sediment accumulated in outlet reservoirs ranging from 20 to 80%. Overall, rill/interrill erosion was the dominant process controlling reservoir siltation in three catchments whereas gully/channel erosion dominated in the other two catchments. This demonstrates that the dominant erosion process in the Mediterranean regions highly depends on the local environmental context. The lowest rill/interrill erosion contribution (2.2 Mg ha-1 yr-1) in the five catchments remained significantly higher than the tolerable soil loss indicating the severe levels reached by soil erosion along the Tunisian Ridge and in the Cape Bon region. This study also showed that although the implementation of improved topsoil management measures greatly reduced rill

  3. Basin-scale characterization of river hydromorphology by map derived information: A case study on the Red River (Sông Hông), Vietnam

    Science.gov (United States)

    Schmitt, R. J.; Bizzi, S.; Castelletti, A.

    2012-12-01

    The understanding of river hydromorphological processes has been recognized in the last decades as a priority of modern catchment management, since fluvial geomorphic processes shape physical habitat, affect river infrastructures and influence freshwater ecological processes. Characterization of river hydromorphological features is commonly location specific and highly demanding in terms of field-works, resource and expertise required. Therefore, its routine application at regional or national scales, although an urgent need of catchment management, is infeasible at present. Recently available high-resolution data, such as DEM or LIDAR, opens up novel potential for basin-wide analysis of fluvial processes at limited effort and cost. Specifically, in this study we assess the feasibility of characterizing river hydromorphology from specific map derived geomorphic controls namely: channel gradient, bankfull flow, specific stream power, and degree of channel confinement. The river network, extracted from a digital elevation model and validated with available network shape-files and optical satellite imagery, available flow gauging stations and GIS processing allow producing continuous values of geomorphic drivers defined over given length segments at catchment or regional scales. This generic framework was applied to the Red River (Sông Hông) basin, the second largest basin (87,800 km2) in Vietnam. Besides its economic importance, the river since few years is experiencing severe river bed incisions due to the building of new dams in the upstream part of the catchment and sand mining in the surrounding of the capital city Hanoi. In this context, characterized by an high developing rate, current efforts to increase water productivity by infrastructure and management measures require a thorough understanding of fluvial system and, in particular, of the basin-wide river hydromorphology. The framework proposed has allowed producing high-dimensional samples of spatially

  4. Assessment of climate change impact on hydrological extremes in two source regions of the Nile River Basin

    Directory of Open Access Journals (Sweden)

    M. T. Taye

    2011-01-01

    Full Text Available The potential impact of climate change was investigated on the hydrological extremes of Nyando River and Lake Tana catchments, which are located in two source regions of the Nile River basin. Climate change scenarios were developed for rainfall and potential evapotranspiration (ETo, considering 17 General Circulation Model (GCM simulations to better understand the range of possible future change. They were constructed by transferring the extracted climate change signals to the observed series using a frequency perturbation downscaling approach, which accounts for the changes in rainfall extremes. Projected changes under two future SRES emission scenarios A1B and B1 for the 2050s were considered. Two conceptual hydrological models were calibrated and used for the impact assessment. Their difference in simulating the flows under future climate scenarios was also investigated.

    The results reveal increasing mean runoff and extreme peak flows for Nyando catchment for the 2050s while unclear trend is observed for Lake Tana catchment for mean volumes and high/low flows. The hydrological models for Lake Tana catchment, however, performed better in simulating the hydrological regimes than for Nyando, which obviously also induces a difference in the reliability of the extreme future projections for both catchments. The unclear impact result for Lake Tana catchment implies that the GCM uncertainty is more important for explaining the unclear trend than the hydrological models uncertainty. Nevertheless, to have a better understanding of future impact, hydrological models need to be verified for their credibility of simulating extreme flows.

  5. Erosion process contribution to sediment yield before and after the establishment of exotic forest: Waipaoa catchment, New Zealand

    Science.gov (United States)

    Marden, M.; Herzig, A.; Basher, L.

    2014-12-01

    The East Coast region of the North Island, New Zealand, is well known for its severe erosion, high sediment yields, flooding, and sedimentation following extensive deforestation of its indigenous forest during the late 19th and early 20th centuries. For six decades thereafter, extensive grazing (cattle and sheep) left a legacy of highly degraded hill country, much of which has since been retired and planted in exotic forest, primarily to control erosion. Previous studies have documented the extent of gully erosion, calculated erosion rates and sediment delivery from gullies to the channel load within the study basin, but this has not been quantified for the more extensive mass movement processes including slump, earthflow, and shallow landslides. Additionally, the magnitude of the effect of reforestation on sediment load at subcatchment level and, ultimately on sediment yield at catchment scale, for this combination of erosion processes and, over the time frame of a rotation of exotic forest (~ 28 years), is unknown. For a 140-km2 study basin located in the headwaters of the 2150 km2 Waipaoa River catchment, we establish the contribution to basin sediment load by each of these erosion processes, spanning a ~ 50-year period that includes a ~ 28-year reforestation effort. We quantified the effectiveness of exotic reforestation as an erosion control strategy by using the mapped extent of each of the erosion processes before planting (i.e. 1939-59), as the benchmark against which any subsequent change in eroded area (km2) was measured. Based on this, process-based erosion load was calculated for the pre-planting period (1939-59), for the period 10 years after planting commenced (1960-69), and again for the period 1970-88, which marked the completion of planting within the study basin. The study basin sediment load is then expressed as a proportion (percentage) of the measured sediment yield (Mt y- 1) of the wider Waipaoa River catchment. The net area affected by

  6. Isotope hydrology study of Kalamos region (Attiki) and of the Assopos river basin

    International Nuclear Information System (INIS)

    The isotopic composition of the water was used to determine the mechanism of recharge of the Assopos river basin and that of the Kalamos springs issuing brackish water near the coast. The results of the study permitted the catchment of the water before its salinization. A quantity of 73000 m3 per day is now pumped and used as additional drinkable water for the major area of Athens covering about the 1/6 of the corresponding mean daily consumption. (T.A.)

  7. Trends in timing and magnitude of flow in the Upper Indus Basin

    OpenAIRE

    M. Sharif; Archer, D.R.; Fowler, H J; N. Forsythe

    2012-01-01

    River flow is a reflection of the input of moisture and its transformation in storage and transmission over the catchment. In the Upper Indus Basin (UIB), since high altitude climate measurement and observations of glacier mass balance are weak or absent, analysis of trends in magnitude and timing in river flow provides a window on trends and fluctuations in climate and glacier outflow. Trend analysis is carried out using a Mann-Kendall nonparametric trend test on records extending from ...

  8. Trends in timing and magnitude of flow in the Upper Indus Basin

    OpenAIRE

    M. Sharif; Archer, D.R.; Fowler, H J; N. Forsythe

    2013-01-01

    River flow is a reflection of the input of moisture and its transformation in storage and transmission over the catchment. In the Upper Indus Basin (UIB), since high-altitude climate measurement and observations of glacier mass balance are weak or absent, analysis of trends in magnitude and timing in river flow provides a window on trends and fluctuations in climate and glacier outflow. Trend analysis is carried out using a Mann–Kendall nonparametric trend test on records ex...

  9. Impact Assessment and monitoring programme in the Subarnarekha river basin (INDIA)

    OpenAIRE

    Lemiere, Bruno; Billaud, Pierre; Roy, Stéphane; Négrel, Philippe; Brochot, Stéphane; Machard De Gramont, Hubert

    2011-01-01

    Environmental impact assessment (EIA) is the main instrument used by Governments to ensure that environmental management in companies is in conformity with society's environmental objectives. Despite its project-specific applications, the scope can be widened to a regional scale (e.g. a river basin) in view of assessing the cumulative effects of multiple industrial activities on the environment and human living conditions. Within the Subarnarekha catchment, mines, processing plants and copper...

  10. Flash flood hazard mapping: a pilot case study in Xiapu River Basin, China

    OpenAIRE

    Da-wei Zhang; Jin Quan; Hong-bin Zhang; Fan Wang; Hong Wang; Xiao-yan He

    2015-01-01

    Flash flood hazard mapping is a supporting component of non-structural measures for flash flood prevention. Pilot case studies are necessary to develop more practicable methods for the technical support systems of flash flood hazard mapping. In this study, the headwater catchment of the Xiapu River Basin in central China was selected as a pilot study area for flash flood hazard mapping. A conceptual distributed hydrological model was developed for flood calculation based on the framework of t...

  11. Water budget and its variation in Hutuo River basin predicted with the VIP ecohydrological model

    OpenAIRE

    Huang, F; Mo, X.

    2015-01-01

    Accurate assessment of water budgets is important to water resources management and sustainable development in catchments. Here the VIP (Vegetation Interface Processes) ecohydrological model is used to estimate the water budget and its influence factors in Hutuo River basin, China. The model runs from 1956 to 2010 with a spatial resolution of 1 km, utilizing remotely sensed LAI data of MODIS. During the study period the canopy transpiration takes up 58% of evapotranspiration over the whole ca...

  12. Rainfall-runoff modelling of water resources in the upper Senegal River basin

    OpenAIRE

    Bodian, A.; Dezetter, Alain; Dacosta, H.

    2016-01-01

    The streamflow series for the upstream basin of the Senegal River is marked by considerable gaps. The objective of this article is to simulate and extend hydrological data, using the GR2M rainfall-runoff model. A sensitivity analysis of the model to rainfall and water holding capacity input data was performed. This analysis was performed after calculating catchment rainfall, mean potential evapotranspiration, and maximum, minimum and mean water holding capacity. The best combination of input ...

  13. Decentralised governance of wetland resources in the Lake Victoria Basin of Uganda

    OpenAIRE

    Nakiyemba Were, Alice; Isabirye, Moses; Poesen, Jean; Maertens, Miet; Deckers, Seppe; Mathijs, Erik

    2013-01-01

    Recent studies on decentralized wetland governance in Uganda have focused mainly on the relationship between central and local governments. Less attention has been given to the relationship between agricultural systems, local governments, and water bodies. This study aims at assessing decentralized wetlands governance in the upper river Rwizi and Iguluibi micro catchments, Lake Victoria Basin Uganda, in relation to farming practices. Qualitative and quantitative methods were used to provide a...

  14. Comparative assessment of predictions in ungauged basins – Part 3: Runoff signatures in Austria

    OpenAIRE

    Blöschl, G.; M. Sivapalan; G. Laaha; J. L. Salinas; M. Rogger; Parajka, J.; Viglione, A.

    2013-01-01

    In a three-part paper we assess the performance of runoff predictions in ungauged basins in a comparative way. While Parajka et al. (2013) and Salinas et al. (2013) assess the regionalisation of hydrographs and hydrological extremes through a literature review, in this paper we assess prediction of a range of runoff signatures for a consistent dataset. Daily runoff time series are predicted for 213 catchments in Austria by a regionalised rainfall–runoff model and by Top-Kriging, a geosta...

  15. Hydrological drought severity explained by climate and catchment characteristics

    Science.gov (United States)

    Van Loon, A. F.; Laaha, G.

    2015-07-01

    Impacts of a drought are generally dependent on the severity of the hydrological drought event, which can be expressed by streamflow drought duration or deficit volume. For prediction and the selection of drought sensitive regions, it is crucial to know how streamflow drought severity relates to climate and catchment characteristics. In this study we investigated controls on drought severity based on a comprehensive Austrian dataset consisting of 44 catchments with long time series of hydrometeorological data (on average around 50 year) and information on a large number of physiographic catchment characteristics. Drought analysis was performed with the variable threshold level method and various statistical tools were applied, i.e. bivariate correlation analysis, heatmaps, linear models based on multiple regression, varying slope models, and automatic stepwise regression. Results indicate that streamflow drought duration is primarily controlled by storage, quantified by the Base Flow Index or by a combination of catchment characteristics related to catchment storage and release, e.g. geology and land use. Additionally, the duration of dry spells in precipitation is important for streamflow drought duration. Hydrological drought deficit, however, is governed by average catchment wetness (represented by mean annual precipitation) and elevation (reflecting seasonal storage in the snow pack and glaciers). Our conclusion is that both drought duration and deficit are governed by a combination of climate and catchment control, but not in a similar way. Besides meteorological forcing, storage is important; storage in soils, aquifers, lakes, etc. influences drought duration and seasonal storage in snow and glaciers influences drought deficit. Consequently, the spatial variation of hydrological drought severity is highly dependent on terrestrial hydrological processes.

  16. Correlation of Fish and Benthic Macroinvertebrate Communities With Multi-scale Environmental Descriptors in Wadeable Streams of the Yukon River Basin

    Science.gov (United States)

    Bailey, J. L.; Bailey, R. C.; Scott, R. J.

    2005-05-01

    We sampled fish and benthic macroinvertebrates at thirty wadeable stream sites in the Yukon River basin in Yukon Territory, Canada during July, 2004, to establish reference conditions in Yukon River basin stream communities. We also measured water quality (eg. temperature, dissolved oxygen, conductivity, pH), stream flow, substrate characteristics and riparian vegetation at each site. Water samples from each site were subsequently analyzed for nutrients and metals. In addition, catchment area, catchment perimeter, catchment land cover, distance of each site to major water bodies and stream barriers were determined through Geographic Information System and satellite photography analysis. Fish and benthic macroinvertebrate community structures and their relationships with the multi-scale description of the stream environment were quantified with non-metric multidimensional scaling, principal component analysis, and correlation analysis.

  17. Explicit simulations of stream networks to guide hydrological modelling in ungauged basins

    Directory of Open Access Journals (Sweden)

    S. Stoll

    2010-01-01

    Full Text Available Rainfall-runoff modelling in ungauged basins is still one of the greatest challenges in recent hydrological research. The lack of discharge data necessitates the establishment of new innovative approaches to guide hydrological modelling in ungauged basins. Besides the transfer of calibrated parameters from similar gauged catchments, the application of distributed data as a hydrological response in addition to discharge seems to be promising. A new approach for model and parameter evaluation based on explicit simulation of the spatial stream network was tested in four different catchments in Germany. In a first step, spatial explicit modelling of stream networks was performed using a simplified version of the process-based model Hill-Vi together with regional climate normals. The simulated networks were compared to mapped stream networks and their degree of spatial agreement was evaluated. Significant differences between good and poor simulations could be distinguished and the corresponding parameter sets relate well with the hydrogeological properties of the catchments. The optimized parameters were subsequently used to simulate daily discharge using an observed time series of precipitation and air temperature. The performance was evaluated against observed discharge and water balance. This approach shows some promising results but also some limitations. Although the model's parsimonious model structure should to be further improved regarding discharge recession and evapotranspiration, the performance was similar to the regionalisation methods. Stream network modelling, which has minimal data requirements, seems to be a reasonable alternative for model development and parameter evaluation in ungauged basins.

  18. Regional Flood Frequency Analysis Utilizing L-Moments: A Case Study of Narmada Basin

    Directory of Open Access Journals (Sweden)

    Amit Dubey

    2014-02-01

    Full Text Available Accurate estimation of flood frequency is needed for the designing of various hydraulic structures such as dam, spillways, barrage etc. Different approaches were presented which uses the conventional moments to extract order statistics such as mean, standard deviation, skewness, kurtosis. Due to problems arising from data quality, such as short record and outliers, conventional moments are problematic. Hosking (1990 developed L-Moments which are linear combinations of order statistics. The main advantage of L-Moments over conventional moments is that they suffer less from the effects of sampling variability. They are more robust to outliers and virtually unbiased for small samples. In this study the L-Moments based method of Regional Flood Frequency Analysis is mentioned and Narmada Basin is considered as a case. The L-Moments have been used for parameter estimation of Generalized Extreme Value (GEV distribution. Regional flood frequency relationship for the chosen basin is developed utilizing GEV distribution. A relationship between mean annual flood and catchment area is obtained which is further employed to generate Regional Flood Formula for ungauged catchment of Narmada Basin. The developed Regional flood formula is used for T-Year return period flood estimation, knowing only one parameter i.e. catchment area of ungauged watershed.

  19. Assessment of hydric balance through climatic variables, in the Cazones River Basin, Veracruz, Mexico

    Directory of Open Access Journals (Sweden)

    Eduardo Santillán Gutiérrez

    2014-09-01

    Full Text Available The hydrologic regime and the water catchment capacity of a hydrographic basin depend on the temporal and spatial variation patterns of climatic variables and on the physiographic characteristics of the watershed. In certain regions, where the availability of water depends on the catchment capacity of the watershed, the utilization of effective methods such as the hydric balance has become more frequently used because it enables an estimate of the hydrologic regime, the catchment capacity, and the water flows. It also enables an estimate of the hydrologic processes and the period in which they occurred. In the present work, assessments of the Climatic Hydric Balance (CHB and of potential evapotranspiration were performed in the Cazones river basin. The calculations followed the Thornthwaite and Mather method based on climatic variables such as temperature and precipitation during the period from 1981 to 2010. As a result of these assessments, it was found that the excess layer of water and the annual runoff were 638.63 mm and 637.02 mm, respectively. Further, the work identified the months that comprise the humid and dry periods, the regime of the climatic variables, and surpluses and deficits of water in the basin during an annual cycle.

  20. Modelling nitrogen and phosphorus loads in a Mediterranean river catchment (La Tordera, NE Spain

    Directory of Open Access Journals (Sweden)

    F. Caille

    2012-08-01

    Full Text Available Human activities have resulted in increased nutrient levels in many rivers all over Europe. Sustainable management of river basins demands an assessment of the causes and consequences of human alteration of nutrient flows, together with an evaluation of management options. In the context of an integrated and interdisciplinary environmental assessment (IEA of nutrient flows, we present and discuss the application of the nutrient emission model MONERIS (MOdelling Nutrient Emissions into River Systems to the Catalan river basin, La Tordera (north-east Spain, for the period 1996–2002. After a successful calibration and verification process (Nash-Sutcliffe efficiencies E=0.85 for phosphorus and E=0.86 for nitrogen, the application of the model MONERIS proved to be useful in estimating nutrient loads. Crucial for model calibration, in-stream retention was estimated to be about 50 % of nutrient emissions on an annual basis. Through this process, we identified the importance of point sources for phosphorus emissions (about 94% for 1996–2002, and diffuse sources, especially inputs via groundwater, for nitrogen emissions (about 31% for 1996–2002. Despite hurdles related to model structure, observed loads, and input data encountered during the modelling process, MONERIS provided a good representation of the major interannual and spatial patterns in nutrient emissions. An analysis of the model uncertainty and sensitivity to input data indicates that the model MONERIS, even in data-starved Mediterranean catchments, may be profitably used by water managers for evaluating quantitative nutrient emission scenarios for the purpose of managing river basins. As an example of scenario modelling, an analysis of the changes in nutrient emissions through two different future scenarios allowed the identification of a set of relevant measures to reduce nutrient loads.

  1. Catchment systems science and management: from evidence to resilient landscapes

    Science.gov (United States)

    Quinn, Paul

    2014-05-01

    There is an urgent need to reassess both the scientific understanding and the policy making approaches taken to manage flooding, water scarcity and pollution in intensively utilised catchments. Many European catchments have been heavily modified and natural systems have largely disappeared. However, working with natural processes must still be at the core of any future management strategy. Many catchments have greatly reduced infiltration rates and buffering capacity and this process needs to be reversed. An interventionist and holistic approach to managing water quantity and quality at the catchment scale is urgently required through the active manipulation of natural flow processes. Both quantitative (field experiments and modelling) and qualitative evidence (local knowledge) is required to demonstrate that catchment have become 'unhealthy'. For example, dense networks of low cost instrumentation could provide this multiscale evidence and, coupled with stakeholder knowledge, build a comprehensive understanding of whole system function. Proactive Catchment System Management is an interventionist approach to altering the catchment scale runoff regime through the manipulation of landscape scale hydrological flow pathways. Many of the changes to hydrological processes cannot be detected at the catchment scale as the primary causes of flooding and pollution. Evidence shows it is the land cover and the soil that are paramount to any change. Local evidence shows us that intense agricultural practices reduce the infiltration capacity through soil degradation. The intrinsic buffering capacity has also been lost across the landscape. The emerging hydrological process is one in which the whole system responds too quickly (driven by near surface and overland flow processes). The bulk of the soil matrix is bypassed during storm events and there is little or no buffering capacity in the riparian areas or in headwater catchments. The prospect of lower intensity farming rates is

  2. Long-term and short-term erosion rates in river catchments of the Rhenish Massif and the Black Forest, Germany

    Science.gov (United States)

    Meyer, H.; Hetzel, R.; Strauss, H.

    2007-12-01

    We constrained long-term erosion rates from the concentration of cosmogenic 10Be in stream sediments in order to quantify the Late Quaternary denudation history of mountain ranges in central Europe. Four different catchments in Germany, ranging in size from 8 to 379 km2 were investigated. Two of them, the Aabach and Möhne catchments drain predominantly low-grade Paleozoic metasediments. The other two, the Gutach and Acher catchments in the Black Forest are situated in Late Paleozoic granites. Erosion rates derived from the 10Be concentrations range from 29 to 86 mm/ka in the Rhenish Massif and from 26 to 91 mm/ka in the Black Forest. These spatially-averaged erosion rates integrate over the past 7 to 23 ka. Central to our investigation are questions concerning the relative importance of lithology and catchment relief on long-term erosion rates. Short-term erosion rates for all catchments were quantified by combining the amounts of suspended and dissolved loads in water samples with water discharge data and basin area. By analyzing the stable isotope signatures δ18O of river water and δ13C of dissolved anorganic carbon and by taking into account the precipitation and evaporation we corrected the dissolved load for organic, atmospheric and anthropogenic inputs. The preliminary short-term erosion rates vary between 9 and 33 mm/ka and are only about one third of the erosion rates derived from 10Be. The short-term erosion rates are complemented by erosion rates derived from the volume of sediment stored behind reservoirs of known age. These erosion rates range from 2 to 13 mm/ka and are lower than the erosion rates derived from river loads, as they do not take into account the dissolved load. Furthermore, we focused on dependence of lithology and land use on short-term erosion rates.

  3. High-resolution monitoring of stormwater quality in an urbanising catchment in the United Kingdom during the 2013/2014 winter storms

    Science.gov (United States)

    McGrane, S. J.; Hutchins, M. G.; Kjeldsen, T. R.; Miller, J. D.; Bussi, G.; Loewenthal, M.

    2015-12-01

    Urban areas are widely recognised as a key source of contaminants entering our freshwater systems, yet in spite of this, our understanding of stormwater quality dynamics remains limited. The development of in-situ, high-resolution monitoring equipment has revolutionised our capability to capture flow and water quality data at a sub-hourly resolution, enabling us to potentially enhance our understanding of hydrochemical variations from contrasting landscapes during storm events. During the winter of 2013/2014, the United Kingdom experienced a succession of intense storm events, where the south of the country experienced 200% of the average rainfall, resulting in widespread flooding across the Thames basin. We applied high-frequency (15 minute resolution) water quality monitoring across ten contrasting subcatchments (including rural, urban and mixed land-use catchments), seeking to classify the disparity in water quality conditions both within- and between events. Rural catchments increasingly behave like "urban" catchments as soils wet up and become increasingly responsive to subsequent events, however water quality response during the winter months remains limited. By contrast, increasingly urban catchments yield greater contaminant loads during events, and pre-event baseline chemistry highlights a resupply source in dense urban catchments. Wastewater treatment plants were shown to dominate baseline chemistry during low-flow events but also yield a considerable impact on stormwater outputs during peak-flow events, as hydraulic push results in the outflow of untreated solid wastes into the river system. Results are discussed in the context of water quality policy; urban growth scenarios and BMP for stormwater runoff in contrasting landscapes.

  4. River Suspended Sediment and Particulate Organic Carbon Transport in Two Montane Catchments in the Luquillo Critical Zone Observatory of Puerto Rico over 25 years: 1989 to 2014

    Science.gov (United States)

    Clark, K. E.; Plante, A. F.; Willenbring, J. K.; Jerolmack, D. J.; Gonzalez, G.; Stallard, R. F.; Murphy, S. F.; Vann, D. R.; Leon, M.; McDowell, W. H.

    2015-12-01

    Physical erosion in mountain catchments mobilizes large amounts of sediment, while exporting carbon and nutrients from forest ecosystems. This study expands from previous studies quantifying river suspended sediment and particulate organic carbon loads in the Luquillo Critical Zone Observatory, in Puerto Rico. We evaluate the influences on river suspended load due to i) underlying basin geology, ii) hillslope debris and biomass supply, and iii) hurricanes and large storms. In the Mameyes and Icacos catchments of the Luquillo Mountains, we estimate suspended sediment and particulate organic carbon yields over a 25-year period using streamflow discharge determined from stage measurements at 15-intervals, with estimates of discharge replacing gaps in data, and over 3000 suspended sediment samples. We estimate variation in suspended sediment loads over time, and examine variation in particulate organic carbon loads. Mass spectrometry was used to determine organic carbon concentrations. We confirm that higher suspended sediment fluxes occurred i) in the highly weathered quartz diorite catchment rather than the predominantly volcaniclastic catchment, ii) on the rising limb of the hydrograph once a threshold discharge had been reached, and iii) during hurricanes and other storm events, and we explore these influences on particulate organic carbon transport. Transport of suspended sediment and particulate organic carbon in the rivers shows considerable hysteresis, and we evaluate the extent to which hysteresis affects particulate fluxes over time and between catchments. Because particulate organic carbon is derived from the critical zone and transported during high flow, our research highlights the role of major tropical storms in controlling carbon storage in the critical zone and the coastal ocean.

  5. Modelling soil erosion and associated sediment yield for small headwater catchments of the Daugava spillway valley, Latvia

    Science.gov (United States)

    Soms, Juris

    2015-04-01

    The accelerated soil erosion by water and associated fine sediment transfer in river catchments has various negative environmental as well as economic implications in many EU countries. Hence, the scientific community had recognized and ranked soil erosion among other environmental problems. Moreover, these matters might worsen in the near future in the countries of the Baltic Region, e.g. Latvia considering the predicted climate changes - more precisely, the increase in precipitation and shortening of return periods of extreme rainfall events, which in their turn will enable formation of surface runoff, erosion and increase of sediment delivery to receiving streams. Thereby it is essential to carry out studies focused on these issues in order to obtain reliable data in terms of both scientific and applied aims, e.g. environmental protection and sustainable management of soils as well as water resources. During the past decades, many of such studies of soil erosion had focused on the application of modelling techniques implemented in a GIS environment, allowing indirectly to estimate the potential soil losses and to quantify related sediment yield. According to research results published in the scientific literature, this approach currently is widely used all over the world, and most of these studies are based on the USLE model and its revised and modified versions. Considering that, the aim of this research was to estimate soil erosion rates and sediment transport under different hydro-climatic conditions in south-eastern Latvia by application of GIS-based modelling. For research purposes, empirical RUSLE model and ArcGIS software were applied, and five headwater catchments were chosen as model territories. The selected catchments with different land use are located in the Daugava spillway valley, which belongs to the upper Daugava River drainage basin. Considering lithological diversity of Quaternary deposits, a variety of soils can be identified, i.e., Stagnic

  6. Deriving N-year discharges in small catchments

    Science.gov (United States)

    Ledvinka, Ondrej; Bohac, Milon

    2016-04-01

    Maximum discharges with the return period of 100 years (Q100) belong to basic hydrological data that are derived and provided for any profile of the river network by the Czech Hydrometeorological Institute (CHMI). However, as regards small catchments, the determination of these characteristics is largely subjective and thus it is rather performed by comparing the results of several methods. The first approach is to extrapolate the three parameters of maximum peak discharges (average Qmax, coefficient of variation Cvmax, Q100) from water-gauging stations to selected unobserved profiles (using regression relationships and regularities at the confluence points). For this purpose, the so-called program Budsez is utilized. During this process, the physical-geographical (PG) features, rainfall data and other information about catchments are considered, based on which the parameters of theoretical distributions of N-year discharges are optimized. For smaller catchments the relationships between the 100-year specific runoff q100 and the catchment area and other PG characteristics are used that are determined in a GIS environment with the extension AGPosudek. In this innovative method, besides many other PG characteristics, especially the average value of CN and N-year maximum daily precipitation are taken into account when computing Q100. In the older methodologies, Q100 is based on the average slope of the stream and the average slope of the catchment. The values of Q100 are then corrected according to the percentage of forested areas and the catchment shape. Hydrologists compare the values of Q100 coming from different approaches in a logarithmic graph (q100 against area) for the particular catchment or its analogon. The final value is determined with respect to experience and previously issued values. The remaining N-year discharges are usually assessed through the ratio QN/Q100 from the nearest water-gauging station or the closest profile where these ratios were

  7. Carbon redistribution by erosion processes in an intensively disturbed catchment

    Science.gov (United States)

    Boix-Fayos, Carolina; Martínez-Mena, María; Pérez Cutillas, Pedro; de Vente, Joris; Barberá, Gonzalo G.; Mosch, Wouter; Navarro Cano, Jose Antonio; Gaspar, Leticia; Navas, Ana

    2016-04-01

    Understanding how organic carbon moves with sediments along the fluvial system is crucial to close catchment scale carbon budgets. Especially challenging is the analysis of organic carbon dynamics during fluvial transport in heterogeneous, fragile and disturbed environments with ephemeral and intense hydrological pulses, typical of Mediterranean conditions. This paper explores the catchment scale organic carbon redistribution by lateral flows in extreme Mediterranean environmental conditions from a geomorphological perspective. The study area is a catchment (Cárcavo) in SE Spain with a semiarid climate, erodible lithologies, shallow soils, and highly disturbed by agricultural terraces, land levelling, reforestations and construction of check-dams. To increase understanding of erosion induced catchment scale organic carbon redistribution, we studied the subcatchments of 8 check-dams distributed along the catchment main channel in detail. We determined 137Cs, physicochemical characteristics and organic carbon pools of soils and sediments deposited behind each check-dam, performed spatial analysis of properties of the catchment and buffer areas around check-dams, and carried out geomorphological analysis of the slope-channel connections. Soils showed very low Total Organic Carbon (TOC) values oscillating between 15.2 and 4.4 g Kg-1 for forest and agricultural soils, respectively. Sediments mobilized by erosion were poor in TOC compared to the eroded (forest) soils (6.6±0.7 g Kg-1), and the redistribution of organic carbon through the catchment, especially of the Mineral Associated Organic Carbon (MAC) pool, showed the same pattern as clay particles and 137Cs. The TOC erosion rates (0.031±0.03 Mg ha-1 y-1) were comparable to others reported for subhumid Mediterranean catchments and to those modelled worldwide for pasture land. Those lateral fluxes were equivalent to 10.4 % of the TOC stock from the topsoil at the moment of the check-dam construction and

  8. Nitrogen attenuation along delivery pathways in agricultural catchments

    Science.gov (United States)

    McAleer, Eoin; Mellander, Per-Erik; Coxon, Catherine; Richards, Karl G.

    2014-05-01

    Hillslope hydrologic systems and in particular near-stream saturated zones are active sites of nitrogen (N) biogeochemical dynamics. The efficiency of N removal and the ratio of reaction products (nitrous oxide and dinitrogen) in groundwater is highly variable and depends upon aquifer hydrology, mineralogy, dissolved oxygen, energy sources and redox chemistry. There are large uncertainties in the closing of N budgets in agricultural catchments. Spatial and temporal variability in groundwater physico-chemistry, catchment hydrology and land-use gives rise to hotspots and hot moments of N attenuation. In addition the production, consumption and movement of denitrification products remains poorly understood. The focus of this study is to develop a holistic understanding of N dynamics in groundwater as it moves from the top of the hillslope to the stream. This includes saturated groundwater flow, exchange at the groundwater-surface water interface and hyporheic zone flow. This project is being undertaken in two ca. 10km2 Irish catchments, characterised by permeable soils. One catchment is dominated by arable land overlying slate bedrock and the other by grassland overlying sandstone. Multi-level monitoring wells have been installed at the upslope, midslope and bottom of each hillslope. The piezometers are screened to intercept the subsoil, weathered bedrock and competent bedrock zones. Groundwater samples for nitrate (NO3-N) nitrite (NO2-N), ammonium (NH4-N) and total nitrogen are collected on a monthly basis while dissolved gas concentrations are collected seasonally. Groundwater NO3-N profiles from monitoring data to date in both catchments differ markedly. Although the two catchments had similar 3 year mean concentrations of 6.89 mg/L (arable) and 6.24 mg/L (grassland), the grassland catchment had higher spatial and temporal variation. The arable catchment showed relatively homogenous NO3-N concentrations in all layers and zones (range: 1.2 - 12.13 mg/L, SD = 1.60 mg

  9. The Influence of temporal sampling regime on the WFD classification of catchments within the Eden Demonstration Test Catchment Project

    Science.gov (United States)

    Jonczyk, Jennine; Haygarth, Phil; Quinn, Paul; Reaney, Sim

    2014-05-01

    A high temporal resolution data set from the Eden Demonstration Test Catchment (DTC) project is used to investigate the processes causing pollution and the influence of temporal sampling regime on the WFD classification of three catchments. This data highlights WFD standards may not be fit for purpose. The Eden DTC project is part of a UK government-funded project designed to provide robust evidence regarding how diffuse pollution can be cost-effectively controlled to improve and maintain water quality in rural river catchments. The impact of multiple water quality parameters on ecosystems and sustainable food production are being studied at the catchment scale. Three focus catchments approximately 10 km2 each, have been selected to represent the different farming practices and geophysical characteristics across the Eden catchment, Northern England. A field experimental programme has been designed to monitor the dynamics of agricultural diffuse pollution at multiple scales using state of the art sensors providing continuous real time data. The data set, which includes Total Phosphorus and Total Reactive Phosphorus, Nitrate, Ammonium, pH, Conductivity, Turbidity and Chlorophyll a reveals the frequency and duration of nutrient concentration target exceedance which arises from the prevalence of storm events of increasing magnitude. This data set is sub-sampled at different time intervals to explore how different sampling regimes affects our understanding of nutrient dynamics and the ramification of the different regimes to WFD chemical status. This presentation seeks to identify an optimum temporal resolution of data for effective catchment management and to question the usefulness of the WFD status metric for determining health of a system. Criteria based on high frequency short duration events needs to be accounted for.

  10. The ethics of socio-ecohydrological catchment management: towards hydrosolidarity

    Directory of Open Access Journals (Sweden)

    M. Falkenmark

    2002-01-01

    Full Text Available This paper attempts to clarify key biophysical issues and the problems involved in the ethics of socio-ecohydrological catchment management. The issue in managing complex systems is to live with unavoidable change while securing the capacity of the ecohydrological system of the catchment to sustain vital ecological goods and services, aquatic as well as terrestrial, on which humanity depends ultimately. Catchment management oriented to sustainability has to be based on ethical principles: human rights, international conventions, sustaining crucial ecological goods and services, and protecting ecosystem resilience, all of which have water linkages. Many weaknesses have to be identified, assessed and mitigated to improve the tools by which the ethical issues can be addressed and solved: a heritage of constraining tunnel vision in both science and management; inadequate shortcuts made in modern scientific system analyses (e.g. science addressing sustainability issues; simplistic technical-fix approaches to water and ecosystems in land/water/ecosystem management; conventional tools for evaluation of scientific quality with its focus on “doing the thing right” rather than “doing the right thing”. The new ethics have to incorporate principles that, on a catchment basis, allow for proper attention to the hungry and poor, upstream and downstream, to descendants, and to sites and habitats that need to be protected. Keywords: catchment, hydrosolidarity, ecosystem, water determinants, resilience, green water, blue water, sustainability science

  11. Agricultural Catchments: Evaluating Policies and Monitoring Adaptive Management

    Science.gov (United States)

    Jordan, P.; Shortle, G.; Mellander, P. E.; Shore, M.; McDonald, N.; Buckley, C.

    2014-12-01

    Agricultural management in river catchments must combine the objectives of economic profit and environmental stewardship and, in many countries, mitigate the decline of water quality and/or maintain high water quality. Achieving these objectives is, amongst other activities, in the remit of 'sustainable intensification'. Of concern is the efficient use of crop nutrients, phosphorus and nitrogen, and minimising or offsetting the effects of transfers from land to water - corner-stone requirements of many agri-environmental regulations. This requires a robust monitoring programme that can audit the stages of nutrient inputs and outputs in river catchments and indicate where the likely points of successful policy interventions can be observed - or confounded. In this paper, a catchment, or watershed, experimental design and results are described for monitoring the nutrient transfer continuum in the Irish agricultural landscape against the backdrop of the European Union Nitrates and Water Framework Directives. This Agricultural Catchments Programme experimental design also serves to indicate water quality pressure-points that may be catchment specific as agricultural activities intensify to adapt to national efforts to build important parts of the post-recession economy.

  12. Topographical controls on soil moisture distribution and runoff response in a first order alpine catchment

    Science.gov (United States)

    Penna, Daniele; Gobbi, Alberto; Mantese, Nicola; Borga, Marco

    2010-05-01

    Hydrological processes driving runoff generation in mountain basins depend on a wide number of factors which are often strictly interconnected. Among them, topography is widely recognized as one of the dominant controls influencing soil moisture distribution in the root zone, depth to water table and location and extent of saturated areas possibly prone to runoff production. Morphological properties of catchments are responsible for the alternation between steep slopes and relatively flat areas which have the potentials to control the storage/release of water and hence the hydrological response of the whole watershed. This work aims to: i) identify the role of topography as the main factor controlling the spatial distribution of near-surface soil moisture; ii) evaluate the possible switch in soil moisture spatial organization between wet and relatively dry periods and the stability of patterns during triggering of surface/subsurface runoff; iii) assess the possible connection between the develop of an ephemeral river network and the groundwater variations, examining the influence of the catchment topographical properties on the hydrological response. Hydro-meteorological data were collected in a small subcatchment (Larch Creek Catchment, 0.033 km²) of Rio Vauz basin (1.9 km²), in the eastern Italian Alps. Precipitation, discharge, water table level over a net of 14 piezometric wells and volumetric soil moisture at 0-30 cm depth were monitored continuously during the late spring-early autumn months in 2007 and 2008. Soil water content at 0-6 and 0-20 cm depth was measured manually during 22 field surveys in summer 2007 over a 44-sampling point experimental plot (approximately 3000 m²). In summer 2008 the sampling grid was extended to 64 points (approximately 4500 m²) and 28 field surveys were carried out. The length of the ephemeral stream network developed during rainfall events was assessed by a net of 24 Overland Flow Detectors (OFDs), which are able to

  13. Element export from a small catchment in the tropical montane forest of Ecuador responds to climate change

    Science.gov (United States)

    Leimer, Sophia; Willimann, Elias; Alaoui, Abdallah; Trachte, Katja; Wilcke, Wolfgang

    2015-04-01

    In a very remote tropical montane rain forest in the Ecuadorian Andes on the rim of the Amazon basin, increasing temperatures, longer dry spells, and an associated reduction in soil moisture were observed in the past 15 years. In the study ecosystem, element exports from a 9-ha large catchment with stream water are linked to the depth of water flow through soil because of vertical variations in soil chemical properties. The further increase in temperature and precipitation, as predicted by climate models, will have an impact on the water flow paths in soil and therefore alter element exports. Hence, we investigated how future element exports from this catchment in Ecuador will develop under the emission scenarios A1B and B1 for the decades 2050-2059 and 2090-2099 compared to current element exports. Discharge from the study catchment was measured in 1998-2013, partly in high resolution. Element concentrations in stream water (total organic carbon, NO3-N, NH4-N, dissolved organic nitrogen, PO4-P, total dissolved phosphorus, S, Cl, K, Ca, Mg, Na, Zn, Al, Mn) were measured in 1998-2012 in weekly resolution. Based on catchment properties, measured climate, and water flow data, discharge in 1998-2013 was simulated in daily resolution with the hydrological model WaSiM. From the hydrograph of surface flow, three flow classes (baseflow, intermediate, storm) were separated and linked with stream chemical properties. Element concentrations in stream water were grouped according to the flow classes and mean concentrations per flow class were calculated. Subsequently, the mean element concentration was multiplied with the mean of the annual discharge sums per flow class resulting in current element exports. For estimations of future element exports with stream water, discharge was simulated under the emission scenarios A1B and B1 for the decades 2050-2059 and 2090-2099 and separated into the three flow classes. Future element exports per scenario were calculated according to

  14. Rainfall-runoff modelling of the Okavango River catchment to assess impacts of land use change on runoff and downstream ecosystems

    Science.gov (United States)

    Milzow, Christian; Bauer-Gottwein, Peter

    2010-05-01

    The competition between human water use and ecosystem water use is one of the major challenges for water resources management at the global scale. We analyse the situation for the Okavango River basin of southern Africa. The Okavango River is representative for many large rivers throughout the developing world in that it is ungauged and poorly studied. The Okavango basin - spanning over Angola, Namibia and Botswana - represents a multi-objective problem in an international setting. Economic benefits of agricultural development and conservation of ecosystem services call for opposed actions. A semi-distributed rainfall-runoff model of the Okavango catchment is set up using the Soil and Water Assessment Tool (SWAT). The model is sufficiently physically based to simulate the impact on runoff of extent of agricultural use, crop types and management practices. Precipitation and temperature inputs are taken from datasets covering large parts of the globe. The methodology can thus easily be applied for other ungauged catchments. For temperature we use the ERA-Interim reanalysis product of the European Centre for Medium-Range Weather Forecasts and for precipitation the Famine Early Warning Systems Network data (FEWS-Net). Tropical Rainfall Measurement Mission (TRMM) data resulted in poor model performance compared to the FEWS-Net data. Presently, the upstream catchment in Angola is largely pristine and agriculture is basically restricted to dry land subsistence farming. But economic growth in Angola is likely to result in agricultural development and consequent impacts on catchment runoff. Land use scenarios that are simulated include large scale irrigated agriculture with water extractions from the river and the shallow aquifer. Climate change impacts are also studied and compared to land use change impacts. The downstream part of the basin consists of the large Okavango Wetlands, which are a biodiversity hotspot of global importance and, through tourism, an important

  15. Explanatory characteristics for nutrient concentrations and loads in the Sava River Catchment and cross-regionally

    Science.gov (United States)

    Levi, L.; Cvetkovic, V.; Destouni, G.

    2015-12-01

    This study compiles estimates of waterborne nutrient concentrations and loads in the Sava River Catchment (SRC). Based on this compilation, we investigate hotspots of nutrient inputs and retention along the river, as well as concentration and load correlations with river discharge and various human drivers of excess nutrient inputs to the SRC. For cross-regional assessment and possible generalization, we also compare corresponding results between the SRC and the Baltic Sea Drainage Basin (BSDB). In the SRC, one small incremental subcatchment, which is located just downstream of Zagreb and has the highest population density among the SRC subcatchments, is identified as a major hotspot for net loading (input minus retention) of both total nitrogen (TN) and total phosphorus (TP) to the river and through it to downstream areas of the SRC. The other SRC subcatchments exhibit relatively similar characteristics with smaller net nutrient loading. The annual loads of both TN and TP along the Sava River exhibit dominant temporal variability with considerably higher correlation with annual river discharge (R2 = 0.51 and 0.28, respectively) than that of annual average nutrient concentrations (R2 = 0.0 versus discharge for both TN and TP). Nutrient concentrations exhibit instead dominant spatial variability with relatively high correlation with population density among the SRC subcatchments (R2=0.43-0.64). These SRC correlation characteristics compare well with corresponding ones for the BSDB, even though the two regions are quite different in their hydroclimatic, agricultural and wastewater treatment conditions. Such cross-regional consistency in dominant variability type and explanatory catchment characteristics may be a useful generalization basis, worthy of further investigation, for at least first-order estimation of nutrient concentration and load conditions in less data-rich regions.

  16. Remote sensing Penman-Monteith model to estimate catchment evapotranspiration considering the vegetation diversity

    Science.gov (United States)

    Li, Fawen; Cao, Runxiang; Zhao, Yong; Mu, Dongjing; Fu, Changfeng; Ping, Feng

    2015-09-01

    A new method for calculating evaporation is proposed, using the Penman-Monteith (P-M) model with remote sensing. This paper achieved the effective estimation to daily evapotranspiration in the Ziya river catchment by using the P-M model based on MODIS remote sensing leaf area index and respectively estimated plant transpiration and soil evaporation by using coefficient of soil evaporation. This model divided catchment into seven different sub-regions which are prairie, meadow, grass, shrub, broad-leaved forest, cultivated vegetation, and coniferous forest through thoroughly considering the vegetation diversity. Furthermore, optimizing and calibrating parameters based on each sub-region and analyzing spatio-temporal variation rules of the model main parameters which are coefficient of soil evaporation f and maximum stomatal conductance g sx . The results indicate that f and g sx calibrated by model are basically consistent with measured data and have obvious spatio-temporal distribution characteristics. The monthly average evapotranspiration value of simulation is 37.96 mm/mon which is close to the measured value with 33.66 mm/mon and the relative error of simulation results in each subregion are within 11 %, which illustrates that simulated values and measured values fit well and the precision of model is high. In addition, plant transpiration and soil evaporation account for about 84.64 and 15.36 % respectively in total evapotranspiration, which means the difference between values of them is large. What is more, this model can effectively estimate the green water resources in basin and provide effective technological support for water resources estimation.

  17. Migration of u and Th series radionuclides in soils and Sediments from a coal mining catchment

    International Nuclear Information System (INIS)

    In this work we present preliminary results about the disequilibrium of U- and Th- Decay series radionuclides in a fluvial catchment at Palencia (Spain) where several coal Mines and a coal-fired power plant are placed. The activities of several radionuclides (238U, 226Ra, 228Ra, 228Th, and 210Pb) have been determined in soil and sediments by Ray spectrometry with a n-type hp ge detector. Those measurements allow to quantify The radiological impact of the two main radionuclide sources in the catchment: - Mining drainage and migration of radionuclides from the waste piles next to the coal Mines, and; - Radon release from coal combustion at the power plant and from the ash and coal piles Stored there over long periods of time. The peculiar conditions of such environment explain the strong radionuclide Disequilibrium found in soils. Due to the high content of carbonate minerals in the Region the acid mine drainage is neutralize originating alkaline water. Both high ph Values, at least up to 8.8, and presence of carbonates in the soil solution highly increases The solubility of U. Alkaline ph favors, as well, the solubility of amphoteric Radionuclides, as radon descendants, Po, Bi and Pb, while Th and Ra associated with Carbonates behave as insoluble (Ivannovich, 1992). The above mentioned soluble elements will preferentially migrate from soil to drainage Water. The fate of the radionuclides in the river is followed by the analysis of the Sediment activities. Measurements are performed over four fractions of the sediment Sieved by grain-size, which allow to take into account the influence of the river Transport and sorting of the sediments in the radioactivity redistribution along the basin

  18. An advanced approach for catchment delineation and water balance modelling within wetlands and floodplains

    Directory of Open Access Journals (Sweden)

    S. Krause

    2005-01-01

    Full Text Available Water balance of wetlands within lowland floodplains is strongly influenced by the temporally variable spatial extent of the interactions between groundwater and surface water. A robust algorithm will be introduced which makes it possible to delineate the interaction zone between the lowland river and the floodplain. This interaction zone is specified as the "Direct Catchment" which is defined by the part of the connected floodplain in which wetland water balance is mainly affected by the surface water dynamics of the adjacent river. The delineation algorithm is based on transfer functions which were assessed by local simulation results of the integrated water balance and nutrient dynamics model IWAN. The transfer functions are further determined by mean annual groundwater depths and by simulated groundwater dynamics. They are controlled by simulation results of the maximal transversal extent of surface water influence on groundwater stages. The regionalisation of the developed delineation algorithm leads to the specification of the maximal extent of groundwater - surface water - interaction processes along the river. By application of this approach to the Havel River basin, located within lowlands of Northeaster Germany, it was possible to specify a 998.1 km2 part of the floodplain which is directly connected with the surface waters and thus called the "Direct Catchment" of the Havel river. The IWAN model was applied to simulate the water balance of the floodplain. The simulation results prove the tight interaction between river and floodplain. It is shown that the spatially and temporally variable influences of the connected floodplain on the river discharge were only important during low discharge in summer.

  19. Understanding fine sediment and phosphorous delivery in upland catchments

    Science.gov (United States)

    Perks, M. T.; Reaney, S. M.

    2013-12-01

    The uplands of UK are heavily impacted by land management including; farming and forestry operations, moorland burning, peat extraction, metal mining, artificial drainage and channelisation. It has been demonstrated that such land management activity may modify hillslope processes, resulting in enhanced runoff generation and changing the spatial distribution and magnitude of erosion. Resultantly, few upland river systems of the UK are operating in a natural state, with land management activity often resulting in increased fluxes of suspended sediment (monitored water bodies within upland areas of the UK are currently at risk of failing the Water Framework Directive (WFD) due to poor ecological status. In order to prevent the continual degradation of many upland catchments, riverine systems and their diverse ecosystems, a range of measures to control diffuse pollution will need to be implemented. Future mitigation options and measures in the UK may be tested and targeted through the EA's catchment pilot scheme; DEFRA's Demonstration Test Catchment (DTC) programmes and through the catchment restoration fund. However, restoring the physical and biological processes of past conditions in inherently sensitive upland environments is extremely challenging requiring the development of a solid evidence base to determine the effectiveness of resource allocation and to enable reliable and transparent decisions to be made about future catchment operations. Such evidence is rarely collected, with post-implementation assessments often neglected. This paper presents research conducted in the Morland sub-catchment of the River Eden within Cumbria; UK. 80% of this headwater catchment is in upland areas and is dominated by improved grassland and rough grazing. The catchment is heavily instrumented with a range of hydro-meteorological equipment. A high-tech monitoring station at the 12.5 km2 outlet provides flow, turbidity, total phosphorous (TP), total reactive phosphorous (TRP

  20. Hydrograph separation using hydrochemical tracers in the Makanya catchment, Tanzania

    Science.gov (United States)

    Mul, Marloes L.; Mutiibwa, Robert K.; Uhlenbrook, Stefan; Savenije, Hubert H. G.

    Hydrochemical tracers were used to separate and quantify different runoff components in the semi-arid Makanya catchment in the South Pare Mountains of Tanzania. One flood event was investigated during the rainy season of October-December 2005 and analysed for electrical conductivity, dissolved silica and major anions and cations. The event on 9 November 2005 showed two peaks, each originating from one of two sub-catchments, upper-Vudee and Ndolwa, each with a distinct water quality signature. Hydrograph separation indicated that the two peaks in the hydrograph originated from a delay in response between the two catchments. The hydrograph separation indicated that, for this event, over 95% of the discharge could be attributed to sub-surface runoff, while the remainder was due to faster surface runoff processes. The dominance of sub-surface processes was also indicated by the lack of suspended sediments in the samples, which is a clear indication that no surface runoff took place.

  1. Assessment of Runoff Contributing Catchment Areas in Rainfall Runoff Modelling

    DEFF Research Database (Denmark)

    Thorndahl, Søren Liedtke; Johansen, C.; Schaarup-Jensen, Kjeld

    In numerical modelling of rainfall caused runoff in urban sewer systems an essential parameter is the hydrological reduction factor which defines the percentage of the impervious area contributing to the surface flow towards the sewer. As the hydrological processes during a rainfall are difficult...... to determine with significant precision the hydrological reduction factor is implemented to account all hydrological losses except the initial loss. This paper presents an inconsistency between calculations of the hydrological reduction factor, based on measurements of rainfall and runoff, and till...... now recommended literary values for residential areas. It is proven by comparing rainfall-runoff measurements from four different residential catchments that the literary values of the hydrological reduction factor are over-estimated for this type of catchments. In addition, different catchment...

  2. Modelling a river catchment using an electrical circuit analogue

    Directory of Open Access Journals (Sweden)

    C. G. Collier

    1998-01-01

    Full Text Available An electrical circuit analogue of a river catchment is described from which is derived an hydrological model of river flow called the River Electrical Water Analogue Research and Development (REWARD model. The model is based upon an analytic solution to the equation governing the flow of electricity in an inductance-capacitance-resistance (LCR circuit. An interpretation of L, C and R in terms of catchment parameters and physical processes is proposed, and tested for the River Irwell catchment in northwest England. Hydrograph characteristics evaluated using the model are compared with observed hydrographs, confirming that the modelling approach does provide a reliable framework within which to investigate the impact of variations in model input data.

  3. Transport and deposition of carbon at catchment scale: stabilization mechanisms approach

    Science.gov (United States)

    Martínez-Mena, María; Almagro, María; Díaz-Pereira, Elvira; García-Franco, Noelia; Boix-Fayos, Carolina

    2016-04-01

    Terrestrial sedimentation buries large amounts of organic carbon (OC) annually, contributing to the terrestrial carbon sink. The temporal significance of this sink will strongly depend on the attributes of the depositional environment, but also on the characteristics of the OC reaching these sites and its stability upon deposition. The fate of the redistributed OC will ultimately depend on the mechanisms of its physical and chemical protection against decomposition, its turnover rates and the conditions under which the OC is stored in sedimentary settings. This framework is more complex in Mediterranean river