WorldWideScience

Sample records for catchment area analyses

  1. GIS-based Approaches to Catchment Area Analyses of Mass Transit

    DEFF Research Database (Denmark)

    Andersen, Jonas Lohmann Elkjær; Landex, Alex

    2009-01-01

    Catchment area analyses of stops or stations are used to investigate potential number of travelers to public transportation. These analyses are considered a strong decision tool in the planning process of mass transit especially railroads. Catchment area analyses are GIS-based buffer and overlay...

  2. Catchment areas for public transport

    DEFF Research Database (Denmark)

    Andersen, Jonas Lohmann Elkjær; Landex, Alex

    2008-01-01

    the simplest approach. The Service Area approach is based on searches in road networks and represents the actual feeder routes and is thereby a more detailed approach. The Service Area approach can be refined by adding additional resistance to certain points in the road network, e.g. stairways. Differences...... by calculating travel potential along the line. The article shows how the different approaches result in differences in the examined catchment areas. It shows how the Service Area approach prevents inaccessible areas to be included in the catchment area and how it allows for detours in feeder routes to....../from stations. The article also shows how the refinement of the Service Area approach with additional time resistance results in smaller catchment areas when the feeder routes cross stairs. It is concluded that GIS-based catchment area analyses are a multiple decision support tool for planning of public...

  3. A detailed study on Catchment delineation for Urban areas

    Science.gov (United States)

    Sharma, B.; B M, A.; Lohani, B.; Jain, A.

    2015-12-01

    Urban flood modelling is carried out for predicting, analysing and planning of floods in urban areas. Catchment information is an important input for urban flood modelling. Automatic catchment delineation at gully gratings for urban areas using appropriate software packages/methods along with an appropriate set of input data and parameters is still a research challenge. Considering the above, the aim of this study is to (i) identify the best suitable software for automatic catchment delineation by considering gully grating as outlet (ii) understand the effect of resolution of DEM on catchments delineated (iii) understand whether to consider DEM or DSM for catchment delineation (iv) study the effect of grid based and TIN based DEM. In this study catchment delineation has been investigated considering IIT Kanpur as a study site. LiDAR data are used to generate DEM/DSM of the study area. A comparative study of catchment delineation has been carried out between ArcHydro 10.1, BASINS 4.1, ArcSWAT, WMS 7.1, and HEC-GeoHMS approaches. Catchments have been delineated for different drainage threshold areas using gully grating points as outlets and their effects have been compared for the aforementioned software. In order to understand the effect of resolution of data, DEMs of 1m and 5m resolution have been generated and compared against each other. Effects of building ridge lines and their contribution to catchment delineation has been studied by generating a DSM of 1m resolution, and comparing the results with catchments delineated using 1m DEM. In order to assess the effects of the types of DEM over catchment delineation, a grid based DEM and TIN based DEM are compared against each other using WMS 7.1 software. The results for the catchment delineation using various software illustrate that ArcHydro 10.1 performs better than any other aforementioned software. Also, it is noted that varied drainage threshold area parameters, resolutions of DEM, selection of DEM

  4. Incorporating flood event analyses and catchment structures into model development

    Science.gov (United States)

    Oppel, Henning; Schumann, Andreas

    2016-04-01

    The space-time variability in catchment response results from several hydrological processes which differ in their relevance in an event-specific way. An approach to characterise this variance consists in comparisons between flood events in a catchment and between flood responses of several sub-basins in such an event. In analytical frameworks the impact of space and time variability of rainfall on runoff generation due to rainfall excess can be characterised. Moreover the effect of hillslope and channel network routing on runoff timing can be specified. Hence, a modelling approach is needed to specify the runoff generation and formation. Knowing the space-time variability of rainfall and the (spatial averaged) response of a catchment it seems worthwhile to develop new models based on event and catchment analyses. The consideration of spatial order and the distribution of catchment characteristics in their spatial variability and interaction with the space-time variability of rainfall provides additional knowledge about hydrological processes at the basin scale. For this purpose a new procedure to characterise the spatial heterogeneity of catchments characteristics in their succession along the flow distance (differentiated between river network and hillslopes) was developed. It was applied to study of flood responses at a set of nested catchments in a river basin in eastern Germany. In this study the highest observed rainfall-runoff events were analysed, beginning at the catchment outlet and moving upstream. With regard to the spatial heterogeneities of catchment characteristics, sub-basins were separated by new algorithms to attribute runoff-generation, hillslope and river network processes. With this procedure the cumulative runoff response at the outlet can be decomposed and individual runoff features can be assigned to individual aspects of the catchment. Through comparative analysis between the sub-catchments and the assigned effects on runoff dynamics new

  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...

  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. Examining the Potential Travellers in Catchment Areas for Public Transport

    DEFF Research Database (Denmark)

    Landex, Alex; Hansen, Stephen

    2006-01-01

    The paper presents a method to examine the catchment areas for stops in high quality public transport systems based on the actual 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...

  8. Assessment of Runoff Contributing Catchment Areas in Rainfall Runoff Modelling

    DEFF Research Database (Denmark)

    Thorndahl, Søren Liedtke; Johansen, C.; Schaarup-Jensen, Kjeld

    2005-01-01

    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...... 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 descriptions...

  9. 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...... 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 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 descriptions...

  10. Nutrient Transport in the Lower Seyhan Catchment Area

    OpenAIRE

    Aslan, Gamze

    1999-01-01

    The Lower Seyhan Catchment Area starts at the downstream of the Seyhan Dam on the Seyhan River. This fertile area is exposed to dense agricultural activities. Nutrient loads (nitrogen and phosphorus) from these activities create an important pollution potential for surface and groundwater resources in the area. In addition to the agricultural areas, these nutrient loads also originate from domestic and industrial discharges. In this study, the transport of the estimated nutrient lo...

  11. 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

  12. Geographically Isolated Wetlands and Catchment Hydrology: A Modified Model Analyses

    Science.gov (United States)

    Evenson, G.; Golden, H. E.; Lane, C.; D'Amico, E.

    2014-12-01

    Geographically isolated wetlands (GIWs), typically defined as depressional wetlands surrounded by uplands, support an array of hydrological and ecological processes. However, key research questions concerning the hydrological connectivity of GIWs and their impacts on downgradient surface waters remain unanswered. This is particularly important for regulation and management of these systems. For example, in the past decade United States Supreme Court decisions suggest that GIWs can be afforded protection if significant connectivity exists between these waters and traditional navigable waters. Here we developed a simulation procedure to quantify the effects of various spatial distributions of GIWs across the landscape on the downgradient hydrograph using a refined version of the Soil and Water Assessment Tool (SWAT), a catchment-scale hydrological simulation model. We modified the SWAT FORTRAN source code and employed an alternative hydrologic response unit (HRU) definition to facilitate an improved representation of GIW hydrologic processes and connectivity relationships to other surface waters, and to quantify their downgradient hydrological effects. We applied the modified SWAT model to an ~ 202 km2 catchment in the Coastal Plain of North Carolina, USA, exhibiting a substantial population of mapped GIWs. Results from our series of GIW distribution scenarios suggest that: (1) Our representation of GIWs within SWAT conforms to field-based characterizations of regional GIWs in most respects; (2) GIWs exhibit substantial seasonally-dependent effects upon downgradient base flow; (3) GIWs mitigate peak flows, particularly following high rainfall events; and (4) The presence of GIWs on the landscape impacts the catchment water balance (e.g., by increasing groundwater outflows). Our outcomes support the hypothesis that GIWs have an important catchment-scale effect on downgradient streamflow.

  13. North Putrajaya Catchment Area Putrajaya, Malaysia-Challenges in Water Quality Management

    International Nuclear Information System (INIS)

    The Putrajaya Administrative area covers 70 % of the Putrajaya Lake catchment area. Development work carried out within the Putrajaya area abides by the rules and regulations set by the Putrajaya Corporation to ensure that the quality of the lake water and wetland within the Putrajaya area meets the stipulated benchmark standards. However, 30 % of the Putrajaya lake and wetland catchment area is located outside of administration and prerogative of the Putrajaya Corporation. The North Putrajaya catchment area which originates from the Sg. Chuau River contributes the bulk of the water that flows into the lake and wetlands of Putrajaya. Water quality data collected by the Putrajaya Corporation for the period of 2002 to 2005 has been analysed to identify major issues in the Putrajaya Wetland North Catchment area. Data from 2002 shows average percentage parameter of non-compliance Putrajaya Standard for ammoniacal nitrogen (NH3-N) at 43.7 %, E. coli at 31.3 % and TSS at 12.5 % while the DO and COD are both 6.2 %. For 2003, the average percentage parameter of non compliance for NH3-N was at 23.7 %, E. coli at 18.4 %, total coliform at 18.4 %, TSS at 2.6 %, DO at 13.2 %, COD at 13.2 % and BOD at 10.5 %. For 2004, the average percentage parameter of non complying for NH3-N was at 35.5 %, E. coli at 22.6 %, total coliform at 12.9 %, TSS at 9.7 %, COD at 3.2 % and BOD at 16.1 %. For 2005, the average percentage parameter of non compliance were at is 36.4 % for E. coli, 22.7 % for NH3-N, 18.2 % for total coliform, 13.6 % for BOD and 4.5 % for both DO and COD. In conclusion the analysed data within the four year period showed that the NH3-N and E. coli discharge from the north catchment area did not comply with the Putrajaya Standard. The main factors of water quality issues in the Putrajaya Wetland North Catchment area include the failure of integrating the management of the catchment areas and the stake holders attitude of total disregard of the management and control of

  14. FISHERY MANAGEMENT IN THE DANUBE CATCHMENT AREA

    Directory of Open Access Journals (Sweden)

    Tomislav Treer

    1999-12-01

    Full Text Available There are three successive regions of the Danube, each of which has to deal with its own problems in fisheries. Sport fishing and ecological recontruction problem matters predominate in the upper flow. These problems also characterize the middle flow, where to a certain extent, commercial fishery is coming into view, while the lower flow has to deal with commercial fishery problems to full extent. The difference is not so much due to the morphometry as to the development and state of the economy of the countries in the river basin, their legislation on fishery and the manner in which the legislation is applied. Numerous dams of the upper flow of the Danube (29 in Germany, 9 in Austria, influence significantly the ichthyocenoses. An extreme example of that is Gabčikovo dam at the Slovak-Hungarian border where fish catch decreased to one fourth. In the lower segment of the Danube fish catch falls down to one third and is followed, by a drastically negative change of fish species composition. The records show that highly valued species as sturgeons, pike and tench are in drastic decline over the last few years. The changes were caused by physical barriers, like dams and weirs, by water pollution, by increasing concentration of nutrients and heavy metals, by poaching and by overexploitation. For all those alarming reasons, some legal interventions in commercial fishery must be undertaken. In the middle flow, where the Danube flows through Croatian territory, there have also been declining trends of bentivore and phytophyl species respectively. The law supports the coexistence of sport and commercial fishery in this area and although sport fishing should be given the advantage, commercial fishing should be rigorously supervised and allowed only when there is a naturally produced surplus. Because of fish migrations and political frontiers of Danube area, it is essential that the neighboring countries coordinate their efforts in managing fisheries

  15. Hydrological Dynamics In High Mountain Catchment Areas of Central Norway

    Science.gov (United States)

    Löffler, Jörg; Rößler, Ole

    Large-scaled landscape structure is regarded as a mosaic of ecotopes where process dynamics of water and energy fluxes are analysed due to its effects on ecosystem functioning. The investigations have been carried out in the continental most Vågå/Oppland high mountains in central Norway since 1994 (LÖFFLER &WUNDRAM 1999, 2000, 2001). Additionally, comparable investigations started in 2000 dealing with the oceanic high mountain landscapes on same latitudes (LÖFFLER et al. 2001). The theoretical and methodological framework of the project is given by the Landscape-Ecological Complex Analysis (MOSIMANN 1984, 1985) and its variations due to technical and principle methodical challenges in this high mountain landscape (KÖHLER et al. 1994, LÖFFLER 1998). The aim of the project is to characterize high mountain ecosystem structure, functioning and dynamics within small catchment areas, that are chosen in two different altitudinal belts each in the eastern continental and the western oceanic region of central Norway. In the frame of this research project hydrological and meteorological measurements on ground water, percolation and soil moisture dynamics as well as on evaporation, air humidity and air-, surface- and soil-temperatures have been conducted. On the basis of large-scaled landscape-ecological mappings (LÖFFLER 1997) one basic meteorological station and several major data logger run stations have been installed in representative sites of each two catchment areas in the low and mid alpine belts of the investigation regions ( JUNGet al. 1997, LÖFFLER &WUNDRAM 1997). Moreover, spatial differentiations of groundwater level, soil moisture and temperature profiles have been investigated by means of hand held measurements at different times of the day, during different climatic situations and different seasons. Daily and annual air-, surface- and soil-temperature dynamics are demonstrated by means of thermoisopleth-diagrams for different types of ecotopes of the

  16. Agroecology and biodiversity of the catchment area of Swat River

    International Nuclear Information System (INIS)

    Agroecological studies of the of the Swat River catchment area showed that the terrestrial ecosystem of the area is divided into subtropical, humid temperate, cool temperate, cold temperate, subalpine, alpine and cold desert zones. Indicator species along with their altitudinal limits are specified for each zone. Unplanned population growth, agriculture extension, habitat losses, deforestation, environmental pollution and unwise use of natural resources are threats to the natural biodiversity of these zones. Its severity is very evident in the subtropical and humid temperate zones. The losses encountered to the biodiversity of the area under the influence of various anthropogenic stresses are highlighted. (author)

  17. The scaling method of specific catchment area from DEMs

    Institute of Scientific and Technical Information of China (English)

    YANG Xin; TANG Guoan; XlAO Chenchao; GAO Yiping; ZHU Shijie

    2011-01-01

    Specific Catchment Area (SCA) is defined as the upstream catchment area of a unit contour.As one of the key terrain parameters,it is widely used in the modeling of hydrology,soil erosion and ecological environment.However,SCA value changes significantly at different DEM resolutions,which inevitably affect terrain analysis results.SCA can be described as the ratio of Catchment Area (CA) and DEM grid length.In this paper,the scale effect of CA is firstly investigated.With Jiuyuangou Gully,a watershed about 70 km2 in northern Shaanxi Province of China,as the test area,it is found that the impacts of DEM scale on CA are different in spatial distribution.CA value in upslope location becomes bigger with the decrease of the DEM resolution.When the location is close to downstream areas the impact of DEM scale on CA is gradually weakening.The scale effect of CA can be concluded as a mathematic trend of exponential decline.Then,a downscaling model of SCA is put forward by introducing the scale factor and the location factor.The scaling model can realize the conversion of SCA value from a coarse DEM resolution to a finer one at pixel level.Experiment results show that the downscaled SCA was well revised,and consistent with SCA at the target resolution with respect to the statistical indexes,histogram and spatial distribution.With the advantages of no empirical parameters,the scaling model could be considered as a simple and objective model for SCA scaling in a rugged drainage area.

  18. Characteristics of Areas Vulnerable to Climate Change in the Romanian Tisa Catchment Area

    Directory of Open Access Journals (Sweden)

    ALINA CHICOŞ

    2010-01-01

    Full Text Available The article summarizes the analysis carried out in two European projects in progress on the Romanian territory of the Tisa Catchment Area and aims to identify areas vulnerable to climate change, and their socio-demographic characterization. In areas identified, the most exposed category of the population is elderly and the most affected economic activity is agriculture.

  19. Characteristics of Areas Vulnerable to Climate Change in the Romanian Tisa Catchment Area

    OpenAIRE

    ALINA CHICOŞ; GEORGIANA TOTH; ALEXANDRU IONUŢ PETRIŞOR

    2010-01-01

    The article summarizes the analysis carried out in two European projects in progress on the Romanian territory of the Tisa Catchment Area and aims to identify areas vulnerable to climate change, and their socio-demographic characterization. In areas identified, the most exposed category of the population is elderly and the most affected economic activity is agriculture.

  20. ECOLOGICAL ASPECTS OF BENTHIC COMMUNITIES FROM SOMESUL CALD CATCHMENT AREA

    Directory of Open Access Journals (Sweden)

    Karina Battes

    2001-01-01

    Full Text Available The present paper represents a preliminary study of periphyton and zoobenthos community from the Someşul Cald catchment area. Zoobenthos was sampled seasonally during 2000. Benthic community structure was similar at the five sampling sites. Thus, mayflies and chironomids recorded high numerical percentage abundances and densities. Oligochaetes, water mites and caddisflies were identified to species level. 38 Oligochaeta, 28 water mite and 12 caddis fly species were found in the sampling period. The samplings collected in the year 2001 included 80 algal species belonging to 5 phyla. Diatoms (Bacillariophyta dominated both qualitatively and quantitatively at all sampling sites.

  1. Uniform Transnational Assessment of the Environmental Indices from the Romanian Catchment Area of the Tisa River

    Directory of Open Access Journals (Sweden)

    SILVIU-FLORIN FONOGEA

    2010-01-01

    Full Text Available The uniform transnational assessment of the environmental indices in the catchment area of the Tisa river aims at rehabilitating, protecting and conserving the environmental systems, as well as creating a commonly strategic demarche concerning a sustainable spatial development, based on integrated intersectorial approaches of environmental issues, viewed in their territorial dimension. The information necessary in underlining the current situation in the Romanian catchment area of the Tisa has been structured according to the following categories of analysed indices: sources of surface waters, resources of drinkable water and water supply resources, the risk of not reaching the environmental objectives, significant sources of water pollution (punctual sources of pollution, diffuse sources of pollution, significant hydromorphic pressure, the quality of water, significant sources of air pollution, soils affected by agricultural and industrial activities, nature protection and waste management.

  2. Determination of catchment area of surface water in gis for suitable land management

    OpenAIRE

    Kovačič, Primož

    2009-01-01

    The main purpose of this diploma thesis is defining the catchment areas of surface waters for suitable land management, which is also reflected on water quality. Besides basic concepts, legal backgrounds in Slovenia, which are related to water areas and water management, are introduced. The thesis presents the existing models of catchment areas of waters in Slovenia and it especially exposes the subsistent methodology of defining catchment areas of surface waters on the basis of digital eleva...

  3. Correcting for catchment area nonresidency in studies based on tumor-registry data

    International Nuclear Information System (INIS)

    We discuss the effect of catchment area nonresidency on estimates of cancer incidence from a tumor-registry-based cohort study and demonstrate that a relatively simple correction is possible in the context of Poisson regression analysis if individual residency histories or the probabilities of residency are known. A comparison of a complete data maximum likelihood analysis with several Poisson regression analyses demonstrates the adequacy of the simple correction in a large simulated data set. We compare analyses of stomach-cancer incidence from the Radiation Effects Research Foundation tumor registry with and without the correction. We also discuss some implications of including cases identified only on the basis of death certificates. (author)

  4. Sustainable rainwater management in the Emscher river catchment area.

    Science.gov (United States)

    Becker, M; Raasch, U

    2002-01-01

    The wastewater management system of the Emscher region is currently being radically restructured. The receiving waters currently surviving as open sewers are to be freed of their wastewater burden and reconstituted to a state as natural as possible, while the wastewater is to be routed underground to the treatment plants. Great importance is attached to the most natural possible rainwater management, in order to buffer extreme run-off situations in the watercourses and to minimize the costs for residential-area water management engineering. Rethinking, which in many cases percolates through only slowly, is necessary in many respects for this purpose. A contest has been set up in the Emscher catchment area in order to accelerate this in the existing residential areas. Seepage, decentralized retention, disconnection and discharge into bodies of water and watercourses have been financially supported. The results are presented and the further procedure deriving from them discussed.

  5. IMAGERY: A CASE STUDY IN KAYANGAN CATCHMENT AREA, YOGYAKARTA, INDONESIA

    Directory of Open Access Journals (Sweden)

    Ratih Fitria Putri

    2013-01-01

    Full Text Available The differential synthetic aperture radar in terferometry (DInSAR technique is applied to the ALOS PALSAR data to observe su rface displacement in Kayangan catchment area, Yogyakarta, Indonesia. Change detecti on is implemented to extract information on several landslides that occurred in the region in a time span between 2007 and 2009. The advanced DInSAR processing of im ages (2007–2009 has shown slight surface movements before the landslide events. These results are compared and validated with available GPS measurements. Our analysis reveals that Kayangan catchment area exhibits clear indication of surface displacements varying from 5.2 to 57.9 cm/year. The occurence of landslides has been analy zed in relation to the following terrain parameters; elevation, slope, distance to stream network, geology, landuse, and distance from road. Among these factors, it is found that 18% of landslides occur in elevation >100 m, 56% in slope 30–40°, 34% in <25 m distance to stream networks, 100% in kebobutak formation, 67% in mix garden of land use types, and 100% in <25 m distance from road. The landuse is the most in fluential factor, since there are only four types of landuse that can lead to lands lide occurrence, i.e., mixed garden, dryland agriculture, bush, and settlement. The analys is of land deformation is promising for assessing acceleration caused by a destabilizing anthropogenic change, and relationship between seasonal precipitation a nd deformation variability.

  6. Optimal catchment area and primary PCI centre volume revisited

    DEFF Research Database (Denmark)

    Schoos, Mikkel Malby; Pedersen, Frants; Holmvang, Lene;

    2015-01-01

    baseline, organisational and procedural characteristics. Quality measures were treatment delays and 30-day all-cause mortality. In the three-year study period, 2,066 consecutive pPCIs were performed. After the fusion of the two centres, pPCI procedures increased by 102%, while door-to-balloon remained......AIMS: The currently stated optimal catchment population for a pPCI centre is 300,000-1,100,000, resulting in 200-800 procedures/year. pPCI centres are increasing in number even within small geographic areas. We describe the organisation and quality of care after merging two high-volume centres......, creating one mega centre serving 2.5 million inhabitants, and performing ~1,000 procedures/year. METHODS AND RESULTS: In this descriptive cohort study, we linked individual-level data from the national Central Population Register holding survival status with our in-hospital dedicated PCI database of...

  7. Elaboration of a complex GIS application in a catchment area.

    Science.gov (United States)

    Németh, T; Szabó, J; Pásztor, L; Bakacsi, Zs

    2002-01-01

    Rearrangement of land resources after political changes has not yet been finished in Hungary. It is almost impossible to collect information necessary for planning activities on outer areas of settlements. The data are distributed among various organizations and can be found in diverse forms or there are no available data at all. However water quality protection has become legally ordered concerning municipal activities around Lake Balaton which is considered as the most important recreation area and tourist target in Hungary and is also affected by a number of factors providing sources of environmental conflicts. Settlements in a catchment area (Tetves Creek) on the southern shoreline of Lake Balaton in Central Hungary tendered a complex project for collecting sources of authentic data of the Hungarian rural areas along with systematizing and saving these data in a uniform GIS. An application using Autodesk MapGuide Program for Internet realization was developed. The implemented web-based system can be used in Internet and Intranet environments. PMID:12079095

  8. Evaluation of catchment contributing areas and storm runoff in flat terrain subject to urbanisation

    OpenAIRE

    O. V. Barron; D. Pollock; Dawes, W.

    2011-01-01

    Contributing Catchment Area Analysis (CCAA) is a spatial analysis technique developed and used for estimation of the hydrological connectivity of relatively flat catchments. It allows accounting for the effect of relief depressions on the catchment rainfall-runoff relationship which is not commonly considered in hydrological modelling. Analysis of distributed runoff was based on USDA runoff curves numbers (USDA, 1986), which utilised the spatial information on land cover and soil types, while...

  9. Predicting forested catchment evapotranspiration and streamflow from stand sapwood area and Aridity Index

    Science.gov (United States)

    Lane, Patrick

    2016-04-01

    Estimating the water balance of ungauged catchments has been the subject of decades of research. An extension of the fundamental problem of estimating the hydrology is then understanding how do changes in catchment attributes affect the water balance component? This is a particular issue in forest hydrology where vegetation exerts such a strong influence on evapotranspiration (ET), and consequent streamflow (Q). Given the primacy of trees in the water balance, and the potential for change to species and density through logging, fire, pests and diseases and drought, methods that directly relate ET/Q to vegetation structure, species, and stand density are very powerful. Plot studies on tree water use routinely use sapwood area (SA) to calculate transpiration and upscale to the stand/catchment scale. Recent work in south eastern Australian forests have found stand-wide SA to be linearly correlated (R2 = 0.89) with long term mean annual loss (P-Q), and hence, long term mean annual catchment streamflow. Robust relationships can be built between basal area (BA), tree density and stand SA. BA and density are common forest inventory measurements. Until now, no research has related the fundamental stand attribute of SA to streamflow. The data sets include catchments that have been thinned and with varying age classes. Thus far these analyses have been for energy limited systems in wetter forest types. SA has proven to be a more robust biometric than leaf area index which varies seasonally. That long term ET/Q is correlated with vegetation conforms to the Budyko framework. Use of a downscaled (20 m) Aridity Index (AI) has shown distinct correlations with stand SA, and therefore T. Structural patterns at a the hillslope scale not only correlate with SA and T, but also with interception (I) and forest floor evaporation (Es). These correlations between AI and I and Es have given R2 > 0.8. The result of these studies suggest an ability to estimate mean annual ET fluxes at sub

  10. Regional estimation of torrent hazards by analysing weather radar data and catchment characteristics

    Science.gov (United States)

    Pistotnik, G.; Klebinder, K.; Chifflard, P.; Kirnbauer, R.; Haiden, T.

    2009-04-01

    Torrent hazards in mountain areas in the eastern part of Lower Austria are mostly triggered by convective rainfall events during thunderstorms. The Austrian Avalanche and Torrent Control Service commissioned a project for a regional analysis of torrent hazard potential in the region Bucklige Welt / Wechselland as the basis for detailed investigations and torrent control measures which will be planned later, taking into account the hazard potential of individual streams, the most dangerous first, the less dangerous later. Thus, the following problems had to be analysed: Are there any typical points of origin of convective storms in or near the project region? Are there any typical tracks of these storms endangering the region, and what is their extent and lifetime? Which catchments generate more and which less runoff caused by the same precipitation amount? For approaching the meteorological part of the integrated problem the precipitation is estimated from radar data on a 15 minutes basis with a spatial resolution of 1 km, because no sufficient precipitation measurements are available. Within the nowcasting system INCA (Integrated Nowcasting through Comprehensive Analysis) of the Central Institute for Meteorology and Geodynamics (ZAMG) these radar data are combined with satellite data, ground data, model data from the meteorological local area model "ALADIN Vienna" and with a digital terrain model of 1 km grid space. Thus, a continuous set of precipitation fields were calculated for the years 2003 to 2007 with a temporal resolution of 15 minutes and a local resolution of 1 km. Based on this data set convective cells were identified and their tracks analysed. If a precipitation intensity of 3,8 mm/15 min was exceeded, in accordance with experiences of the meteorological remote sensing group of the ZAMG, it was a-priori assumed that this was a convective storm. According to this threshold nearly 350 convective events were automatically extracted. After discarding

  11. New Information on the Malacofauna of the Catchment Area of Rusenski Lom River (North Bulgaria

    Directory of Open Access Journals (Sweden)

    Iltcho Kolev

    2015-12-01

    Full Text Available After this short note adding 8 species to the faunal list of the area, a total of 130 mollusk species are known from the catchment area of Rusenski Lom River both aquatic and terrestrial.

  12. Utilizing Geographic Information System for Prediction of Soil Erosion in Sono Sragen Catchment Area

    OpenAIRE

    Muhammad Mukhlisin; Sukoco

    2011-01-01

    Problem statement: Embung is a small dam created by manmade lakes and used to catch water during rainy season for an irrigation source. In Sragen area, Embung Sono is one of around twenty embung that used to catch rain water for irrigation. Soil erosions in catchment area are potential to reduce water capacity of the embung. Although many embung have been constructed in Sragen areas, the numbers of soil erosion in catchment area of embung are not well considered. Approach:...

  13. 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

  14. Effects of Channelisation, Riparian Structure and Catchment Area on Physical Habitats in Small Lowland Streams

    DEFF Research Database (Denmark)

    Pedersen, Morten Lauge

    2009-01-01

    that are dominated by a hierarchy of physical processes. The complexity is further enhanced by local human alteration of the physical structure, natural processes and alteration of the riparian areas. The aim of the study was to analyse variations in land use and riparian characteristics along small Danish streams......Rivers and streams form a longitudinal network in which physical conditions and biological processes change through the river system. Geomorphology, topography, geology and hydraulic conditions change from site to site within the river system, thereby creating a complex network of reaches...... and to determine the effect of channelisation on physical habitats. Physical stream characteristics were measured in 149 stream small and medium sized Danish streams (catchment area: 0.1 to 67.2 km2). The measured physical parameters included discharge, stream slope, width, depth, current velocity, substrata...

  15. Physicochemical Quality of Irrigation Water in River Katsina-Ala Catchment Areas of Northern Nigeria

    Directory of Open Access Journals (Sweden)

    Ajon, A. T

    2014-08-01

    Full Text Available The assessment of water qualities for irrigation in river Katsina-Ala catchment areas of Benue State was carried out. Surface water and groundwater samples from three selected catchment areas namely, Logo, Ambighir and Katsina-Ala, were collected and analyzed for physicochemical parameters. Several soil samples were also analysed for infiltration capacity. All the physicochemical parameters monitored fell within FAO specifications for irrigation purposes. Groundwater samples were found to have higher concentrations of physicochemical parameters than surface water. On the basis of hydrochemical classification, earth alkali types were dominant (100% in both groundwater and surface water samples while the alkali type was totally absent. Assessment of the water samples for irrigation showed that the water samples posed no problems with regard to sodicity, salinity and lime deposition. However, high risk of infiltration was envisaged as a result of very low values of conductivity (0.03ds/m – 0.13ds/m. At the present, infiltration problem is minimal because of high proportion of sand (68% - 89% in the soils but this situation may not be sustained for long. A regression model (R = 0.773 was obtained which showed that the rate of infiltration strongly depended on the sand content of soil. Both water and soil samples were found to be suitable for a wide range of irrigation.

  16. Simulating nitrogen budgets in complex farming systems using INCA: calibration and scenario analyses for the Kervidy catchment (W. France)

    OpenAIRE

    Durand, P.

    2002-01-01

    International audience The integrated nitrogen model INCA (Integrated Nitrogen in Catchments) was used to analyse the nitrogen dynamics in a small rural catchment in Western France. The agrosystem studied is very complex, with: extensive use of different organic fertilisers, a variety of crop rotations, a structural excess of nitrogen (i.e. more animal N produced by the intensive farming than the N requirements of the crops and pastures), and nitrate retention in both hydrological stores a...

  17. Understanding Polycyclic Aromatic Hydrocarbon transfers at the catchment scale combining chemical and fallout radionuclide analyses

    Science.gov (United States)

    Gateuille, D.; Evrard, O.; Lefevre, I.; Moreau-Guigon, E.; Alliot, F.; Chevreuil, M.; Mouchel, J.-M.

    2012-04-01

    Reducing environmental contamination constitutes a major challenge for industrialized countries. Furthermore, in the European Union, Water Framework Directive (WFD; Directive 2000/60/EC) requires that the member state water bodies reach good ecological and chemical status by 2015. Polycyclic Aromatic Hydrocarbons (PAHs) are a group of persistent organic pollutants considered as priority pollutants because of their mutagenic and carcinogenic properties. They are mostly emitted by human activities such as household heating or road traffic. Although emissions have decreased during the last decades, a large amount of PAHs have been released into the atmosphere for the last two centuries. In recent years, studies dealing with PAHs have grown in number but most of them were restricted to the measurement of PAHs concentrations in the different compartments of the environment (air, soil, sediment, water, etc.). In this context, there remains a lack of knowledge about the transfers and, consequently, about the persistence of these compounds in the environment. This question is particularly acute in the Seine River basin where very high concentrations in PAHs are reported in sediment, thereby compromising the achievement of the good chemical status required by WFD. Our study aims to quantify PAHs transfers at the catchment scale by combining chemical analysis with gamma spectrometry. Atmospheric fallout, soil, river water and sediment samples were collected in two upstream sub-catchments of the Seine River basin during one year. Chemical analyses, restricted to 15 of the 16 PAHs selected by the US Environmental Protection Agency (USEPA), were carried out to determine PAHs concentrations in all samples. Contamination spectra were used to outline the potential origin of pollution. 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. material that

  18. Utilizing Geographic Information System for Prediction of Soil Erosion in Sono Sragen Catchment Area

    Directory of Open Access Journals (Sweden)

    Muhammad Mukhlisin

    2011-01-01

    Full Text Available Problem statement: Embung is a small dam created by manmade lakes and used to catch water during rainy season for an irrigation source. In Sragen area, Embung Sono is one of around twenty embung that used to catch rain water for irrigation. Soil erosions in catchment area are potential to reduce water capacity of the embung. Although many embung have been constructed in Sragen areas, the numbers of soil erosion in catchment area of embung are not well considered. Approach: Soil erosion in the Sono catchment area was analyzed using Geographic Information System (GIS and Universal Soil Loss Equation (USLE method. Results: The result showed that total number of soil erosion in the Sono catchment area is 63.50 ton/ha-year and categorized in moderate classified. Value of Sediment Delivery Ratio (SDR for catchment was 0.34. Empirical equation proposed by Renfro, Vanoni and USDA were also used to analyze the SDR value. Conclusion: It was found that USDA is the best method that can be used to predict soil erosion in Sragen area. It means the crop management and environmental conservation in Sono catchment need to be improved.

  19. Uniform Transnational Assessment of the Environmental Indices from the Romanian Catchment Area of the Tisa River

    OpenAIRE

    SILVIU-FLORIN FONOGEA; VIOREL GLIGOR; IULIU VESCAN

    2010-01-01

    The uniform transnational assessment of the environmental indices in the catchment area of the Tisa river aims at rehabilitating, protecting and conserving the environmental systems, as well as creating a commonly strategic demarche concerning a sustainable spatial development, based on integrated intersectorial approaches of environmental issues, viewed in their territorial dimension. The information necessary in underlining the current situation in the Romanian catchment area of the Tisa ha...

  20. First Flush Effects in an Urban Catchment Area in Aalborg

    DEFF Research Database (Denmark)

    Larsen, Torben; Brpch, Kirsten; Andersen, Margit Riis

    1997-01-01

    The paper describes the results of measurements from a 2 year period on a 95 hectare urban catchment in Aalborg, Denmark. The results of the rain/discharge measurements include 160 storm events corresponding to an accumulated rain depth of totally 753 mm. The water quality measurements include 15...

  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. Climate change and its impact on the Crn Drim Catchment Area In Macedonia

    International Nuclear Information System (INIS)

    In this paper it will be presented the overview of the climate change and climate regimes of the world in general according different scenarios in the latest assessment (the 3d Report published in 2001) of the Intergovernmental Panel on Climate Change (IPCC) and its impact on the Crn Drim catchment area in Macedonia.This analysis and interpretation only provides a preliminary investigation into climate change and how it will affect Ohrid and Prespa lake system as a part of Crn Drim catchment area, which is already attacked by the climate changed. From the climatological aspect two elements: temperature and rainfall, will be' calculated and their expected changes over the century in the same area. Dates used in these analyses are from the Hydro meteorological Service of Republic of Macedonia archives In the graphs are shown changes in average seasonal climate for the period around the 2080s, relative to 1961-1990 climate. Results are shown for the SRES A2 scenario, which assumes a future world of fairly conventional energy development, i.e., continuing dependence on fossil carbon fuels. The projections for average seasonal climate for temperature and precipitation are estimated and shown separately for two seasons: winter and summer. The estimated values are compared with annual mean global worming for the 2080s,-and for the SRES A2 scenario, as calculated by the IPCC (a value of about 3.2oC). The results show rate of worming greater in summer than in winter for Ohrid Lake as well as for Prespa Lake. Concerning the precipitation, it increases slightly in winter and decreases substantially in summer, by around 30 per cent. As the conclusion it is obviously that the temperature will rise in all Crn Drim catchment area with implications for increasing water temperature and water quality, which would be degraded by higher water temperature. This will increase evaporation and as the results can be expected water level decreasing. Also, higher temperatures and heat waves

  3. 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

  4. 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

  5. Water quality assessment of the Asata River catchment area in Enugu Metropolis, Southeast Nigeria

    Science.gov (United States)

    Osinowo, Olawale Olakunle

    2016-09-01

    Hydrogeochemical mapping of the Asata River Catchment area in the Enugu metropolis, southeast Nigeria was carried out in order to assess the quality of the surface and groundwater and based on the analyses of the hydrogeochemical data, establish the level of chemical contaminations which inhibit the availability of potable water in the area. Forty (40) water samples comprising five (5) springs, nineteen (19) surface (streams/rivers) and sixteen (16) groundwater (well/borehole) samples were collected and analysed for the presence and degree of contamination of nine (9) major chemical contaminants. Hydrochemical analyses indicate that Electrical Conductivity (EC) which has a linear relationship with Total Dissolved Solid (TDS) ranges between 015 and 887 μS/cm, pH between 4.4 and 8.3, nitrate (NO3-) ranges between 40 and 130 mg/l and chloride (Cl-) between 7 and 130 mg/l. The concentrations of the dissolved chemical constituents defined the pollution trend and the rate of dispersion of contaminants. The degree of contaminants followed a simple trend, where the level of contamination of the dissolved chemical constituents is least in sampled spring water, with measured chemical constituents of EC, pH, NO3- and Cl- range from 15 to 354 μS/cm; 6.4-6.5; 4.0-70 mg/l and 8-36 mg/l, respectively. However, the value of the measured chemical constituent of EC, pH, NO3- and Cl- gradually increases down the stream in both the surface (63-354 μS/cm; 4.5-7.7; 7.1-110 mg/l; 8-41 mg/l) and groundwater (56-531 μS/cm; 4.5-7.5; 40-130 mg/l; 7-130 mg/l), respectively. Noticeable peaks in contamination levels characterised sections of the study area where human population or their activities is highest. The result of the hydrogeochemical mapping indicate that Enugu coal mine operation, the industrial activities, fertilizer applied to plants cultivated on river banks and domestic human wastes which are indiscriminately dumped along river channels are the major sources of chemical

  6. Spatially distributed rockfall activity inferred from talus deposits and corresponding rockwall areas in the Gradenbach catchment (Schober Mountains, Austria)

    Science.gov (United States)

    Götz, Joachim; Buckel, Johannes; Heckmann, Tobias

    2013-04-01

    The analysis of alpine sediment cascades requires the identification, differentiation and quantification of sediment sources, storages, and transport processes. This study deals with the origin of alpine sediment transfer and relates primary talus deposits to corresponding rockwall source areas within the Gradenbach catchment (Schober Mountains, Austrian Alps). Sediment storage landforms are based on a detailed geomorphological map of the catchment which was generated to analyse the sediment transfer system. Mapping was mainly performed in the field and supplemented by post-mapping analysis using LIDAR data and digital orthophotos. A fundamental part of the mapping procedure was to capture additional landform-based information with respect to morphometry, activity and connectivity. The applied procedure provides a detailed inventory of sediment storage landforms including additional information on surface characteristics, dominant and secondary erosion and deposition processes, process activity and sediment storage coupling. We develop the working hypothesis that the present-day surface area ratio between rockfall talus (area as a proxy for volume, backed by geophysical analysis of selected talus cones) and corresponding rockwall source area is a measure of rockfall activity since deglaciation; large talus cones derived from small rockwall catchments indicate high activity, while low activity can be inferred where rockfall from large rock faces has created only small deposits. The surface area ratio of talus and corresponding rockwalls is analysed using a landform-based and a process-based approach. For the landform-based approach, we designed a GIS procedure which derives the (hydrological) catchment area of the contact lines of talus and rockwall landforms in the geomorphological map. The process-based approach simulates rockfall trajectories from steep (>45°) portions of a DEM generated by a random-walk rockfall model. By back-tracing those trajectories that

  7. Modeling pluvial flooding damage in urban environments: spatial relationships between citizens' complaints and overland catchment areas

    Science.gov (United States)

    Gaitan, Santiago; ten Veldhuis, Marie-Claire; van de Giesen, Nick

    2013-04-01

    Extreme weather events such as floods and storms are expected to cause severe economic losses in The Netherlands. Cumulative damage due to pluvial flooding can be considerable, especially in lowland areas where this type of floods occurs relatively frequently. Currently, in The Netherlands, water-related damages to property and contents are covered through private insurance. As pluvial flooding is becoming heavier and more likely to occur, sound modelling of damages is required to ensure that insurance systems are able to stand as an adaptation measure. Current damage models based on rainfall intensity, registries of insurance claims, and classifications of building types are unable to fully explain damage variability. Further developments assessing additional explanatory factors and reducing uncertainties, are required in order to significantly explain damage. In this study, urban topography is used as an explanatory factor for modelling of urban pluvial flooding. Flood damage is evaluated based on complaints data, a valuable resource for assessing vulnerability to urban pluvial flooding. Though previous research has shown coincidences between the localization of high complaint counts and large size catchments areas in Rotterdam, additional research is needed to establish the precise spatial relationship of those two variables. This additional task is the focus of the presented work. To that end a data base of complaints, that was made available by the Municipality Administration of the City, will be analysed. It comprises close to 36800 complaints from 2004 to 2011. The geographical position of the registries is aggregated into 4 to 6-digit Postal Code zones, which represents entire streets or relative positions along a street, respectively. The Municipality also provided the DEM, characterized by a spatial resolution of 0.5 m × 0.5 m, a vertical precision of 5 cm, and an accuracy better than two standard deviations of 15 cm. First the localization of complaints

  8. IMPACT OF URBANIZATION OF SUBURBAN AREA ON WATER RELATION IN THE SMALL CATCHMENTS

    Directory of Open Access Journals (Sweden)

    Jolanta Kanclerz

    2016-02-01

    Full Text Available This paper presents results of analysis focused on impact of urbanization of Poznań suburban area on water relation for Doływ spod Lusówka and Przeźmierki catchments during 1936–2011. Both catchments are located in municipalities which recently showing sharp growth in urban area. Analysis of changes in land use for studied catchments showed almost 5-fold increase in urban area for Dopływ spod Lusówka and 10-fold for Przeźmierka. As a consequence of land sealing increase in amounts of effective precipitation was observed that led to fast runoff of rain waters and almost double flow in watercourses.

  9. Catchments network on badlands around Mediterranean area (RESOBAM)

    Science.gov (United States)

    Copard, Yoann; Lebouteiller, Caroline; Regues-Munoz, David; Latron, Jerome; Solé-Benet, Albert; Canton, Yolanda; Nadal-Romero, Estela; Della Seta, Marta; Rossi, Mauro; Capolongo, Domenico; Maquaire, Olivier; Forey, Estelle; Di-Giovanni, Christian; Gallart, Francesc; Delmonte, Maurizio; Vergari, Francesca; Massei, Nicolas; Torri, Dino

    2016-04-01

    Between 2013 and 2014, a network funded by MISTRALS-ENVIMED institution, was born around some instrumented catchments developing a badland-type morphology. This network has grouped 3 countries (France, Spain and Italy) with 12 scientific labs. RESOBAM has concerned two sites in France (Draix-Bléone and Vaches Noires), three in Spain (Vallcebre, Araguas and El Cautivo) and some sites in Italy (Tuscany, Basilicata). Main goal of this network was to federate the research around badlands at the European scale, by proposing some scientific topics as: sediment and water transports / budget, (bio)geochemical cycles, agricultural (farming), education, restoration, cultural heritage, soil conservation / biodiversity, climatic change etc. Other main interests were also to propose some common scientific projects and the development of students exchanges. This communication presents the synthesis of our four meetings held at Draix, Zaragoza, Almeriá and Rouen and some perspectives to continue this network.

  10. 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.

  11. Fungicides transport in runoff from vineyard plot and catchment: contribution of non-target areas.

    Science.gov (United States)

    Lefrancq, Marie; Payraudeau, Sylvain; García Verdú, Antonio Joaquín; Maillard, Elodie; Millet, Maurice; Imfeld, Gwenaël

    2014-04-01

    Surface runoff and erosion during the course of rainfall events are major processes of pesticides transport from agricultural land to aquatic ecosystem. These processes are generally evaluated either at the plot or the catchment scale. Here, we compared at both scales the transport and partitioning in runoff water of two widely used fungicides, i.e., kresoxim-methyl (KM) and cyazofamid (CY). The objective was to evaluate the relationship between fungicides runoff from the plot and from the vineyard catchment. The results show that seasonal exports for KM and CY at the catchment were larger than those obtained at the plot. This underlines that non-target areas within the catchment largely contribute to the overall load of runoff-associated fungicides. Estimations show that 85 and 62 % of the loads observed for KM and CY at the catchment outlet cannot be explained by the vineyard plots. However, the partitioning of KM and CY between three fractions, i.e., the suspended solids (>0.7 μm) and two dissolved fractions (i.e., between 0.22 and 0.7 µm and plot scales enable to evaluate the sources areas of pesticide off-site transport.

  12. Controls on groundwater response and runoff source area dynamics in a snowmelt-dominated montane catchment

    Directory of Open Access Journals (Sweden)

    R. S. Smith

    2013-02-01

    Full Text Available The role of spatial variability in water inputs on runoff source area dynamics has generally not received as much research attention as topography and soils; however, the influence of topography and forest cover on snow surface energy exchanges can result in asynchronous snowmelt throughout a catchment complicating the space-time patterns of runoff generation. This study investigates temporal variation in the relative importance of spatial controls on the occurrence, timing, and persistence of shallow groundwater response utilizing a highly distributed monitoring network in a snowmelt-dominated montane catchment in western Canada. The study findings indicate that deep soil hydraulic conductivity is a first-order control on the distribution of sites that generate shallow groundwater response versus sites that experience only deep percolation. Upslope contributing area and slope gradient are first-order controls on the persistence of groundwater response during peak flow, recession flow, and low flow periods. Runoff source areas expand and contract throughout these periods according to an interplay between catchment wetness and the spatial patterns of topographic convergence. However, controls on the differential timing, intensity, and quantity of snowmelt and controls on vertical versus lateral flux partitioning in the soil overwhelm the influence of topographic convergence on runoff source area dynamics during early spring freshet periods. The study findings suggest that various topographic indices and topography-based rainfall runoff models are not necessarily applicable to modelling snowmelt runoff source area dynamics during all streamflow periods for snowmelt-dominated montane catchments.

  13. 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.

  14. An appraisal of the CORINE land cover database in airport catchment area analysis using GIS approach

    NARCIS (Netherlands)

    P. Suau-Sanchez; G. Burghouwt; M. Pallarres-Barbera

    2014-01-01

    This paper presents a free available dataset, the CORINE land cover that helps dealing with the biases caused by pre-defined and heterogeneous census district boundaries in airport catchment area analysis in Europe. Using this dataset and a conventional GIS software it is possible to measure the siz

  15. Mapping Model of Groundwater Catchment Area based on Geological Fault : Case Study in Semarang City

    Directory of Open Access Journals (Sweden)

    Qudus, N.

    2016-04-01

    Full Text Available Groundwater is a naturally renewable resource because groundwater is an integral part of hydrological cycle. However, in reality, there are many limiting factors which influence its usage, in both quality and quantity, the provision ability of groundwater will decrease if its availability is exceeded. The problems of ground water potential in both quantity and quality are always related to its constituents' characteristics or its geological element where the groundwater resides. This present study aims at determining the groundwater catchment area based on the geological condition of an area so that groundwater recharge can be accomplished. In addition, it is necessary for groundwater catchment area to comply with the geological condition. The geologically unfit area will only result in land movement or landslide if it is used as groundwater catchment area. The results of geo-electricity analysis which was conducted in Semarang city showed that there are 3 faults; Sukorejo fault, Tinjomoyo fault and Jangli fault which will be explained in detail in the paper. Those faults intersect the underground water stream in Semarang from south to north towards the Java Sea. The majority of underground water stream in Semarang flows from south to north. In contrary, the results of the analysis showed that there are some points that become local basins such as in the south area and southwest of Semarang where flow direction is on the opposite direction. In addition, the results of the analysis showed that some coastal areas in Semarang have experienced salt water intrusion.

  16. Evaluation and assessment of water quality in Likangala River and its catchment area

    Science.gov (United States)

    Chidya, R. C. G.; Sajidu, S. M. I.; Mwatseteza, J. F.; Masamba, W. R. L.

    Likangala is one of the perennial rivers in Malawi that flow into a closed Lake Chilwa, a designated wetland ratified by Ramsar Convention in 1997. Earlier work conducted on this river revealed considerable social-economic activities at riverbanks resulting in indiscriminate disposal of wastes. This study intended to evaluate water quality in Likangala River and its catchment area. Water samples were collected thrice (dry, early rainy and mid rainy seasons) and tested for major physico-chemical and microbiological parameters. The EC, pH, and selected ions ( NO3-, PO43-, Na +, K +, Mg 2+, and Ca 2+) were analysed in soil samples obtained in crop fields along the river banks. Elevated EC levels (>1035.00 μS/cm) were measured during mid rainy season at site S15 (Zomba Sewage Works), near and in the lake. Most of the water samples (86%, n = 28) registered phosphate levels above 1.50 mg/L during mid rainy season with a maximum value (10.70 ± 0.01 mg/L) at site S15. Lower amounts (behavioural change and integrated control of water, land use and waste management in order to prevent escalation of the effects.

  17. Energetic Equipment in the Romanian Tisa Catchment Area

    Directory of Open Access Journals (Sweden)

    DINU ZAHARESCU

    2010-01-01

    Full Text Available The article presents the context of energetic equipment in the TICAD area, traditional and alternative sources of energy, and includes a short presentation and the possibilities of use for each of them

  18. Energetic Equipment in the Romanian Tisa Catchment Area

    OpenAIRE

    DINU ZAHARESCU

    2010-01-01

    The article presents the context of energetic equipment in the TICAD area, traditional and alternative sources of energy, and includes a short presentation and the possibilities of use for each of them

  19. Heavy metals in the Ljubljanica catchment area (Slovenia)

    OpenAIRE

    Branka Trček

    2006-01-01

    In main springs and swallowholes of the Ljubljanica River Basin the monitoring of heavy metals was established at the beginning of 2005 with the intention to study the solute transport in the water body and to analyse the risk of contamination with heavy metals. The results of the first monitoring phase are presented–elements that indicate the load of environment due to industry, traffic,agriculture and urbanisation:Al,As,Cd,Cl,Cr,Cu,Mn in Pb. The results point out that the vulnerability of k...

  20. Process-based modelling of a headwater catchment in a semi-arid area : The influence of macropore flow

    NARCIS (Netherlands)

    van Schaik, N. L M B; Bronstert, A.; de Jong, S. M.; Jetten, V. G.; van Dam, J. C.; Ritsema, C. J.; Schnabel, S.

    2014-01-01

    Subsurface stormflow is thought to occur mainly in humid environments with steep terrains. However, in semi-arid areas, preferential flow through macropores can also result in a significant contribution of subsurface stormflow to catchment runoff for varying catchment conditions. Most hydrological m

  1. Heavy metals in the Ljubljanica catchment area (Slovenia

    Directory of Open Access Journals (Sweden)

    Branka Trček

    2006-12-01

    Full Text Available In main springs and swallowholes of the Ljubljanica River Basin the monitoring of heavy metals was established at the beginning of 2005 with the intention to study the solute transport in the water body and to analyse the risk of contamination with heavy metals. The results of the first monitoring phase are presented–elements that indicate the load of environment due to industry, traffic,agriculture and urbanisation:Al,As,Cd,Cl,Cr,Cu,Mn in Pb. The results point out that the vulnerability of karst aquifers depends on aquifer hydrodynamic conditions, infiltration conditions and development of a karst drainage system. Furthermore, they indicated the local and regional geochemical and hydrogeological characteristics and enable to evidence the main processes and effects that impact on environmental changes.

  2. Catchment conceptualisation for examining applicability of chloride mass balance method in an area with historical forest clearance

    Directory of Open Access Journals (Sweden)

    H. Guan

    2010-07-01

    Full Text Available Of the various approaches for estimating groundwater recharge, the chloride mass balance (CMB method is one of the most frequently used, especially for arid and semiarid regions. Widespread native vegetation clearance, common in many areas globally, has changed the land surface boundary condition, posing the question as to whether the current system has reached new chloride equilibrium, required for a CMB application. Although a one-dimensional CMB can be applied at a point where the water and chloride fluxes are locally in steady state, the CMB method is usually applied at a catchment scale owing to significant lateral flows in mountains. The applicability of the CMB method to several conceptual catchment types of various chloride equilibrium conditions is examined. The conceptualisation, combined with some local climate conditions, is shown to be useful in assessing whether or not a catchment has reached new chloride equilibrium. The six conceptual catchment types are tested with eleven selected catchments in the Mount Lofty Ranges (MLR, a coastal hilly area in South Australia having experienced widespread historical forest clearance. The results show that six of the eleven catchments match a type VI chloride balance condition (chloride non-equilibrium with a gaining stream, with the ratios of stream chloride output (O over atmospheric chloride input (I, or catchment chloride O/I ratios, ranging from 2 to 4. Two catchments match a type V chloride balance condition (chloride non-equilibrium with a losing stream, with catchment chloride O/I ratios about 0.5. For these type V and type VI catchments, the CMB method is not applicable. The results also suggest that neither a chloride O/I ratio less than one nor a low seasonal fluctuation of streamflow chloride concentration (a factor below 4 guarantees a chloride equilibrium condition in the study area. A large chloride O/I value (above one and a large fluctuation of streamflow chloride

  3. Catchment conceptualisation for examining applicability of chloride mass balance method in an area of historical forest clearance

    Directory of Open Access Journals (Sweden)

    H. Guan

    2009-11-01

    Full Text Available Among various approaches for estimating groundwater recharge, chloride mass balance (CMB method is one of the most frequently used, in particular, for arid and semiarid regions. Widespread native vegetation clearance, common history in many areas globally, has changed land surface boundary condition, posing a question whether the current system has reached new chloride equilibrium for CMB application. To examine CMB applicability for catchments, conceptual catchment types of various chloride equilibrium conditions are defined. The conceptualization, combined with some local climate conditions, is demonstrated to be useful in examining whether a catchment has reached new chloride equilibrium. The six conceptual catchment types are tested with eleven selected catchments in the Mount Lofty Ranges (MLR, a coastal hilly area in South Australia having experienced historical widespread forest clearance. The results show that six of the eleven catchments match type VI chloride balance condition (chloride non-equilibrium with a gaining stream, with the ratio of stream chloride output over atmospheric chloride input (catchment chloride O/I ranging from 2 to 4. Two catchments match type V chloride balance condition (chloride non-equilibrium with a losing stream, with catchment chloride O/I values about 0.5. For these catchments, the CMB method is not appropriate to apply. The results also suggest that neither a below-one chloride O/I value nor a low seasonal fluctuation of streamflow chloride concentration (a factor below 4 guarantees a chloride equilibrium condition in the study area. But a large chloride O/I value (above one and a large fluctuation of streamflow chloride concentration (a factor of 10 and above generally indicates either a chloride disequilibrium, or cross-catchment water transfer, or both, for which CMB is not applicable. Based on the regression between chloride O/I values and annual precipitation for type VI catchments, a catchment with

  4. The Territory of the Tisa Catchment Area between Natural and Functional Organization

    OpenAIRE

    POMPEI COCEAN

    2010-01-01

    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...

  5. Analysing the role of abandoned agricultural terraces on flood generation in a set of small Mediterranean mountain research catchments (Vallcebre, NE Spain)

    Science.gov (United States)

    Gallart, Francesc; Llorens, Pilar; Pérez-Gallego, Nuria; Latron, Jérôme

    2016-04-01

    The Vallcebre research catchments are located in NE Spain, in a middle mountain area with a Mediterranean sub-humid climate. Most of the bedrock consists of continental red lutites that are easily weathered into loamy soils. This area was intensely used for agriculture in the past when most of the sunny gentle hillslopes were terraced. The land was progressively abandoned since the mid-20th Century and most of the fields were converted to meadows or were spontaneously forested. Early studies carried out in the terraced Cal Parisa catchment demonstrated the occurrence of two types of frequently saturated areas, ones situated in downslope locations with high topographic index values, and the others located in the inner parts of many terraces, where the shallow water table usually outcrops due to the topographical modifications linked to terrace construction. Both the increased extent of saturated areas and the role of a man-made elementary drainage system designed for depleting water from the terraces suggested that terraced areas would induce an enhanced hydrological response during rainfall events when compared with non-terraced hillslopes. The response of 3 sub-catchments, of increasing area and decreasing percentage of terraced area, during a set of major events collected during over 15 years has been analysed. The results show that storm runoff depths were roughly proportional to precipitations above 30 mm although the smallest catchment (Cal Parisa), with the highest percentage of terraces, was able to completely buffer rainfall events of 60 mm in one hour without any runoff when antecedent conditions were dry. Runoff coefficients depended on antecedent conditions and peak discharges were weakly linked to rainfall intensities. Peak lag times, peak runoff rates and recession coefficients were similar in the 3 catchments; the first variable values were in the range between Hortonian and saturation overland flow and the two last ones were in the range of

  6. Perylene in Lake Biwa sediments originating from Cenococcum geophilum in its catchment area

    Science.gov (United States)

    Itoh, Nobuyasu; Sakagami, Nobuo; Torimura, Masaki; Watanabe, Makiko

    2012-10-01

    Perylene, which is composed of five benzene rings, is commonly found in sediments throughout the world at concentrations and distributions that are different from those of other polycyclic aromatic hydrocarbons. The only information available on the origin of perylene comes from 4,9-dihydroxyperylene-3,10-quinone (DHPQ), which originates from fungal component symbiosis or from parasites on plants; however, there is no direct evidence of a mechanism of perylene formation. In this study, we examined the relationship between sedimentary perylene and Cenococcum geophilum (C. geophilum) in a catchment area at Lake Biwa. Sclerotium grains of C. geophilum containing DHPQ were found in this catchment area (approximately 40 balls kg-1 dried soil for >1 mm-ϕ), and small sclerotium grains were frequently found in the sediment. In the sediment sample, we also found broken particles containing perylene, and they had a porous structure characteristic of sclerotium grains. Furthermore, the particles contained DHPQ in different transformation stages to perylene via 3,10-perylenequinone (3,10-PQ). This finding was consistent with results from elemental analysis (oxygen/carbon). Because a remarkable amount of DHPQ originating from C. geophilum also exists in the humic acids of soils and because the inputs of compounds to the lake depend strongly on the rivers, perylene in the Lake Biwa sediment originates mainly from the DHPQ of C. geophilum in its catchment area.

  7. Hyporheic flow pattern based on the coupling of regional and stream scales: Case of Krycklan Catchment area

    Science.gov (United States)

    Mojarrad, Morteza; Wörman, Anders; Riml, Joakim

    2016-04-01

    defined in terms of spatial statistics of the vertical flow velocity and quantified in terms of correlation length in a semi-variance analyses. The river bed elevation represents range of wavelengths of relevance for controlling the upwelling of deeper groundwater (not originating from the stream flow). Based on the relation between topographical amplitudes of harmonic (Fourier) functions, the exchange velocity in hyporheic zone can be calculated exactly. Finally, by superposing these two models and analyzing the results of both large scale and small scale including the pressure head, hyporheic exchange; show a distinct effect of the large scale groundwater flow on the small scale hyporheic flow velocity in Krycklan catchment area.

  8. Improved methods to estimate the effective impervious area in urban catchments using rainfall-runoff data

    Science.gov (United States)

    Ebrahimian, Ali; Wilson, Bruce N.; Gulliver, John S.

    2016-05-01

    Impervious surfaces are useful indicators of the urbanization impacts on water resources. Effective impervious area (EIA), which is the portion of total impervious area (TIA) that is hydraulically connected to the drainage system, is a better catchment parameter in the determination of actual urban runoff. Development of reliable methods for quantifying EIA rather than TIA is currently one of the knowledge gaps in the rainfall-runoff modeling context. The objective of this study is to improve the rainfall-runoff data analysis method for estimating EIA fraction in urban catchments by eliminating the subjective part of the existing method and by reducing the uncertainty of EIA estimates. First, the theoretical framework is generalized using a general linear least square model and using a general criterion for categorizing runoff events. Issues with the existing method that reduce the precision of the EIA fraction estimates are then identified and discussed. Two improved methods, based on ordinary least square (OLS) and weighted least square (WLS) estimates, are proposed to address these issues. The proposed weighted least squares method is then applied to eleven urban catchments in Europe, Canada, and Australia. The results are compared to map measured directly connected impervious area (DCIA) and are shown to be consistent with DCIA values. In addition, both of the improved methods are applied to nine urban catchments in Minnesota, USA. Both methods were successful in removing the subjective component inherent in the analysis of rainfall-runoff data of the current method. The WLS method is more robust than the OLS method and generates results that are different and more precise than the OLS method in the presence of heteroscedastic residuals in our rainfall-runoff data.

  9. Long-term hydrometeorological measurements and model-based analyses in the hydrological research catchment Rietholzbach

    OpenAIRE

    Gurtz, J.; Verbunt, M.; Zappa, M.; Moesch, M.; Pos, F.; Moser, U.

    2003-01-01

    In this study a 25-year (1976–2000) series of observed precipitation, temperature, runoff and further water-flows of a lysimeter balance within the pre-alpine research catchment Rietholzbach (Switzerland) is analyzed. The comparison of the precipitation volumes on this lysimeter to precipitation collected by a conventional rain gauge shows that conventional rain gauges provide strongly underestimated values for precipitation, especially in winter. The obtained monthly precipitation correction...

  10. Hydrologic and biogeochemical functioning of intensively managed catchments: A synthesis of top-down analyses

    Science.gov (United States)

    Basu, Nandita B.; Thompson, Sally E.; Rao, P. Suresh C.

    2011-10-01

    This paper synthesizes a 3-year collaborative effort to characterize the biogeochemical and hydrological features of intensively managed agricultural catchments by combining data analysis, modeling, and preliminary hypothesis testing. The specific focus was on the Midwestern region of the United States. The results suggest that: (1) water management, specifically the homogenization of evapotranspiration losses driven by mono-cultural vegetation cover, and the homogenization of runoff generation driven by artificial drainage, has created engineered, predictable hydrologic systems; (2) nutrient and pesticide management, specifically their regular applications have created two kinds of biogeochemical export regimes: chemostatic (low variability in concentration as exhibited by nitrate) and episodic (high variability in concentration as exhibited by pesticides); (3) coupled mass-balance models for water and solutes reproduce these two regimes as a function of chemical rate constants. Phosphorus transport regimes were found to be episodic at smaller spatial scales, but chemostatic at larger scales. Chemostatic response dominates in transport-limited catchments that have internal sources of the solute to buffer the periodicity in episodic inputs, while episodic response dominates in source-limited catchments. The shift from episodic nitrate export in pristine catchments to chemostatic regimes in managed watersheds was attributed to legacy stores of nitrogen (built from continued fertilizer applications) that buffer interannual variations in biogeochemical processing. Fast degradation kinetics of pesticides prevents the build-up of legacy sources, and leads to episodic export. Analytical expressions were derived for the probability density functions of solute delivery ratio as a function of the stochastics of rainfall-runoff events and biogeochemical controls.

  11. The characteristics of the chemical flow within the Motru catchment area, south — west Romania

    Science.gov (United States)

    Ionuş, Oana

    2011-03-01

    The present paper, with reference to the Motru catchment area, contributes to the hydrochemical studies at an international level and to the completion of the characteristics regarding the chemical flow in Romania. In this regard, it emphasizes once again the dependence between the content of dissolved salts (fixed residue — mg/l) on the one hand and the lithological conditions, human activity, flow and the surface of the catchments on the other hand. The calculation and the analysis of the chemical flow for the Motru catchment area (located in the south-west of Romania) was performed on the basis of two parameters: the average flow of dissolved chemical substances (mg/s) and specific average chemical flow (t/kmp year) recorded at the monitoring stations on the Motru River and its tributaries during the period 2005-2009. The values obtained (for example: 2.63 mg/s and 47.7 t/km2 year, at the Fata Motrului station, on the Motru River, in 2009) confirm the importance of the areal factors of natural background in the analysis of chemical flow as a morpho-dynamic process and implicitly for the chemical quality of surface waters.

  12. Comprehensive determinants of health service utilisation for mental health reasons in a canadian catchment area

    Directory of Open Access Journals (Sweden)

    Fleury Marie-Josée

    2012-04-01

    Full Text Available Abstract Introduction This study sought to identify factors associated with health service utilisation by individuals with mental disorders in a Canadian catchment area. Methods To be included in the study, participants had to be aged between 15 and 65 and reside in the study location. Data was collected randomly from June to December 2009 by specially trained interviewers. A comprehensive set of variables (including geospatial factors was studied using the Andersen's behavioural health service model. Univariate, bivariate, and multivariate analyses were carried out. Results Among 406 individuals diagnosed with mental disorders, 212 reported using a mental health service at least once in the 12 months preceding the interviews. Emotional problems and a history of violence victimisation were most strongly associated with such utilisation. Participants who were middle-aged or deemed their mental health to be poor were also more likely to seek mental healthcare. Individuals living in neighbourhoods where rental accommodations were the norm used significantly fewer health services than individuals residing in neighbourhoods where homeownership was preponderant; males were also less likely to use services than females. Conclusions Our study broke new ground by uncovering the impact of longstanding violence victimisation, and the proportion of homeownership on mental health service utilisation among this population. It also confirmed the prominence of some variables (gender, age, emotional problems and self-perceived mental health as key enabling variables of health-seeking. There should be better promotion of strategies designed to change the attitudes of males and youths and to deal with violence victimisation. There is also a need for initiatives that are targeted to neighbourhoods where there is more rental housing.

  13. Determining the groundwater potential recharge zone and karst springs catchment area: Saldoran region, western Iran

    Science.gov (United States)

    Karami, Gholam Hossein; Bagheri, Rahim; Rahimi, Fahimeh

    2016-08-01

    Assessing the groundwater recharge potential zone and differentiation of the spring catchment area are extremely important to effective management of groundwater systems and protection of water quality. The study area is located in the Saldoran karstic region, western Iran. It is characterized by a high rate of precipitation and recharge via highly permeable fractured karstic formations. Pire-Ghar, Sarabe-Babaheydar and Baghe-rostam are three major karstic springs which drain the Saldoran anticline. The mean discharge rate and electrical conductivity values for these springs were 3, 1.9 and 0.98 m3/s, and 475, 438 and 347 μS/cm, respectively. Geology, hydrogeology and geographical information system (GIS) methods were used to define the catchment areas of the major karstic springs and to map recharge zones in the Saldoran anticline. Seven major influencing factors on groundwater recharge rates (lithology, slope value and aspect, drainage, precipitation, fracture density and karstic domains) were integrated using GIS. Geology maps and field verification were used to determine the weights of factors. The final map was produced to reveal major zones of recharge potential. More than 80 % of the study area is terrain that has a recharge rate of 55-70 % (average 63 %). Evaluating the water budget of Saldoran Mountain showed that the total volume of karst water emerging from the Saldoran karst springs is equal to the total annual recharge on the anticline. Therefore, based on the geological and hydrogeological investigations, the catchment area of the mentioned karst springs includes the whole Saldoran anticline.

  14. Simulating nitrogen budgets in complex farming systems using INCA: calibration and scenario analyses for the Kervidy catchment (W. France)

    Science.gov (United States)

    Durand, P.

    The integrated nitrogen model INCA (Integrated Nitrogen in Catchments) was used to analyse the nitrogen dynamics in a small rural catchment in Western France. The agrosystem studied is very complex, with: extensive use of different organic fertilisers, a variety of crop rotations, a structural excess of nitrogen (i.e. more animal N produced by the intensive farming than the N requirements of the crops and pastures), and nitrate retention in both hydrological stores and riparian zones. The original model features were adapted here to describe this complexity. The calibration results are satisfactory, although the daily variations in stream nitrate are not simulated in detail. Different climate scenarios, based on observed climate records, were tested; all produced a worsening of the pollution in the short term. Scenarios of alternative agricultural practices (reduced fertilisation and catch crops) were also analysed, suggesting that a reduction by 40% of the fertilisation combined with the introduction of catch crops would be necessary to stop the degradation of water quality.

  15. Simulating nitrogen budgets in complex farming systems using INCA: calibration and scenario analyses for the Kervidy catchment (W. France

    Directory of Open Access Journals (Sweden)

    P. Durand

    2004-01-01

    Full Text Available The integrated nitrogen model INCA (Integrated Nitrogen in Catchments was used to analyse the nitrogen dynamics in a small rural catchment in Western France. The agrosystem studied is very complex, with: extensive use of different organic fertilisers, a variety of crop rotations, a structural excess of nitrogen (i.e. more animal N produced by the intensive farming than the N requirements of the crops and pastures, and nitrate retention in both hydrological stores and riparian zones. The original model features were adapted here to describe this complexity. The calibration results are satisfactory, although the daily variations in stream nitrate are not simulated in detail. Different climate scenarios, based on observed climate records, were tested; all produced a worsening of the pollution in the short term. Scenarios of alternative agricultural practices (reduced fertilisation and catch crops were also analysed, suggesting that a reduction by 40% of the fertilisation combined with the introduction of catch crops would be necessary to stop the degradation of water quality. Keywords: diffuse pollution, nitrate, climate change, model

  16. Seasonal variability of suspended sediment transport in the Seine river catchment area (France)

    Science.gov (United States)

    Franke, Christine; Baati, Selma; Ayrault, Sophie; Bonte, Philippe; Evrard, Olivier; Kissel, Catherine

    2010-05-01

    This study consists in an innovative application of environmental physico-chemical techniques on fluvial sediments with the aim to trace the seasonal changes in suspended sediment transport of the complex Seine river catchment area in northern France. The aim of this project is to develop a detailed understanding for the discrimination of naturally triggered and anthropogenic induced processes and their temporal changes with weather conditions. With a focus on the heavy metal fraction, we determine the regional distribution of the suspended material and search for environmental fingerprints demonstrating the influence of fluvial transport mechanisms, changes in concentration related to discharge variations or different sediment sources, and in-situ alteration caused by variations in the geochemical conditions (oxy-redox, pH, Eh, etc.). To achieve these goals, we apply a combination of straightforward rock magnetic hysteresis measurements (performed using an AGM2900 at the LSCE) and advanced scanning electron microscopy analyses (SEM). This interdisciplinary approach allows refining the detailed analysis of sediment trap samples, originating from Tessier et al. (2003), as recently shown by Franke et al. (2009). In our preliminary results, we observe a general increase in magnetic concentrations from summer to winter conditions, coupled with a magneto-mineralogic change to rather reduced metallic mineral phases. However, each riversection of the Seine system shows its specific trend line depending on the regional initial input, weathering conditions, drainage area and potential pollution sources. A systematic analysis of the detailed results will allow highlighting the climatic/seasonal influence on the metallic particle assembly. Keywords: Seine river system, environmental magnetism, suspended particulate matter, anthropogenic and natural input, magnetic hysteresis, scanning electron microscopy (SEM),, heavy metal pollution, seasonal variability References: Franke

  17. Catchment conceptualisation for examining applicability of chloride mass balance method in an area of historical forest clearance

    OpenAIRE

    H. Guan; Love, A.; C. T. Simmons; Ding, Z; Hutson, J

    2009-01-01

    Among various approaches for estimating groundwater recharge, chloride mass balance (CMB) method is one of the most frequently used, in particular, for arid and semiarid regions. Widespread native vegetation clearance, common history in many areas globally, has changed land surface boundary condition, posing a question whether the current system has reached new chloride equilibrium for CMB application. To examine CMB applicability for catchments, conceptual catchment types of various chloride...

  18. IMPACT OF URBANISATION ON LANDUSE IN A PERI-URBAN, CHENNAI – A CASE STUDY OF CATCHMENT AND COMMAND AREA OF CHEMBARAMBAKKAM TANK

    Directory of Open Access Journals (Sweden)

    S. DHATCHAYANI

    2013-04-01

    Full Text Available Water plays a vital role in the developmental activities of any country. Present mismanagement of water resources causes future deterioration, both in quantity and quality. Increase in population causes changes in the landuse / landcover in the peri-urban areas. The Chembarambakkam tank taken for study has recently been developed as a major source of water supply to the Chennai city. It has maximum storage capacity of 103 MFt. The major treatment plant of 530 MLD has been commissioned on July 2007. It is necessary to safeguard the existing water resources and analyse the present status of the water body. The catchment area contributes to the inflow and the quantity of water is analysed by estimating the runoff from the catchment area using Soil Conservation Services – Curve Number (SCS-CN model. Water released to the command area for irrigation is analysed from the secondary data. The landuse / landcover change in the command area was identified by comparing the satellite imageries of the years 1991 and 2003. Questionnaire and Participatory Rural Appraisal (PRA tools like village mapping and time – line analysis were used to get the social and economic data to analyse the reasons for changes in landuse. This project proves that urbanization and industrialization has reduced the irrigation to the worst level.

  19. Complex gravity zones and the extension of labour catchment areas in North Transdanubia

    Directory of Open Access Journals (Sweden)

    Tamás Hardi

    2014-12-01

    Full Text Available The goals of this study are the identification of the centres of gravity of the Northern-Transdanubian cities, including Győr, by using a gravitation model and, based on empirical examination, the definition of manpower catchment areas. Then, we are going to analyze the impact fields determined by two methods and seek explanations for the overlaps and differences of the two delineations, which are also going to be analyzed with the consideration of geographic, social and economic factors. Both examinations were carried out at two dates, covering a timeframe of 10 years.

  20. Job loss and alcohol abuse: a test using data from the Epidemiologic Catchment Area project.

    Science.gov (United States)

    Catalano, R; Dooley, D; Wilson, G; Hough, R

    1993-09-01

    The hypothesis that job loss affects the incidence of clinically significant alcohol abuse is tested using panel data from the Epidemiologic Catchment Area project. Results suggest that the incidence of clinically significant alcohol abuse is greater among those who have been laid off than among those who have not. However, employed persons in communities in which total employment is unexpectedly low are at reduced risk of becoming alcohol abusers. The implications of the results for economic policy and for mental health services are discussed briefly. PMID:7989666

  1. Integration of neural networks in a geographical information system for the monitoring of a catchment area

    OpenAIRE

    Thiéry, Frédérik; Grieu, Stéphane; Traoré, Adama; Barreau, Mathieu; Polit, Monique

    2008-01-01

    International audience The present work takes part in a global development of reliable and robust tools allowing real-time controlling and supervising of the Têt catchment area, the main river of the Pyrénées-Orientales department (Southern France). The impact of the Têt on the department life is significant and the management of its water quality must be largely improved and better supervised. The main purpose of the work was to develop "rain flow" predictive models, using Elman recurrent...

  2. Long term effect of metal pollution in the catchment area of Tisza River

    Directory of Open Access Journals (Sweden)

    Zoltán Győri

    2013-01-01

    Full Text Available In January and March 2000 two tailings dam failures occurred in the upper Tisza catchment area near Baia Mare and Baia Borsa (Romania. These accidents focused attention on the metal pollution of the Tisza catchment area, and the short term effects of them were studied by many researchers. The aim of this study was to evaluate the long term effects of these pollutions by determining the Lakanen-Erviö extractable easily available metal contents of samples collected in 2011 from floodplains and pastures along the Tisza (Tivadar, Vásárosnamény, Rakamaz, Tiszacsege, and comparing them to our earlier results. Cu and Zn contents were measured by Optima 3300 DV ICP-OES (Perkin-Elmer. The measurement of Pb and Cd was conducted by QZ 939 GF-AAS (Unicam in 2000 and by an X7 ICP-MS (Thermo Fisher in 2011. We found that the Cd, Zn and Pb contents of the pasture near Vásárosnamény exceed limit values and natural background values. In addition, during a 11 year period the easily available Cd, Zn and Pb contents increased significantly, suggesting that the hazard of this pollution should not be neglected.

  3. Hydrological response of afforestation in a Mediterranean mountain area: the Araguás Afforestation catchment

    Science.gov (United States)

    Nadal Romero, Estela; Cammeraat, Erik; Serrano Muela, Pili; Lana-Renault, Noemi; Regüés, David

    2015-04-01

    The fraction of forest cover in the Mediterranean region is increasing due to afforestation programs conducted by national forest services and also due to natural revegetation processes. Literature review suggests that afforestation might threaten water resources because it (i) reduces the number of floods and many rainfall events produce no notable flow; (ii) decreases annual water yield and low flows; (iii) delays peak flows but increases the duration of floods; and (iv) increases rainfall interception, reducing the water reaching the soil. Also, afforestation typically reduces erosion risk and the volume of sediment reaching the streams, but not during the first years after plantation due to high geomorphic activity when invasive techniques are used. Although the great amount of literature on these topics, there is still considerable scientific uncertainty about the impact of afforestation on extreme events and groundwater dynamics. The MED-AFFOREST project studies the effects of afforestation on the hydrological response of a small catchment (Araguás afforestation catchment) monitored in the Central Spanish Pyrenees. In this study, we present the first results , as an example of the likely effects of afforestation in Mediterranean mountain areas. The results show that the hydrological response in the afforestation area is variable and complex, because the discharge was generated by a combination of different runoff generation processes. Acknowledgments This research was supported by a Marie Curie Intra-European Fellowship in the project "MED-AFFOREST" (PIEF-GA-2013-624974).

  4. River runoff and regional climate of a small glaciated catchment area in the Andes in southernmost Patagonia, Chile

    Science.gov (United States)

    Schneider, C.; Moritz, M.; Kilian, R.

    2003-04-01

    The river runoff from a small partly glaciated catchment area in southernmost Patagonian Andes in Chile is measured to analyse the influence of regional precipitation and climate dependent glacier ablation on runoff. The first data from March to September 2002 were compared to climate data recorded at an automatic weather station in the area. The poster presents the first detailed hydrometeorological investigation from this part of the Andes. The investigation area is located at 53°S in southernmost South America exactly east of the main divide of the mountain range of the Andes at 72.5°W. The catchment area of about 15 km2 comprises parts of the Gran Campo Nevado Ice Cap reaching up to 1500 m asl, and the outlet glacier Glaciar Lengua which ends at a proglacial lake at 100 m asl. The Gran Campo Nevado Ice Cap is the major ice mass between the Southern Patagonian Ice field in the north and the Strait of Magallan to the South. Climate in the area is characterised by whole-year round cool and super-humid conditions with a mean annual air temperature of 5,6°C at sea level and an annual precipitation sum of approximately 7,000 mm. The Río Lengua itself meets approximately 3.5 km downstreams from the proglacial lake into the fjord system of Canal Garjado which is a branch of Seno Skyring. A continuous hourly record of water levels in the river was obtained from two digital water depth sensors. Runoff was calibrated against river level by measuring runoff at different times with the tracer method of salt dilution and with velocity measurements employing a hydrometric vane. Mean runoff was computed to about 3 m3/s with peak flows exceeding 10 m3/s. Ablation on the glacier was estimated using the degree-day method with a degree-day factor that has been calibrated previously using data from a temporal energy balance weather station on Glacíar Lengua. The correlation between runoff and air temperature and precipitation returned significant correlation coefficients of rt

  5. An Enhanced Variable Two-Step Floating Catchment Area Method for Measuring Spatial Accessibility to Residential Care Facilities in Nanjing

    Directory of Open Access Journals (Sweden)

    Jianhua Ni

    2015-11-01

    Full Text Available Civil administration departments require reliable measures of accessibility so that residential care facility shortage areas can be accurately identified. Building on previous research, this paper proposes an enhanced variable two-step floating catchment area (EV2SFCA method that determines facility catchment sizes by dynamically summing the population around the facility until the facility-to-population ratio (FPR is less than the FPR threshold (FPRT. To minimize the errors from the supply and demand catchments being mismatched, this paper proposes that the facility and population catchment areas must both contain the other location in calculating accessibility. A case study evaluating spatial accessibility to residential care facilities in Nanjing demonstrates that the proposed method is effective in accurately determining catchment sizes and identifying details in the variation of spatial accessibility. The proposed method can be easily applied to assess other public healthcare facilities, and can provide guidance to government departments on issues of spatial planning and identification of shortage and excess areas.

  6. THE MONITORING OF SURFACE WATER BODIES (RIVERS FROM TISA CATCHMENT AREA - MARAMUREŞ COUNTY IN 2014

    Directory of Open Access Journals (Sweden)

    GABRIELA ANDREEA DESPESCU

    2016-03-01

    Full Text Available This study is focused on the monitoring and evaluation of river’s water bodies from Maramureş County, using the methodology associated with the EU Water Framework Directive 60/2000. Thus, in the first part are defined the theoretical terms of monitoring activities related to the water bodies’ quality and the specific features of those we can find in the studied area. There are presented the water bodies’ features, quality indicators and the monitoring frequencies for the rivers situated in the Tisa catchment area. The results have shown the actual ecological and chemical state of those water bodies, in relation with the standard values mentioned through the Water Framework Directive.

  7. Spatial accessibility of primary health care utilising the two step floating catchment area method: an assessment of recent improvements

    Directory of Open Access Journals (Sweden)

    McGrail Matthew R

    2012-11-01

    Full Text Available Abstract Background The two step floating catchment area (2SFCA method has emerged in the last decade as a key measure of spatial accessibility, particularly in its application to primary health care access. Many recent ‘improvements’ to the original 2SFCA method have been developed, which generally either account for distance-decay within a catchment or enable the usage of variable catchment sizes. This paper evaluates the effectiveness of various proposed methods within these two improvement groups. Moreover, its assessment focuses on how well these improvements operate within and between rural and metropolitan populations over large geographical regions. Results Demonstrating these improvements to the whole state of Victoria, Australia, this paper presents the first comparison between continuous and zonal (step decay functions and specifically their effect within both rural and metropolitan populations. Especially in metropolitan populations, the application of either type of distance-decay function is shown to be problematic by itself. Its inclusion necessitates the addition of a variable catchment size function which can enable the 2SFCA method to dynamically define more appropriate catchments which align with actual health service supply and utilisation. Conclusion This study assesses recent ‘improvements’ to the 2SFCA when applied over large geographic regions of both large and small populations. Its findings demonstrate the necessary combination of both a distance-decay function and variable catchment size function in order for the 2SFCA to appropriately measure healthcare access across all geographical regions.

  8. Model-based quality management of groundwater resources - catchment area Liedern, Germany.

    Science.gov (United States)

    Kübeck, Christine; Hansen, Carsten; König, Christoph; Denzig, Dorothea; van Berk, Wolfgang

    2012-01-01

    Strategies of groundwater protection in agricultural dominated areas are mainly based on a general reduction of the input of nutrients like nitrate. However, preventive measures in different parts of the catchment may provide very different effects on raw water quality. Exemplified on the case study 'Liedern' (BEW GmbH Bocholt, Germany) it is shown that hydrogeochemical processes along the flow path and in the well strongly affect the results of agricultural measures in terms of modality and efficiency. Thus, a reduction of fertilization in the vicinity of the well gallery leads to a decrease of nitrate concentration in the raw water. Whereas agricultural measures in the eastern part of the catchment do not influence nitrate, but cause a reduction of the iron concentration and rate of incrustation in the wells after 18 years. In this study we present a management tool that enables assessment of future trends in raw water quality. The tool is based on a reactive transport model which considers land use dynamics as an instrument to influence groundwater/raw water quality. A thermodynamic equilibrium approach is applied for modelling hydrogeochemical processes between aqueous, solid and gaseous phases. Kinetically controlled reactions like the microbial degradation of organic carbon are expressed by multiplicative Michaelis-Menten equations.

  9. Assessment of Socioeconomic Vulnerability to Floods in the Bâsca Chiojdului Catchment Area

    Directory of Open Access Journals (Sweden)

    REMUS PRĂVĂLIE

    2014-12-01

    Full Text Available Hydrological risk phenomena such as floods are among the most costly natural disasters worldwide, effects consisting of socioeconomic damages and deaths. The Bâsca Chiojdului catchment area, by its morphometric and hydrographic peculiarities, is prone to generate these hydrological risk phenomena, so there is a high vulnerability in the socioeconomic elements. This paper is focused on the identification of the main socioeconomic elements vulnerable to hydrological risk phenomena such as floods, based on the assessment of their manifestation potential. Thus, following the delimitation of areas with the highest flood occurrence potential (susceptibility to floods, major socioeconomic factors existing in the basin, considering human settlements (constructions, transport infrastructure, and agricultural areas (the most important category, were superimposed. Results showed a high vulnerability for all three exposed socioeconomic elements especially in valley sectors, of which household structures were the most vulnerable, given both their importance and the high number of areas highly exposed to floods (approximately 2,500 houses and outbuildings, out of a total of about 10,250, intersect the most susceptible area to floods in the study area.

  10. 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.

  11. Analysis of interrelation between water quality and hydrologic conditions on a small karst catchment area of sinking watercourse Trbuhovica

    International Nuclear Information System (INIS)

    Sinking watercourse Trbuhovica is located at the topping karst of Gorski Kotar in Croatia, near the Slovenian border. About 900 inhabitants live in Trbuhovica catchment area. Sewage system had not been built. The project KEEP WATERS CLEAN (INTERREG III A project) was approved by EU commission and has a purpose of investigating water resources of that area, their appropriate protection and improving management of those resources. This paper presents project's 1st phase investigation results: hydrologic conditions and water quality at several locations on stream and at the springs of Trbuhovica, Mlake and Obrh. Climatologic (precipitation, air temperature and snow cover), basic hydrologic characteristics (flow and water temperature), water quality parameters (pH, electric conductivity, alkalinity, oxygen regime, nutrients and mineral oils) and microbiology indicators have been monitored. Samples of micro invertebrates and samples of periphyton have been collected in the field. Biological results have been elaborated via Saprobial Index according to Pantle-Buck. Analyses results showed a strong connection between hydrologic condition and selected water quality parameters. The groundwater quality changes are very quick. Maximum pollutions occur during the period of intensive rain. Water at the spring of Mlaka is very clean and is classified in the first to second water category, while Trbuhovica shows higher organic pollution.

  12. Abandoned Smolník mine (Slovakia – a catchment area affected by mining activities

    Directory of Open Access Journals (Sweden)

    Lintnerová, Otília

    2008-06-01

    Full Text Available Smolník is a historical Cu-mining area that was exploited from the 14th century to 1990. The Smolník mine was definitively closed and flooded in 1990–1994. Acid mine drainage discharging from the flooded mine (pH = 3.83, Fe = 542 mg/l, SO42– = 3642 mg/l, Cu = 1880 µg/l, Zn = 9599 µg/l, As = 108 mg/l acidified and contaminated the Smolník Creek water, which transported pollution into the Hnilec River catchment. The Smolník mine waste area has been used as a model area to document pollution of waters, stream sediments, and soils by metals and other toxic elements. Major goals of this complex study were to document creek water transport of the main pollutants (Fe, sulphates, Cu, Al, As, etc. in the form of suspended solids, to investigate elements mobility in common mine waste (rock and processing waste heaps and tailing impoundment and in the soil on the basis of neutralization and leach experiments. Different methodologies and techniques for sampling and chemical and mineralogical characterization of samples were used and checked to evaluate environmental risk of this abandoned mine area.

  13. Catchment scale analysis on river-return ratio of irrigation water from densely developed paddy areas

    Science.gov (United States)

    Yoshida, T.; Masumoto, T.; Horikawa, N.; Kudo, R.; Minakawa, H.; Nawa, N.

    2013-12-01

    Irrigation in Japan is predominantly used for rice cultivation, and it accounts for 70% of total water withdrawal. Water loss, which is attributable to nature of open channel irrigation system and percolation from fields, leads to relatively low irrigation efficiencies compared with ones for upland crops. However, because part of water gradually returns to rivers (river-return flow), it contributes to stable water use in downstream. This study investigated how irrigation water circulates and returns to rivers, and quantified a ratio of river-return flow to irrigation intake for an irrigation area (river-return ratio). One difficulty in river-return flow analysis lies in the fact that two types of flow pathways exist in an irrigation area; natural rivers that drain water from the areas, and channel networks whose directions do not necessarily coincide with river directions. In addition, outflux from irrigation area is consisted of water from different sources, such as water loss during water allocation, rainfall, irrigation, and influx from adjacent upstream areas. To cope with such difficulties, we used a grid-based distributed water circulation model that represents both catchment scale hydrological cycles and water flows related to irrigation channel network. The model calculates water flow for irrigation networks based on a GIS database of water use facilities. The model also incorporates operation rules for facilities and field level water management. Using the modeled river network, we first identify grid-cells where influx and outflux occurs across boundaries of irrigation areas. Then, to eliminate the effect of influx from adjacent upstream areas, we subtract influx from outflux. This makes us to capture outflux that purely originates in rainfall and irrigation within an irrigated area. Next, we separate the amount of outflux that originates in irrigation from the total amount of outflux. As residence time of each flow pathway had not been clarified yet, we

  14. Critical Loads of Heavy Metals in a Highly Polluted Catchment Area in Egypt

    Institute of Scientific and Technical Information of China (English)

    Ahmed A. Melegy; T. Paces

    2004-01-01

    Heavy metals in different environmental compartments can be hazardous to ecosystems. Budgets of Cd, Pb and Zn in small ecosystems of the Shubra El-Kheima area in Egypt are presented. The budgets are not in steady state because they change with time. So the concentrations of the metals are a function of time. The critical loads of heavy metals to soils can be calculated from an inventory of inputs and outputs of the trace components in the catchment area. Critical time is an important parameter for critical load evaluation because it can indicate which of the heavy metals may be the most acute threat to the soils. Egyptian soil in the Shubra El-Kheima area seems to be in danger of heavy metal pollution by Zn, Cd and Pb. The calculated critical loads and their exceedances are approximate indicators of the hazards in the soil system. The critical time is a warning signal to initiate an environmental evaluation of possible pollution hazards.

  15. A Mechanistic Assessment of a Near-stream Saturated Area Dynamics in a Headwater Catchment

    Science.gov (United States)

    Frentress, J.; Pfister, L.; McDonnell, J.

    2015-12-01

    Saturation excess overland flow generated in near-stream saturated areas is a mixture of rainfall and exfiltrating sub-surface water that can be quickly transported to the stream network during rainfall events. While many isotope hydrograph separation studies have demonstrated generally the dominance of pre-event water in the channel hydrograph, the mixing processes within the saturated area itself are poorly understood. Here, we isolated and measured discharge generated within a 100-m2 saturated area of a headwater reach of the 45-ha Weierbach catchment (Luxembourg). We quantified surface saturation using ground-based thermal infrared imagery and in-site piezometers throughout a series of rainfall events. This, combined with isotope and geochemical tracing enabled us to assess the role of surface saturation dynamics on mixing and storm hydrograph response. Surprisingly, our detailed analysis showed that surface saturation dynamics were weakly correlated to discharge and precipitation; cumulative rainfall on near-stream saturated areas alone was unable to explain the flow generated within this reach. Streamflow isotopic response was essentially unchanging within the 5-week monitoring period (-55 to -58 δ2D and -8.5 to -9 for δ18O ‰) suggesting that well-mixed streamflow sources that were little affected by rainfall sources. While Na+, Mg2+, and Ca2+ show slight flushing and dilution responses, riparian and streamflow sources responded differently across the event. Overall, groundwater exfiltration within the saturated area appeared to generate streamflow throughout the reach, effectively erasing any rainfall onto saturated area signal.

  16. Integration of semi-automatic detection and sediment connectivity assessment for the characterization of sediment source areas in mountain catchments

    Science.gov (United States)

    Crema, Stefano; Bossi, Giulia; Marchi, Lorenzo; Cavalli, Marco

    2016-04-01

    Identifying areas that are directly delivering sediment to the channel network or to a catchment outlet is of great importance for a sound sediment dynamic characterization and for assessing sediment budget. We present an integration of remote sensing analysis techniques to characterize the effective sediment contributing area that is the sub-portion of the catchment in which sediment is effectively routed towards the catchment outlet. A semi-automatic mapping of active sediment source areas is carried out via image analysis techniques. To this purpose, satellite multispectral images and aerial orthophotos are considered for the analysis. Several algorithms for features extraction are applied and the maps obtained are compared with an expert-based sediment source mapping derived from photointerpretation and field surveys. The image-based analysis is additionally integrated with a topography-driven filtering procedure. Thanks to the availability of High-Resolution, LiDAR-derived Digital Terrain Models, it is possible to work at a fine scale and to compute morphometric parameters (e.g., slope, roughness, curvature) suitable for refining the image analysis. In particular, information on local topography was integrated with the image-based analysis to discriminate between rocky outcrops and sediment sources, thus improving the overall consistency of the procedure. The sediment source areas are then combined with the output of a connectivity assessment. A topography-based index of sediment connectivity is computed for the analyzed areas in order to better estimate the effective sediment contributing area and to obtain a ranking of the source areas in the studied catchments. The study methods have been applied in catchments of the Eastern Italian Alps where a detailed census of sediment source areas is available. The comparison of the results of image analysis with expert-based sediment sources mapping shows a satisfactory agreement between the two approaches

  17. The Management of Mitigation and Reconstruction for the Hazardous Catchment Areas Caused by the 2009 Typhoon Morakot

    OpenAIRE

    Wang, Chin-Lun; Chung, Chi-Rong; Shieh, Chjeng-Lun; Lai, Wen-Chi

    2012-01-01

    Typhoon Morakot accompanied strong southwesterly monsoonal flow brought extreme heavy rain over the southern half region of Taiwan in August 2009. The large extent, high intensity and long duration rainfall caused huge damage. The objectives of this paper are to evaluate the benefit of reconstruction and management for the main disaster catchment areas, to arrange the results of conservation management of the Soil and water Conservation Bureau in sediment-related disaster area and to review a...

  18. Species identification and selection to develop agroforestry at Lake Toba Catchment Area (LTCA

    Directory of Open Access Journals (Sweden)

    NURHENI WIJAYANTO

    2011-01-01

    Full Text Available Wijayanto N (2011 Species identification and selection to develop agroforestry at Lake Toba Catchment Area (LTCA. Biodiversitas 12: 52-58. In order to improve land productivity surrounding the LTCA, the existing ITTO project tries to establish agroforestry system. The system will be designed to meet consideration of both sides. on one side is to generate the people awareness of the forest and land rehabilitation, and on the other side is to support the poverty reduction. The aims of this research are: species identification and selection to develop agroforestry at LTCA. Data collecting was carried out with: interview, group discussion, field observation, divining manual study, and PRA. The diversity of the available crop kind shows the number of choices to be developed by the farmer. The farmers generally have the economic objective to develop agroforestry, including increase in net income, risk reduction, increase in environmental service, and the wealth and savings accumulation. Various types of agricultural crops, plantations and forest trees were found in LTCA. They can be the basis for building a wide variety of agroforestry systems.

  19. Ecological Management of the Mau Catchment Area and it’s Impact on Lake Nakuru National Park.

    OpenAIRE

    Gichuhi, M.

    2013-01-01

    The purpose of this research is to evaluate the impact of human activities in the Mau catchment area and Lake Nakuru National Park. The increase in human population has led to increased pressure and diminishing of natural resources such as forests, grassland and water. This has led to conflicts over these resources. Developments in Nakuru town and other urban centers have contributed to pollution of Lake Nakuru National Park through the disposal of industrial and domestic wa...

  20. CONDITIONS OF FISH FARMING IN NATURA 2000 AREAS, BASED ON THE EXAMPLE OF THE CATCHMENT OF BARYCZ

    OpenAIRE

    Katarzyna Tokarczyk-Dorociak; Andrzej Drabiński; Szymon Szewrański; Sławomir Mazurek; Wanda Kraśniewska

    2016-01-01

    One of the factors that contributed to the construction of approx.77 km2 offish ponds in the catchment of Barycz starting from the 13th century, which in turn transformed the woods into a mosaic of waters, forests and arable land, were the advantageous physiographic conditions. Fish farming operations conducted in this area led to the creation of a cultural landscape characterised by unique natural values, similar to the natural landscape.Approx.240 species of birds are observed here, of whic...

  1. Surface resistance calibration for a hydrological model using evapotranspiration retrieved from remote sensing data in Nahe catchment forest area

    OpenAIRE

    Bie, W.; Casper, M. C.; Reiter, P.; Vohland, M.

    2015-01-01

    In this paper, a method combining graphical and statistical techniques is proposed for surface resistance calibration in a distributed hydrological model, WaSiM-ETH, by comparing daily evapotranspiration simulated by model WaSiM-ETH with corresponding daily evapotranspiration retrieved from remote sensing images. The study area locates in Nahe catchment (Rhineland-Palatinate, Germany, 4065 km2) forest regions. The remote sensing based observations are available for a very limited number of da...

  2. Estimating the prevalence of mental disorders in U.S. adults from the Epidemiologic Catchment Area Survey.

    OpenAIRE

    Bourdon, K H; Rae, D S; Locke, B Z; Narrow, W.E.; Regier, D A

    1992-01-01

    The National Institute of Mental Health Epidemiologic Catchment Area Survey is a comprehensive, community-based survey of mental disorders and use of services by adults, ages 18 and older. Diagnoses are based on the criteria in the "Diagnostic and Statistical Manual of Mental Disorders," third edition, and were obtained in five communities in the United States through lay-interviewer administration of the National Institute of Mental Health Diagnostic Interview Schedule. Results from the surv...

  3. Watershed Modeling with ArcSWAT and SUFI2 In Cisadane Catchment Area: Calibration and Validation of River Flow Prediction

    Directory of Open Access Journals (Sweden)

    Iwan Ridwansyah

    2014-04-01

    Full Text Available Increasing of natural resources utilization as a result of population growth and economic development has caused severe damage on the watershed. The impacts of natural disasters such as floods, landslides and droughts become more frequent. Cisadane Catchment Area is one of 108 priority watershed in Indonesia. SWAT is currently applied world wide and considered as a versatile model that can be used to integrate multiple environmental processes, which support more effective watershed management and the development of better informed policy decision. The objective of this study is to examine the applicability of SWAT model for modeling mountainous catchments, focusing on Cisadane catchment Area in west Java Province, Indonesia. The SWAT model simulation was done for the periods of 2005 – 2010 while it used landuse information in 2009. Methods of Sequential Uncertainty Fitting ver. 2 (SUFI2 and combine with manual calibration were used in this study to calibrate a rainfall-runoff. The Calibration is done on 2007 and the validation on 2009, the R2 and Nash Sutchliffe Efficiency (NSE of the calibration were 0.71 and 0.72 respectively and the validation are 0.708 and 0.7 respectively. The monthly average of surface runoff and total water yield from the simulation were 27.7 mm and 2718.4 mm respectively. This study showed SWAT model can be a potential monitoring tool especially for watersheds in Cisadane Catchment Area or in the tropical regions. The model can be used for another purpose, especially in watershed management.

  4. The potential benefits of herbicide regulation: a cautionary note for the Great Barrier Reef catchment area.

    Science.gov (United States)

    Davis, A M; Lewis, S E; Brodie, J E; Benson, Ash

    2014-08-15

    Industry transitions away from traditional photosystem II inhibiting (PSII) herbicides towards an 'alternative' herbicide suite are now widely advocated as a key component of improved environmental outcomes for Australia's Great Barrier Reef and improved environmental stewardship on the part of the Queensland sugar industry. A systematic desktop risk analysis found that based on current farming practices, traditional PSII herbicides can pose significant environmental risks. Several of the 'alternatives' that can directly fill a specific pre-emergent ('soil residual') weed control function similar to regulated PSII herbicides also, however, presented a similar environmental risk profile, regardless of farming systems and bio-climatic zones being considered. Several alternatives with a pre-emergent residual function as well as alternative post-emergent (contact or 'knockdown') herbicides were, predicted to pose lower environmental risks than the regulated PSII herbicides to most trophic levels, although environmental risks could still be present. While several herbicides may well be viable alternatives in terms of weed control, they can still present equal or possibly higher risks to the environment. Imposing additional regulations (or even de-registrations) on particular herbicides could result in marginal, and possibly perverse environmental impacts in the long term, if usage shifts to alternative herbicides with similar risk profiles. Regardless of any regulatory efforts, improved environmental sustainability outcomes in pesticide practices within the Great Barrier Reef catchment area will hinge primarily on the continuing adoption of integrated, strategic pest management systems and technologies applied to both traditional and 'alternative' herbicides. One of the emerging policy challenges is ensuring the requisite technical and extension support for cane growers to ensure effective adoption of rapidly evolving farming system technologies, in a very dynamic and

  5. Effect of Catchment Area Activities on the Physico – Chemical Characteristics of Water of Upper Lake, Bhopal with Special Reference to Nitrate and Phosphate Concentration

    Directory of Open Access Journals (Sweden)

    Ranjana Talwar

    2014-04-01

    Full Text Available With the tremendous influx of people and consequent urban development, increased anthropogenic activities in the catchment, inflow of untreated sewage, nutrients and pesticides from urban and rural areas, the water quality of Upper Lake, Bhopal has deteriorated significantly. An attempt has been made to study various physico – chemical parameters, specifically nitrates and phosphates of five different sampling sites of Upper Lake and to study the effect of catchment area activities on these sites.

  6. Concentration of radiocesium in stream water from a mountainous catchment area during rainfall events

    International Nuclear Information System (INIS)

    Terrestrial and aquatic systems were contaminated with radioactive materials following the nuclear accident at Fukushima Daiichi Nuclear Power Station on 11 March, 2011. It is important that levels of radiocesium (Cs) in stream water from affected areas be monitored as this water is used for paddy irrigation and domestic water. Additionally, soil particles and organic matter from the streams are deposited in rivers, estuaries and into the ocean. Predictions suggest that Cs levels will increase during intense rainfall-runoff events. To check this prediction, we monitored temporal changes in runoff events and Cs levels in stream water from a mountainous catchment area northwest of the Fukushima plant. In March and April, 2012, the concentrations of Cs and suspended solids (SS) in stream water taken from low-level water flow were found to be 0.2-0.3 Bq/L and 2-7 mg/L, respectively. A heavy rainfall event in July 2012 resulted in an increase and subsequent decrease of both the runoff volume and SS concentration. At the beginning of the rainfall event the concentration of Cs absorbed in the SS was measured to be 23 Bq/L, this decreased gradually to 0.3 Bq/L over the course of the event. The concentration of Cs dissolved in the water was 0.1 Bq/L, this decreased only slightly during the runoff event. During a low rainfall event in September 2012 the concentration of Cs absorbed in the SS at the beginning of the rainfall event was found to be 15 Bq/L, this decreased gradually to 0.5 Bq/L as the amount of SS in the water decreased. The concentration of Cs dissolved in the water was 0.2 Bq/L, again this decreased only slightly over the course of the runoff event. The Cs levels in stream water, during rainfall-runoff events, were primary influenced by the concentration of SS. The amount of Cs dissolved in the water, on the other hand, was roughly constant at 0.1-0.2 Bq/L. The results of this study indicate that, although the concentration of Cs in stream water is below the

  7. Late Pleistocene and Holocene landscape formation in a gully catchment area in Northern Hesse, Germany

    DEFF Research Database (Denmark)

    Döhler, Susanne; Damm, Bodo; Terhorst, Birgit;

    2015-01-01

    , the Holocene landscape development and soil erosion history are investigated using anthropogenic soil sediments and alluvial fan sediments. Until now, a combination of these approaches has not been applied to a gully catchment to this extent. The distribution of the different Quaternary sediments...

  8. Impact of spatial and temporal resolution of rainfall inputs on urban hydrodynamic outputs: A multi-catchment investigation

    DEFF Research Database (Denmark)

    Ochoa-Rodriguez, Susana; Wang, Lipen; Gires, Auguste;

    2015-01-01

    Urban catchments are typically characterised by high spatial variability and fast runoff processes resulting in short response times. Hydrological analysis of such catchments requires high resolution precipitation and catchment information to properly represent catchment response. This study...... investigated the impact of rainfall input resolution on the outputs of detailed hydrodynamic models of seven urban catchments in North-West Europe. The aim was to identify critical rainfall resolutions for urban catchments to properly characterise catchment response. Nine storm events measured by a dual...... for standardising model outputs and making results comparable were implemented. Results were analysed in the light of storm and catchment characteristics. Three main features were observed in the results: (1) the impact of rainfall input resolution decreases rapidly as catchment drainage area increases; (2...

  9. 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

  10. Typology of potential high contribution areas in the sediment budget in the Upper Guil Catchment (Queyras, French Alps)

    Science.gov (United States)

    Lissak, Candide; Fort, Monique; Fassetta, Gilles Arnaud; Viel, Vincent; Carlier, Benoit

    2015-04-01

    In mountainous areas, especially in large river catchments with torrential tributaries, the production and sediment transport significantly increase flood impacts in the valley bottoms. For a better understanding of Alpine river catchments considered as complex systems, we focused our research on the Guil River catchment (Queyras, Southern French Alps - 317km²). This catchment is prone to catastrophic summer floods (June 1957 (> R.I. 100 yr), June 2000 (R.I. 30 yr)...) characterized by considerable sediment transport from tributaries to downvalley, very much facilitated by strong hillslope-channel connectivity (≈12,000 m3 volume of sediment aggraded during the June 2000 flood event). During the last flood events, several infrastructures and buildings were seriously damaged. Most of them were located at confluences and, at specific reaches such as canyon reaches constrained by infrastructures. For risk mitigation some protection equipments were built after the 1957 event, but most of them are now poorly maintained and might be less effective in case of flood event. In the frame of SAMCO (ANR 12 SENV-0004) project designed for mountain hazard mitigation in a context of Climate Change, one objective is to understand the hydro-geomorphological functioning of Alpine catchments for a sustainable management of sediment yield, transfer and deposition. Part of our study is aimed at a better assessment of sediment transfers, especially on adjacent sediment supply (i.e. from hillslope to channel, and from tributaries to the trunk river) for a better management of sediment fluxes in the frame of the local "River Scheme". For this reason, we decided to establish a sediment budget of the Guil River catchment, with a quantitative assessment and a spatial analysis of erosion, transport, and deposition processes. The initial phase of our study consists in identifying contributive, erosion and deposition areas with a twofold approach: (i) assessment of longitudinal sedimentary

  11. THE FIRST PLAN FOR WATER RESOURCES MANAGEMENT OF SOMEȘ-TISA CATCHMENT AREA

    Directory of Open Access Journals (Sweden)

    SOFRONIE C.

    2014-03-01

    Full Text Available With time, after Romania’s accession to the E.U., the national legislation adhered to the Water Framework Directive. In the study we present the Someş and Tisa river catchments management and development plans, from the beginnings till today. We also conclude that the ecological and chemical state for the water bodies in agreement with the Water Framework Directive represents the main challenge for the future of these waters.

  12. THE FIRST PLAN FOR WATER RESOURCES MANAGEMENT OF SOMEȘ-TISA CATCHMENT AREA

    OpenAIRE

    SOFRONIE C.; STOICA F.

    2014-01-01

    With time, after Romania’s accession to the E.U., the national legislation adhered to the Water Framework Directive. In the study we present the Someş and Tisa river catchments management and development plans, from the beginnings till today. We also conclude that the ecological and chemical state for the water bodies in agreement with the Water Framework Directive represents the main challenge for the future of these waters.

  13. Developing a geological 3D model for the Tanour and Rasoun spring catchment area using ArcGIS and GOCAD

    Science.gov (United States)

    Hamdan, Ibraheem; Benhsinat, Mohamed; Wagner, Bianca; Sauter, Martin

    2016-04-01

    Key words: Karst, 3D model, GOCAD, ArcGIS, Jordan. Tanour and Rasoun karst springs (around 75 km northwest of the capital city of Amman in Jordan) are used as main local water supply for the surrounding villages. Carbonate rocks are the predominant rock type in the study area (Upper Cretaceous age). The karstification degree is moderate to high, with the availability of different karst features like dolines, caves, dry valleys, and highly fractured rocks. During the last years, the water supply from these springs had to be disconnected for several times due to microbial contamination and waste water pollution from local olive oil mills. For better understanding of the geological and the hydrogeological setting of the study area, in addition to the delineation of the groundwater catchment area for Tanour and Rasoun springs, a geological 3D model of the main geological formations within the study area was established using ArcGIS and GOCAD. The model is based on geological maps and well data; it was established for seven geological layers that act as prominent aquifers and aquicludes. ArcGIS software was used for data preparation, processing and interpolation of varying thickness, while GOCAD used for geometrical modeling steps. After the completion of the first modeling steps, major faults are included. Then the subsurface catchments will be delineated and compared with the superficial watersheds. The model still under development and open for further development.

  14. Minimising costs of environmental service provision: water-yield, salt-load and biodiversity targets with new tree planting in Simmons Creek Catchment, NSW, a dryland farming/grazing area.

    OpenAIRE

    Nordblom, Thomas L.; Hume, Iain H.; Cresswell, Hamish; Glover, Mark; Hean, Robyn L.; Finlayson, John D.; Wang, Enli

    2007-01-01

    Although dryland farming and grazing have been practiced for over 130 years in the 17,000 ha Simmons Creek catchment without surface salinity problems, the area has been identified as a significant source of salt seepage to Billabong Creek in the NSW Murray catchment. Groundwater movement and salinity levels are spatially heterogenous at Simmons Creek. Groundwater of the upper catchment is relatively fresh and seemingly unconnected with the highly saline groundwater of the lower catchment. Ho...

  15. Eco-physiological Study on the Influence of Contaminated Waters from the Topolnitza River Catchment Area on Some Crops

    Directory of Open Access Journals (Sweden)

    Iliana Velcheva

    2012-12-01

    Full Text Available The present study is a small part of a program for an investigation of the water conditions in the Topolnitza Dam Lake, Topolnitza River and its catchment area. The sensitivity of seeds and young wheat, sunflower and mustard plants to heavy metal stress was examined at laboratory conditions. Our results showed that seedling growth was more sensitive to heavy metals in comparison to seed germination. The length of shoot and root has been adversely affected due to water contamination when compared to the control. A certain negative effect on the photosynthetic pigments content was registered.

  16. Integration of remote sensing and GIS in monitoring the dynamics of land cover in Oroba-Kibos catchment area, Kenya

    Institute of Scientific and Technical Information of China (English)

    Were KO; Owenga PO; Wagate PN; Orlale R

    2011-01-01

    Land cover in Kenya is in a state of flux at different spatial and temporal scales.This compromises environmental integrity and socioeconomic stability of the population hence increasing their vulnerability to the externalities of environmental change.The Oroba-Kibos catchment area in western Kenya is one locality where rapid land use changes have taken place over the last 30 years.The shrubs,swamps,natural forests and other critical ecosystems have been converted on the altar of agriculture,human settlement,fuel wood and timber.This paper presents the results ora study that aimed at providing spatially-explicit information for effective remedial response through (a) Mapping the land cover; (b) Identifying the spatial distribution of land cover changes; (c) Determining the nature,rates and magnitude of the land cover changes,and; (d) Establishing the drivers of land use leading to land cover changes in Oroba-Kibos catchment area.Bi-temporal Landsat TM imagery,field observation,household survey and ancillary data were obtained.Per-field classification of the Landsat TM imagery was performed in a GIS and the resultant land cover maps assessed using the field observation data.Post-classification comparison of the maps was then done to detect changes in land cover that had occurred between 1994 and 2008.SPSS was used to analyze the household survey data and attribute the detected land cover changes to their causes.The findings showed that 9 broad classes characterize the catchment area including the natural forests,swamps,natural water bodies,woodlands,shrublands,built-up lands,grasslands,bare lands and croplands.Croplands are dominant and accounted for about 65% (57122 ha) of the total land in 1994,which increased at the rate of 0.89% to 73% (64772 ha) in 2008,while natural water bodies has the least spatial coverage accounting for about 0.6% (561 ha) of the total land in 1994,which diminished at the rate of 3.57% to 0.3% (260 ha) in 2008.Climate,altitude,access and

  17. The inflow of 238Pu and 239+240Pu from the Vistula River catchment area to the Baltic Sea

    International Nuclear Information System (INIS)

    The aim of the work was to estimate plutonium inflow from the Vistula River's catchments area to the Baltic Sea. There were differences in plutonium activities depending on season and sampling site. The highest activities of 238Pu and 239+240Pu were transported from the Vistula River watershed to the Baltic Sea in spring and the lowest in summer. Annually, the southern Baltic Sea is enriched via the Vistula River with 10.3 MBq of 238Pu and 89.0 MBq of 239+240Pu. The enhanced concentration of plutonium in water from the Vistula River is the result of its runoff from the Vistula drainage area, mostly from snowmelt, enhanced rainfalls and leached materials from river bed. - Highlights: → We estimated plutonium inflow from the Vistula River catchment area to the Baltic Sea. → We found differences in Pu activities depending on season and sampling site. → The highest amount of 239 + 240Pu was transported in spring and the lowest in summer. → Annually, the southern Baltic Sea is enriched with 89.0 MBq of 239 + 240Pu. → Enhanced Pu amount in water came from snowmelt, rainfalls and leached materials.

  18. Identifying critical source areas for water quality: 1. Mapping and validating transport areas in three headwater catchments in Otago, New Zealand

    Science.gov (United States)

    Srinivasan, M. S.; McDowell, R. W.

    2009-12-01

    SummaryValidity of five empirical to process-based, hydrological models described by Srinivasan and McDowell (2007) in mapping transport areas was tested in the Invermay and Glenomaru headwater catchments in Otago, New Zealand. These transport areas together with contaminant source areas form critical source areas (CSAs), where the majority of contaminant loss occurs and therefore represent areas where mitigation potential would be most efficient. Rainfall and 15-min instantaneous surface flows at the catchment outlets and the shallow water table (animal tracks. During wet periods (above-average rainfall), flow from these areas accounted for 10-70% of total stormflows. Water table data indicated that saturated areas with the water table at the surface rarely extended >10 m from the stream during storm events. There appeared to be an active subsurface (shallow) flow system transferring flows from land to streams. However, during many rainfall events, semi-pervious areas like fence lines, animal tracks and gateways were connected to the stream via infiltration-excess surface runoff, as measured by surface runoff samplers. This may be a significant for contaminant transfer given the amount of time spent by animals on these areas and deposition of contaminants (e.g., in dung) and is explored in a companion paper. Of the approaches used to delineate transport areas during storms, generally the empirically-based curve number model and Phosphorus Index over-predicted stormflow areas. The drainage density approach predicted stormflow areas well, but under-predicted flow volumes by 55-82%. The physically-based topographic index (TI) model and a model combining TI model and surface runoff from semi-pervious areas predicted flow volumes within 6% of that observed, but the extent of predicted transport areas greatly differed from those observed. Among the five approaches, the process-based approaches were identified to be more applicable and expandable for future prediction of

  19. Organochlorine pesticides (OCPs) in the Indus River catchment area, Pakistan: Status, soil-air exchange and black carbon mediated distribution.

    Science.gov (United States)

    Bajwa, Anam; Ali, Usman; Mahmood, Adeel; Chaudhry, Muhammad Jamshed Iqbal; Syed, Jabir Hussain; Li, Jun; Zhang, Gan; Jones, Kevin C; Malik, Riffat Naseem

    2016-06-01

    Organochlorine pesticides (OCPs) were investigated in passive air and soil samples from the catchment area of the Indus River, Pakistan. ∑15OCPs ranged between 0.68 and 13.47 ng g(-1) in soil and 375.1-1975 pg m-(3) in air. HCHs and DDTs were more prevalent in soil and air compartments. Composition profile indicated that β-HCH and p,p'-DDE were the dominant of all metabolites among HCHs and DDTs respectively. Moreover, fBC and fTOC were assessed and evaluated their potential role in the distribution status of OCPs. The fTOC and fBC ranged between 0.77 and 2.43 and 0.04-0.30% respectively in soil. Regression analysis showed the strong influence of fBC than fTOC on the distribution of OCPs in the Indus River catchment area soil. Equilibrium status was observed for β-HCH, δ-HCH, p,p'-DDD, o,p'-DDT, TC, HCB and Heptachlor with ff ranged between 0.3 and 0.59 while assessing the soil-air exchange of OCPs. PMID:26978705

  20. Groundwater Impacts on Urban Surface Water Quality in the Lowland Polder Catchments of the Amsterdam City Area

    Science.gov (United States)

    Rozemeijer, J.; Yu, L.; Van Breukelen, B. M.; Broers, H. P.

    2015-12-01

    Surface water quality in the Amsterdam area is suffering from high nutrient levels. The sources and transport mechanisms of these nutrients are unclear due to the complex hydrology of the highly manipulated urban and sub-urban polder catchments. This study aimed at identifying the impact of groundwater on surface water quality in the polder catchments of the greater Amsterdam city area. Therefore, we exploited the dense groundwater and surface water monitoring networks to explain spatial patterns in surface water chemistry and their relations with landscape characteristics and groundwater impact. We selected and statistically analyzed 23 variables for 144 polders, covering a total area of 700 km2. Our dataset includes concentrations of total-N, total-P, ammonium, nitrate, bicarbonate, sulfate, calcium, and chloride in surface water and groundwater, seepage rate, elevation, paved area percentage, surface water area percentage, and soil type (calcite, humus and clay percentages). Our results show that nutrient levels in groundwater were generally much higher than in surface water and often exceeded the surface water Environmental Quality Standards (EQSs). This indicates that groundwater is a large potential source of nutrients in surface water. High correlations (R2 up to 0.88) between solutes in both water compartments and close similarities in their spatial patterns confirmed the large impact of groundwater on surface water quality. Groundwater appeared to be a major source of chloride, bicarbonate and calcium in surface water and for N and P, leading to exceeding of EQSs in surface waters. In dry periods, the artificial redistribution of excess seepage water from deep polders to supply water to infiltrating polders further distributes the N and P loads delivered by groundwater over the area.

  1. Analysis of anthropogenic impacts on the hydrological state of a Pleistocene catchment area using remote sensing techniques

    Science.gov (United States)

    Leuschner, Annette; Merz, Christoph; Steidl, Jörg; van Gasselt, Stephan

    2016-04-01

    The water budget of a catchment area can be depicted by the complex interaction between topography and discharge as well as anthropogenic and climatic impacts. Over the last decades, the Pleistocene lowlands of North-Eastern Germany have experienced extensive anthropogenic modifications. The hydrological system has been significantly altered by the installation of artificial drainage, such as surface ditches and subsurface tile drains. It has been shown, that artificial drainage systems provide pathways for diffuse nutrients and pollutants leaching into surface and also subsurface water bodies, which is especially pronounced in lowland areas. The detection of these transport paths is important for obtaining an understanding of the regional water and substance balance and the development of strategies to improve hydrological conditions. Unfortunately, detailed data about locations of historic artificial drainage are rare or not available at all. The aim of this study was to identify the extensive anthropogenic modifications, like artificial drainage networks and land use changes, over the last decades with the aid of photogrammetric data and multispectral imagery. The detection of anthropogenic modifications is based on the method of Tetzlaff, et al. (2009), who developed an approach by interpreting aerial photographs for drained areas. We used color-infrared (CIR) aerial photographs, in order to apply different spectral techniques for obtaining information about water content and vitality status of plant cover. Although this method is sensitive to daily variations of soil moisture and plant growth as response to climate conditions, and the type of drainage pipe installation technique, we were able to identify different locations of artificial drainage. Complementary to this approach we utilized spectral classification methods for land cover in order to extract different land cover categories, and evaporation rates, depending on the land cover and surface

  2. Measuring Spatial Accessibility of Health Care Providers – Introduction of a Variable Distance Decay Function within the Floating Catchment Area (FCA) Method

    Science.gov (United States)

    Groneberg, David A.

    2016-01-01

    We integrated recent improvements within the floating catchment area (FCA) method family into an integrated ‘iFCA`method. Within this method we focused on the distance decay function and its parameter. So far only distance decay functions with constant parameters have been applied. Therefore, we developed a variable distance decay function to be used within the FCA method. We were able to replace the impedance coefficient β by readily available distribution parameter (i.e. median and standard deviation (SD)) within a logistic based distance decay function. Hence, the function is shaped individually for every single population location by the median and SD of all population-to-provider distances within a global catchment size. Theoretical application of the variable distance decay function showed conceptually sound results. Furthermore, the existence of effective variable catchment sizes defined by the asymptotic approach to zero of the distance decay function was revealed, satisfying the need for variable catchment sizes. The application of the iFCA method within an urban case study in Berlin (Germany) confirmed the theoretical fit of the suggested method. In summary, we introduced for the first time, a variable distance decay function within an integrated FCA method. This function accounts for individual travel behaviors determined by the distribution of providers. Additionally, the function inherits effective variable catchment sizes and therefore obviates the need for determining variable catchment sizes separately. PMID:27391649

  3. [Specific Features of Radioactive Pollution of Soils of Catchment Areas of Lake Shablish (Distant Zone of the East Ural Radioactive Trace)].

    Science.gov (United States)

    Deryagin, V V; Levina, S G; Sutyagin, A A; Parfilova, N S

    2015-01-01

    Specific features of 90Sr and 137Cs distribution and accumulation in soil cuts of superaqueous and eluvial positions of catchment areas of Lake Shablish located in a distant zone of the East Ural radioactive trace are considered. Some physical and chemical characteristics of the soils were defined. It is established that the signs typical for the lake ecosystems of distant East-Ural radioactive trace zone which underwent impact of technogenic influence are common for soils of catchment areas of Lake Shablish. The distinctions in some characteristic features of the specific activity of long-living radionuclides for the soils of superaqueous and eluvial positions of catchment areas connected with the character of the water regime of soils are shown.

  4. Occurrence of Antibiotics in Surface and Groundwater of a Drinking Water Catchment Area in Germany.

    Science.gov (United States)

    Burke, Victoria; Richter, Doreen; Greskowiak, Janek; Mehrtens, Anne; Schulz, Lena; Massmann, Gudrun

    2016-07-01

    The contamination of the aquatic environment with organic micropollutants, such as veterinary pharmaceuticals, has become an increasingly serious problem and has aroused attention in the course of the last decades. This study presents a screening for a series of veterinary antibiotics, potentially introduced by the application of liquid manure, in ground- and surface water of a drinking water catchment in Lower Saxony, Germany. Of the 26 compounds analyzed, eight, including sulfadiazine, sulfapyridine, sulfamethoxazole, trimethoprim, dehydrato-erythromycin, sulfadimidine, tylosin, and tetracycline were detected in surface water samples. Trimethoprim was detected in 11 out of 15 shallow groundwater samples, indicating its high environmental relevance. Column sorption experiments conducted on trimethoprim show a comparatively moderate sorption affinity to sandy aquifer material with a retardation coefficient of 5.7. PMID:27329061

  5. Sylvicultural procedures in catchment areas of the mountain streams as exemplified by the Skrzyczne massif in Poland

    Directory of Open Access Journals (Sweden)

    Małek Stanisław

    2014-03-01

    Full Text Available Extensive disintegration of spruce forests in the Beskidy Mts. in South Poland generates a need to regenerate sizeable areas as well as to rebuild forest stands which have defended themselves against breakdown. In practice, the magnitude of relevant management tasks does not allow for keeping up with the progressive destruction of forest, especially at higher altitudes, where natural regeneration does not occur as much as necessary. In addition, the species composition is limited to spruce, sometimes accompanied by beech and fir, whereas other species have a negligible share. What may be helpful in solving this problem is the method of regeneration of such areas and of establishment of under-canopy cultures, consisting of patchwork, multi-stage regeneration task performance, starting from the areas with the best chance of reforestation success and using the existing self-sown trees. Such areas undoubtedly include habitats with better water balance, i.e. humid habitats (in the case of larger areas, distinguished in the forest management plan as humid forest site types. The aim of the present study was to propose management of watercourses and headwater areas in the region of the Skrzyczne massif where the selected catchments are situated on the southern (the Malinowski Stream and the northern (the Roztoka Czyrna stream slopes of this massif. The research was carried out in August 2012 and included juxtaposition of available hydrological maps with actual field conditions along with identification of springs and streams and the course of their beds in order to update the existing data. The updating of the forest numerical maps in the existing databases of the State Forests IT System (SILP included verification of the course of streams and determination of their nature (permanent or periodic with a division into the existing ones and the added ones. The data was recorded against the background of the division of the forest surface, contour lines

  6. Assessment of river water quality during snowmelt and base flow periods in two catchment areas with different land use.

    Science.gov (United States)

    Woli, Krishna Prasad; Hayakawa, Atsushi; Kuramochi, Kanta; Hatano, Ryusuke

    2008-02-01

    River water quality was evaluated with respect to eutrophication and land use during spring snowmelt and summer base flow periods in Abashiri (mixed cropland-livestock farming) and Okoppe (grassland-based dairy cattle farming), eastern Hokkaido, Japan. Water from rivers and tributaries was sampled during snowmelt and summer base flow periods in 2005, and river flow was measured. Total N (TN), NO(3)-N, and Si concentrations were determined using standard methods. Total catchment and upland areas for each sampling site were determined with ArcGIS hydrology modeling software and 1:25,000-scale digital topographic maps. Specific discharge was significantly higher during snowmelt than during base flow. In both areas, TN concentrations increased, whereas Si concentrations decreased, with increased specific discharge, and were significantly higher during snowmelt. The Si:TN mole ratio decreased to below or close to the threshold value for eutrophication (2.7) in one-third of sites during snowmelt. River NO(3)-N concentrations during base flow were significantly and positively correlated with the proportion of upland fields in the catchment in both the Abashiri (r = 0.88, P slope, defined as the impact factor (IF) of water quality, was much higher in Abashiri (0.025) than in Okoppe (0.0094). The correlations were also significantly positive during snowmelt in both areas, but IF was four to eight times higher during snowmelt than during base flow. Higher discharge of N from upland fields and grasslands during snowmelt and the resulting eutrophication in estuaries suggest that nutrient discharge during snowmelt should be taken into account when assessing and monitoring the annual loss of nutrients from agricultural fields. PMID:17503203

  7. Ethnicity, Education, and the Temporal Stability of Personality Traits In the East Baltimore Epidemiologic Catchment Area Study

    Science.gov (United States)

    Löckenhoff, Corinna E.; Terracciano, Antonio; Bienvenu, O. Joseph; Patriciu, Nicholas S.; Nestadt, Gerald; McCrae, Robert R.; Eaton, William W.; Costa, Paul T.

    2008-01-01

    We examined the influence of age, gender, Black vs. White ethnicity, and education on five indices of personality stability and change across an average interval of 8 years in the East Baltimore Epidemiologic Catchment Area study. In the full sample (n = 505, aged 30-88), examination of structural, rank-order, ipsative, and mean level stability, as well as indices of reliable change suggested that NEO-PI-R personality traits showed moderate to high levels of stability over time. There were few age and gender effects on temporal stability but rank-order, ipsative, and mean level stability were lower among Blacks and individuals with lower education. Future research should explore additional demographic predictors of temporal plasticity in a diverse range of samples, and employ observer ratings to assess personality. PMID:19122849

  8. Managing the drinking water catchment areas: the French agricultural cooperatives feed back.

    Science.gov (United States)

    Charrière, Séverine; Aumond, Claire

    2016-06-01

    The quality of raw water is problematic in France, largely polluted by nitrates and pesticides (Mueller and Helsel, Nutrients in the nation's waters-too much of a good thing? Geological Survey (U.S.), 1996; European Environment Agency, European waters-assessment of status and pressures, 2012).This type of pollution, even though not always due to agriculture (example of the catchment of Ambleville, county 95, France where the nitrate pollution is mainly due to sewers (2012)), has been largely related to the agricultural practices (Sci Total Environ 407:6034-6043, 2009).Taking note of this observation, and instead of letting it paralyze their actions, the agricultural cooperatives decided with Agrosolutions to act directly on the field with their subscribers to change the agricultural practices impacting the water and the environment.This article shows how the French agricultural cooperatives transformed the awareness of the raw water quality problem into an opportunity for the development and implementation of more precise and responsible practices, to protect their environment. They measure in order to pilot, co-construct and build the best action plans possible according to the three pillars of environment, economy and agronomy.

  9. Managing the drinking water catchment areas: the French agricultural cooperatives feed back.

    Science.gov (United States)

    Charrière, Séverine; Aumond, Claire

    2016-06-01

    The quality of raw water is problematic in France, largely polluted by nitrates and pesticides (Mueller and Helsel, Nutrients in the nation's waters-too much of a good thing? Geological Survey (U.S.), 1996; European Environment Agency, European waters-assessment of status and pressures, 2012).This type of pollution, even though not always due to agriculture (example of the catchment of Ambleville, county 95, France where the nitrate pollution is mainly due to sewers (2012)), has been largely related to the agricultural practices (Sci Total Environ 407:6034-6043, 2009).Taking note of this observation, and instead of letting it paralyze their actions, the agricultural cooperatives decided with Agrosolutions to act directly on the field with their subscribers to change the agricultural practices impacting the water and the environment.This article shows how the French agricultural cooperatives transformed the awareness of the raw water quality problem into an opportunity for the development and implementation of more precise and responsible practices, to protect their environment. They measure in order to pilot, co-construct and build the best action plans possible according to the three pillars of environment, economy and agronomy. PMID:27074925

  10. CONDITIONS OF FISH FARMING IN NATURA 2000 AREAS, BASED ON THE EXAMPLE OF THE CATCHMENT OF BARYCZ

    Directory of Open Access Journals (Sweden)

    Katarzyna Tokarczyk-Dorociak

    2016-07-01

    Full Text Available One of the factors that contributed to the construction of approx.77 km2 offish ponds in the catchment of Barycz starting from the 13th century, which in turn transformed the woods into a mosaic of waters, forests and arable land, were the advantageous physiographic conditions. Fish farming operations conducted in this area led to the creation of a cultural landscape characterised by unique natural values, similar to the natural landscape.Approx.240 species of birds are observed here, of which 170 are nesting species. Due to its natural values, this area has been subject to natural reserve protection as part of the Landscape Park "Dolina Baryczy" (the Barycz Valley. It was entered in the "Living Lakes" list and it is protected under the Ramsar Convention as well as under the European nature protection network Natura 2000.The established forms of nature protection mean the introduction of a certain binding regime, pursuant to which the economic activity conducted in protected areas must take into account the prohibitions and orders introduced by documents that establish the said forms of protection. Additionally, there is a legal requirement to create a protection plan or conservation plan that constitutes a basis for the realisation of conservation-related objectives. A commercial company Stawy Milickie S.A. (public limited company operates in the area of this largest fish pond complex in Poland. The scope of its operations includes more than just the breeding and sale of freshwater fish (6500 ha of ponds but also environmental protection, environmental education and the development of tourism as well as stimulating the development and professional activation of local communities basing on the natural resources that exist in the catchment of Barycz. This study presents the conditions related to fish farming operations conducted in this area. Conducting an extensive management (i.e. often uneconomical from the economic point of view is a

  11. The Analysis of Land Use Based on CORINE Land Cover in the Romanian Part of the Tisa Catchment Area

    Directory of Open Access Journals (Sweden)

    CIPRIAN MOLDOVAN

    2010-01-01

    Full Text Available The analysis of the land use structure of the 13 counties of the Romanian part of Tisa catchment area has been made according to the 2000 edition of CORINE Land Cover, while the 1990 edition has been used for comparative purposes. Out of the total area of 8,269,229.48 hectares, the forests cover 37.92%, the arable lands 35.02% and the grasslands 17.97%. The other types of land use have lower weights, such as the continuous and discontinuous urban fabric 4.81%, the orchards 1.10% and the vineyards 0.98%. In the category of forests, the following types of land use are included: broad-leaved forests, which form the majority (24.72%, coniferous forests (6.22%, mixed forests (3.46% and transitional woodland-shrub areas (3.52%. The forests are mainly located in the Carpathians and the hills. The non-irrigated arable lands (23.50% are predominant within the arable lands. They lie mostly in the Western Plain and in the basins and corridors of the Transylvanian Depression and the Western Hills. The analysis of the dynamics of the land use structure between 1990 and 2000 indicates a relative stability in the case of forests, a decrease of arable lands and an increase of grasslands.

  12. Modelling the spatial distribution of snow water equivalent at the catchment scale taking into account changes in snow covered area

    Directory of Open Access Journals (Sweden)

    T. Skaugen

    2011-12-01

    Full Text Available A successful modelling of the snow reservoir is necessary for water resources assessments and the mitigation of spring flood hazards. A good estimate of the spatial probability density function (PDF of snow water equivalent (SWE is important for obtaining estimates of the snow reservoir, but also for modelling the changes in snow covered area (SCA, which is crucial for the runoff dynamics in spring. In a previous paper the PDF of SWE was modelled as a sum of temporally correlated gamma distributed variables. This methodology was constrained to estimate the PDF of SWE for snow covered areas only. In order to model the PDF of SWE for a catchment, we need to take into account the change in snow coverage and provide the spatial moments of SWE for both snow covered areas and for the catchment as a whole. The spatial PDF of accumulated SWE is, also in this study, modelled as a sum of correlated gamma distributed variables. After accumulation and melting events the changes in the spatial moments are weighted by changes in SCA. The spatial variance of accumulated SWE is, after both accumulation- and melting events, evaluated by use of the covariance matrix. For accumulation events there are only positive elements in the covariance matrix, whereas for melting events, there are both positive and negative elements. The negative elements dictate that the correlation between melt and SWE is negative. The negative contributions become dominant only after some time into the melting season so at the onset of the melting season, the spatial variance thus continues to increase, for later to decrease. This behaviour is consistent with observations and called the "hysteretic" effect by some authors. The parameters for the snow distribution model can be estimated from observed historical precipitation data which reduces by one the number of parameters to be calibrated in a hydrological model. Results from the model are in good agreement with observed spatial moments

  13. Biological and chemical determination of dioxin-like compounds in sediments by means of a sediment triad approach in the catchment area of the river Neckar.

    Science.gov (United States)

    Hollert, Ner; Dürr, Matthias; Olsman, Helena; Halldin, Krister; van Bavel, E; Brack, Werner; Tysklind, Mats; Engwall, Magnus; Braunbeck, Thomas

    2002-10-01

    To evaluate the sediment quality of selected sites in the catchment area of the River Neckar, an integrative assessment approach was used to assess the ecological hazard potential of dioxin-like sediment compounds. The approach is based on 7-ethoxyresorufin-O-deethylase (EROD) induction in embryonic chicken liver culture and comprehensive chemical analyses of polycyclic aromatic hydrocarbons (priority PAHs according to the US Environmental Protection Agency). The majority of the sediment extracts exhibited high potencies as EROD-inducers. In one sediment sample, which was influenced by a sewage treatment plant, a very high concentration of 930 ng bioassay 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) equivalents (bio-TEQs )/g organic carbon could be determined. However, in none of the samples, more than 6% of the EROD-inducing potency could be explained by the PAHs analyzed chemically. Thus, non-analyzed compounds with EROD-inducing potency were present in the extracts. A fractionation of sediment samples according to pH allowed to localize the major part of EROD-inducing compounds in the neutral fractions. However, a significant portion of the EROD induction could also be explained by the acidic fractions. Following the concept of the Sediment Quality Triad according to Chapman, in situ alterations of macrozoobenthos were examined. A comparison of the results predicted by the EROD assay and chemical analyses with alterations in situ, as measured by means of the saprobic index and the ecotoxicological index according to Carmargo, revealed a high ecological relevance of the results of bioassays and chemical analyses for major sites. PMID:12463678

  14. The definition analyses of radiation temperature measurement area

    Institute of Scientific and Technical Information of China (English)

    Fu Tairan; Cheng Xiaofang; Zhong Maohua

    2008-01-01

    In the research of primary spectrum pyrometry, this paper discussed the definition problem of radiation tem-perature measurement area based on the measurement coordinates. For the linear spectrum emissivity model and im-proved monotonic spectrum emissivity model, the characteristics of radiation temperature measurement area restricted by the measurement coordinates were theoretically analyzed, through the investigations of the temperature and emissivity co-ordinate axes. Choosing the specific primary spectrum pyrometer as an example in applications, the theoretical area of radiation temperature measurement of this pyrometer was given and it was verified through blackbody experiments. The discussions of this paper will provide the necessary foundation for the theory research development of primary spectrum pyrometry and the realization of technical applications.

  15. Projected Change in Climate Under A2 Scenario in Dal Lake Catchment Area of Srinagar City in Jammu and Kashmir

    Directory of Open Access Journals (Sweden)

    Saqib Parvaze1,

    2016-08-01

    Full Text Available The present study was done to study the effect of climate change on weather parameters like highest possible temperature, lowest possible temperature, average temperature and precipitation. Multiple linear Regression (MLR, Artificial Neural Network (ANN and Statistical Downscaling Model (SDSM models were tested in the Dal lake catchment area of Jammu and Kashmir State. Twenty seven year weather data (1985-2012 obtained from SKUAST-Kashmir weather station was used for the study. The modeling results showed a first-rate agreement between the observed data and predicted values for temperature series with high coefficient of determination R2 values varying from (0.87-0.97 for different models. In case of precipitation R2 values varied from (0.112-219 for different models. The low values of coefficient of determination in precipitation time series are due to lot of uncertainty in occurrence of precipitation which could not be defined by the selected models. The SDSM showed the best results of the three models tested for prediction of weather parameters. Thus SDSM was used for climate scenario generation. By comparing daily precipitation and temperature series for 1985-2012 with 2015-2030, an overall increasing pattern of 0.46%, 1.96%, 0.95% and 2.66% was observed for monthly, highest possible temperature, lowest possible temperature, average temperature and precipitation.

  16. Surface resistance calibration for a hydrological model using evapotranspiration retrieved from remote sensing data in Nahe catchment forest area

    Science.gov (United States)

    Bie, W.; Casper, M. C.; Reiter, P.; Vohland, M.

    2015-05-01

    In this paper, a method combining graphical and statistical techniques is proposed for surface resistance calibration in a distributed hydrological model, WaSiM-ETH, by comparing daily evapotranspiration simulated by model WaSiM-ETH with corresponding daily evapotranspiration retrieved from remote sensing images. The study area locates in Nahe catchment (Rhineland-Palatinate, Germany, 4065 km2) forest regions. The remote sensing based observations are available for a very limited number of days but representative for most soil moisture conditions. By setting canopy resistance (rc) at 150 s/m, soil surface resistance (rse) at 250 s/m or at 300 s/m for deciduous forest and setting rc at 300 s/m, rse at 600 s/m or at 650 s/m for pine forest, the model exhibits its best overall performance in space and time. It is also found that with sufficient soil moisture, the model exhibits its best performance in space scale.

  17. Nitrates, Heavy Metals and Herbicides in Soil and Waters of Karašica-Vučica Catchment Area

    Directory of Open Access Journals (Sweden)

    Željko Vidaček

    1999-06-01

    Full Text Available Two-years investigations of nitrates, heavy metals and herbicides in soil, surface and groundwater were conducted on agroecological station Kapelna near Donji Miholjac, in the catchment area Karašica - Vučica. Concerning the scientific project "Protection of soil and water in the agriculture" the intensive and extensive land use and fertilization respectively, the trial was organized on amphigley hidroameliorated by channels with and without pipe drainage. Crops in trial were corn (1997. and winter wheat (1997/98. on which were applied two rates of nitrogen fertilizing - extensive and intensive. Determined concentrations of nitrates in soil varied from 0,56 to 5,06 mg NO3-/100 g of soil, and they were regularly higher on variants with intensive fertilizing. Concentrations of nitrates in surface and groundwater sometimes were above maximum allowed concentrations (MAC for all categories of waters, with maximum value 126,0 mg NO3-/l. Content of heavy metals in soil did not aceed MAC for arable soil with heavier texture, while concentrations of copper and cadmium in surface and groundwater were occasionally above MAC for I and II categorie of waters, and lead above MAC for III and IV categories of waters. Maximum content of atrazine in soil was 26 ng/g, and for clortoluron 41,35ng/g. Concentrations of atrazine and clortoluron in surface and groundwater occasionally were above MAC for single and total pesticides in waters, varying from 40 to 1250 ng/l.

  18. Detection and analyse of hazardous roads in rural areas

    DEFF Research Database (Denmark)

    Sørensen, Michael

    2003-01-01

    For the last period of 5-10 years the notion "Grey roads" (hazardous roads) has appeared in Danish traffic safety work and improvement of these roads has become a very important part of the traffic safety work in many countries. The problem is, that the notion never has been clearly defined......, and therefore there are no unambiguos methods to point out and analyse "Grey roads". In this article based on a ph.D.-project a method to detecting "Grey roads" is introduced....

  19. THE MONITORING OF SURFACE WATER BODIES (RIVERS) FROM TISA CATCHMENT AREA - MARAMUREŞ COUNTY IN 2014

    OpenAIRE

    GABRIELA ANDREEA DESPESCU; S. NACU; BĂTINAŞ R

    2016-01-01

    This study is focused on the monitoring and evaluation of river’s water bodies from Maramureş County, using the methodology associated with the EU Water Framework Directive 60/2000. Thus, in the first part are defined the theoretical terms of monitoring activities related to the water bodies’ quality and the specific features of those we can find in the studied area. There are presented the water bodies’ features, quality indicators and the monitoring frequencies for the rivers situated in th...

  20. Roads as sources of heavy metals in urban areas. The Covões Catchment experiment, Coimbra, Portugal

    Science.gov (United States)

    Ferreira, António J. D.; Soares, Daniel; Ferreira, Carla S. S.; Walsh, Rory P. D.

    2015-04-01

    Cities are the home to 50% of the human specie [UN 2011 Ramalho & Hobbs 2012], whose wellbeing, way of life and exposure to hazard situations are directly related to the built environment. Cities are often seen as ecological systems just a short step away from collapse [Newman 2006]. Being a human construction, cities disrupt the natural cycles and the patterns of temporal and spatial distribution of environmental and ecological processes. Urbanization produces ruptures in biota, water, energy and nutrients connectivity that can lead to an enhanced exposure to disruptive events that hamper the wellbeing and the resilience of urban communities in a global change context. A major issue in what concerns the threats to human and ecosystem health in urban areas is the presence of heavy metals, and the related processes that govern their source, transport and fade r uptake by the vegetation. In this work, we present an analysis of heavy metal sources and transport processes at various types of roads within the Ribeira dos Covões peri-urban experimental catchment in central Portugal. The surveyed heavy metals (Cadmium, Lead, Coper, and Zinc) show significant differences as a result of the type of rainfall event, the length of the antecedent dry spell, the traffic volume and the heavy metals sources. For some locations, namely for the roads with heavy traffic volume, the heavy metal concentrations exceed the limits established by law, which has severe implications to the downstream ecosystems and to the possible use of the water from roads to close the resources loop in urban areas, namely in what concerns their use to water the urban green infrastructure or to irrigate the urban agriculture fields.

  1. Inflow of 210Po from the Odra River Catchment Area to the Baltic Sea

    International Nuclear Information System (INIS)

    In this study the activity of polonium 210Po in the Odra River water samples, collected from October 2003 to July 2004 has been was determined using alpha spectrometry. In autumn the highest concentration of 210Po was found in the Odra River water at Gozdowice (1.64 ± 0.08 Bq m-3) and in the Nysa Luzycka River (5.21 ± 0.19 Bq m-3). In contrary, the lowest concentrations were determined in water from the Barycz and the Bystrzyca Rivers (1.09 ± 0.07 and 1.09 ± 0.06 Bq m-3, respectively). During winter season, in turn, the highest concentration of 210Po was observed in the Odra River water collected at Chalupki (3.64 ± 0.03 Bq m-3) and Slubice (3.62 ± 0.03 Bq m-3), and the lowest in the Notec River (1.00 ± 0.06 Bq dm-3). In spring the highest concentration was in the Odra at Slubice (3.32 ± 0.04 Bq m-3) and in the Nysa Klodzka River (4.04 ± 0.03 Bq m-3), and the lowest in the Barycz River (1.10 ± 0.05 Bq m-3) and the Odra at Glogow (1.04 ± 0.06 Bq m-3). In summer the highest 210Po concentration was observed in Odra River at Widuchowa (1.79 ± 0.04 Bq m-3) and in the Nysa Klodzka River (2.00 ± 0.05 Bq m-3), and the lowest in the Odra at Gozdowice (1.10 ± 0.05 Bq m-3) and in the Barycz River (0.60 ± 0.09 Bq m-3). The highest quantity of polonium 210Po was transported to the Baltic Sea in spring, and the lowest in winter. It was calculated that the southern Baltic Sea, especially the Pomeranian Bay with the Szczecin Lagoon, receives 14.76 GBq 210Po annually. Among the Odra tributaries the highest surface runoff of 210Po was observed in autumn (up to 88 kBq km-2 quarter-1 for the Nysa Luzycka drainage area), and the lowest in summer (1 kBq km-2 quarter-1 for the Barycz drainage area). (authors)

  2. Modelling of Radiological Health Risks from Gold Mine Tailings in Wonderfonteinspruit Catchment Area, South Africa

    Directory of Open Access Journals (Sweden)

    Manny Mathuthu

    2016-06-01

    Full Text Available Mining is one of the major causes of elevation of naturally-occurring radionuclide material (NORM concentrations on the Earth’s surface. The aim of this study was to evaluate the human risk associated with exposure to NORMs in soils from mine tailings around a gold mine. A broad-energy germanium detector was used to measure activity concentrations of these NORMs in 66 soil samples (56 from five mine tailings and 10 from the control area. The RESidual RADioactivity (RESRAD OFFSITE modeling program (version 3.1 was then used to estimate the radiation doses and the cancer morbidity risk of uranium-238 (238U, thorium-232 (232Th, and potassium-40 (40K for a hypothetical resident scenario. According to RESRAD prediction, the maximum total effective dose equivalent (TEDE during 100 years was found to be 0.0315 mSv/year at year 30, while the maximum total excess cancer morbidity risk for all the pathways was 3.04 × 10−5 at year 15. The US Environmental Protection Agency considers acceptable for regulatory purposes a cancer risk in the range of 10−6 to 10−4. Therefore, results obtained from RESRAD OFFSITE code has shown that the health risk from gold mine tailings is within acceptable levels according to international standards.

  3. Modelling of Radiological Health Risks from Gold Mine Tailings in Wonderfonteinspruit Catchment Area, South Africa.

    Science.gov (United States)

    Mathuthu, Manny; Kamunda, Caspah; Madhuku, Morgan

    2016-01-01

    Mining is one of the major causes of elevation of naturally-occurring radionuclide material (NORM) concentrations on the Earth's surface. The aim of this study was to evaluate the human risk associated with exposure to NORMs in soils from mine tailings around a gold mine. A broad-energy germanium detector was used to measure activity concentrations of these NORMs in 66 soil samples (56 from five mine tailings and 10 from the control area). The RESidual RADioactivity (RESRAD) OFFSITE modeling program (version 3.1) was then used to estimate the radiation doses and the cancer morbidity risk of uranium-238 ((238)U), thorium-232 ((232)Th), and potassium-40 ((40)K) for a hypothetical resident scenario. According to RESRAD prediction, the maximum total effective dose equivalent (TEDE) during 100 years was found to be 0.0315 mSv/year at year 30, while the maximum total excess cancer morbidity risk for all the pathways was 3.04 × 10(-5) at year 15. The US Environmental Protection Agency considers acceptable for regulatory purposes a cancer risk in the range of 10(-6) to 10(-4). Therefore, results obtained from RESRAD OFFSITE code has shown that the health risk from gold mine tailings is within acceptable levels according to international standards. PMID:27338424

  4. Modelling of Radiological Health Risks from Gold Mine Tailings in Wonderfonteinspruit Catchment Area, South Africa

    Science.gov (United States)

    Mathuthu, Manny; Kamunda, Caspah; Madhuku, Morgan

    2016-01-01

    Mining is one of the major causes of elevation of naturally-occurring radionuclide material (NORM) concentrations on the Earth’s surface. The aim of this study was to evaluate the human risk associated with exposure to NORMs in soils from mine tailings around a gold mine. A broad-energy germanium detector was used to measure activity concentrations of these NORMs in 66 soil samples (56 from five mine tailings and 10 from the control area). The RESidual RADioactivity (RESRAD) OFFSITE modeling program (version 3.1) was then used to estimate the radiation doses and the cancer morbidity risk of uranium-238 (238U), thorium-232 (232Th), and potassium-40 (40K) for a hypothetical resident scenario. According to RESRAD prediction, the maximum total effective dose equivalent (TEDE) during 100 years was found to be 0.0315 mSv/year at year 30, while the maximum total excess cancer morbidity risk for all the pathways was 3.04 × 10−5 at year 15. The US Environmental Protection Agency considers acceptable for regulatory purposes a cancer risk in the range of 10−6 to 10−4. Therefore, results obtained from RESRAD OFFSITE code has shown that the health risk from gold mine tailings is within acceptable levels according to international standards. PMID:27338424

  5. 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

  6. 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

  7. Distribution, migration and potential risk of heavy metals in the Shima River catchment area, South China.

    Science.gov (United States)

    Gao, Lei; Chen, Jianyao; Tang, Changyuan; Ke, Zhiting; Wang, Jiang; Shimizu, Yuta; Zhu, Aiping

    2015-10-01

    The distribution, migration and potential risk of heavy metals in water and soil environments, related to city water supply, were investigated. Heavy metal concentrations in waters from the Shima River water ranged from not detected (n.d.) to 749 μg L(-1) for Mn, n.d. to 151 μg L(-1) for Ni, 7.00 to 494 μg L(-1) for Zn, n.d. to 93.0 μg L(-1) for Cu and n.d. to 9860 μg L(-1) for Fe. The highest concentration of heavy metals was found at an upstream site in February as a result of industrial effluent discharge. Groundwater (GW1-GW5) and soil (S1-S8) samples along the riverbank showed similar levels of contamination due to a close hydraulic relationship and frequent exchange of water, probably resulting in migration of heavy metals from river water to the aquifer and accumulation at the interface. The mean concentrations of heavy metals in soil profiles were in the ranges of 2.50-19.0 mg kg(-1) for As, 2.80-11.2 mg kg(-1) for Cd, 20.3-165 mg kg(-1) for Cr, 14.5-298 mg kg(-1) for Cu, 11.4-102 mg kg(-1) for Ni, 7.00-95.0 mg kg(-1) for Pb, 40.4-465 mg kg(-1) for Zn, 8.80 × 10(3)-21.8 × 10(3) mg kg(-1) for Fe, and 62.2-430 mg kg(-1) for Mn, showing severe soil pollution by Cd. LUMISTox testing and the potential ecological risk index (RI) were used to assess the potential for adverse ecological effects caused by heavy metals in water and soil media. River water samples posed slight acute toxicity to Vibrio fischeri with luminescence inhibition rates (LIRs) ranging from 24.6% to 38.4% in February. Elevated Zn and Cu concentrations significantly contributed to the toxicity. However, groundwater did not exhibit any toxicity to Vibrio fischeri. The severity of the potential ecological risk for individual metals (Er(i)) decreased in the order of Cd > Cu > Ni > As > Pb > Zn > Cr. RI values indicated that all soil samples in the study area posed a high level of ecological risk. Cd contributed significantly (95.5-98.9%) to potential ecological risk in soils. PMID:26308469

  8. Using GIS to Record and Analyse Historical Urban Areas

    Directory of Open Access Journals (Sweden)

    Maria Giannopoulou

    2014-05-01

    Full Text Available A significant part of the cultural heritage of towns and cities worldwide is the built heritage. The historic centre of several European cities has been preserved as an important part of the urban landscape. New analytical tools and concepts are thus required, which would enrich and expand the conventional methods and achieve sustainability of cultural heritage in any urban context, among which are Geographical Information Systems (GIS, digital mapping systems that link spatial and non – spatial data of landscape features, and can contribute substantially in documenting different urban features and furthermore in modelling the urban process and its impact on heritage regions. This paper is part of a wider research still in progress and refers to the creation of a specialised GIS, which includes a great range of geometric and descriptive information that can be used for the interpretation, monitoring, visualisation and evaluation of urban heritage areas. The case study of the paper is the Old Town of Xanthi, one of the most important examples of the 19th century’s urban civilization in Northern Greece. The paper focuses on the elaboration of the data concerning the built environment and more precisely to its systematic retrieval and import to the GIS system; moreover it examines 17 chosen variables using a combination of Multivariable analysis methods (Correspondence and Hierarchical Cluster Analysis. The analysis has shown the existence of four distinctive and very interesting groups which have their own specific characteristics. Ideas for further research include the collaboration with specialised sophisticated software which would facilitate the thorough examination, analysis and correlation of parameters involved, towards the principles of sustainable and smart city development. A significant part of the cultural heritage of towns and cities worldwide is the built heritage. The historic centre of several European cities has been preserved

  9. The inflow of uranium 234U and 238U from the Vistula River catchment area to the Baltic Sea

    International Nuclear Information System (INIS)

    .78 mg m-3 for total uranium). The values of 234U/238U activity ratio lie between 1.10-1.74. Annually, the southern Baltic Sea is enriched by about 507 GBq uranium isotopes 234U and 238U, with 490 GBq going to the Gdansk Bay and 16.5 GBq to Vistula Lagoon. The highest surface 238U runoff was observed in spring (to 1200 kBq km-2 quarter-1 for catchment's area), the lowest in summer for Bug with Narew catchment's area to 20 kBq km-2 quarter-1. These studies are very important for the inflow estimation of natural and anthropogenic alpha radionuclides to the Baltic Sea. (orig.)

  10. Popliteal artery injuries in an urban trauma center with a rural catchment area: do delays in definitive treatment affect amputation?

    Science.gov (United States)

    Simmons, Jon D; Gunter, Joseph W; Schmieg, Robert E; Manley, Justin D; Rushton, Fred W; Porter, John M; Mitchell, Marc E

    2011-11-01

    Extended length of time from injury to definitive vascular repair is considered to be a predictor of amputation in patients with popliteal artery injuries. In an urban trauma center with a rural catchment area, logistical issues frequently result in treatment delays, which may affect limb salvage after vascular trauma. We examined how known risk factors for amputation after popliteal trauma are affected in a more rural environment, where patients often experience delays in definitive surgical treatment. All adult patients admitted to the Level I trauma center, the University of Mississippi Medical Center, with a popliteal artery injury between January 2000 and December of 2007 were identified. Demographic information management and outcome data were collected. Body mass index, mangled extremity severity score (MESS), Guistilo open fracture score, injury severity score, and time from injury to vascular repair were examined. Fifty-one patients with popliteal artery injuries (53% blunt and 47% penetrating) were identified, all undergoing operative repair. There were nine amputations (17.6%) and one death. Patients requiring amputation had a higher MESS, 7.8 versus 5.3 (P amputation rate compared with those with penetrating trauma, 25.9 per cent versus 8.3 per cent (P = non significant). MESS, though not perfect, is the best predictor of amputation in patients with popliteal artery injuries. Morbid obesity is not a significant predictor for amputation in patients with popliteal artery injuries. Time from injury to repair of greater than 6 hours was not predictive of amputation. This study further demonstrates that a single scoring system should be used with caution when determining the need for lower extremity amputation.

  11. Residence times for surface waters in altered granite area: Example of the 'Furan' water catchment, East French Massif Central

    International Nuclear Information System (INIS)

    Full text: The topic of this study is to understand the behaviour of surface waters in a small catchment area (c.a. 3300 ha - altitudes ranging from 550m to 1300m). Six springs located in the southern part of the French Massif Central have been studied for two years. The 'Furan' watershed composed of metric arena overlays in a granitic and gneissic basement. Oxygen and Hydrogen stable isotope ratios were determined routinely. Tritium, carbon isotopes as well as alkalinity were punctually determined. Cations and anions were quantified using ICP-AES and ion chromatography. Further more, to better understand stable isotopes catchment's behavior, three years of daily rainwater sampling provide a well define local meteoric water line (collection at 400m asl). Moreover, two other LMWL were established, at 770m and 1100m to quantify spatial and altitudinal changes. Cations and anions content of springs are enriched regarding precipitation compositions (few mg/L), and the chemical content refers to low temperature reactions. Total dissolved ions range between 30 mg/L and 130 mg/L. Few alkalinity values were measured, from 1 to 7 mg/L as bicarbonate alkalinity, but there is no clear evidence that they match real values, sulphate content being higher. Ionic mass balance, based on pe redox equilibrium, were made using PhreeQC and appears to be good for half of the springs (4+ content might be related to agricultural impact. Inverse modelling suggests interaction with minerals such as kaolinite, chlorite, K-feldspar, underlining reactions between percolating water and altered granites. From rainwater isotopic records, altitudinal variations are too small to modify both slope and D-excess of the LMWL. So the monthly mean of three years record is taken as representative of local rains and leads to δD=7.4δ18O+3.8 (r2=0.96). During the year 2003 occurred a 40% decrease of pluviometry/mean annual pluviometry: high isotopes values recorded for these summer months lead to a

  12. Multi-isotope approach for the identification and characterisation of nitrate pollution sources in the Marano lagoon (Italy) and parts of its catchment area

    International Nuclear Information System (INIS)

    Highlights: • Multi-tracer approach for the identification and characterisation of nitrate sources in a lagoon environment was used. • Different nitrate pollution sources in the lagoon were identified. • Isotopes in nitrate and boron were applied to distinguish different anthropogenic pollution sources. • Atmospheric depositions (based on Δ17O analyses of nitrate) were recognized as additional nitrate source. - Abstract: A multi-isotope approach has been used in the Marano lagoon (NE Italy) and parts of its catchment area to identify causes of increased NO3- pollution. The hydrogeochemical features of different water types and potential sources of NO3- were characterized using the isotopic composition of NO3- (δ15N, δ18O, and Δ17O) and other source-related species such as B (δ11B), water (δ2H and δ18O) and SO42- (δ34S and δ18O). Water samples from the lagoon, its tributary rivers, the groundwater up-welling line, groundwater, sewer pipes, and open sea water have been collected at quarterly intervals in the years 2009–2010. The results indicate that the NO3- load in the lagoon was not only derived from agricultural activities but also from other sources such as urban waste water, in situ nitrification and atmospheric deposition. The δ34S signature in the lagoon clearly denotes the largely prevailing origin of aqueous SO42- from seawater, and practically points to the absence of any appreciable redox process involving S species in the lagoon. It also supports the existence of a connection between the lagoon and the nearby Tagliamento river

  13. 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

    storage characteristics are strongly dependent on the chosen method. However, the overall ranking of the catchments among the methods is quite similar, despite the derived catchment storage of one catchment may differ by one to two orders of magnitude. Surprisingly, the high elevation catchments generally show a much larger storage than most of the low elevation catchments. To investigate this surprising result further, we analyzed the effect of climate on the derived catchment storage in more detail, since an additional snow storage with the resulting melt period in spring may produce an large dynamic storage due to the concentrated input of water. We both used subsamples of discharge to divide the storage in snow or rain triggered storage and changed the climate input either to a rainfall or snowmelt dominated climate and compared the storage among the catchments based on a similar climate signal. We finally develop a framework for assessing and comparing catchment storages among catchments in different climates, geologies and with different physiographic characteristics. These analyses also provided more insights into the larger storage in mountainous catchments and its importance to catchments functions.

  14. 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.

  15. Prioritizing erosion-prone areas in hills using remote sensing and GIS — a case study of the Sukhna Lake catchment, Northern India

    Science.gov (United States)

    Shrimali, S. S.; Aggarwal, S. P.; Samra, J. S.

    Traditionally, assessment of productivity of land took priority over all other aspects of evaluating land use performance. Presently, the effects of land use on the quality of the environment and environmental sustainability of production systems have become the major issues. In hills, the terrain conditions aggravate erosion-induced land degradation. Judicious allocation of available resources for sustainable production requires mapping, monitoring and prioritizing the areas based on their susceptibility to degradation. Remote sensing and Geographic Information Systems are effective tools for inventory, monitoring and management of spatially distributed resources. This paper presents a case study of the 42 km 2 Sukhna Lake catchment in the Shiwalik hills conducted for the delineation and prioritization of erosion-prone areas using RS and Geographic Information Systems. Multi-spectral IRS ID-LISS III data acquired in March 1998 was used for the supervised digital classification of the land use/land cover type. The catchment was classified in six land use classes: forest, agriculture, scrub, barren hills, streambed and settlements. These classes were divided into sub-classes based on the cover characteristics. Using the U.S. Soil Conservation Service curve number method, runoff potential of each delineated hydrologic unit was computed in a grid-based analysis using an ARC/INFO GIS. Erosion-prone areas were classified further by integration of a digital elevation model or DEM-derived slope, aspect and flow length. To get an ordered priority of the erosion-prone areas, a cumulative erosion index was computed from the rating given to the three main causative factors, ie, slope, soil erodibility, and land cover, on a scale of 1-7 for each grid. The cumulative index was further classified in four classes for spatial representation of the erosion-prone areas on the catchment map. The study revealed that 32.9 percent of the catchment area is susceptible to high or very

  16. Trends in the chemistry of atmospheric deposition and surface waters in the Lake Maggiore catchment

    OpenAIRE

    M. Rogora; Marchetto, A.; Mosello, R

    2001-01-01

    International audience; The Lake Maggiore catchment is the area of Italy most affected by acid deposition. Trend analysis was performed on long-term (15-30 years) series of chemical analyses of atmospheric deposition, four small rivers draining forested catchments and four high mountain lakes. An improvement in the quality of atmospheric deposition was detected, due to decreasing sulphate concentration and increasing pH. Similar trends were also found in high mountain lakes and in small river...

  17. Trends in the chemistry of atmospheric deposition and surface waters in the Lake Maggiore catchment

    OpenAIRE

    M. Rogora; Marchetto, A.; Mosello, R

    2001-01-01

    The Lake Maggiore catchment is the area of Italy most affected by acid deposition. Trend analysis was performed on long-term (15-30 years) series of chemical analyses of atmospheric deposition, four small rivers draining forested catchments and four high mountain lakes. An improvement in the quality of atmospheric deposition was detected, due to decreasing sulphate concentration and increasing pH. Similar trends were also found in high mountain lakes and in small rivers. Atmospheric depositio...

  18. Residence times and age distributions of spring waters at the Semmering catchment area, Eastern Austria, as inferred from tritium, CFCs and stable isotopes.

    Science.gov (United States)

    Han, Liangfeng; Hacker, Peter; Gröning, Manfred

    2007-03-01

    The groundwater system in the mountainous area of Semmering, Austria, was studied by environmental tracers in several karst springs. The tracers used included stable isotopes ((18)O, (2)H), tritium ((3)H) and chlorofluorocarbons (CFCs). The tracers provided valuable information in regard to (1) the mean altitude of the spring catchment areas; (2) the residence time and age distribution of the spring waters; and (3) the interconnection of the springs to a sinkhole. The combination of the stable isotopic data and the topography/geology provided the estimates of the mean altitudes of the catchment areas. Based on the stable isotopic data the recharge temperature of the spring waters was estimated. The smoothing of precipitation's isotopic signal in spring discharge provided information on the minimum transit time of the spring waters. Due to short observation time, (3)H data alone cannot be used for describing the mean residence time of the karst waters. CFCs, though useful in recognizing the co-existence of young (post-1993) water with old (CFC-free) water, could not be used to resolve age distribution models. It is shown in this article, however, that the combined use of tritium and CFCs can provide a better assessment of models to account for different groundwater age distributions. In Appendix A, a simplified method for collecting groundwater samples for the analysis of CFCs is described. The method provides a real facilitation for fieldwork. Test data are given for this sampling method in regard to potential contamination by atmospheric CFCs.

  19. Soil and Water Resources and Land Sustainable Productivity in the Catchment Area with Intensive Management in Hilly Red Soil Regions,China

    Institute of Scientific and Technical Information of China (English)

    HUANG Dao-you; WANG Ke-lin; CHEN Gui-qiu; HUANG Min; PENG Ting-bo

    2004-01-01

    Taking an example of Majiayu Catchment Area (14.15 ha) in Taoyuan County of Hunan Province, the soil and water resources dynamics, fertility evolution characteristics and land productivity changing situation were studied. Fixed observation results from 1993 to 2002 showed that pools covering about 15% of total area could store up 10% of surface runoff, keep 78.1% of eroded soil and 65.4% of lost nutrients. The yearly ratio of interception and evapotranspiration in land, storage in pools and drainage was 7:2:1,which ensured the resources and nutrients equilibrium and a benign recycle in the catchment area system, and benefited the aquatic culture and helped to resist seasonal drought. Moreover, the results showed that soil erosion modulus decreased significantly,equal to or lower than soil loss tolerance (≤500 t km-2) in reddish yellow soil regions.Soil organic matter, total and available N content in sloping land, dryland and paddy field increased steadily (>10%); water storage enhanced by more than 20% in sloping land and dryland in drought season; crop production increased by more than 20%; and production of trees, fruits, tea and fish as well as land productivity increased yearly.

  20. 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

  1. Advancing Land-Sea Conservation Planning: Integrating Modelling of Catchments, Land-Use Change, and River Plumes to Prioritise Catchment Management and Protection.

    Science.gov (United States)

    Álvarez-Romero, Jorge G; Pressey, Robert L; Ban, Natalie C; Brodie, Jon

    2015-01-01

    Human-induced changes to river loads of nutrients and sediments pose a significant threat to marine ecosystems. Ongoing land-use change can further increase these loads, and amplify the impacts of land-based threats on vulnerable marine ecosystems. Consequently, there is a need to assess these threats and prioritise actions to mitigate their impacts. A key question regarding prioritisation is whether actions in catchments to maintain coastal-marine water quality can be spatially congruent with actions for other management objectives, such as conserving terrestrial biodiversity. In selected catchments draining into the Gulf of California, Mexico, we employed Land Change Modeller to assess the vulnerability of areas with native vegetation to conversion into crops, pasture, and urban areas. We then used SedNet, a catchment modelling tool, to map the sources and estimate pollutant loads delivered to the Gulf by these catchments. Following these analyses, we used modelled river plumes to identify marine areas likely influenced by land-based pollutants. Finally, we prioritised areas for catchment management based on objectives for conservation of terrestrial biodiversity and objectives for water quality that recognised links between pollutant sources and affected marine areas. Our objectives for coastal-marine water quality were to reduce sediment and nutrient discharges from anthropic areas, and minimise future increases in coastal sedimentation and eutrophication. Our objectives for protection of terrestrial biodiversity covered species of vertebrates. We used Marxan, a conservation planning tool, to prioritise interventions and explore spatial differences in priorities for both objectives. Notable differences in the distributions of land values for terrestrial biodiversity and coastal-marine water quality indicated the likely need for trade-offs between catchment management objectives. However, there were priority areas that contributed to both sets of objectives. Our

  2. Chemical composition of natural waters of contaminated area: The case for the Imandra Lake catchment (the Kola Peninsula)

    Science.gov (United States)

    Evtyugina, Z. A.; Guseva, N. V.; Kopylova, J. G.; A, Vorobeva D.

    2016-03-01

    The study of the current chemical composition of natural waters in the eastern and western parts of the Imandra Lake catchment was performed using ion chromatography, potentiometry and inductively coupled plasma mass spectrometry. It was found that the content of trace elements in the surface water is considerably higher than that in the groundwater. The nickel and copper concentrations exceed the background levels over 19 and 2 times respectively in groundwater, and 175 and 61 times in the surface waters. These data show that the Severonikel influences negatively air and surface water.

  3. Is the impact of future climate change on hydro-climatic conditions significant? - A climate change study for an Eastern European catchment area.

    Science.gov (United States)

    Pavlik, Dirk; Söhl, Dennis; Bernhofer, Christian

    2014-05-01

    The future change of climatic conditions is, among others, closely linked to future hydrological changes. One important aspect of these issues is the question of future availability of water resources. A changed climatic water balance, as indicator for potential water availability, has far-reaching consequences for the water cycle, hydrological conditions, ecology, water management, the energy business, agriculture and forestry, and for anthropogenic use of the river. We generated regional climate projections via dynamic downscaling for the catchment area of the Western Bug river in the border area of Poland, Belarus, and Ukraine. The hydro-climatic conditions of the past and their projected future changes in the catchment were analyzed based on 2m-temperature, precipitation, potential evaporation and climatic water balance. Up to the end of the century, the used IPCC scenarios B1 and A2 lead to warming for each month in the long-term mean, with highest warming rates in winter. Instead, precipitation does not change in the long-term yearly mean. However, the intra-annual distribution of monthly precipitation sums shifts with an increase in winter and a strong decrease in summer. Combined, this leads to a changed climatic water balance with a stronger deficit in summer and a higher gain in winter. Particular in the south-eastern part of the catchment, the summer deficit cannot be compensated within the annual cycle. It raised the question: are these changes statistically significant and thus robust for use in further impact studies? Using a significance analysis, we found, that climatic changes in temperature, precipitation and potential evaporation and thus the climatic water balance change is most significant for scenario A2 from 2071 to 2100. The temperature changes are significant throughout the year. For the other variables changes are most significant in the late summer months (July, August, and September) and the winter months (December, January, and February

  4. Evolution of Hydrological Drought in Human Disturbed Areas: A Case Study in the Laohahe Catchment, Northern China

    Directory of Open Access Journals (Sweden)

    Yi Liu

    2016-01-01

    Full Text Available A case study on the evolution of hydrological drought in nonstationary environments is conducted over the Laohahe catchment in northern China. Using hydrometeorological observations during 1964–2009, meteorological and hydrological droughts are firstly analyzed with the threshold level method. Then, a comprehensive analysis on the changes within the catchment is conducted on the basis of hydrological variables and socioeconomic indices, and the whole period is divided into two parts: the undisturbed period (1964–1979 and the disturbed period (1980–2009. A separating framework is further introduced to distinguish droughts induced by different causes, that is, the naturalized drought and human-induced drought. Results showed that human activities are more inclined to play a negative role in aggravating droughts. Drought duration and deficit volume in naturalized conditions are amplified two to four times and three to eight times, respectively, when human activities are involved. For the two dry decades 1980s and 2000s, human activities have caused several consecutive drought events with rather long durations (up to 29 months. These results reflect the considerable impacts of human activities on hydrological drought, which could provide some theoretical support for local drought mitigation and water resources management.

  5. 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

  6. Propagation of drought in a groundwater fed catchment, the Pang in UK

    NARCIS (Netherlands)

    Tallaksen, L.; Hisdal, H.; Lanen, van H.A.J.

    2006-01-01

    Regional drought characteristics, such as the area covered by drought and the total deficit over that area, are important measures of the severity of a drought event. Gridded, monthly data from the Pang catchment, UK, are analysed here to study the spatial aspects of the drought as it propagates fro

  7. Management and Area-wide Evaluation of Water Conservation Zones in Agricultural Catchments for Biomass Production, Water Quality and Food Security

    International Nuclear Information System (INIS)

    Global land and water resources are under threat from both the agricultural and urban development to meet increased demand for food and from the resulting degradation of the environment. Poor crop yields due to water stress is one of the main reasons for the prevailing hunger and rural poverty in parts of the world. The Green Revolution of the 1960s and 1970s particularly in Latin America and Asia resulted in increased agricultural production and depended partly on water management. In the future, most food will still need to come from rain-fed agriculture. Water conservation zones in agricultural catchments, particularly in rainfed areas, play an important role in the capture and storage of water and nutrients from farmlands and wider catchments, and help improve crop production in times of need in these areas. Water conservation zones are considered to be an important part of water resource management strategies that have been developed to prevent reservoir siltation, reduce water quality degradation, mitigate flooding, enhance groundwater recharge and provide water for farming. In addition to making crop production possible in dry areas, water conservation zones minimize soil erosion, improve soil moisture status through capillary rise and enhance soil fertility and quality. These water conservation zones include natural and constructed wetlands (including riparian wetlands), farm ponds and riparian buffer zones. The management of water conservation zones has been a challenge due to the poor understanding of the relationship between upstream land use and the functions of these zones and their internal dynamics. Knowledge of sources and sinks of water and redefining water and nutrient budgets for water conservation zones are important for optimizing the capture, storage and use of water and nutrients in agricultural landscapes. The overall objective of this coordinated research project (CRP) was to assess and enhance ecosystem services provided by wetlands, ponds

  8. REXPO: A catchment model designed to understand and simulate the loss dynamics of plant protection products and biocides from agricultural and urban areas

    Science.gov (United States)

    Wittmer, I. K.; Bader, H.-P.; Scheidegger, R.; Stamm, C.

    2016-02-01

    During rain events, biocides and plant protection products are transported from agricultural fields but also from urban sources to surface waters. Originally designed to be biologically active, these compounds may harm organisms in aquatic ecosystems. Although several models allow either urban or agricultural storm events to be predicted, only few combine these two sources, and none of them include biocide losses from building envelopes. This study therefore aims to develop a model designed to predict water and substance flows from urban and agricultural sources to surface waters. We developed a model based on physical principles for water percolation and substance flow including micro- (also called matrix-) and macropore-flows for the agricultural areas together with a model representing sources, sewer systems and a wastewater treatment plant for urban areas. In a second step, the combined model was applied to a catchment where an extensive field study had been conducted. The modelled and measured discharge and compound results corresponded reasonably well in terms of quantity and dynamics. The total cumulative discharge was only slightly lower than the total measured discharge (factor 0.94). The total modelled losses of the agriculturally used herbicide atrazine were slightly lower (∼25%) than the measured losses when the soil pore water distribution coefficient (describing the partition between soil particles and pore water) (Kd) was kept constant and slightly higher if it was increased with time. The modelled urban losses of diuron from facades were within a factor of three with respect to the measured values. The results highlighted the change in importance of the flow components during a rain event from urban sources during the most intensive rain period towards agricultural ones over a prolonged time period. Applications to two other catchments, one neighbouring and one on another continent showed that the model can be applied using site specific data for

  9. Is organizational change associated with increased rates of readmission to general hospital in suicide attempters? A 10-year prospective catchment area study.

    Science.gov (United States)

    Mehlum, Lars; Jørgensen, Trond; Diep, Lien My; Nrugham, Latha

    2010-01-01

    The objective of this study was to examine predictors for readmissions in patients admitted to a general hospital emergency ward for suicide attempts before and after organizational changes potentially affecting the chain of care. Socio-demographic and clinical variables were collected by clinicians from 1997 thru 2007. Data from the periods before and after 2004--when the hospital changed its catchment area--were compared. A substantial increase in readmission rates in the period after the organizational change was observed. This increase was not associated with any of the socio-demographic or clinical patient characteristics. Although no causal connection can be inferred, the observed association between organizational change and readmission rates could indicate that established post-discharge care systems for suicide attempters may be vulnerable to such change. PMID:20455152

  10. Mediating effect of mental disorders in the pathway between life events and mental health services use: results from the Baltimore Epidemiologic Catchment Area study.

    Science.gov (United States)

    Maulik, Pallab K; Eaton, William W; Bradshaw, Catherine P

    2010-03-01

    This study assessed the role of some common mental health conditions as mediators in the pathway between suffering life events and using mental health services. The participants were from the Baltimore Epidemiologic Catchment Area cohort, interviewed in 1993 to 1996 and 2004 to 2005. Longitudinal data analysis was used to identify models with significant mediation. Only alcohol abuse/dependence disorder was a significant mediator in the pathway between suffering a life-threatening illness and using mental health services in a general medical setup. Female gender, being more than 65 years old, prior use of services and availability of health insurance were some of the factors that significantly predicted service use in that model. Some of other factors like social networks and social support, attitudes towards services, and stigma, may play a role in determining service use. Future research should investigate the role of such factors as mediators for mental health service use. PMID:20215995

  11. Understanding the relationship between sediment connectivity and spatio-temporal landscape changes in two small catchments

    Science.gov (United States)

    Giuseppina Persichillo, Maria; Meisina, Claudia; Cavalli, Marco; Crema, Stefano; Bordoni, Massimiliano

    2016-04-01

    The degree of linkage between the sediments sources and downstream areas (i.e., sediment connectivity) is one of the most important properties controlling landscape evolution. Many factors have been found to affect sediment connectivity, especially at the catchment scale. In particular, the degree of linkage between different areas within a catchment depends largely on the morphological complexity of the catchment (relief, terrain roughness, stream network density and catchment shape) and the combined effects of vegetation, such as land use changes and land abandonment. Moreover, the analysis of the spatial distribution of sediment connectivity and its temporal evolution can be also useful for the characterization of sediment source areas. Specifically, these areas represent sites of instability and their connectivity influences the probability that a local on-site effect could propagate within a multiple-events feedback system. Within this framework, the aim of this study is to apply a geomorphometric approach to analyze the linkage between landscape complexity and the sediment connectivity at the catchment scale. Moreover, to assess sediment delivery, the index of connectivity (IC) proposed by Cavalli et al. (2013) was used to evaluate the potential connection of sediment source areas with the main channel network. To better understand the relationship between morphological complexity of the catchment's landscape and the sediment spatial distribution and mobilization, two catchments with different size and geomorphological and land use characteristics were analysed: the Rio Frate and Versa catchments (Oltrepo Pavese, Southern Lombardy, Italy). Several shallow landslides, which represents the main sediment source area type in the catchments, were triggered especially in the period from 2009 to 2013. Moreover, relevant modification of land use and drainage system during last decades, especially related to land abandonment, have conditioned the sediment connectivity

  12. Combining AHP with GIS for landfill site selection: a case study in the Lake Beyşehir catchment area (Konya, Turkey).

    Science.gov (United States)

    Sener, Sehnaz; Sener, Erhan; Nas, Bilgehan; Karagüzel, Remzi

    2010-11-01

    Landfills are the most common method for the disposal of municipal solid waste (MSW) in Turkey. However, determining the location of landfill sites is a difficult and complex process because it must combine social, environmental and technical parameters. Additionally, it depends on several criteria and regulations. The main objective of this study was to select of a landfill site for the Lake Beyşehir catchment area. The Beyşehir Lake is the largest freshwater lake and drinking water reservoir in Turkey, but there is no controlled landfill site in the region. Therefore, the landfill site should be determined such that the lake is protected. To determine the most suitable landfill site, an analytical hierarchy process (AHP) was combined with a geographic information system (GIS) to examine several criteria, such as geology/hydrogeology, land use, slope, height, aspect and distance from settlements, surface waters, roads, and protected areas (ecologic, scientific or historic). Each criterion was evaluated with the aid of AHP and mapped by GIS. Data were assorted into four suitability classes within the study area, i.e., high, moderate, low and very low suitability areas, which represented 3.24%, 7.55%, 12.70% and 2.81%, of the study area, respectively. Additionally, 73.70% was determined to be completely unsuitable for a landfill site. As a result, two candidate landfill sites are suggested and discussed. The final decision for landfill site selection will require more detailed field studies. PMID:20594819

  13. A population-based audit of ethnicity and breast cancer risk in one general practice catchment area in North London, UK: implications for practice

    Directory of Open Access Journals (Sweden)

    Ferris Michelle

    2007-09-01

    Full Text Available Abstract Objectives To conduct a pilot population-based study within a general practice catchment area to determine whether the incidence of breast cancer was increased in the Ashkenazi population. Design Population-based cohort study. Setting A single general practice catchment area in North London. Participants 1947 women over the age of 16 who responded to a questionnaire about ethnicity and breast cancer. Main outcome measures Incidence of breast cancer, ethnicity. Results This study showed a 1.5-fold (95% CI 0.93–2.39 increase in breast cancer risk in the Ashkenazim compared with the non-Ashkenazi white population. The increased incidence was for both premenopausal and postmenopausal breast cancer (expected incidence pre:post is 1:4 whereas in the Ashkenazim it was 1:1; 51 and 52% of cases respectively. This increase was not shown in the Sephardim. Asians had a reduction in incidence (OR = 0.44; 95% CI 0.10–1.89. Results were adjusted for other risk factors for breast cancer. Conclusion This study showed a 1.5-fold increase in breast cancer rates in Ashkenazim compared with the non-Jewish white population when adjusted for age (i.e. corrections were made to allow comparison of age groups and this is not observed in the Sephardic population. The proportion of premenopausal breast cancer was just over double that of the general population. This is the first general practice population-based study in the UK to address this issue and has implications for general practitioners who care for patients from the Ashkenazi community.

  14. Estimation of nitrogen budgets for contrasting catchments at the landscape scale

    Directory of Open Access Journals (Sweden)

    E. Vogt

    2013-01-01

    Full Text Available A comprehensive assessment of nitrogen (N flows at the landscape scale is fundamental to understand spatial interactions in the N cascade and to inform the development of locally optimised N management strategies. To explore these interactions, complete N budgets were estimated for two contrasting hydrological catchments (dominated by agricultural grassland vs. semi-natural peat-dominated moorland, forming part of an intensively studied landscape in southern Scotland. Local scale atmospheric dispersion modelling and detailed farm and field inventories provided high resolution estimations of input fluxes. Direct agricultural inputs (i.e. grazing excreta, N2 fixation, organic and synthetic fertiliser accounted for most of the catchment N inputs, representing 82% in the grassland and 62% in the moorland catchment, while atmospheric deposition made a significant contribution, particularly in the moorland catchment, contributing 38% of the N inputs. The estimated catchment N budgets highlighted areas of key uncertainty, particularly N2 exchange and stream N export. The resulting N balances suggest that the study catchments have a limited capacity to store N within soils, vegetation and groundwater. The "catchment N retention", i.e. the amount of N which is either stored within the catchment or lost through atmospheric emissions, was estimated to be 13% of the net anthropogenic input in the moorland and 61% in the grassland catchment. These values contrast with regional scale estimates: Catchment retentions of net anthropogenic input estimated within Europe at the regional scale range from 50% to 90%, with an average of 82% (Billen et al., 2011. This study emphasises the need for detailed budget analyses to identify the N status of European landscapes.

  15. Groundwater as an emergency source for drought mitigation in the Crocodile River catchment, South Africa

    Directory of Open Access Journals (Sweden)

    F. E. F. Mussá

    2014-03-01

    and environmental damages to the society. In this study, we assess the drought intensity and severity and the groundwater potential to be used as a supplement source of water to mitigate drought impacts in the Crocodile River catchment, a water-stressed sub-catchment of the Incomati River catchment in South Africa. The research methodology consists mainly of three parts. First, the spatial and temporal variation of the meteorological and hydrological drought severity and intensity over the catchment were evaluated. The Standardized Precipitation Index (SPI was used to analyse the meteorological drought and the Standardized Runoff Index (SRI was used for the hydrological drought. Second, the water deficit in the catchment during the drought period was computed using a simple water balance method. Finally, a groundwater model was constructed in order to assess the feasibility of using groundwater as an emergency source for drought impact mitigation. Results show that the meteorological drought severity varies accordingly with the precipitation; the low rainfall areas are more vulnerable to severe meteorological droughts (lower and upper crocodile. Moreover, the most water stressed sub-catchments with high level of water uses but limited storage, such as the Kaap located in the middle catchment and the Lower Crocodile sub-catchments are those which are more vulnerable to severe hydrological droughts. The analysis of the potential groundwater use during droughts showed that a deficit of 97 Mm3 yr−1 could be supplied from groundwater without considerable adverse impacts on the river base flow and groundwater storage. Abstraction simulations for different scenarios of extremely severe droughts reveal that it is possible to use groundwater to cope with the droughts in the catchment. However, local groundwater exploitation in Nelspruit and White River sub-catchment will cause large drawdowns (> 10 m and high base flow reduction (> 20%. This case study shows that

  16. Estimation of nitrogen budgets for contrasting catchments at the landscape scale

    Directory of Open Access Journals (Sweden)

    E. Vogt

    2012-07-01

    Full Text Available A comprehensive assessment of nitrogen (N flows at the landscape scale is fundamental to understand spatial interactions in the N cascade and to inform the development of locally optimised N management strategies. To explore this interactions, complete N budgets were estimated for two contrasting hydrological catchments (dominated by agricultural grassland vs. semi-natural peat-dominated moorland, forming part of an intensively studied landscape in southern Scotland. Local scale atmospheric dispersion modelling and detailed farm and field inventories provided high resolution estimations of input fluxes. Agricultural inputs (i.e. grazing excreta, organic and synthetic fertiliser accounted for most of the catchment N inputs with 80% in the grassland and 57% in the moorland catchment, while atmospheric deposition made a significant contribution, particularly in the moorland catchment with 38% of the N inputs. The estimated catchment N budgets highlighted areas of key uncertainty, particularly N2 emissions from denitrification and stream N export. The resulting N balances suggest that the study catchments have a limited capacity to store N within soils, vegetation and groundwater. The "catchment N retention", i.e. the amount of N which is either stored within the catchment or lost through atmospheric emissions, was estimated to be 3% of the net anthropogenic input in the moorland and 55% in the grassland catchment. These values contrast with regional scale estimates: catchment retentions of net anthropogenic input estimated within Europe at the regional scale range from 50% to 90% with an average of 82% (Billen et al., 2011. This study emphasises the need for detailed budget analyses to identify the N status of European landscapes.

  17. Mineralogical analyses in various caves from the Băile Herculane area, the Cerna Passage

    Directory of Open Access Journals (Sweden)

    Ştefan Marincea

    2010-01-01

    Full Text Available In this paper we intend to show results from the mineralogical analyses performed on samples from three caves in the Baile Herculane area. All minerals presented here are described for the first time in the cave from which they were sampled.

  18. 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

  19. Threshold Value Research about Catchment Area of Drainage Network of Hetao Irrigated Area%河套灌区排水网络集水面积闽值研究

    Institute of Scientific and Technical Information of China (English)

    周钧迪; 马锦; 宋密; 程一平; 张涛

    2012-01-01

    流域数字水系网络提取的精度,通常与所使用的数字高程图(DEM)的精度和集水面积阈值的大小有关。在给定的DEM图上,数字水系的精度基本上取决于集水面积阈值的设置。首先介绍了几种确定阈值大小的方法,然后应用其中的“河网密度”法来对河套灌区的排干沟的水系网络进行提取。结果表明,该方法能很好地应用于灌区水系网络的合理提取。%The accuracy extraction of basins stream cision and the the threshold value of catchment area. ital stream digital network basically depends on how digital network usually is related to the DEM pre- In a givend DEM map, the precision of the dig- to set the threshold value of the catchment area.This paper first introduces several determine method of t the threshold value , then apply the "river network density" method to the extraction of drainage network for hetao irrigated area . The results show that the method can be used in reasonable network extraction for drainage network of irrigation.

  20. Hydrological change during the last 600 years as observed from landscape analysis and historical maps: a case study from the Nete catchment, Campine area, NE-Belgium

    Science.gov (United States)

    Beerten, Koen; Leterme, Bertrand

    2015-04-01

    Reliably predicting the future state of the hydrological system under transient climate and land use conditions is a major challenge. Hydrological models are usually calibrated and validated for a short time period (e.g. 30 years), for conditions that are similar to today's. In order to test model performance for future (unverifiable) projections, palaeohydrological modelling is first needed to build confidence in model output under different conditions. One of the major challenges of palaeohydrological modelling is the acquisition of verification data that is representative for the past state(s) of the hydrological system. Here, we present the reconstructed evolution of the groundwater table depth over the last six centuries, in a sandy interfluvium (20 km² with altitude varying between 16 m and 28 m a.s.l.) of the Nete catchment. For periods before 1770 AD, the altitude (depth) of blown-out surfaces in the drift sand landscape is used as a proxy for the average highest groundwater level. These surfaces are generally interpreted as the lower limit for wind erosion. Soil profiles investigations where these surfaces are overblown by younger drift sand show that they were created in the time period between ca. 1400 AD and 1600 AD. For younger periods, historical maps were analysed for the presence of surface water features, such as fens (shallow lakes that are groundwater fed in this sandy landscape under temperate climate), marshes and wetlands. The results clearly show declining water levels in the second half of the 19th century, i.e., between 1854 AD and 1909 AD. The decline is most pronounced for the higher areas of the interfluve (drift sand landscape) and becomes less clear towards the floodplains. The amount of groundwater level decline is 1-2 m on average. The cause for the synchronous groundwater level drop seems to be linked to land use and land cover changes during that period. In the time interval between 1854 AD and 1909 AD, the total length of drains

  1. Experimental Analyses of Yellow Tuff Spandrels of Post-medieval Buildings in the Naples Area

    International Nuclear Information System (INIS)

    Experimental analyses have been carried out on tuff masonry specimens in order to investigate the structural behaviour of historical buildings in the Naples area (Southern Italy). Spandrels of post-medieval buildings (late XVI to early XX century) have been analysed, with emphasis on morphological characteristics according to chronological indicators. Results of the experimentation on scaled models (1:10) are discussed and the better behaviour of historical masonry typologies on respect to the modern one is highlighted. Comparison with theoretical formulations of ultimate shear resistance are provided too

  2. The role of climatic and terrain attributes in estimating baseflow recession in tropical catchments

    Directory of Open Access Journals (Sweden)

    J. L. Peña-Arancibia

    2010-07-01

    Full Text Available The understanding of low flows in rivers is paramount more than ever as demand for water increases on a global scale. At the same time, limited streamflow data to investigate this phenomenon, particularly in the tropics, makes the provision of accurate estimations in ungauged areas an ongoing research need. This paper analysed the potential of climatic and terrain attributes of 167 tropical and sub-tropical unregulated catchments to predict baseflow recession rates. Climatic attributes included annual and seasonal indicators of rainfall and potential evapotranspiration. Terrain attributes included indicators of catchment shape, morphology, land cover, soils and geology. Stepwise regression was used to identify the best predictors for baseflow recession coefficients (kbf. Mean annual rainfall (MAR and aridity index (AI were found to explain 49% of the spatial variation of kbf. The rest of climatic indices plus average catchment slope (SLO and tree cover were also good predictors, but co-correlated with MAR. Catchment elongation (CE, a measure of catchment shape, was also found to be statistically significant, although weakly correlated. An analysis of clusters of catchments of smaller size, showed that in these areas, presumably with some similarity of soils and geology due to proximity, residuals of the regression could be explained by SLO and CE. The approach used provides a~potential alternative for kbf parameterisation in ungauged areas.

  3. Sediment accumulation rates and high-resolution stratigraphy of recent fluvial suspension deposits in various fluvial settings, Morava River catchment area, Czech Republic

    Science.gov (United States)

    Sedláček, Jan; Bábek, Ondřej; Kielar, Ondřej

    2016-02-01

    We present a comprehensive study concerning sedimentary processes in fluvial sediment traps within the Morava River catchment area (Czech Republic) involving three dammed reservoirs, four meanders and oxbow lakes, and several natural floodplain sites. The objective of the study was to determine sediment accumulation rates (SAR), estimate erosion rates, calculating these using a combination of the 137Cs method and historical data. Another purpose of this study was to provide insight into changing erosion and accumulation rates over the last century. Extensive water course modifications were carried out in the Morava River catchment area during the twentieth century, which likely affected sedimentation rates along the river course. Other multiproxy stratigraphic methods (X-ray densitometry, magnetic susceptibility, and visible-light reflectance spectrometry) were applied to obtain additional information about sediment infill. Sediment stratigraphy revealed distinct distal-to-proximal patterns, especially in reservoirs. Granulometrically, silts and sandy silts prevailed in sediments. Oxbow lakes and meanders contained larger amounts of clay and organic matter, which is the main difference between them and reservoirs. Pronounced 137Cs peaks were recorded in all studied cores (maximum 377 Bq·kg- 1), thus indicating Chernobyl fallout from 1986 or older events. Calculated sediment accumulation rates were lowest in distal parts of reservoirs (0.13-0.58 cm/y) and floodplains (0.45-0.88 cm/y), moderately high rates were found in proximal parts of reservoirs and oxbow lakes (2.27-4.4 cm/y), and the highest rates in some oxbow lakes located near the river (6-8 cm/y). The frequency of the inundation still can be high in some natural areas as in the Litovelské Pomoraví protected area, whereas the decreasing frequency of the inundation in other modified parts can contribute to a lower sedimentation rate. The local effects such as difference between SARs in oxbow lakes and

  4. Runoff generation in a Mediterranean semi-arid landscape: Thresholds, scale, rainfall and catchment characteristics

    Science.gov (United States)

    Ries, Fabian; Schmidt, Sebastian; Sauter, Martin; Lange, Jens

    2016-04-01

    Surface runoff acts as an integrated response of catchment characteristics and hydrological processes. In the Eastern Mediterranean region, a lack of runoff data has hindered a better understanding of runoff generation processes on the catchment scale, despite the importance of surface runoff as a water resource or flood hazard. Our main aim was to identify and explain differences in catchment runoff reactions across a variety of scales. Over a period of five years, we observed runoff in ephemeral streams of seven watersheds with sizes between 3 and 129 km2. Landuse and surface cover types (share of vegetation, bare soil and rock outcrops) were derived from aerial images by objective classification techniques. Using data from a dense rainfall network we analysed the effects of scale, catchment properties and aridity on runoff generation. Thereby we extracted rainfall and corresponding runoff events from our time-series to calculate event based rainfall characteristics and catchment runoff coefficients. Soil moisture observations provided additional information on antecedent moisture conditions, infiltration characteristics and the evolution of saturated areas. In contrast to the prevailing opinion that the proportion of Hortonian overland flow increases with aridity, we found that in our area the largest share (> 95 %) of runoff is generated by saturation excess overland flow in response to long lasting, rainfall events of high amount. This was supported by a strong correlation between event runoff and precipitation totals. Similar rainfall thresholds (50 mm) for runoff generation were observed in all investigated catchments. No scale effects on runoff coefficients were found; instead we identified up to three-fold runoff coefficients in catchments with larger extension of arid areas, higher percentage of rock outcrops and urbanization. Comparing two headwater catchments with noticeable differences in extent of olive orchards, no difference in runoff generation was

  5. Trend analysis of nutrient loadings in the South Saskatchewan River catchment

    Science.gov (United States)

    Morales-Marin, L. A.; Chun, K. P.; Wheater, H. S.; Lindenschmidt, K. E.

    2015-12-01

    Nutrient loadings in river catchments have increased in the past years as a consequence of rapid expansion of agricultural areas, new urban developments and industries, and population growth. Nutrient enrichment of water bodies has intensified eutrophication conditions that degrade water quality and ecosystem health. In large-scale catchments, the assessment of temporal and spatial variability of nutrient loads imply challenges due to climate, land use and geology heterogeneity, and to anthropogenic changes. In this study we carried out a trend analysis of total phosphorus and total nitrogen loads in the South Saskatchewan River (SSR) catchment. This catchment is located in the Canadian Prairie Provinces of Alberta and Saskatchewan. The eastern and central areas of the catchment consist mostly of croplands, pasture lands and livestock farms, whereas the western parts are located on the Rocky Mountains that are the source of most of the catchment's streamflows. The trend analysis was performed applying a novel approach to analyse nutrient time series recorded at long-term water quality stations along the main stems of the SSR river network. Since water quality is taken infrequently, in the proposed approach the time series were complemented using regression analysis methods based on streamflow data recorded at the nearest gauge stations. The time series were subsequently pre-whitened in order to remove the autocorrelation, and then subjected to non-parametric statistical test to detect trends. Seasonal analysis of trends at each of the water quality stations were performed in order to determine the relationships between annual flow regimes and nutrient loads in the catchment, in particular, the influence of the high spring runoff on nutrient export. Decadal analysis was also performed to determine the long-tern relationships of nutrients with anthropogenic changes in the catchment. In particular, the capacity of reservoirs to trap nutrients and the effects of the

  6. Geochemical insights to the formation of "sedimentary buffers": Considering the role of tributary-trunk stream interactions on catchment-scale sediment flux and drainage network dynamics

    Science.gov (United States)

    Fryirs, Kirstie; Gore, Damian B.

    2014-08-01

    The concept of disconnectivity (or decoupling) of sediment movement in river systems is an important concept in analyses of sediment flux in catchments. At the catchment scale, various blockages-termed buffers, barriers and blankets-form along the sediment cascade, interrupting the conveyance of sediments downstream. Long-lived buffers can control aspects of catchment sediment flux for an extended period. The upper Hunter catchment has a highly disconnected sediment cascade. The most highly disconnected subcatchment (Dart Brook) contains a distinct type of buffer, a trapped tributary fill, in its downstream reaches, reducing the effective catchment area of the upper Hunter catchment by ~ 18%. We test the use of elemental analyses provided by X-ray fluorescence (XRF) spectrometry of homogenous sediment profiles taken from floodplain bank exposures to determine that the geochemical composition of the sediments that make up this trapped-tributary fill system have been derived from two distinct source areas (the tributary system and the trunk stream). Over at least the Holocene, sedimentation along the axis of the Hunter River valley (the trunk stream) has formed an impediment to sediment conveyance along the lower tributary catchment, essentially "trapping" the tributary. We present an evolutionary model of how this type of "blockage" has formed and discuss implications of tributary-trunk stream (dis)connectivity in analysis of catchment-scale sediment flux and drainage network dynamics. In this case, a relatively large tributary network is having a "geomorphically insignificant" impact on trunk stream dynamics.

  7. Impact of spatial and temporal resolution of rainfall inputs on urban hydrodynamic modelling outputs: A multi-catchment investigation

    Science.gov (United States)

    Ochoa-Rodriguez, Susana; Wang, Li-Pen; Gires, Auguste; Pina, Rui Daniel; Reinoso-Rondinel, Ricardo; Bruni, Guendalina; Ichiba, Abdellah; Gaitan, Santiago; Cristiano, Elena; van Assel, Johan; Kroll, Stefan; Murlà-Tuyls, Damian; Tisserand, Bruno; Schertzer, Daniel; Tchiguirinskaia, Ioulia; Onof, Christian; Willems, Patrick; ten Veldhuis, Marie-Claire

    2015-12-01

    Urban catchments are typically characterised by high spatial variability and fast runoff processes resulting in short response times. Hydrological analysis of such catchments requires high resolution precipitation and catchment information to properly represent catchment response. This study investigated the impact of rainfall input resolution on the outputs of detailed hydrodynamic models of seven urban catchments in North-West Europe. The aim was to identify critical rainfall resolutions for urban catchments to properly characterise catchment response. Nine storm events measured by a dual-polarimetric X-band weather radar, located in the Cabauw Experimental Site for Atmospheric Research (CESAR) of the Netherlands, were selected for analysis. Based on the original radar estimates, at 100 m and 1 min resolutions, 15 different combinations of coarser spatial and temporal resolutions, up to 3000 m and 10 min, were generated. These estimates were then applied to the operational semi-distributed hydrodynamic models of the urban catchments, all of which have similar size (between 3 and 8 km2), but different morphological, hydrological and hydraulic characteristics. When doing so, methodologies for standardising model outputs and making results comparable were implemented. Results were analysed in the light of storm and catchment characteristics. Three main features were observed in the results: (1) the impact of rainfall input resolution decreases rapidly as catchment drainage area increases; (2) in general, variations in temporal resolution of rainfall inputs affect hydrodynamic modelling results more strongly than variations in spatial resolution; (3) there is a strong interaction between the spatial and temporal resolution of rainfall input estimates. Based upon these results, methods to quantify the impact of rainfall input resolution as a function of catchment size and spatial-temporal characteristics of storms are proposed and discussed.

  8. Spatial Analysis in Determination Of Flood Prone Areas Using Geographic Information System and Analytical Hierarchy Process at Sungai Sembrong's Catchment

    Science.gov (United States)

    Bukari, S. M.; Ahmad, M. A.; Wai, T. L.; Kaamin, M.; Alimin, N.

    2016-07-01

    Floods that struck Johor state in 2006 and 2007 and the East Coastal in 2014 have triggered a greatly impact to the flood management here in Malaysia. Accordingly, this study conducted to determine potential areas of flooding, especially in Batu Pahat district since it faces terrifying experienced with heavy flood. This objective is archived by using the application of Geographic Information Systems (GIS) on study area of flood risk location at the watershed area of Sungai Sembrong. GIS functions as spatial analysis is capable to produce new information based on analysis of data stored in the system. Meanwhile the Analytical Hierarchy Process (AHP) was used as a method for setting up in decision making concerning the existing data. By using AHP method, preparation and position of the criteria and parameters required in GIS are neater and easier to analyze. Through this study, a flood prone area in the watershed of Sungai Sembrong was identified with the help of GIS and AHP. Analysis was conducted to test two different cell sizes, which are 30 and 5. The analysis of flood prone areas were tested on both cell sizes with two different water levels and the results of the analysis were displayed by GIS. Therefore, the use of AHP and GIS are effective and able to determine the potential flood plain areas in the watershed area of Sungai Sembrong.

  9. Space-time modeling of catchment scale drought characteristics

    NARCIS (Netherlands)

    Tallaksen, L.; Hisdal, H.; Lanen, van H.A.J.

    2009-01-01

    Drought may affect all components of the water cycle and covers commonly a large part of the catchment area. This paper examines drought propagation at the catchment scale using spatially aggregated drought characteristics and illustrates the importance of catchment processes in modifying the drough

  10. The Achievement of a Decentralized Water Management Through Stakeholder Participation: An Example from the Drôme River Catchment Area in France (1981-2008)

    Science.gov (United States)

    Comby, Emeline; Le Lay, Yves-François; Piégay, Hervé

    2014-11-01

    Different water Acts (e.g., the European Water Framework Directive) and stakeholders involved in aquatic affairs have promoted integrated river basin management over recent decades. However, few studies have provided feedback on these policies. The aim of the current article is to fill this gap by exploring how local newspapers reflect the implementation of a broad public participation within a catchment of France known for its innovation with regard to this domain. The media coverage of a water management strategy in the Drôme watershed from 1981 to 2008 was investigated using a content analysis and a geographic information system. We sought to determine what public participation and decentralized decision-making can be in practice. The results showed that this policy was integrated because of its social perspective, the high number of involved stakeholders, the willingness to handle water issues, and the local scale suitable for participation. We emphasized the prominence of the watershed scale guaranteed by the local water authority. This area was also characterized by compromise, arrangements, and power dynamics on a fine scale. We examined the most politically engaged writings regarding water management, which topics of each group emphasized, and how the groups agreed and disagreed on issues based on their values and context. The temporal pattern of participation implementation was progressive but worked by fits and starts.

  11. On the value of combined event runoff and tracer analysis to improve understanding of catchment functioning in a data-scarce semi-arid area

    OpenAIRE

    M. Hrachowitz; Bohte, R.; Mul, M.L.; Bogaard, T.A.; Savenije, H. H. G.; S. Uhlenbrook

    2011-01-01

    Hydrological processes in small catchments are not quite understood yet, which is true in particular for catchments in data scarce, semi-arid regions. This is in contrast with the need for a better understanding of water fluxes and the interactions between surface- and groundwater in order to facilitate sustainable water resources management in such environments, where both floods and droughts can result in severe crop loss. In this study, event runoff coefficient analysis and limited tracer ...

  12. Catchment conceptualisation for examining applicability of chloride mass balance method in an area with historical forest clearance

    OpenAIRE

    H. Guan; Love, A. J.; C. T. Simmons; Hutson, J; Ding, Z

    2010-01-01

    Of the various approaches for estimating groundwater recharge, the chloride mass balance (CMB) method is one of the most frequently used, especially for arid and semiarid regions. Widespread native vegetation clearance, common in many areas globally, has changed the land surface boundary condition, posing the question as to whether the current system has reached new chloride equilibrium, required for a CMB application. Although a one-dimensional CMB can be applied at a point where the water a...

  13. Environmental impacts of incineration of livestock manure with the purpose of energy utilization. Scenario analysis for a specific catchment area; Miljoekonsekvenser ved afbraending af husdyrgoedning med sigte pae energiudnyttelse. Scenarieanalyse for et udvalgt opland

    Energy Technology Data Exchange (ETDEWEB)

    Schou, J.S.; Gyldenkaerne, S.; Levin, G. [DMU, Afd. for Systemanalyse (Denmark); Grant, R. [DMU, Afdeling for Ferskvandsoekologi (Denmark); Elmegaard, N. [DMU, Afdeling for Terrestrisk Oekologi (Denmark); Palmgren, F. [DMU, Afd. for Atmosfaerisk Miljoe (Denmark)

    2006-04-15

    The analyses demonstrate the environmental consequences of incineration of livestock manure in a specific catchment area where an unchanged animal production is presumed. The scenarios are carried out for the Vesthimmerland area, located in the north of the peninsula of Jutland (Denmark) where the agricultural production is characterised by a relatively intensive production of broilers and furred animals. It is assumed that half of the total production of manure from farms with broilers and mink is incinerated on incineration plants on farm level and decentralised CHP plants. This corresponds to an incineration of manure from 1.951 DE (one animal unit corresponds to a production of 100 kg N per year) at which 219 tonnes N, 54 tonnes P and 118 tonnes K are removed, corresponding to 5 % N, 5.5 % P and 3 % K, respectively. The estimated environmental consequences are summarized in Table 19 and the results are commented below. Assuming the effective N content of the incinerated manure is replaced with artificial fertiliser while not compensating for the removed P, it is estimated that the N leaching in the catchment area is reduced by 46.5 tonnes (approx. 2 %) while the P surplus is reduced from 200 tonnes to 146 tonnes (approx. 27 % reduction). Furthermore the incineration of manure will impact the emission of ammonia as the loss from storage and spreading is reduced. Thus there will be a reduction of ammonia emissions from storage facilities by 25.3 tonnes N while the reduction of emission from spreading is estimated to 17.2 tonnes N. All together a reduction of the ammonia emissions of 42.5 tonnes N is thus achieved. Furthermore, analyses of additional deposition of gaseous N compounds, especially N{sub 2}O, NO, NO{sub 2} and N{sub 2} from the air in the area close to an incineration plant have been carried out. The analyses presume that the amount of N emitted from incineration corresponds to the amount of N in manure. The analyses show that if the NO{sub X

  14. The role of climatic and terrain attributes in estimating baseflow recession in tropical catchments

    Directory of Open Access Journals (Sweden)

    J. L. Peña-Arancibia

    2010-11-01

    Full Text Available The understanding of low flows in rivers is paramount more than ever as demand for water increases on a global scale. At the same time, limited streamflow data to investigate this phenomenon, particularly in the tropics, makes the provision of accurate estimations in ungauged areas an ongoing research need. This paper analysed the potential of climatic and terrain attributes of 167 tropical and sub-tropical unregulated catchments to predict baseflow recession rates. Daily streamflow data (m3 s–1 from the Global River Discharge Center (GRDC and a linear reservoir model were used to obtain baseflow recession coefficients (kbf for these catchments. Climatic attributes included annual and seasonal indicators of rainfall and potential evapotranspiration. Terrain attributes included indicators of catchment shape, morphology, land cover, soils and geology. Stepwise regression was used to identify the best predictors for baseflow recession coefficients. Mean annual rainfall (MAR and aridity index (AI were found to explain 49% of the spatial variation of kbf. The rest of climatic indices and the terrain indices average catchment slope (SLO and tree cover were also good predictors, but co-correlated with MAR. Catchment elongation (CE, a measure of catchment shape, was also found to be statistically significant, although weakly correlated. An analysis of clusters of catchments of smaller size, showed that in these areas, presumably with some similarity of soils and geology due to proximity, residuals of the regression could be explained by SLO and CE. The approach used provides a potential alternative for kbf parameterisation in ungauged catchments.

  15. Can the catchment scale SWAT model undertake management at field scale?

    Science.gov (United States)

    Lu, Shenglan; Trolle, Dennis; Blicher-Mathiesen, Gitte; Estrup Andersen, Hans

    2015-04-01

    Nitrate losses from agricultural areas to waterways remain a serious stressor for aquatic ecosystems in many developed countries, despite the fact that decades of water action plans have reduced these losses. More intelligent ways of further reducing nitrate losses are now sought for, particularly the ability to pinpoint the location of critical areas where the potential for nitrate losses are high. Here, mathematical models can play a key role, as they offer the ability to locate areas at various size-discretization, where losses could potentially be high. The Soil and Water Assessment Tool (SWAT) have been widely applied for quantifying nitrate losses from agricultural catchments, but the model have rarely be validated at field scale that are relevant for implementation of management measures, often due to lack of data from such scales. In this study, we calibrated the SWAT model for intensively monitored smaller Danish catchments based only on data from the catchment outlets. We then looked into smaller areas within these catchments and evaluated the SWAT models ability to reproduce observed tile drain dynamics and nitrogen budgets at the field scale, including fertilizer application, crop yields, leaching through the root zone and tile drainage. To evaluate the importance of the simulated tile drainage at larger scales, we applied the SWAT model to a large section of the River Odense catchment in Denmark and analysed the nitrogen sources and budgets.

  16. Compilation of modal analyses of volcanic rocks from the Nevada Test Site area, Nye County, Nevada

    International Nuclear Information System (INIS)

    Volcanic rock samples collected from the Nevada Test Site, Nye County, Nevada, between 1960 and 1985 were analyzed by thin section to obtain petrographic mode data. In order to provide rapid accessibility to the entire database, all data from the cards were entered into a computerized database. This computer format will enable workers involved in stratigraphic studies in the Nevada Test Site area and other locations in southern Nevada to perform independent analyses of the data. The data were compiled from the mode cards into two separate computer files. The first file consists of data collected from core samples taken from drill holes in the Yucca Mountain area. The second group of samples were collected from measured sections and surface mapping traverses in the Nevada Test Site area. Each data file is composed of computer printouts of tables with mode data from thin section point counts, comments on additional data, and location data. Tremendous care was taken in transferring the data from the cards to computer, in order to preserve the original information and interpretations provided by the analyzer. In addition to the data files above, a file is included that consists of Nevada Test Site petrographic data published in other US Geological Survey and Los Alamos National Laboratory reports. These data are presented to supply the user with an essentially complete modal database of samples from the volcanic stratigraphic section in the Nevada Test Site area. 18 refs., 4 figs

  17. 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.

  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. Geochemical and mineralogical composition of bog iron ore as a resource for prehistoric iron production - A case study of the Widawa catchment area in Eastern Silesia, Poland

    Science.gov (United States)

    Thelemann, Michael; Bebermeier, Wiebke; Hoelzmann, Philipp

    2016-04-01

    Spreading from the Near East in the declining Bronze Age from the 2nd millennium BCE onwards, the technique of iron smelting reached Eastern Silesia, Poland, in approximately the 2nd century BCE (pre-Roman Iron Age). At this time the region of the Widawa catchment area was inhabited by the Przeworsk culture. While the older moraine landscape of the study area lacks ores from geological rock formations, bog iron ores were relatively widespread and, due to their comparatively easy accessibility, were commonly exploited for early iron production. In this poster the mineralogical and elemental composition of local bog iron ore deposits and iron slag finds, as a by-product of the smelting process, are investigated. The crystalline mineralogical composition of local bog iron ores is dominated by quartz (SiO2) and goethite (α FeO(OH)), in contrast to slag samples in which fayalite (Fe2SiO4), wüstite (FeO) and quartz, with traces of goethite, represent the main minerals. Ores and slags are both characterized by notable hematite (Fe2O3), magnetite (Fe3O4) and maghemite (γ-Fe2O3) contents. Analyzed bog iron ore samples show iron contents of up to 64.9 mass% Fe2O3 (45.4 mass% Fe), whereas the iron contents of bloomery slags vary between 48.7 and 72.0 mass% FeO (37.9 and 56.0 mass% Fe). A principal component analysis of the element contents, which were quantified by portable energy-dispersive X-ray fluorescence spectrometry (p-ED-XRF), indicates local variations in the elemental composition. Our results show that bog iron ores are relatively widely distributed with spatially varying iron contents along the Widawa floodplain but present-day formation conditions (e.g. different ground-water levels) are negatively affected by modern land-use practices, such as agriculture and melioration measures.

  20. Concentrations of geogenic heavy metals in meadowland sediments and soils in the Saale river catchment area. A contribution to the ecological assessment of heavy metal pollution in bodies of surface water

    International Nuclear Information System (INIS)

    In a joint project covering the main tributaries of the Elbe river, heavy metal concentrations in recent river sediments of the Saale river were measured. Apart from the most relevant pollutants (Cd, Zn, Pb, Cu, Cr, Ni, Hg, As), further metals and Se were also measured. The results provided information on the volumes, distribution, sources and regional distribution of heavy metal pollution as well as on the development of pollution with time since 1991. Natural (geogenic) metal concentrations are an issue as renaturing plans are being developed. In order to avoid unrealistic sanitation goals, an attempt was made to assess the distribution of the geogenic background values of fine-grained river sediments in part catchment areas of a large river catchment area (here: the Saale river) in order to obtain a standard regional geogenic background value for each element

  1. Interannual variability of a precipitation gradient along the semi-arid catchment areas for the metropolitan region of Lima- Peru in relation to atmospheric circulation at the mesoscale

    Science.gov (United States)

    Otto, Marco; Seidel, Jochen; Trachte, Katja

    2013-04-01

    The main moisture source for precipitation on the western slopes of the Central Andes is located east of the mountain range known as the Amazon basin. However, the Andean mountains, which reach up to 6000 m a.s.l., strongly influence climatic conditions along the Pacific coastline of South America as a climatic barrier for the low-level tropospheric flow and associated moisture transport from the Amazon basin. Additional, large scale subsidence caused by the South Pacific High inhabits convective rainfall at the Pacific coast where large metropolitan areas such as the Peruvian capital Lima are located. Two contrasts in precipitation can be found while crossing the Andean mountains from West to East. On the Pacific coast, at the location of the metropolitan area of Lima, no more than 10 mm mean annual rainfall occurs. In contrast, up to 1000 mm mean annual rainfall occur only 100 km east of Lima within the upper region (4000 m .a.s.l.) of the Western Cordillera. The transition takes place along the western slopes of the Western Cordillera and is characterised by a strong precipitation gradient. Here, catchment areas are located that provide most of the water resources needed to sustain an urban area of approximately 10 million people. This study investigates the interannual variability of the precipitation gradient between 1998 and 2012. The analysis is based on daily precipitation data of 22 rain gauge station, daily rainfall data of the Tropical Rainfall Mission (TRMM 3B42) at 0.25 degrees and reanalysis data at 36 km spatial resolution at the mesoscale. The reanalysis data was produced using the Weather Research and Forecasting Model. Station data was provided by the Peruvian weather service during the project "Sustainable Water and Wastewater Management in Urban Growth Centres Coping with Climate Change - Concepts for Lima Metropolitana (Peru) (LiWa)", which is financed by the German Federal Ministry of Education and Research (BMBF). We are interested in the

  2. The chemical behaviour and ecological transfer in human food chain of some radionuclides in aqueous ecosystems and their risk on population health. Part of a coordinated programme on radiological and environmental protection studies in the Danube River catchment area

    International Nuclear Information System (INIS)

    The radioecological concentration of H-3, K-40, Sr-90, Cs-137, and Ra-226 in the Danube River catchment area in Romania as well as the migration of these radionuclides in the food chain was determined. It was found that the concentration of each of these radionuclides in the Danube water was very low and that the radioactivity in the food chain was lower than the maximum permissible level. Very low incidence of cancer was detected among the inhabitants along the river

  3. Biodegradation of free cyanide by bacterial species isolated from cyanide-contaminated artisanal gold mining catchment area in Burkina Faso.

    Science.gov (United States)

    Razanamahandry, Lovasoa Christine; Andrianisa, Harinaivo Anderson; Karoui, Hela; Kouakou, Koffi Marcelin; Yacouba, Hamma

    2016-08-01

    Soil and water samples were collected from a watershed in Burkina Faso where illegal artisanal gold extraction using cyanidation occurs. The samples were used to evaluate cyanide contamination and the presence of cyanide degrading bacteria (CDB). Free cyanide (F-CN) was detected in all samples, with concentrations varying from 0.023 to 0.9 mg kg(-1), and 0.7-23 μg L(-1) in the soil and water samples, respectively. Potential CDB also were present in the samples. To test the effective F-CN degradation capacity of the isolated CDB species, the species were cultivated in growth media containing 40, 60 or 80 mg F-CN L(-1), with or without nutrients, at pH 9.5 and at room temperature. More than 95% of F-CN was degraded within 25 h, and F-CN degradation was associated with bacterial growth and ammonium production. However, initial concentrations of F-CN higher than 100 mg L(-1) inhibited bacterial growth and cyanide degradation. Abiotic tests showed that less than 3% of F-CN was removed by volatilization. Thus, the degradation of F-CN occurred predominately by biological mechanisms, and such mechanisms are recommended for remediation of contaminated soil and water. The bacteria consortium used in the experiment described above exist in a Sahelian climate, which is characterized by a long hot and dry season. Because the bacteria are already adapted to the local climate conditions and show the potential for cyanide biodegradation, further applicability to other contaminated areas in West Africa, where illegal gold cyanidation is widespread, should be explored. PMID:27209555

  4. The hydrological responses of different land cover types in a re-vegetation catchment area of the Loess Plateau, China

    Directory of Open Access Journals (Sweden)

    S. Wang

    2012-05-01

    Full Text Available The impact of re-vegetation on soil moisture dynamics was investigated by comparing five land cover types. Soil moisture and temperature variations under grass (Andropogon, subshrub (Artemisia scoparia, shrub (Spiraea pubescens, tree (Robinia pseudoacacia, and crop (Zea mays vegetation were monitored in an experiment performed during the growing season of 2011. There were more than 10 soil moisture pulses during the period of data collection, and the surface soil moisture of all of the land cover types showed an increasing trend. Corn cover was associated with consistently higher soil moisture readings than the other surfaces. Grass and subshrubs showed an intermediate moisture level, with that of grass being slightly higher than that of subshrub most of the time. Shrubs and trees were characterized by lower soil moisture readings, with the shrub levels consistently being slightly higher than those of the trees. With the exception of the corn land cover type, the average soil temperature showed the same regime as the average moisture content, but exhibiting a downward trend throughout the observation period. Three typical decreasing periods were chosen to compare the differences in water losses. In periods of both relatively lower and higher water soil moisture contents, subshrubs lost the largest amount of water. The daily water loss associated with corn was most variable. The tree and shrub sites presented an intermediate level, with that of tree being slightly higher compared to shrub; the daily water loss trends of these two land cover types were similar and were more stable than those of the other types. The amount of water loss related to the grass land cover type is determined by the initial moisture content. Soil under subshrubs acquired and retained soil moisture resources more efficiently than the other cover types, representing an adaptive vegetation type in this area.

  5. Estimating Catchment-Scale Snowpack Variability in Complex Forested Terrain, Valles Caldera National Preserve, NM

    Science.gov (United States)

    Harpold, A. A.; Brooks, P. D.; Biederman, J. A.; Swetnam, T.

    2011-12-01

    Difficulty estimating snowpack variability across complex forested terrain currently hinders the prediction of water resources in the semi-arid Southwestern U.S. Catchment-scale estimates of snowpack variability are necessary for addressing ecological, hydrological, and water resources issues, but are often interpolated from a small number of point-scale observations. In this study, we used LiDAR-derived distributed datasets to investigate how elevation, aspect, topography, and vegetation interact to control catchment-scale snowpack variability. The study area is the Redondo massif in the Valles Caldera National Preserve, NM, a resurgent dome that varies from 2500 to 3430 m and drains from all aspects. Mean LiDAR-derived snow depths from four catchments (2.2 to 3.4 km^2) draining different aspects of the Redondo massif varied by 30%, despite similar mean elevations and mixed conifer forest cover. To better quantify this variability in snow depths we performed a multiple linear regression (MLR) at a 7.3 by 7.3 km study area (5 x 106 snow depth measurements) comprising the four catchments. The MLR showed that elevation explained 45% of the variability in snow depths across the study area, aspect explained 18% (dominated by N-S aspect), and vegetation 2% (canopy density and height). This linear relationship was not transferable to the catchment-scale however, where additional MLR analyses showed the influence of aspect and elevation differed between the catchments. The strong influence of North-South aspect in most catchments indicated that the solar radiation is an important control on snow depth variability. To explore the role of solar radiation, a model was used to generate winter solar forcing index (SFI) values based on the local and remote topography. The SFI was able to explain a large amount of snow depth variability in areas with similar elevation and aspect. Finally, the SFI was modified to include the effects of shading from vegetation (in and out of

  6. 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)

  7. Assessment of Diversity, Distribution, Conservation Status and Preparation of Management Plan for Medicinal Plants in the Catchment Area of Parbati Hydroelectric Project Stage -Ⅲ in Northwestern Himalaya

    Institute of Scientific and Technical Information of China (English)

    S.S. Samant; Jitendra S. Butola; Aman Sharma

    2007-01-01

    ligulata may be considered as threatened species due to their over exploitation for trade. 90 species are propagated by seeds, 8 species by seeds and rhizomes/roots/tubers,4 species by seeds and cuttings, and 2 species by sori.A management plan for the cultivation and conservation of the medicinal plants in the dam submergence area, and the commercially viable medicinal plants with high value in the catchment area is suggested.

  8. Endangering of the groundwater by acid rain - investigations in the catchment area of a drinking-water gallery of the Wiesbadener Hochtaunus. Pt. 1. Presentation of the investigation area and description of the water section-model

    International Nuclear Information System (INIS)

    A research programme for water- and groundwater-acidification was realized in the catchment-area of the shallow groundwater-gallery ''Kalter Born'', which is part of the public water supply of Wiesbaden. The water chemistry of the sources and galleries shows the strongest acidification in the upper part of the aquifer, whereas the deeper groundwater sections show less acidification symptoms. Therefore the water of the deep gallery ''Kellerskopfstollen'' is nearly free of acidification signs in consequence of its long percolation distance (about 200-300 m) between the infiltration level and the gallery. On the other hand, we get an absolutely acid water with pH-values of about 4 and aluminium-concentrations of about 6 mg/l from the upper sources representing the highest groundwater level in the investigation area. As a whole, the aquifer can at least be separated in 4 levels of well distinguishable acidification rates. An exact analysis of the change of ion-concentrations by the water passage between the different water sections shows, that a considerable part of the acid depositions (H+) is temporarily neutralized by the aluminium puffer close below the infiltration level. So the acid is transported downwards masked as aluminium sulfates. In deeper regions the masked acid is converted and finally neutralized by contact with carbonates. (orig.)

  9. Sensitivity analyses of OH missing sinks over Tokyo metropolitan area in the summer of 2007

    Directory of Open Access Journals (Sweden)

    S. Chatani

    2009-09-01

    Full Text Available OH reactivity is one of key indicators which reflect impacts of photochemical reactions in the atmosphere. An observation campaign has been conducted in the summer of 2007 at the heart of Tokyo metropolitan area to measure OH reactivity. The total OH reactivity measured directly by the laser-induced pump and probe technique was higher than the sum of the OH reactivity calculated from concentrations and reaction rate coefficients of individual species measured in this campaign. And then, three-dimensional air quality simulation has been conducted to evaluate the simulation performance on the total OH reactivity including "missing sinks", which correspond to the difference between the measured and calculated total OH reactivity. The simulated OH reactivity is significantly underestimated because the OH reactivity of volatile organic compounds (VOCs and missing sinks are underestimated. When scaling factors are applied to input emissions and boundary concentrations, a good agreement is observed between the simulated and measured concentrations of VOCs. However, the simulated OH reactivity of missing sinks is still underestimated. Therefore, impacts of unidentified missing sinks are investigated through sensitivity analyses. In the cases that unknown secondary products are assumed to account for unidentified missing sinks, they tend to suppress formation of secondary aerosol components and enhance formation of ozone. In the cases that unidentified primary emitted species are assumed to account for unidentified missing sinks, a variety of impacts may be observed, which could serve as precursors of secondary organic aerosols (SOA and significantly increase SOA formation. Missing sinks are considered to play an important role in the atmosphere over Tokyo metropolitan area.

  10. Sensitivity analyses of OH missing sinks over Tokyo metropolitan area in the summer of 2007

    Directory of Open Access Journals (Sweden)

    K. Ishii

    2009-11-01

    Full Text Available OH reactivity is one of key indicators which reflect impacts of photochemical reactions in the atmosphere. An observation campaign has been conducted in the summer of 2007 at the heart of Tokyo metropolitan area to measure OH reactivity. The total OH reactivity measured directly by the laser-induced pump and probe technique was higher than the sum of the OH reactivity calculated from concentrations and reaction rate coefficients of individual species measured in this campaign. And then, three-dimensional air quality simulation has been conducted to evaluate the simulation performance on the total OH reactivity including "missing sinks", which correspond to the difference between the measured and calculated total OH reactivity. The simulated OH reactivity is significantly underestimated because the OH reactivity of volatile organic compounds (VOCs and missing sinks are underestimated. When scaling factors are applied to input emissions and boundary concentrations, a good agreement is observed between the simulated and measured concentrations of VOCs. However, the simulated OH reactivity of missing sinks is still underestimated. Therefore, impacts of unidentified missing sinks are investigated through sensitivity analyses. In the cases that unknown secondary products are assumed to account for unidentified missing sinks, they tend to suppress formation of secondary aerosol components and enhance formation of ozone. In the cases that unidentified primary emitted species are assumed to account for unidentified missing sinks, a variety of impacts may be observed, which could serve as precursors of secondary organic aerosols (SOA and significantly increase SOA formation. Missing sinks are considered to play an important role in the atmosphere over Tokyo metropolitan area.

  11. Establishing the Ecological Status of Mining-Impacted Freshwaters from Abrud River Catchment Area Using Benthic Diatom Communities (Ros, ia MontanÄă, Romania)

    Science.gov (United States)

    Olenici, Adriana; Baciu, Calin; Momeu, Laura; Cozma, Alexandra; Brahaita, Dorian; Pop, Cristian; Lazar, Laura; Popita, Gabriela; Teodosiu, Gabriela

    2015-04-01

    Keywords: diatom communities, indicator species, mine waters, water quality, Romania. Diatoms are a very distinct group of algae, identifiable under the light microscope by their yellow - brown coloration and by the presence of a thick silica cell wall. The potential for freshwater organisms to reflect changes in environmental conditions was first noted by Kolenati (1848) and Cohn (1853), who observed that biota in polluted waters were different from those in non-polluted situations. Diatoms are widely used to monitor river pollution because they are sensitive to water chemistry, especially to ionic content, pH, dissolved organic matter and nutrients. Wide geographic distribution and well-studied ecology of most diatom species are mentioned as major advantages of using diatoms as indicator organisms. At the same time water quality has begun to deteriorate increasingly, mainly as a result of the physical, chemical and bacteriological alterations, and the aquatic ecosystems are evermore affected by various types of pollution, the anthropic one being almost always included. A good example is Abrud River and its main tributaries (Roșia Montană and surrounding areas, Romania), which has suffered along the years because of the mining waters discharge. In this context, this study presents data on benthic diatom communities from the Abrud River catchment area. Sixteen sites have been sampled seasonal and the best represented diatom genera were Navicula, Nitzschia, Cymbella, Gomphonema, Achnantes, Surirella and Fragilaria. Qualitatively, the number of diatom species exhibited significant variation among sampling sites, also suggesting seasonal dynamics. For instance, in some sampling sites, algal assemblages were absent, as diatom communities were strongly affected by acid mine waters, released from old mining works and waste rocks depots. Some dominant taxa have been observed as well, suggesting critical saprobic levels of the Abrud River and some of its tributaries. The

  12. Runoff generation mechanism at two distinct headwater catchments - isotopic evidence

    Science.gov (United States)

    Dohnal, Michal; Votrubová, Jana; Šanda, Martin; Tesař, Miroslav; Vogel, Tomáš; Dušek, Jaromír

    2016-04-01

    Data from two headwater catchments indicate considerably different runoff formation mechanisms. The contributions of different surface and subsurface runoff mechanisms to the catchment discharge formation at these two small forested headwater catchments are studied with help of the natural isotopic signatures of the observed fluxes. The Uhlirska catchment (1.78 sq. km, Jizera Mts., Czech Republic) is situated in headwater area of Cerna Nisa stream. Deluviofluvial granitic sediments in the valley bottom areas (riparian zones/wetlands) are surrounded by gentle hillslopes with shallow soils developed on crystalline bedrock. The Liz catchment (0.99 sq. km, Bohemian Forest, Czech Republic) belongs to hillslope-type catchments without riparian zones situated in headwater area of Volynka River. The soil at Liz is developed on biotite paragneiss bedrock. Autocorrelation analysis of the measured catchment discharge rates reveals different hydrograph characteristics for each of the two catchments. Estimated autocorrelation lengths differ by an order of magnitude. Variations of oxygen-18 isotope concentrations in precipitation, groundwater and streamflow were analyzed. Several significant rainfall-runoff events at each of the two catchments were analyzed in detail. These events exhibit substantial difference in isotopic compositions of event and pre-event water, which facilitates hydrograph separation. Clockwise and counterclockwise hysteretic relationships between the stream discharge and its isotope concentration were identified. Results were confronted with the previously published concepts of the runoff formation at the catchments under study. The research was funded by the Czech Science Foundation, project No. 14-15201J.

  13. Time series analyses for PM10 and ozone in the Mexico City metropolitan area

    Energy Technology Data Exchange (ETDEWEB)

    Icaza del Rio, G. de; Choularton, T.W.

    1998-12-31

    The Mexico City Metropolitan Area (MCMA) is located in a U shape valley at the foothills of the Anahuac cordilleras. Although situated in the tropical latitudes it has the climate of a temperate urban agglomeration. The topography of the valley is dominated by its high altitude, on the average of 2400 m above the mean sea level (msl), and its surrounding mountains that reach to more than 5300 m above msl. Overall the climate on the valley floor is semiarid with an accumulated annual mean precipitation over the city dropping from about 900 to 400 mm as one travels from west to east while the wet and dry seasons are fairly well defined, April to September and October to March respectively. The annual variation of temperature is relatively small but the diurnal range is large. Because of its geographic location, among other factors, the MCMA suffers from severe pollution problems. The altitude of the valley provides abundant solar radiation and its shape reduces the dispersion capabilities of the basin. Ozone and PM10 have been characterized as two of the most dangerous pollutants, because of both their high concentrations and their inherent chemical composition. Trends of both pollutants are examined for the period 1994-96 and the relation with some of their associated pollutants is analyzed. The results from this study show that the concentration of PM10 has increased in the three years and that the ozone concentrations have decreased slightly over the same period. Furthermore, meteorological parameters are incorporated into the analyses to help explain some of the deviations within the time series.

  14. The effects of land use on runoff and soil nutrient losses in a gully catchment of the hilly areas: implications for erosion control%黄土丘陵小流域土地利用格局对径流与土壤养分流失的影响--土壤侵蚀控制的意义

    Institute of Scientific and Technical Information of China (English)

    王军; 傅伯杰; 邱扬

    2005-01-01

    Serious soil erosion is one of the major issues threatening sustainable land use in semiarid areas, especially in the Loess Plateau of China. Understanding the effects of land use on soil and water loss is important for sustainable land use strategy. Two sub-catchments: catchment A (CA) and catchment B (CB) with distinct land uses were selected to measure soil moisture, runoff and soil nutrient loss in Da Nangou catchment of the Loess Plateau of China. The effects of land use patterns on runoff and nutrient losses were analyzed based on soil moisture pattern by kriging and soil nutrients using multiple regression model. The results indicated that there were significant differences in runoff yield and soil nutrient losses between the two sub-catchments. With similar land uses, the CA produced an average sediment yield of 49 kg ha-1 and 22.27 kg ha-1 during two storm events.Meanwhile, there was almost no runoff in the CB with dissimilar land uses during the same events.Buffer zones should be established to re-absorb runoff and to trap sediments in catchment with similar land use structure such as the CA. Moreover, land use management strategy aiming to increase the infiltration threshold of hydrological response units could decrease the frequency of runoff occurrence on a slope and catchment scale.

  15. Study of 137Cs and 90Sr content in surface and subterranean waters in water catchment areas of polluted territories of near and distant zones of the chernobyl trace

    International Nuclear Information System (INIS)

    At present, the radioecological situation is characterized by the decrease of pollution densities of higher lying water catchment areas and by wash-out of radionuclides to lowlands, bottom lands and deep into the ground. On this account, increase of surface pollution density takes place in lowlands and flood lands. Comparison of the data on ground water from the weels of constant observation in the near zone shows that the content of 137Cs and 90Sr in ground water is lower than that in surface water by 2...15 and 3...90 times, respectively, in observation sites of the near zone it depends on time and place of sampling

  16. Using biophysical models to manage nitrogen pollution from agricultural sources: Utopic or realistic approach for non-scientist users? Case study of a drinking water catchment area in Lorraine, France.

    Science.gov (United States)

    Bernard, Pierre-Yves; Benoît, Marc; Roger-Estrade, Jean; Plantureux, Sylvain

    2016-12-01

    The objectives of this comparison of two biophysical models of nitrogen losses were to evaluate first whether results were similar and second whether both were equally practical for use by non-scientist users. Results were obtained with the crop model STICS and the environmental model AGRIFLUX based on nitrogen loss simulations across a small groundwater catchment area (challenges for non-scientists such as lack of parameter optimization, which is essential to accurately assessing nitrogen fluxes and indirectly not to limit the diversity of uses of simulated results. Despite current restrictions, with some improvement, biophysical models could become useful environmental assessment tools for non-scientists. PMID:27596940

  17. Hydrological dynamics of a Mediterranean catchment in a global change context. (Romanyac catchment, Cap de Creus, Girona, Spain)

    Science.gov (United States)

    Latron, J.; Pardini, G.; Gispert, M.; Llorens, P.

    2009-04-01

    Mediterranean regions are characterized by unevenly distributed water resources, and consequently a more precise knowledge of the main hydrological processes and their variability and changes is crucial for a better management of water resources. However, the lack of hydrological information and data in most areas of the Mediterranean basin greatly difficult the analyses of changes in water resources at relevant scales. In this context, the Soil Science Unit GRCT48 from the University of Girona is conducting an integrated study of hydrological response, soil erosion and soil degradation processes in fragile Mediterranean areas undergoing changes in use and management. The study area is located in the Cap de Creus Peninsula (NE Spain), where land abandonment has been the outstanding characteristic over the last decades. The area is covered by terraced soils, most of them abandoned, and stands for a representative Mediterranean environment. Current land cover is a mosaic of areas with different shrubs according to wildfire occurrence. Residual patches of cork and pine trees are also present as well as small extensions of pastures. Finally some localized areas of vineyards and olive trees are still cultivated. The approach is based on the complementary use of plot and catchment scales to assess the effect of land cover and land use change on physical, chemical and biological parameters of soil quality and on rainfall-runoff-erosion relationships. Along the study period, observed rainfall-runoff response at the plot scale was highly variable among sites but also for a given environment, depending on antecedent wetness conditions and rainfall characteristics. Overall, surface runoff responses were low in all environments. Soil loss associated to rainfall-runoff events showed very large variations among sites, and also for a given site, between the different rainfall events. At the catchment scale, preliminary results obtained from the monitoring, of three catchments of

  18. Groundwater as an emergency source for drought mitigation in the Crocodile River catchment, South Africa

    Science.gov (United States)

    Mussá, F. E. F.; Zhou, Y.; Maskey, S.; Masih, I.; Uhlenbrook, S.

    2015-02-01

    Global climate change has received much attention worldwide in the scientific as well as in the political community, indicating that changes in precipitation, extreme droughts and floods may increasingly threaten many regions. Drought is a natural phenomenon that causes social, economical and environmental damage to society. In this study, we assess the drought intensity and severity and the groundwater potential to be used as a supplementary source of water to mitigate drought impacts in the Crocodile River catchment, a water-stressed sub-catchment of the Incomati River catchment in South Africa. The research methodology consists of three parts. First, the spatial and temporal variation of the meteorological and hydrological drought severity and intensity over the catchment were evaluated. The Standardized Precipitation Index (SPI) was used to analyse the meteorological drought and the Standardized Runoff Index (SRI) was used for the hydrological drought. Second, the water deficit in the catchment during the drought period was computed using a simple water balance method. Finally, a groundwater model was constructed in order to assess the feasibility of using groundwater as an emergency source for drought impact mitigation. Results show that the low-rainfall areas are more vulnerable to severe meteorological droughts (lower and upper crocodile). Moreover, the most water stressed sub-catchments with high level of water uses but limited storage, such as the Kaap located in the middle catchment and the Lower Crocodile sub-catchments, are more vulnerable to severe hydrological droughts. The analysis of the potential groundwater use during droughts showed that a deficit of 97 Mm3 yr-1 could be supplied from groundwater without considerable adverse impacts on the river base flow and groundwater storage. Abstraction simulations for different scenarios of extremely severe droughts reveal that it is possible to use groundwater to cope with the droughts in the catchment

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

    Science.gov (United States)

    Stoelzle, Michael; Weiler, Markus

    2016-04-01

    Alpine catchments are often considered as quickly responding systems where streamflow contributions from subsurface storages (groundwater) are mostly negligible due to the steep topography, low permeable bedrock and the absence of well-developed soils. Many studies in high altitude catchments have hence focused on water stored in snowpack and glaciers or on rainfall-runoff processes as the dominant streamflow contributions. Interestingly less effort has been devoted to winter streamflow analysis when melt- or rainfall-driven contributions are switched off due to the frozen state of the catchment. Considering projected changes in the alpine cryosphere (e.g. snow, glacier, permafrost) quantification of groundwater storage and contribution to streamflow is crucial to assess the social and ecological implications for downstream areas (e.g. water temperature, drought propagation). In this study we hypothesize that groundwater is the main streamflow contribution during winter and thus being responsible for the perennial regime of many alpine catchments. The hypothesis is investigated with well-known methods based on recession and breakpoint analysis of the streamflow regimes and temperature data to determine frozen periods. Analyzing nine catchments in Switzerland with mean elevation between 1000 and 2400 m asl, we found that above a mean elevation of 1800 m asl winter recessions are sufficient long and persistent enough to quantify groundwater contribution to streamflow and to characterize the properties of subsurface storage. The results show that groundwater in alpine catchment is the dominant streamflow contribution for nearly half a year and accountable for several hundred millimeter of annual streamflow. In sub-alpine catchments, driven by a mix of snowmelt and rainfall, a clear quantification of groundwater contributions is rather challenging due to discontinuous frozen periods in winter. We found that the inter-annual variability of different streamflow

  20. Extended principle component analysis - a useful tool to understand processes governing water quality at catchment scales

    Science.gov (United States)

    Selle, B.; Schwientek, M.

    2012-04-01

    Water quality of ground and surface waters in catchments is typically driven by many complex and interacting processes. While small scale processes are often studied in great detail, their relevance and interplay at catchment scales remain often poorly understood. For many catchments, extensive monitoring data on water quality have been collected for different purposes. These heterogeneous data sets contain valuable information on catchment scale processes but are rarely analysed using integrated methods. Principle component analysis (PCA) has previously been applied to this kind of data sets. However, a detailed analysis of scores, which are an important result of a PCA, is often missing. Mathematically, PCA expresses measured variables on water quality, e.g. nitrate concentrations, as linear combination of independent, not directly observable key processes. These computed key processes are represented by principle components. Their scores are interpretable as process intensities which vary in space and time. Subsequently, scores can be correlated with other key variables and catchment characteristics, such as water travel times and land use that were not considered in PCA. This detailed analysis of scores represents an extension of the commonly applied PCA which could considerably improve the understanding of processes governing water quality at catchment scales. In this study, we investigated the 170 km2 Ammer catchment in SW Germany which is characterised by an above average proportion of agricultural (71%) and urban (17%) areas. The Ammer River is mainly fed by karstic springs. For PCA, we separately analysed concentrations from (a) surface waters of the Ammer River and its tributaries, (b) spring waters from the main aquifers and (c) deep groundwater from production wells. This analysis was extended by a detailed analysis of scores. We analysed measured concentrations on major ions and selected organic micropollutants. Additionally, redox-sensitive variables

  1. 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

  2. Migration to Nonmetropolitan Areas: Appraising the Trend and Reasons for Moving. Special Demographic Analyses.

    Science.gov (United States)

    Long, Larry H.; DeAre, Diana

    An unexpected demographic development in the United States in the 1970's was the shift of nonmetropolitan areas to net inmigration, reversing a 70-year trend. Using the 1970 definition of metropolitan, the percent of the population living in metropolitan areas fell from 69% in 1970 to 67.8% in 1978. No easily identifiable set of reasons explained…

  3. Vulnerability of the karst area related to potentially toxic elements

    OpenAIRE

    Fajković, Hana; Hasan, Ozren; Miko, Slobodan; Juračić, Mladen; Mesić, Saša; Prohić, Esad

    2011-01-01

    Soil samples from 31 locations in the Una river spring catchment were subject to chemical extraction analyses. The data were presented as distribution maps of potentially toxic elements (Al, Cu, Mn, Pb and Zn) in the surface soil of the area. To evaluate the vulnerability of the immediate spring zone of the karst catchment, the vulnerability map was derived from the application of the PI methodology proposed by the European COST Action 620. The PI method used to produce the vulnerability map ...

  4. Suspended sediment apportionment in a South-Korean mountain catchment

    Science.gov (United States)

    Birkholz, Axel; Meusburger, Katrin; Park, Ji-Hyung; Alewell, Christine

    2016-04-01

    Due to the rapid agricultural expansion and intensification during the last decades in South-Korea, large areas of hill slope forests were transformed to paddies and vegetable fields. The intensive agriculture and the easily erodible soils in our catchment are a major reason for the increased erosion causing suspended sediments to infiltrate into the close drinking water reservoir. The drinking water reservoir Lake Soyang provides water supply for over ten million people in Seoul. Landscape managers need to know the exact origin of these sediments before they can create landscape amelioration schemes. We applied a compound-specific stable isotope (CSSI) approach (Alewell et al., 2015) to apportion the sources of the suspended sediments between forest and agricultural soil contribution to the suspended sediments in a different catchment and applied the same approach to identify and quantify the different sources of the suspended sediments in the river(s) contributing to Lake Soyang. We sampled eight soil sites within the catchment considering the different landuse types forest, rice paddies, maize and vegetables. Suspended sediments were sampled at three outlets of the different sub-catchments. Soils and suspended sediments are analysed for bulk carbon and nitrogen isotopes, compound-specific carbon isotopes of plant-wax derived long-chain fatty acids and long-chain n-alkanes. Fatty acid and alkane isotopes are then used in mixing calculations and the mixing model software IsoSource to find out the contribution of the different source soils to the suspended sediments. We present first data of the source soils and the suspended sediments. C. Alewell, A. Birkholz, K. Meusburger, Y. Schindler-Wildhaber, L. Mabit, 2015. Sediment source attribution from multiple land use systems with CSIA. Biogeosciences Discuss. 12: 14245-14269.

  5. Hydrogeochemical signatures of catchment evolution - the role of calcium and sulphate release in the constructed Hühnerwasser ("Chicken Creek") catchment

    Science.gov (United States)

    Pohle, Ina; Hu, Yuzhu; Schaaf, Wolfgang; Gerwin, Werner; Hinz, Christoph

    2016-04-01

    The constructed Hühnerwasser ("Chicken Creek") catchment is an ecohydrological system in an initial state of development. The catchment with an area of 6 ha was built up from quaternary sediments in the post-mining landscape of Lusatia in Eastern Germany and serves as a critical zone observatory for detecting ecosystem transition. The soil substrate is characterized as sands to loamy sands with low carbonate contents but significant amounts of gypsum in the sediments of the catchment. The catchment undergoes a strong transition from an abiotic system in the initial years to a system with growing influence of biota. Concerning the hydrology, a regime shift from surface runoff to groundwater flow dominated processes is significant. It is of interest, whether the catchment transition is also reflected by hydrogeochemical indicators. We assume gypsum dissolution as dominant process at the catchment scale. In order to investigate the hydrogeochemical evolution of the catchment we analysed electric conductivity, calcium and sulphate concentrations and pH-values of biweekly composite samples from 2007-2013 of the atmospheric deposition, of runoff and soil water. The two observation points in the flowing water represent surface runoff and groundwater discharge respectively. Soil water has been analysed at four soil pits in three depths. The monitoring data were provided by the Research Platform Chicken Creek (https://www.tu-cottbus.de/projekte/en/oekosysteme/startseite.html). From the macroscopic data analysis we found an exponential decay of the electric conductivity, calcium and sulphate concentrations in the flowing waters and some of the soil pits. In the flowing water, the decrease slope of the electric conductivity and the calcium and sulphate concentrations is almost identical. The calcium / sulphate molar ratio as an indicator of gypsum dissolution is almost equal to one up to 2010, afterwards more calcium than sulphate is released. The pH-values in the flowing

  6. Oil samples and geochemical analyses of Afghanistan and adjacent areas (oilafg.shp)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This shapefile contains points that describe the location of oil samples collected in Afghanistan and adjacent areas, and the results of organic geochemical analysis.

  7. 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

  8. 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

  9. Thermal Analyses of Apollo Lunar Soils Provide Evidence for Water in Permanently Shadowed Areas

    Science.gov (United States)

    Cooper, Bonnie L.; Smith, M. C.; Gibson, E. K.

    2011-01-01

    Thermally-evolved-gas analyses were performed on the Apollo lunar soils shortly after their return to Earth [1-8]. The analyses revealed the presence of water evolving at temperatures above 200 C. Of particular interest are samples that were collected from permanently-shadowed locations (e.g., under a boulder) with a second sample collected in nearby sunlight, and pairs in which one was taken from the top of a trench, and the second was taken at the base of the trench, where the temperature would have been -10 to -20 C prior to the disturbance [9]. These samples include 63340/63500, 69941/69961, and 76240/76280. At the time that this research was first reported, the idea of hydrated minerals on the lunar surface was somewhat novel. Nevertheless, goethite was observed in lunar breccias from Apollo 14 [10], and it was shown that goethite, hematite and magnetite could originate in an equilibrium assemblage of lunar rocks

  10. Analyzing catchment behavior through catchment modeling in the Gilgel Abay, Upper Blue Nile River Basin, Ethiopia

    Directory of Open Access Journals (Sweden)

    S. Uhlenbrook

    2010-10-01

    model runs per catchment representation explained the different hydrologic responses of the two sub-catchments, which seems to be mainly caused by the presence of dambos in Koga sub-catchment. It is concluded that daily model transferability is not feasible, while it can produce acceptable results for the 15 and 30 days models. This is very useful for water resources planning and management, but not sufficient to capture detailed hydrological processes in an ungauged area.

  11. 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)

  12. Role of glaciers in watershed hydrology: a preliminary study of a "Himalayan catchment"

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    R. J. Thayyen

    2010-02-01

    Full Text Available A large number of Himalayan glacier catchments are under the influence of humid climate with snowfall in winter (November–April and south-west monsoon in summer (June–September dominating the regional hydrology. Such catchments are defined as "Himalayan catchment", where the glacier meltwater contributes to the river flow during the period of annual high flows produced by the monsoon. The winter snow dominated Alpine catchments of the Kashmir and Karakoram region and cold-arid regions of the Ladakh mountain range are the other major glacio-hydrological regimes identified in the region. Factors influencing the river flow variations in a "Himalayan catchment" were studied in a micro-scale glacier catchment in the Garhwal Himalaya, covering an area of 77.8 km2. Three hydrometric stations were established at different altitudes along the Din Gad stream and discharge was monitored during the summer ablation period from 1998 to 2004, with an exception in 2002. These data have been analysed along with winter/summer precipitation, temperature and mass balance data of the Dokriani glacier to study the role of glacier and precipitation in determining runoff variations along the stream continuum from the glacier snout to 2360 m a.s.l. The study shows that the inter-annual runoff variation in a "Himalayan catchment" is linked with precipitation rather than mass balance changes of the glacier. This study also indicates that the warming induced an initial increase of glacier runoff and subsequent decline as suggested by the IPCC (2007 is restricted to the glacier degradation-derived component in a precipitation dominant Himalayan catchment and cannot be translated as river flow response. The preliminary assessment suggests that the "Himalayan catchment" could experience higher river flows and positive glacier mass balance regime together in association with strong monsoon. The important role of glaciers in this precipitation dominant system is

  13. Role of glaciers in watershed hydrology: ''Himalayan catchment'' perspective

    Directory of Open Access Journals (Sweden)

    R. J. Thayyen

    2009-07-01

    Full Text Available A large number of Himalayan glacier catchments are under the influence of humid climate with snowfall in winter (November–April and South-West monsoon in summer (June–September dominating the regional hydrology. Such catchments are defined as ''Himalayan catchment'', where the glacier melt water contributes to the river flow during the period of annual high flows produced by the monsoon. Other two major glacio-hydrological regimes of the Himalaya are winter snow dominated Alpine catchments of the Kashmir and Karakoram region and cold-arid regions of the Ladakh mountain range. Factors influencing the river flow variations in a ''Himalayan catchment'' were studied in a micro scale glacier catchment in the Garhwal Himalaya, covering an area of 77.8 km2. Discharge data generated from three hydrometric stations established at different altitudes of the Din Gad stream during the summer ablation period of 1998, 1999, 2000, 2001, 2003 and 2004. These data has been analysed along with winter/summer precipitation, temperature and mass balance data of the Dokriani glacier to study the role of the glacier and precipitation in determining the runoff variations along the stream continuum from the glacier snout to 2360 m a.s.l. Study shows that the inter-annual runoff variations in a ''Himalayan glacier catchment'' is directly linked with the precipitation rather than mass balance changes of the glacier. Study suggest that warming induced initial increase of glacier degraded runoff and subsequent decline is a glaciers mass balance response and cannot be translated as river flow response in a ''Himalayan catchment'' as suggested by the IPCC, 2007. Study also suggest that the glacier runoff critically influence the headwater river flows during the years of low summer discharge and proposes that the Himalayan catchment could experience higher river flows and positive

  14. Sub-daily variability of suspended sediment fluxes in small mountainous catchments – implications for community-based river monitoring

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    O. Navratil

    2010-10-01

    Full Text Available Accurate estimates of suspended sediment yields depend on effective monitoring strategies. In mountainous environments undergoing intense seasonal precipitation, the implementation of such monitoring programs relies primarily on a rigorous study of the temporal variability of fine sediment transport. This investigation focuses on seasonal and short-term sediment variability in a subhumid region of the Mexican Volcanic Belt. Intensive hydrosedimentary monitoring was conducted during one year on four contrasting catchments (3 to 630 km2. Analyses revealed significant temporal variability in suspended sediment export over various time scales, with between 63 and 97% of the annual load exported in as little as 2% of the time. Statistical techniques were used to evaluate the sampling frequency required to get reliable annual sediment yield estimates at the four sites. A bi-daily sampling would be required at the outlet of the 630-km2 catchment, whereas in the three smaller catchments (3–12 km2, the achievement of accurate estimates would inevitably require hourly monitoring. At the larger catchment scale, analysis of the sub-daily variability of fine sediment fluxes showed that the frequency of sampling could be lowered by up to 100% (i.e. from bi-daily to daily if considering a specific and regular sampling time in the day. In contrast, conducting a similar sampling strategy at the three smaller catchments could lead to serious misinterpretation (i.e. up to 1000% error. Our findings emphasise the importance of an analysis of the sub-daily variability of sediment fluxes in mountainous catchments. Characterising this variability may offer useful insights for improving the effectiveness of community-based monitoring strategies in rural areas of developing countries. In regions where historical records based on discrete sampling are available, it may also help assessing the quality of past flux estimates. Finally, the study confirms the global

  15. Regional lead isotope study of a polluted river catchment: River Wear, Northern England, UK

    Energy Technology Data Exchange (ETDEWEB)

    Shepherd, Thomas J., E-mail: shepherdtj@aol.com [Department of Earth Sciences, University of Durham, Science Laboratories, Durham DH1 3LE (United Kingdom); Chenery, Simon R.N. [British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG (United Kingdom); Pashley, Vanessa [NERC Isotope Geosciences Laboratory, Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG (United Kingdom); Lord, Richard A. [School of Science and Technology, University of Teesside, Middlesbrough, Tees Valley TS1 3BA (United Kingdom); Ander, Louise E.; Breward, Neil; Hobbs, Susan F. [British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG (United Kingdom); Horstwood, Matthew [NERC Isotope Geosciences Laboratory, Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG (United Kingdom); Klinck, Benjamin A. [British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG (United Kingdom); Worrall, Fred [Department of Earth Sciences, University of Durham, Science Laboratories, Durham DH1 3LE (United Kingdom)

    2009-08-15

    High precision, lead isotope analyses of archived stream sediments from the River Wear catchment, northeast England (1986-88), provide evidence for three main sources of anthropogenic lead pollution; lead mining, industrial lead emissions and leaded petrol. In the upper catchment, pollution is totally controlled and dominated by large lead discharges from historic mining centres in the North Pennine Orefield ({sup 208}Pb/{sup 206}Pb, {sup 207}Pb/{sup 206}Pb ratios range from 2.0744-2.0954 and 0.8413-0.8554 respectively). In the lower catchment, co-extensive with the Durham Coalfield and areas of high population density, pollution levels are lower and regionally more uniform. Isotope ratios are systematically higher than in the upper catchment ({sup 208}Pb/{sup 206}Pb, {sup 207}Pb/{sup 206}Pb ratios range from 2.0856-2.1397 and 0.8554-0.8896 respectively) and far exceed values determined for the geogenic regional background. Here, the pollution is characterised by the atmospheric deposition of industrial lead and petrol lead. Lead derived from the combustion of coal, although present, is masked by the other two sources. Recent sediments from the main channel of the River Wear are isotopically indistinguishable from older, low order stream sediments of the North Pennine Orefield, indicating that contamination of the river by lead mining waste (up to several 1000 mg/kg Pb at some locations) continues to pose an environmental problem; a pattern that can be traced all the way to the tidal reach. Using within-catchment isotope variation and sediment lead concentrations, estimates can be made of the discharges from discrete mines or groups of mines to the overall level of lead pollution in the River Wear. As well as providing information pertinent to source apportionment and on-going catchment remediation measures, the database is a valuable resource for epidemiologists concerned with the health risks posed by environmental lead.

  16. Regional lead isotope study of a polluted river catchment: River Wear, Northern England, UK

    International Nuclear Information System (INIS)

    High precision, lead isotope analyses of archived stream sediments from the River Wear catchment, northeast England (1986-88), provide evidence for three main sources of anthropogenic lead pollution; lead mining, industrial lead emissions and leaded petrol. In the upper catchment, pollution is totally controlled and dominated by large lead discharges from historic mining centres in the North Pennine Orefield (208Pb/206Pb, 207Pb/206Pb ratios range from 2.0744-2.0954 and 0.8413-0.8554 respectively). In the lower catchment, co-extensive with the Durham Coalfield and areas of high population density, pollution levels are lower and regionally more uniform. Isotope ratios are systematically higher than in the upper catchment (208Pb/206Pb, 207Pb/206Pb ratios range from 2.0856-2.1397 and 0.8554-0.8896 respectively) and far exceed values determined for the geogenic regional background. Here, the pollution is characterised by the atmospheric deposition of industrial lead and petrol lead. Lead derived from the combustion of coal, although present, is masked by the other two sources. Recent sediments from the main channel of the River Wear are isotopically indistinguishable from older, low order stream sediments of the North Pennine Orefield, indicating that contamination of the river by lead mining waste (up to several 1000 mg/kg Pb at some locations) continues to pose an environmental problem; a pattern that can be traced all the way to the tidal reach. Using within-catchment isotope variation and sediment lead concentrations, estimates can be made of the discharges from discrete mines or groups of mines to the overall level of lead pollution in the River Wear. As well as providing information pertinent to source apportionment and on-going catchment remediation measures, the database is a valuable resource for epidemiologists concerned with the health risks posed by environmental lead.

  17. A participatory approach for Integrated River Basin Management in the Elbe catchment

    Science.gov (United States)

    Nunneri, C.; Hofmann, J.

    2005-02-01

    This paper presents a qualitative analysis of a series of in-depth interviews with governmental and non-governmental institutions (NGOs). Within the EUROCAT 1 project this methodology of participatory approach, aiming to scope the present perceptions about environmental issues and possible strategies for environmental improvement, is applied to the study of the Elbe catchment for the first time. In this frame, an Advisory Board (AB) was created, with the aim of giving insights into conflicting interests in the river catchment and guidelines for river basin management. Focus of the Elbe case study is the issue of nutrient enrichment (from the catchment) and the induced eutrophication of the coastal waters (the German Bight). Specifically, regarding this topic, the possible reduction of eutrophication in the German Bight by a (policy driven) decrease in nutrient inputs from the catchment area is analysed. Different measures for reducing the input of nutrients from the catchment, and ultimately preventing eutrophication of the coastal waters are considered. In this context, the members of the AB were asked about the efficiency and feasibility of different measures and the criteria for choosing 'better' management solutions among the possible ones. Although there is a general agreement about the necessity of reducing nutrient emissions, some members of the AB perceive other environmental issues (e.g. altered morphodynamics) as more relevant than nutrient enrichment. Voluntary cooperation, eco-efficiency and 'trans-sectoral' communication are the key concepts mentioned as being indispensable for integrated management. The (public) acceptance of measures for nutrient reduction have to find its way through compromises and social equity, allowing for win-win solutions among different groups of interests and balanced spatial division of costs and benefits. EUROpean CATchments, Project N° EVK1-CT-2000-00044 ( http://www.iia-cnr.unical.it/EUROCAT/project.htm).

  18. Controls on Water Storage, Mixing and Release in a Nested Catchment Set-up with Clean and Mixed Physiographic Characteristics

    Science.gov (United States)

    Pfister, L.; McDonnell, J.; Hissler, C.; Martínez-Carreras, N.; Klaus, J.

    2015-12-01

    With catchment water storage being only rarely determined, storage dynamics remain largely unknown to date. However, storage bears considerable potential for catchment inter-comparison exercises, as well as it is likely to have an important role in regulating catchment functions. Catchment comparisons across a wide range of environments and scales will help to increase our understanding of relationships between storage dynamics and catchment processes. With respect to the potential of catchment storage for bringing new momentum to catchment classification and catchment processes understanding we currently investigate spatial and temporal variability of dynamic storage in a nested catchment set-up (16 catchments) of the Alzette River basin (Luxembourg, Europe), covering a wide range of geological settings, catchment areas, contrasted landuse, and hydro-meteorological and tracer series. We define catchment storage as the total amount of water stored in a control volume, delimited by the catchment's topographical boundaries and depth of saturated and unsaturated zones. Complementary storage assessments (via input-output dynamics of natural tracers, geographical sounding, groundwater level measurements, soil moisture measurements, hydrometry) are carried out for comparison purposes. In our nested catchment set-up we have (1) assessed dependencies between geology, catchment permeability and winter runoff coefficients, (2) calculated water balance derived catchment storage and mixing potential and quantified how dynamic storage differs between catchments and scales, and (3) examined how stream baseflow dD (as a proxy for baseflow transit time) and integrated flow measures (like the flow duration curve) relate to bedrock geology. Catchments with higher bedrock permeability exhibited larger storage capacities and eventually lower average winter runoff coefficients. Over a time-span of 11 years, all catchments re-produced the same winter runoff coefficients year after year

  19. 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

  20. 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.

  1. Stakeholder discourse and water management in a catchment in northern Italy

    Directory of Open Access Journals (Sweden)

    P. S. Lupo Stanghellini

    2007-06-01

    Full Text Available The Water Framework Directive (WFD; directive 2000/60/EC was created to ensure the sustainable use of water resources in the European Union. A central guideline included throughout the directive is a call for the participation of stakeholders in the management of these resources. Involving stakeholders is an important step to ensure that catchment management plans take into consideration local experience in the development of these plans and the impact of the plans on local interests. This paper describes and analyses the results of a series of workshops to facilitate implementation of the WFD at a catchment level based on the stakeholder participation model, CATCH.

    To test the usefulness of the stakeholder participation model CATCH for water management in a catchment area, a sub-catchment in an alpine valley in the north-east of Italy, the Alta Valsugana in the Province of Trento, was chosen as the setting for a series of workshops. In this valley water is fundamental for activities associated with agriculture, domestic use, energy production, sports and recreation. In the recent past the valley has had serious problems related to water quality and quantity. Implementation of water management plans under the WFD may lead to conflicts within the catchment between different stakeholder interest groups. Including stakeholders in the development of management plans not only follows the guidelines of the WFD but also could result in a more locally adapted and acceptable plan for the catchment.

    A new stakeholder analysis methodology was developed and implemented in order to identify the relevant stakeholders of the area and then two sets of workshops involving the key stakeholders identified were conducted in Spring 2006. The CATCH meetings were a new experience for the participants, who had to deal with both the principles of the WFD in general and the participation requirement in particular. During the meetings, the CATCH model

  2. Methodology for Definition of Yellow Fever Priority Areas, Based on Environmental Variables and Multiple Correspondence Analyses

    OpenAIRE

    Eduardo Stramandinoli Moreno; Rita de Cássia Barradas Barata

    2012-01-01

    Yellow fever (YF) is endemic in much of Brazil, where cases of the disease are reported every year. Since 2008, outbreaks of the disease have occurred in regions of the country where no reports had been registered for decades, which has obligated public health authorities to redefine risk areas for the disease. The aim of the present study was to propose a methodology of environmental risk analysis for defining priority municipalities for YF vaccination, using as example, the State of São Pau...

  3. Mitochondrial DNA analyses reveal low genetic diversity in Culex quinquefasciatus from residential areas in Malaysia.

    Science.gov (United States)

    Low, V L; Lim, P E; Chen, C D; Lim, Y A L; Tan, T K; Norma-Rashid, Y; Lee, H L; Sofian-Azirun, M

    2014-06-01

    The present study explored the intraspecific genetic diversity, dispersal patterns and phylogeographic relationships of Culex quinquefasciatus Say (Diptera: Culicidae) in Malaysia using reference data available in GenBank in order to reveal this species' phylogenetic relationships. A statistical parsimony network of 70 taxa aligned as 624 characters of the cytochrome c oxidase subunit I (COI) gene and 685 characters of the cytochrome c oxidase subunit II (COII) gene revealed three haplotypes (A1-A3) and four haplotypes (B1-B4), respectively. The concatenated sequences of both COI and COII genes with a total of 1309 characters revealed seven haplotypes (AB1-AB7). Analysis using tcs indicated that haplotype AB1 was the common ancestor and the most widespread haplotype in Malaysia. The genetic distance based on concatenated sequences of both COI and COII genes ranged from 0.00076 to 0.00229. Sequence alignment of Cx. quinquefasciatus from Malaysia and other countries revealed four haplotypes (AA1-AA4) by the COI gene and nine haplotypes (BB1-BB9) by the COII gene. Phylogenetic analyses demonstrated that Malaysian Cx. quinquefasciatus share the same genetic lineage as East African and Asian Cx. quinquefasciatus. This study has inferred the genetic lineages, dispersal patterns and hypothetical ancestral genotypes of Cx. quinquefasciatus.

  4. Geochemical Analyses in Mineral Deposits “ Çikatova e Vjeter” in Drenas Area-Kosovo

    Directory of Open Access Journals (Sweden)

    Afrim Koliqi

    2016-06-01

    Full Text Available Mineral deposit Çikatova e Vjeter consists of two ore bodies that are laterites process iron-nickel products of weathering crust developed in ultrabasic rocks. Dushkaja ore body present Nicel-Iron silicate product of weathering crust coverage primary type formed up serpentenites. Ore body Suka is typical resedimentation Quaternary deposits of Iron- Nickel laterite consists of four lentils with irregular shapes unrelated to each other and is located south of Dushkaja distance of 800 m. Studies have determined different vertical zonality in weathering crust of ore body Dushkaja and Suka which are separate zones with geochemical characteristics. Content of nickel in ore body “Suka” compared with Ni in Dushkaja not show any significant poorer. Mineral deposits Cikatova e Vjeter is locating in Drenas region Kosovo territory. The paper aims thanks of metalogeny analyse to clarify and define the main geology conditions nickel ore forming deposits in time and space in the territory of Kosovo and defining criteria for research and finding of new metalogeny units with ironnickel ore.

  5. Climatic and Catchment-Scale Predictors of Chinese Stream Insect Richness Differ between Taxonomic Groups.

    Science.gov (United States)

    Tonkin, Jonathan D; Shah, Deep Narayan; Kuemmerlen, Mathias; Li, Fengqing; Cai, Qinghua; Haase, Peter; Jähnig, Sonja C

    2015-01-01

    Little work has been done on large-scale patterns of stream insect richness in China. We explored the influence of climatic and catchment-scale factors on stream insect (Ephemeroptera, Plecoptera, Trichoptera; EPT) richness across mid-latitude China. We assessed the predictive ability of climatic, catchment land cover and physical structure variables on genus richness of EPT, both individually and combined, in 80 mid-latitude Chinese streams, spanning a 3899-m altitudinal gradient. We performed analyses using boosted regression trees and explored the nature of their influence on richness patterns. The relative importance of climate, land cover, and physical factors on stream insect richness varied considerably between the three orders, and while important for Ephemeroptera and Plecoptera, latitude did not improve model fit for any of the groups. EPT richness was linked with areas comprising high forest cover, elevation and slope, large catchments and low temperatures. Ephemeroptera favoured areas with high forest cover, medium-to-large catchment sizes, high temperature seasonality, and low potential evapotranspiration. Plecoptera richness was linked with low temperature seasonality and annual mean, and high slope, elevation and warm-season rainfall. Finally, Trichoptera favoured high elevation areas, with high forest cover, and low mean annual temperature, seasonality and aridity. Our findings highlight the variable role that catchment land cover, physical properties and climatic influences have on stream insect richness. This is one of the first studies of its kind in Chinese streams, thus we set the scene for more in-depth assessments of stream insect richness across broader spatial scales in China, but stress the importance of improving data availability and consistency through time.

  6. Highly resolved reconstruction of the continental development of climate and environment during the time period of the Funnel Beaker Culture in catchment areas of lakes; Hochaufloesende Rekonstruktion der kontinentalen Klima- und Umweltentwicklung waehrend der Trichterbecherzeit in Seeeinzugsgebieten

    Energy Technology Data Exchange (ETDEWEB)

    Zahrer, Juergen

    2012-07-01

    The research has long been concerned with the identification of the past climatic changes. In the course of the actual public discussion on the interactions between anthropogenic activities and the environmental changes, these investigations experienced a strong revival in the past decades. Under this aspect, the author of the contribution under consideration investigates the impact of the climatic conditions on the development of the Funnel Beaker Culture and especially on the agricultural land use in this cultural period. The author tries to answer the following key questions: (a) Do the investigated sequences of sediment contain evidences for synchronous changes in connection with the climatic changes?; (b) Are there also differences in the land use of the catchment areas in view of the point in time of landscape dissemination as well as the duration and intensity of the neolithic land use?.

  7. Maintenance Plan for the Performance Assessments and Composite Analyses of the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site

    International Nuclear Information System (INIS)

    U.S. Department of Energy (DOE) Manual M 435.1-1 requires that performance assessments (PAs) and composite analyses (CAs) for low-level waste (LLW) disposal facilities be maintained by the field offices. This plan describes the activities performed to maintain the PA and the CA for the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) at the Nevada Test Site (NTS). This plan supersedes the Maintenance Plan for the Performance Assessments and Composite Analyses for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site (DOE/NV/11718--491-REV 1, dated September 2002). The plan is based on U.S. Department of Energy (DOE) Order 435.1 (DOE, 1999a), DOE Manual M 435.1-1 (DOE, 1999b), the DOE M 435.1-1 Implementation Guide DOE G 435.1-1 (DOE, 1999c), and the Maintenance Guide for PAs and CAs (DOE, 1999d). The plan includes a current update on PA/CA documentation, a revised schedule, and a section on Quality Assurance

  8. Coverage of Adequately Iodized Salt Is Suboptimal and Rice Fortification Using Public Distribution Channels Could Reach Low-Income Households: Findings from a Cross-Sectional Survey of Anganwadi Center Catchment Areas in Telangana, India.

    Science.gov (United States)

    Wirth, James P; Leyvraz, Magali; Sodani, Prahlad R; Aaron, Grant J; Sharma, Narottam D; Woodruff, Bradley A

    2016-01-01

    Food fortification is a cost-effective approach to prevent and control of micronutrient deficiencies in India. A cross-sectional survey of children 0-35 months of age residing in the catchment areas of anganwadi centers in the state of Telangana was conducted to assess the coverage of adequately iodized salt and the potential for rice fortification. Salt samples were collected and tested for iodine concentration using iodometric titration. Information on demographics, household rice consumption, and Telangana's rice sector was collected and interpreted. In households of selected children, 79% of salt samples were found to be adequately iodized. Salt brand and district were significant predictors of inadequately iodized salt. Daily rice consumption among children and women averaged 122 grams and 321 grams per day, respectively. Approximately 28% of households reported consuming rice produced themselves or purchased from a local farmer, 65% purchased rice from a market or shop, 6% got rice from a public distribution system site, and 2% obtained it from a rice mill. In the catchment areas of Telangana's anganwadi centers, there is significant variation in the coverage of adequately iodized salt by district. Future surveys in Telangana should measure the coverage of salt iodization in the general population using quantitative methods. Nonetheless, increasing the adequacy of iodization of smaller salt manufacturers would help achieve universal salt iodization in Telangana. Despite high consumption of rice, our findings suggest that large-scale market-based rice fortification is not feasible in Telangana due to a large proportion of households producing their own rice and highly fragmented rice distribution. Distributing fortified rice via Telangana's public distribution system may be a viable approach to target low-income households, but would only reach a small proportion of the population in Telangana.

  9. Coverage of Adequately Iodized Salt Is Suboptimal and Rice Fortification Using Public Distribution Channels Could Reach Low-Income Households: Findings from a Cross-Sectional Survey of Anganwadi Center Catchment Areas in Telangana, India.

    Science.gov (United States)

    Wirth, James P; Leyvraz, Magali; Sodani, Prahlad R; Aaron, Grant J; Sharma, Narottam D; Woodruff, Bradley A

    2016-01-01

    Food fortification is a cost-effective approach to prevent and control of micronutrient deficiencies in India. A cross-sectional survey of children 0-35 months of age residing in the catchment areas of anganwadi centers in the state of Telangana was conducted to assess the coverage of adequately iodized salt and the potential for rice fortification. Salt samples were collected and tested for iodine concentration using iodometric titration. Information on demographics, household rice consumption, and Telangana's rice sector was collected and interpreted. In households of selected children, 79% of salt samples were found to be adequately iodized. Salt brand and district were significant predictors of inadequately iodized salt. Daily rice consumption among children and women averaged 122 grams and 321 grams per day, respectively. Approximately 28% of households reported consuming rice produced themselves or purchased from a local farmer, 65% purchased rice from a market or shop, 6% got rice from a public distribution system site, and 2% obtained it from a rice mill. In the catchment areas of Telangana's anganwadi centers, there is significant variation in the coverage of adequately iodized salt by district. Future surveys in Telangana should measure the coverage of salt iodization in the general population using quantitative methods. Nonetheless, increasing the adequacy of iodization of smaller salt manufacturers would help achieve universal salt iodization in Telangana. Despite high consumption of rice, our findings suggest that large-scale market-based rice fortification is not feasible in Telangana due to a large proportion of households producing their own rice and highly fragmented rice distribution. Distributing fortified rice via Telangana's public distribution system may be a viable approach to target low-income households, but would only reach a small proportion of the population in Telangana. PMID:27447925

  10. Coverage of Adequately Iodized Salt Is Suboptimal and Rice Fortification Using Public Distribution Channels Could Reach Low-Income Households: Findings from a Cross-Sectional Survey of Anganwadi Center Catchment Areas in Telangana, India.

    Directory of Open Access Journals (Sweden)

    James P Wirth

    Full Text Available Food fortification is a cost-effective approach to prevent and control of micronutrient deficiencies in India. A cross-sectional survey of children 0-35 months of age residing in the catchment areas of anganwadi centers in the state of Telangana was conducted to assess the coverage of adequately iodized salt and the potential for rice fortification. Salt samples were collected and tested for iodine concentration using iodometric titration. Information on demographics, household rice consumption, and Telangana's rice sector was collected and interpreted. In households of selected children, 79% of salt samples were found to be adequately iodized. Salt brand and district were significant predictors of inadequately iodized salt. Daily rice consumption among children and women averaged 122 grams and 321 grams per day, respectively. Approximately 28% of households reported consuming rice produced themselves or purchased from a local farmer, 65% purchased rice from a market or shop, 6% got rice from a public distribution system site, and 2% obtained it from a rice mill. In the catchment areas of Telangana's anganwadi centers, there is significant variation in the coverage of adequately iodized salt by district. Future surveys in Telangana should measure the coverage of salt iodization in the general population using quantitative methods. Nonetheless, increasing the adequacy of iodization of smaller salt manufacturers would help achieve universal salt iodization in Telangana. Despite high consumption of rice, our findings suggest that large-scale market-based rice fortification is not feasible in Telangana due to a large proportion of households producing their own rice and highly fragmented rice distribution. Distributing fortified rice via Telangana's public distribution system may be a viable approach to target low-income households, but would only reach a small proportion of the population in Telangana.

  11. Coverage of Adequately Iodized Salt Is Suboptimal and Rice Fortification Using Public Distribution Channels Could Reach Low-Income Households: Findings from a Cross-Sectional Survey of Anganwadi Center Catchment Areas in Telangana, India

    Science.gov (United States)

    Wirth, James P.; Leyvraz, Magali; Sodani, Prahlad R.; Aaron, Grant J.; Sharma, Narottam D.; Woodruff, Bradley A.

    2016-01-01

    Food fortification is a cost-effective approach to prevent and control of micronutrient deficiencies in India. A cross-sectional survey of children 0–35 months of age residing in the catchment areas of anganwadi centers in the state of Telangana was conducted to assess the coverage of adequately iodized salt and the potential for rice fortification. Salt samples were collected and tested for iodine concentration using iodometric titration. Information on demographics, household rice consumption, and Telangana’s rice sector was collected and interpreted. In households of selected children, 79% of salt samples were found to be adequately iodized. Salt brand and district were significant predictors of inadequately iodized salt. Daily rice consumption among children and women averaged 122 grams and 321 grams per day, respectively. Approximately 28% of households reported consuming rice produced themselves or purchased from a local farmer, 65% purchased rice from a market or shop, 6% got rice from a public distribution system site, and 2% obtained it from a rice mill. In the catchment areas of Telangana’s anganwadi centers, there is significant variation in the coverage of adequately iodized salt by district. Future surveys in Telangana should measure the coverage of salt iodization in the general population using quantitative methods. Nonetheless, increasing the adequacy of iodization of smaller salt manufacturers would help achieve universal salt iodization in Telangana. Despite high consumption of rice, our findings suggest that large-scale market-based rice fortification is not feasible in Telangana due to a large proportion of households producing their own rice and highly fragmented rice distribution. Distributing fortified rice via Telangana’s public distribution system may be a viable approach to target low-income households, but would only reach a small proportion of the population in Telangana. PMID:27447925

  12. Methodology for definition of yellow fever priority areas, based on environmental variables and multiple correspondence analyses.

    Science.gov (United States)

    Moreno, Eduardo Stramandinoli; Barata, Rita de Cássia Barradas

    2012-01-01

    Yellow fever (YF) is endemic in much of Brazil, where cases of the disease are reported every year. Since 2008, outbreaks of the disease have occurred in regions of the country where no reports had been registered for decades, which has obligated public health authorities to redefine risk areas for the disease. The aim of the present study was to propose a methodology of environmental risk analysis for defining priority municipalities for YF vaccination, using as example, the State of São Paulo, Brazil. The municipalities were divided into two groups (affected and unaffected by YF) and compared based on environmental parameters related to the disease's eco-epidemiology. Bivariate analysis was used to identify statistically significant associations between the variables and virus circulation. Multiple correspondence analysis (MCA) was used to evaluate the relationship among the variables and their contribution to the dynamics of YF in Sao Paulo. The MCA generated a factor that was able to differentiate between affected and unaffected municipalities and was used to determine risk levels. This methodology can be replicated in other regions, standardized, and adapted to each context.

  13. Methodology for definition of yellow fever priority areas, based on environmental variables and multiple correspondence analyses.

    Directory of Open Access Journals (Sweden)

    Eduardo Stramandinoli Moreno

    Full Text Available Yellow fever (YF is endemic in much of Brazil, where cases of the disease are reported every year. Since 2008, outbreaks of the disease have occurred in regions of the country where no reports had been registered for decades, which has obligated public health authorities to redefine risk areas for the disease. The aim of the present study was to propose a methodology of environmental risk analysis for defining priority municipalities for YF vaccination, using as example, the State of São Paulo, Brazil. The municipalities were divided into two groups (affected and unaffected by YF and compared based on environmental parameters related to the disease's eco-epidemiology. Bivariate analysis was used to identify statistically significant associations between the variables and virus circulation. Multiple correspondence analysis (MCA was used to evaluate the relationship among the variables and their contribution to the dynamics of YF in Sao Paulo. The MCA generated a factor that was able to differentiate between affected and unaffected municipalities and was used to determine risk levels. This methodology can be replicated in other regions, standardized, and adapted to each context.

  14. Chemical, molecular, and proteomic analyses of moss bag biomonitoring in a petrochemical area of Sardinia (Italy).

    Science.gov (United States)

    Cortis, Pierluigi; Vannini, Candida; Cogoni, Annalena; De Mattia, Fabrizio; Bracale, Marcella; Mezzasalma, Valerio; Labra, Massimo

    2016-02-01

    In this study, Hypnum cupressiforme moss bags were used to examine the atmospheric deposition of trace elements in the oil refinery region of Sardinia (Italy) compared with surrounding natural zones. The concentrations of 13 elements [arsenic (As), calcium (Ca), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), sodium (Na), nickel (Ni), lead (Pb), vanadium (V), and zinc (Zn)] were determined using inductively coupled plasma optical emission spectrometry. A significant accumulation of pollutants was detected using active biomonitoring with moss bags compared with a control site. The most relevant contaminants for all of the tested sites were Cr, Cu, Ni, and Zn. Moreover, the accumulation of Cr and Zn in the refinery industrial areas, IA1 and IA2, was more than five times greater than that detected at the control site. Levels of Cd, Mg, and Pb were also higher at all of the monitored sites compared with the control site. Both genomic and proteomic methods were used to study the response of H. cupressiforme to air pollution. No DNA damage or mutations were detected using the amplified fragment length polymorphisms (AFLP) method. At the protein level, 15 gel spots exhibited differential expression profiles between the moss samples collected at the IA1 site and the control site. Furthermore, among the 14 spots that showed a decrease in protein expression, nine were associated with ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) and proteins of the light-harvesting complexes of photosystem (PS) II, three were associated with protein synthesis, and three were stress-related proteins. Thus, some of these proteins may represent good moss biosensors which could be used as pre-alert markers of environmental pollution. PMID:26408120

  15. Relations between topography, wetlands, vegetation cover and stream water chemistry in boreal headwater catchments in Sweden

    Directory of Open Access Journals (Sweden)

    J.-O. Andersson

    2008-05-01

    Full Text Available A large part of the spatial variation of stream water chemistry is found in headwater streams and small catchments. To understand the dominant processes, taking place in small and heterogeneous catchments, spatial and temporal data with high resolution is needed. In most cases available map data has too low quality and resolution to successfully be used in environmental assessments and modelling. In this study 18 forested catchments (1–4 km2 were selected within a 120×50 km area in the county of Värmland in western Sweden. The aim was to test if topographic and vegetation variables derived from official datasets were correlated to stream water chemistry, represented by DOC, Al, Fe and Si content. A GIS was used to analyse the elevation characteristics, generate topographic indices and calculate the percentage of wetlands and a number of vegetation classes. The results clearly show that the topography has a major influence on the occurrence of wetlands, which has a major influence on stream water chemistry. There were very strong correlations between mean slope and percentage wetland, percentage wetland and DOC, mean slope and DOC and mean topographic wetness index and DOC. The conclusion was that official topographic data, despite uncertain or low quality and resolution, could be useful in the prediction of headwater chemistry in boreal forested catchments.

  16. Refinement and evaluation of crack-opening-area analyses for circumferential through-wall cracks in pipes

    International Nuclear Information System (INIS)

    Leak-before-break (LBB) analyses for circumferentially cracked pipes are currently being conducted in the nuclear industry to justify elimination of pipe whip restraints and jet impingement shields which are present because of the expected dynamic effects from pipe rupture. The application of the LBB methodology frequently requires calculation of leak rates. These leak rates depend on the crack-opening area of a through-wall crack in the pipe. In addition to LBB analyses, which assume a hypothetical flaw size, there is also interest in the integrity of actual leaking cracks corresponding to current leakage detection requirements in NRC Regulatory Guide 1.45, or for assessing temporary repair of Class 2 and 3 pipes that have leaks as are being evaluated in ASME Section 11. This study was requested by the NRC to review, evaluate, and refine current analytical models for crack-opening-area analyses of pipes with circumferential through-wall cracks. Twenty-five pipe experiments were analyzed to determine the accuracy of the predictive models. Several practical aspects of crack-opening such as; crack-face pressure, off-center cracks, restraint of pressure-induced bending, cracks in thickness transition regions, weld residual stresses, crack-morphology models, and thermal-hydraulic analysis, were also investigated. 140 refs., 105 figs., 41 tabs

  17. Temporal variability of surface runoff due to cropping systems in cultivated catchment areas: Use of the DIAR model for the assessment of environmental public policies in the Pays de Caux (France).

    Science.gov (United States)

    Martin, P; Joannon, A; Piskiewicz, N

    2010-01-01

    This article proposes the use of a new model, DIAR (Diagnostic Agronomique du Ruissellement, or Agronomic Assessment of Runoff), for the prediction of the timing of the risk of runoff. DIAR is dedicated to loamy soils which are very sensitive to surface crusting, leading to runoff, soil erosion and muddy flows. The approach is proposed for the north-western European loess belt regions where muddy flows severely impact human activities. The likelihood of runoff is assessed from the sequence of soil surface states generated by cultivation practices. DIAR is based on the calculation of curve number values, for each stage of the soil-surface-state sequence, for calculating runoff for each of these stages. In this study, DIAR is applied to a catchment of 912 ha, cultivated by 26 farmers in the Pays de Caux (Normandy, France) where infrastructures located at the outlet have been damaged several times by muddy flows. Local public authorities involved in reducing muddy flows are eager to limit the agricultural upstream runoff by extending the planting of mustard as a winter cover crop. We tested the efficiency of such a policy on the reduction of the mean runoff. We also tested the year-to-year variability of this efficiency using the acreages of four successive years (1999-2000 to 2002-2003). Finally, the cost-efficiency of the policy was also considered. Though we used the same weather scenario, the initial situation (without much mustard cover) showed a wide year-to-year variation in the total runoff. This variation can be associated with the structure of the farms that cultivate the catchment (Utilised Agricultural Area (UAA) of each farm and percentage of this UAA inside the catchment). Our results showed that the widespread planting of winter cover crops could reduce the runoff by 10-20% compared with the initial situation (depending on the year), and also reduce the year-to-year variability of runoff. For each of the 4 tested years, the cost of the infiltrated m(3

  18. Catchment scale multi-objective flood management

    Science.gov (United States)

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

    2010-05-01

    techniques will include: controlling headwater drainage, increasing evapotranspiration and interception by creating new woodlands in the upper catchment areas, enabling coarse woody debris dams to slow down water flows through steep valleys, improving soil water storage potential by appropriate soil and crop management, retaining water on lowland flood meadows and wet woodland creation within the floodplain. The project, due to run from 2009 until 2013, incorporates hydrometric and water quality monitoring, together with hydrologic and hydraulic modelling in order to attempt to demonstrate the effect of land management changes on flood dynamics and flood risk management. To date, the project team have undertaken the fundamental catchment characterisation work to understand its physical setting and the interaction of the physical processes that influence the hydrological response of the catchment to incident precipitation. The results of this initial work has led to the identification of a suitably robust hydrometric monitoring network within the catchments to meet the needs of providing both quantitative evidence of the impacts of land management change on flood risk, together with generating good quality datasets for the validation and testing of the new hydrologic models. As the project aims to demonstrate ‘best practice' in all areas, the opportunity has been taken to install a network of automatic hydrometric monitoring equipment, together with an associated telemetry system, in order to maximise data coverage, accuracy and reliability. Good quality datasets are a critical requirement for reliable modelling. The modelling will also be expanded to incorporate climate change scenarios. This paper will describe the catchment characterisation work undertaken to date, the proposed land management changes in relation to flood risk management, the initial catchment hydraulic modelling work and the implementation of the new hydrometric monitoring network within the study area.

  19. Seasonal and spatial variability of {sup 210}Po, {sup 238}U and {sup 239+240}Pu levels in the river catchment area assessed by application of neural-network based classification

    Energy Technology Data Exchange (ETDEWEB)

    Skwarzec, Bogdan [University of Gdansk, Faculty of Chemistry, Chair of Analytical Chemistry, 18/19 Sobieskiego Street, 80-952 Gdansk (Poland)], E-mail: bosk@chem.univ.gda.pl; Kabat, Krzysztof [University of Gdansk, Faculty of Chemistry, Chair of Analytical Chemistry, 18/19 Sobieskiego Street, 80-952 Gdansk (Poland); Astel, Aleksander [Pomeranian Academy, Biology and Environmental Protection Institute, Environmental Chemistry Research Unit, 22a Arciszewskiego Street, 76-200 Slupsk (Poland)

    2009-02-15

    The present study deals with the application of self-organizing maps (SOM) in order to model, classify and interpret seasonal and spatial variability of {sup 210}Po, {sup 238}U and {sup 239+240}Pu levels in the Vistula river basin. The data set represents concentration values for 3 alpha emitters ({sup 210}Po, {sup 238}U and {sup 239+240}Pu) measured in surface water samples collected at 19 different sampling locations (8 in major Vistula stream while 11 in right or left Vistula tributaries) during four seasons (winter, spring, summer and autumn) in the framework of a one-year quality monitoring study. The advantages of an SOM algorithm, its classification and visualization ability for environmental data sets, are stressed. The neural-network based classification made it possible to reveal specific patterns related to both seasonal and spatial variability. In the middle and upper part of Vistula catchment as well as in the right-shore tributaries, concentrations of {sup 210}Po and {sup 238}U during summer and winter are the lowest. Concentrations of {sup 210}Po and {sup 238}U increase significantly during spring and autumn in the Vistula river catchment, especially in the delta of Vistula river. High concentration of anthropogenic originated {sup 239+240}Pu indicates 'site-specific' character of pollution in two large left-shore tributaries located in the middle part of the Vistula drainage area. Efficient classification of sampling locations could lead to an optimization of river radiochemical sampling networks and to a better tracing of natural and anthropogenic changes along Vistula river stream.

  20. 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...

  1. Catchments characterization by means of lumped conceptual models - a case study.

    Science.gov (United States)

    Ley, Rita; Casper, Markus C.

    2016-04-01

    relationship, does not exist for these catchments. All types of catchments occur among neighbored or even nested catchments and show no clear correlation to mean catchment properties. Types a) to c) define catchment characteristics other than usually used properties like catchment area, climate or landscape description. Results show, that these characteristics are crucial for all modelling exercises, model structure selection, understanding, predicting and characterizing the hydrologic behavior of meso-scale catchments.

  2. Calculating ellipse area by the Monte Carlo method and analysing dice poker with Excel at high school

    Science.gov (United States)

    Benacka, Jan

    2016-08-01

    This paper reports on lessons in which 18-19 years old high school students modelled random processes with Excel. In the first lesson, 26 students formulated a hypothesis on the area of ellipse by using the analogy between the areas of circle, square and rectangle. They verified the hypothesis by the Monte Carlo method with a spreadsheet model developed in the lesson. In the second lesson, 27 students analysed the dice poker game. First, they calculated the probability of the hands by combinatorial formulae. Then, they verified the result with a spreadsheet model developed in the lesson. The students were given a questionnaire to find out if they found the lesson interesting and contributing to their mathematical and technological knowledge.

  3. 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

  4. Winter climate affects long-term trends in stream water nitrate in acid-sensitive catchments in southern Norway

    Directory of Open Access Journals (Sweden)

    H. A. de Wit

    2008-03-01

    Full Text Available Controls of stream water NO3 in mountainous and forested catchments are not thoroughly understood. Long-term trends in stream water NO3 are positive, neutral and negative, often apparently independent of trends in N deposition. Here, time series of NO3 in four small acid-sensitive catchments in southern Norway were analysed in order to identify likely drivers of long-term changes in NO3. In two sites, stream water NO3 export declined ca 50% over a period of 25 years while in the other sites NO3 export increased with roughly 20%. Discharge and N deposition alone were poor predictors of these trends. The most distinct trends in NO3 were found in winter and spring. Empirical models explained between 45% and 61% of the variation in weekly concentrations of NO3, and described both upward and downward seasonal trends tolerably well. Key explaining variables were snow depth, discharge, temperature and N deposition. All catchments showed reductions in snow depth and increases in winter discharge. In two inland catchments, located in moderate N deposition areas, these climatic changes appeared to drive the distinct decreases in winter and spring concentrations and fluxes of NO3. In a coast-near mountainous catchment in a low N deposition area, these climatic changes appeared to have the opposite effect, i.e. lead to increases in especially winter NO3. This suggests that the effect of a reduced snow pack may result in both decreased and increased catchment N leaching depending on interactions with N deposition, soil temperature regime and winter discharge.

  5. Winter climate affects long-term trends in stream water nitrate in acid-sensitive catchments in southern Norway

    Directory of Open Access Journals (Sweden)

    H. A. de Wit

    2007-09-01

    Full Text Available Controls of stream water NO3 in mountainous and forested catchments are not thoroughly understood. Long-term trends in stream water NO3 are positive, neutral and negative, often apparently independent of trends in N deposition. Here, time series of NO3 in four small acid-sensitive catchments in southern Norway were analysed in order to identify likely drivers of long-term changes in NO3. In two sites, stream water NO3 export declined ca 50% over a period of 25 years while in the other sites NO3 export increased with roughly 20%. Discharge and N deposition alone were poor predictors of these trends. The most distinct trends in NO3 were found in winter and spring. Empirical models explained between 45% and 61% of the variation in weekly concentrations of NO3, and described both upward and downward seasonal trends tolerably well. Key explaining variables were snow depth, discharge, temperature and N deposition. All catchments showed reductions in snow depth and increases in winter discharge. In two inland catchments, located in moderate N deposition areas, these climatic changes appeared to drive the distinct decreases in winter and spring concentrations and fluxes of NO3. In a coast-near mountainous catchment in a low N deposition area, these climatic changes appeared to have the opposite effect, i.e. lead to increases in especially winter NO3. This suggests that the effect of a reduced snow pack may result in both decreased and increased catchment N leaching depending on interactions with N deposition, soil temperature regime and winter discharge.

  6. Spatializing Area-Based Measures of Neighborhood Characteristics for Multilevel Regression Analyses: An Areal Median Filtering Approach.

    Science.gov (United States)

    Oka, Masayoshi; Wong, David W S

    2016-06-01

    Area-based measures of neighborhood characteristics simply derived from enumeration units (e.g., census tracts or block groups) ignore the potential of spatial spillover effects, and thus incorporating such measures into multilevel regression models may underestimate the neighborhood effects on health. To overcome this limitation, we describe the concept and method of areal median filtering to spatialize area-based measures of neighborhood characteristics for multilevel regression analyses. The areal median filtering approach provides a means to specify or formulate "neighborhoods" as meaningful geographic entities by removing enumeration unit boundaries as the absolute barriers and by pooling information from the neighboring enumeration units. This spatializing process takes into account for the potential of spatial spillover effects and also converts aspatial measures of neighborhood characteristics into spatial measures. From a conceptual and methodological standpoint, incorporating the derived spatial measures into multilevel regression analyses allows us to more accurately examine the relationships between neighborhood characteristics and health. To promote and set the stage for informative research in the future, we provide a few important conceptual and methodological remarks, and discuss possible applications, inherent limitations, and practical solutions for using the areal median filtering approach in the study of neighborhood effects on health.

  7. Remote sensing and GIS analyses for emergency manouvering and forced landing areas definition as a support for general aviation flights

    Science.gov (United States)

    Skocki, Krzysztof

    2016-08-01

    This paper summarizes the preliminary analyses of using existing remote sensing data, medium and high-resolution satellite and airborne data to define safe emergency landing and maneuvering areas to be used by small aircrafts operating from small airports and airfields in Poland. The pilots need to know such places in the interest of safe flight operations. In common practice, flying instructors typically show the student pilot fields around the airfield supposed to be suitable for emergency or precautionary landing (or ditching) in the initial phase of the training. Although it looks to cover the most basic needs, the problem still exists in relation to guest pilots. To fill this gap, the unified safety map document covering the safe emergency areas around the airfields is proposed in this research. Use of satellite high resolution data, as well as aerial photos, infrastructure information, with use of GIS tools (like buffer zones, distance, equal-time circles or position lines) enable to check the terrain around selected airfields and define possible areas suitable for emergency operations. In the second phase of work, selected areas will be described in terms of easy navigation, possible infrastructure around them, rescue possibilities, radio signal coverage, and others. The selected areas should be also checked for typical cover and surface hardness and stability (eg. with use of moisture estimation on the base of middle-resolution satellite data). Its planned to prepare one combined and separate sheets of the final map for various aircraft characteristics (`classes' of small Cessna-related, big Cessna-related, fast low-wing Diamond-like, two-engine Piper-like). The presented concept should highly increase the safety operations for small aviation in secondary airports and airfields, where the information available is limited. There is also a possibility to make a similar maps for `cruise', which means the areas with dense traffic between the airports/airfields.

  8. Trends in the chemistry of atmospheric deposition and surface waters in the Lake Maggiore catchment

    Directory of Open Access Journals (Sweden)

    M. Rogora

    2001-01-01

    Full Text Available The Lake Maggiore catchment is the area of Italy most affected by acid deposition. Trend analysis was performed on long-term (15-30 years series of chemical analyses of atmospheric deposition, four small rivers draining forested catchments and four high mountain lakes. An improvement in the quality of atmospheric deposition was detected, due to decreasing sulphate concentration and increasing pH. Similar trends were also found in high mountain lakes and in small rivers. Atmospheric deposition, however, is still providing a large and steady flux of nitrogen compounds (nitrate and ammonium which is causing increasing nitrogen saturation in forest ecosystems and increasing nitrate levels in rivers. Besides atmospheric deposition, an important factor controlling water acidification and recovery is the weathering of rocks and soils which may be influenced by climate warming. A further factor is the episodic deposition of Saharan calcareous dust which contributes significantly to base cation deposition. Keywords: trend, atmospheric deposition, nitrogen, stream water chemistry.

  9. 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...

  10. How old is upland catchment water?

    Science.gov (United States)

    Hofmann, Harald; Cartwright, Ian; Morgenstern, Uwe; Gilfedder, Benjamin

    2014-05-01

    Understanding the dynamics of water supply catchments is an essential part of water management. Upland catchments provide a continuous, reliable source of high quality water not only for some of the world's biggest cities, but also for agriculture and industry. Headwater streams control river flow in lowland agricultural basins as the majority of river discharge emerges from upland catchments. Many rivers are perennial and flow throughout the year, even during droughts. However, it is still unclear how reliable and continuous upland catchment water resources really are. Despite many efforts in upland catchment research, there is still little known about where the water is stored and how long it takes to travel through upper catchments. Resolving these questions is crucial to ensure that this resource is protected from changing land use and to estimate potential impacts from a changing climate. Previous research in this important area has been limited by existing measurement techniques. Knowledge to date has relied heavily on the use of variation in stable isotope signals to estimate the age and origin of water from upland catchments. The problem with relying on these measures is that as the water residence time increases, the variation in the stable isotope signal decreases. After a maximum period of four years, no variation can be detected This means that to date, the residence time in upland catchments is likely to have been vastly underestimated. Consequently, the proportion of water flow out of upland river catchments to the total river flow is also underestimated. Tritium (3H) combines directly with water molecules and enters the flow paths with the infiltrating water. Its half-life (12.32 years) makes it ideal to describe residence times in upper catchment reservoirs as it can theoretically measure water up to about 150 years old. The bomb pulse peak in the southern hemisphere was several orders of magnitude lower than in the northern hemisphere. Hence the

  11. 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.

  12. Flow path and travel time dynamics in a lowland catchment.

    Science.gov (United States)

    van der Velde, Ype; de Rooij, Gerrit

    2016-04-01

    The distribution of time it takes water from the moment of precipitation to reach the catchment outlet is widely used as a characteristic for catchment flow path contributions, catchment vulnerability to pollution spreading and pollutant loads from catchments to downstream waters. However, this distribution tends to vary in time driven by variability in precipitation and evapotranspiration. Catchment scale mixing of water controls how dynamics in rainfall and evapotranspiration are translated into dynamics of travel time distributions. In this presentation we use the concept of StorAge selection (SAS) functions, that quantify catchment scale mixing of water, to describe chloride and nitrate flow. We will show how SAS functions relate to the topography and subsurface and how they are effective in describing nitrate and chloride transport. The presented analyses will combine unique datasets of high-frequency discharge and water quality concentrations with conceptual models of water flow and solute transport. Remarkable findings are the large contrasts in travel times between lowland and sloping catchments and the strong relationship between evapotranspiration and stream water nutrient concentration dynamics.

  13. A review of sediment and nutrient concentration data from Australia for use in catchment water quality models.

    Science.gov (United States)

    Bartley, Rebecca; Speirs, William J; Ellis, Tim W; Waters, David K

    2012-01-01

    Land use (and land management) change is seen as the primary factor responsible for changes in sediment and nutrient delivery to water bodies. Understanding how sediment and nutrient (or constituent) concentrations vary with land use is critical to understanding the current and future impact of land use change on aquatic ecosystems. Access to appropriate land-use based water quality data is also important for calculating reliable load estimates using water quality models. This study collated published and unpublished runoff, constituent concentration and load data for Australian catchments. Water quality data for total suspended sediments (TSS), total nitrogen (TN) and total phosphorus (TP) were collated from runoff events with a focus on catchment areas that have a single or majority of the contributing area under one land use. Where possible, information on the dissolved forms of nutrients were also collated. For each data point, information was included on the site location, land use type and condition, contributing catchment area, runoff, laboratory analyses, the number of samples collected over the hydrograph and the mean constituent concentration calculation method. A total of ∼750 entries were recorded from 514 different geographical sites covering 13 different land uses. We found that the nutrient concentrations collected using "grab" sampling (without a well defined hydrograph) were lower than for sites with gauged auto-samplers although this data set was small and no statistical analysis could be undertaken. There was no statistically significant difference (p90% of the catchment was represented by a single land use, compared to sites with DON) and dissolved organic phosphorus (DOP). Urban land use had the highest concentrations of dissolved inorganic phosphorus (DIP). This study provides modellers and catchment managers with an increased understanding of the processes involved in estimating constituent concentrations, the data available for use in

  14. Catchment-based landscape patterns and divisions in mountain areas:A case study of Qixia City in Shandong Province%基于流域的山区景观格局分析和分区研究

    Institute of Scientific and Technical Information of China (English)

    曹瑞娜; 齐伟; 李乐; 蒋文惠; 曹向生

    2014-01-01

    This paper used Qixia City (which lies in the center of Jiaodong Peninsula) as a case study of typical mountain areas to investigate catchment-based landscape pattern divisions with cluster analysis of landscape indices generated from digital elevation model (DEM). Firstly, Landsat TM image (2010) covering the whole study area was interpreted and geo-referenced to generate the landscape patterns in Qixia City and the corresponding relief map (1︰25 000) vectorized to build DEM model. Then 300 catchments were divided using hydrology extension support in ArcGIS. Taking into account ecological significance and features of common landscape indices as well as local ground truth, five indices were selected for the analysis. The indices included edge density (ED), Shannon’s diversity index (SDI), coefficient of variance of patch size (PSCOV), area-weighted mean patch fractal dimension (AWMPFD) and core area density (CAD). Based on average elevation and spatial distributions, landscape patterns in each catchment were analyzed. The effects of human activity and natural disturbance on regional landscape ecology were also discussed in the paper. All the indices analyzed in each catchment were synthesized using cluster analysis and combined with dominant landscape type in the catchment to build zoning maps of landscape. The results suggested that ED and CAD values increased as altitude gradually increased and significant vertical differentiation characteristics were noted. The SDI values gradually grew smaller with increasing altitude. Then PSCOV values showed inverted U-shaped trend with increasing altitude. The AWMPFD values did not show significant vertical differentiation characteristics. Three landscape ecology classes were regionalized in Qixia City. ClassⅠhad the smallest land area (10.14%) and stable agricultural zones. This implied that the landscape structure and scale were very stable and needed protection. ClassⅡhad the biggest land area (50.93%). Here, a

  15. The identification of suitable areas for afforestation in order to reduce the potential for surface runoff in the upper and middle sectors of Buzãu catchment

    Directory of Open Access Journals (Sweden)

    ROMULUS COSTACHE

    2015-07-01

    Full Text Available Deforestations, besides the global climate change, are the main cause of the intensification of f loods and flash - floods in the latest years. Since surface runoff is the main phenomenon leading to floods or flash - floods, afforestation is necessary, forest coverage being the element that retains most of the water from precipitation. The study area, repr esented by the upper and middle sectors of Buzau River basin, is one of the most affected regions of Romania by torrential phenomena. Also, the study area was chosen due to its considerable deforestation. This paper proposes a methodology created exclusive ly by GIS techniques in order to identify the areas suitable for afforestation. Thus, land cover and slope relief were taken into account when running the GIS model. Database processing and obtaining the final results were possible by implementing a workfl ow in Model Builder from ArcGIS 10.3, which can be later used as a tool for other study areas. The results of the study highlight Balaneasa, Bâsca Chiojdului and Sărăţel river basins, which record the highest shares of areas suitable for afforestation.

  16. 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...... 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....

  17. 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

  18. Biogeochemical and Hydrological Heterogeneity and Emergent Archetypical Catchment Response Patterns

    Science.gov (United States)

    Jawitz, J. W.; Gall, H. E.; Rao, P. S.

    2014-12-01

    What can stream hydrologic and biogeochemical signals tell us about interactions among spatially heterogeneous hydrological and biogeochemical processes at the catchment-scale? We seek to understand how the spatial structure of solute sources coupled with both stationary and nonstationary hydroclimatic drivers affect observed archetypes of concentration-discharge (C-Q) patterns. These response patterns are the spatially integrated expressions of the spatiotemporal structure of solutes exported from managed catchments, and can provide insight into likely ecological consequences of receiving water bodies (e.g., wetlands, rivers, lakes, and coastal waters). We investigated the following broad questions: (1) How does the spatial correlation between the structure of flow-generating areas and biogeochemical source areas across a catchment evolve under stochastic hydro-climatic forcing? (2) What are the feasible hydrologic and biogeochemical responses that lead to the emergence of archetypical C-Q patterns? and; (3) What implications do these coupled dynamics have for catchment monitoring and implementation of management practices? We categorize the observed temporal signals into three archetypical C-Q patterns: dilution; accretion, and constant concentration. We applied a parsimonious stochastic model of heterogeneous catchments, which act as hydrologic and biogeochemical filters, to examine the relationship between spatial heterogeneity and temporal history of solute export signals. The core concept of the modeling framework is considering the type and degree of spatial correlation between solute source zones and flow generating zones, and activation of different portions of the catchments during rainfall events. Our overarching hypothesis is that each archetype C-Q pattern can be generated by explicitly linking landscape-scale hydrologic responses and spatial distributions of solute source properties within a catchment. We compared observed multidecadal data to

  19. EVALUATION OF WATER RETENTION CAPABILITY IN WETLANDS AT SMALL FOREST CATCHMENT

    Directory of Open Access Journals (Sweden)

    Daniel Liberacki

    2015-07-01

    Full Text Available The paper presents the results of researches carried out in the middle part of Pizza Zielonka forest complex. The aim was the evaluation of retention changes at wetlands and mid-forest ponds. The object of the study was the catchment of the Trojanka watercourse, considering from the origin to the cross-section of Zielonka Lake. The catchment is located in in the central part of the Wielkopolska region, approximatelly 20 km on the North-East of Poznań. The area of this forestall catchment is about 223 ha. In the paper an analysis of the results from three hydrological years was presented. The results of the years 1987 (wet year, 2003 (dry year and 2009 (medium year were analysed against meteorological conditions. Retention capacity in each wetlands, as well as the possibility of water retention in the Trojanka watercourse was calculated. The researches confirmed significant meteorological conditions influence the amount of retentioned water. The calculated capacity of retentioned water was 15 852 m3 considering the total area of wetland and swamp (8,58 ha and precipitation sum of 555 mm. 18% increase of water capacity was observed in wet year (1987 In this year the sum of precipitation was 100 mm higher than multiyear average sum. Meanwhile 62% decrease of water capacity was observed in dry year (2003, when the precipitation sum was 208 mm lower than multiyear average one.

  20. 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 ...

  1. Stakeholder discourse and water management – implementation of the participatory model CATCH in a Northern Italian alpine sub-catchment

    Directory of Open Access Journals (Sweden)

    D. Collentine

    2008-03-01

    Full Text Available The Water Framework Directive (WFD, directive 2000/60/EC was created to ensure the sustainable use of water resources in the European Union. A central guideline included throughout the directive is a call for the participation of stakeholders in the management of these resources. Involving stakeholders is an important step to ensure that catchment management plans take into consideration local experience in the development of these plans and the impact of the plans on local interests. This paper describes and analyses the results of a series of workshops to facilitate implementation of the WFD at a catchment level based on the stakeholder participation model, CATCH. To test the usefulness of the CATCH model, developed for water management in a catchment area, a sub-catchment in an alpine valley in the north-east of Italy, the Alta Valsugana in the Province of Trento, was chosen as the setting for a series of workshops. In this valley water is fundamental for activities associated with agriculture, domestic use, energy production, sports and recreation. In the recent past the valley has had serious problems related to water quality and quantity. Implementation of water management plans under the WFD may lead to conflicts within the catchment between different stakeholder interest groups. Including stakeholders in the development of management plans not only follows the guidelines of the WFD but also could result in a more locally adapted and acceptable plan for the catchment. A new stakeholder analysis methodology was developed and implemented in order to identify the relevant stakeholders of the area and then two sets of workshops involving the key stakeholders identified were conducted in Spring 2006. The CATCH meetings were a new experience for the participants, who had to deal with both the principles of the WFD in general and the participation requirement in particular. During the meetings, the CATCH model played a very important role in

  2. 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

  3. 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

  4. 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

  5. State of elements of the environment in the broader area of former uranium mines in the catchment of the Trgoviski Timok

    Directory of Open Access Journals (Sweden)

    Nikić Zoran

    2013-01-01

    Full Text Available Mineral field ”Janja” extends over the Southwest slope of Stara Planina Mt., eastward from the village of Kalna in the belt of beech-fir forests. Exploitation of uranium used to be performed in three mines within this area, i.e. ”Mezdreja”, ”Gabrovnica”, and ”Srneći Do”, which are now closed down. One of the consequences of mining around these mines is partial degradation of natural balance. The greatest part of the terrain consists of granite, whereas metamorphic rocks are at the periphery. A geological survey with respect to the concentration of natural radioactive elements in the soil within the area of aforementioned mines has been conducted once so far. Alluvial sediment, ground and surface waters, as well as disposal were also examined. During the field study, radioactivity was measured and the methods of emanation and hydro-geochemical assessment were used, which was followed by collecting of samples for laboratory examination. The state of elements of the environment within the surveyed area is presented hereinafter on the basis of the existing data, having in mind that exploitation of uranium may disrupt natural balance in the long run. [Projekat Ministarstva nauke Republike Srbije, br. 37008: Održivo gazdovanje ukupnim potencijalima šuma u Republici Srbiji

  6. Chemical weathering and runoff chemistry in a steep headwater catchment

    Science.gov (United States)

    Anderson, Suzanne Prestrud; Dietrich, William E.

    2001-07-01

    We present here deductions about the location, rate, and mechanisms of chemical weathering in a small catchment based on a catchment-scale sprinkling experiment. In this experiment demineralized water was applied at an approximately steady rate in the CB1 catchment in the Oregon Coast Range to reach and maintain a quasi-steady discharge for a period of 4 days. Because of nearly steady flow conditions within the catchment, the contribution to solute fluxes from soil and bedrock could be partitioned. One half of the solute flux from the catchment derived from colluvial soil, and one half from weathering in bedrock. This implies more intense weathering in the thin colluvium mantling the catchment than in the thick underlying weathered bedrock. The annual solute flux from the catchment, scaled to the annual runoff from the catchment, is 32 +/- 10 t km-2 year-1, equivalent to published chemical denudation rates for nearby rivers with drainage areas 106 times greater than the experiment site. Soil waters sampled during the sprinkling experiment had steady compositions following a period of transient water flow conditions, implying steady-state chemical evolution in the soil. The waters leached organic anions from shallow depths in the soil, which solubilized aluminium and iron, indicating that podzolization is occurring in these soils. Carbonate dissolution appears to be an important source of solutes from the bedrock, despite being present as only a minor phase in the rock. Water balance suggests that the residence time of water in the catchment is about 2 months, and that typical 24 h storms displace only a fraction of the stored water. A consequence is that runoff chemistry is dominated by old water, which imposes strong limits on the variability of runoff composition.

  7. Understanding Hydrological Processes in an Ungauged Catchment in sub-Saharan Africa

    NARCIS (Netherlands)

    Mul, M.L.

    2009-01-01

    Ungauged catchments can be found in many parts of the world, but particularly in sub-Saharan Africa. Information collected in a gauged catchment and its regionalisation to ungauged areas is crucial for water resources assessment. Especially farmers in semi-arid areas are in need of such information.

  8. Surface-enhanced in-situ Raman-sensor applied in the arctic area for analyses of water and sediment

    Science.gov (United States)

    Kolomijeca, Anna; Kwon, Yong-Hyok; Kronfeldt, Heinz-Detlef

    2012-06-01

    Investigations on the seafloor in the arctic area are of great scientific interest as well as of progressive economic importance. Therefore, measurements in the water column and of sediments were carried out by applying different analytical methods. In JCR 253 arctic cruise a microsystem diode laser with reflection Bragg grating emitting at 671 nm was introduced and integrated into an optode housing which was laboratory pressure tested up to 200 bar. The connection to the mobile spectrometer is realized through an optical fiber. All performed measurements were carried out on the James-Clark-Ross research vessel during a three week experiment in August 2011. Conventional Raman spectra and SERS spectra of arctic surface water and sediment acquired from locations around 78° N and 9° E will be presented. Selected SERS substrates developed for SERS measurements in sea-water were tested for their capability to detect different substances in the water down to very small (pmol/l) concentrations. Additionally, the applicability of shifted excitation Raman difference spectroscopy (SERDS) and a combination of SERS with SERDS for analytical applications during sea-trials for in-situ analyses of sea-water and sediments will be discussed.

  9. 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

  10. GEODIVERSITY AUDIT AND ACTION PLAN FOR UPPER CATCHMENT AREA OF GERSA RIVER (RODNEI MOUNTAINS, BISTRIȚA-NĂSĂUD COUNTY, ROMANIA

    Directory of Open Access Journals (Sweden)

    Ioan Bâca

    2015-08-01

    Full Text Available Geodiversity Audit is an inventory and assessment process, wich represents the basis for elaborating the Geoconservation Action Plan. The geodiversity includes the abiotic factors (rocks, minerals, soils, landforms that sustain the life on the Earth, and owns economic, social, environmental, tourist and educational functions. This study proposes an audit of geodiversity from Gersa catcment area and an Action Plan for future planning and tourist valorization projects by local and county authorities. Gersa Valley is a geomorphological subunit located in the southern part of Rodnei Mountains (Bistrița-Năsăud County and contains in the superior sector some landforms with high degree of attractiveness, such as Izvorul Tăușoarelor Cave, Izvorul Calului Gorge and Bârlea Massif. By their configuration these landforms has a great potential for engaging in scientific and recreational activities (caving, hiking, gorge walking, canyoning, mountain biking. Keywords: geodiversity, geologic heritage, geoconservation, geosite, action plan, Rodnei Mountains, Gersa River, Izvorul Tăușoarelor Cave, speotourism, activ leisure

  11. Contamination history of suspended river sediments accumulated in oxbow lakes over the last 25 years. Morava river (Danube catchment area), Czech Republic

    Energy Technology Data Exchange (ETDEWEB)

    Babek, O. [Masaryk Univ., Brno (Czech Republic). Dept. of Geological Sciences; Palacky Univ., Olomouc (Czech Republic). Dept. of Geology; Hilscherova, K.; Holoubek, I.; Machat, J.; Klanova, J. [Masaryk Univ., Brno (Czech Republic). Research Centre for Environmental Chemistry and Ecotoxicology; Nehyba, S.; Zeman, J.; Famera, M. [Masaryk Univ., Brno (Czech Republic). Dept. of Geological Sciences; Francu, J. [Czech Geological Survey, Brno (Czech Republic)

    2008-06-15

    Background, aims, and scope Embankment of meandering river systems in many industrial areas results in the formation of artificial oxbow lakes that may act as perennial or intermittent traps for river sediments. Their deposits can be dated using a combination of historical and stratigraphic data, providing a good means to study historical records of contamination transported by rivers. Contamination history over the last few decades is of special significance for Central and Eastern Europe as it can reflect high pollutant levels in the second half of the twentieth century and the subsequent improvement after the fall of the Iron Curtain. The purpose of this study was to investigate recent sediments of an oxbow lake of the Morava River, Czech Republic, their stratigraphic records, sediment architecture, and history of contamination. Materials and methods Seven ground-penetrating radar (GPR) profiles and three sediment cores up to 4 m deep were studied. The stratigraphy of the cores was inferred from visible-light spectrophotometry, X-ray radiography, grain size analysis, and semiquantitative modal analysis of sandy fractions. The sediments were dated using the {sup 137}Cs mass activity and combinations of stratigraphic and historical data. The cores were sampled for concentrations of heavy metals and persistent organic pollutants. Wet sampled, lyophilized, and sieved sediments were extracted and analyzed for heavy metals by inductively coupled plasma mass spectrometry (ICP-MS) of aqua regia leachate and for persistent organic pollutants by gas chromatography (GC-ECD and GC-MS). Results Three distinct sedimentary sequences (S1, S2, and S3) were identified. The basal sequence S1 represents river channel sediments deposited before the formation of the oxbow lake, most likely before the 1930s. The boundary between the S1 and S2 sequence correlates with the level of sediment dredging from 1981 evidenced from historical data. The overlying sequences S2 and S3 represent a

  12. Contamination history of suspended river sediments accumulated in oxbow lakes over the last 25 years. Morava river (Danube catchment area), Czech Republic

    International Nuclear Information System (INIS)

    Background, aims, and scope Embankment of meandering river systems in many industrial areas results in the formation of artificial oxbow lakes that may act as perennial or intermittent traps for river sediments. Their deposits can be dated using a combination of historical and stratigraphic data, providing a good means to study historical records of contamination transported by rivers. Contamination history over the last few decades is of special significance for Central and Eastern Europe as it can reflect high pollutant levels in the second half of the twentieth century and the subsequent improvement after the fall of the Iron Curtain. The purpose of this study was to investigate recent sediments of an oxbow lake of the Morava River, Czech Republic, their stratigraphic records, sediment architecture, and history of contamination. Materials and methods Seven ground-penetrating radar (GPR) profiles and three sediment cores up to 4 m deep were studied. The stratigraphy of the cores was inferred from visible-light spectrophotometry, X-ray radiography, grain size analysis, and semiquantitative modal analysis of sandy fractions. The sediments were dated using the 137Cs mass activity and combinations of stratigraphic and historical data. The cores were sampled for concentrations of heavy metals and persistent organic pollutants. Wet sampled, lyophilized, and sieved sediments were extracted and analyzed for heavy metals by inductively coupled plasma mass spectrometry (ICP-MS) of aqua regia leachate and for persistent organic pollutants by gas chromatography (GC-ECD and GC-MS). Results Three distinct sedimentary sequences (S1, S2, and S3) were identified. The basal sequence S1 represents river channel sediments deposited before the formation of the oxbow lake, most likely before the 1930s. The boundary between the S1 and S2 sequence correlates with the level of sediment dredging from 1981 evidenced from historical data. The overlying sequences S2 and S3 represent a

  13. Design of a Rainwater Catchment System

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    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.

  14. Modelled seasonal forecasts of snow water equivalent and runoff in alpine catchments

    Science.gov (United States)

    Förster, Kristian; Hanzer, Florian; Schöber, Johannes; Huttenlau, Matthias; Achleitner, Stefan; Strasser, Ulrich

    2016-04-01

    Seasonal forecasts of water balance components are becoming increasingly important for hydrological applications. These forecasts are typically derived from coupled atmosphere-ocean climate models, which enable physically based seasonal forecasts. In mountainous regions, however, topography is complex whilst typical spatial resolutions of the climate models are still comparably coarse, i.e in the data, ridges and valleys are not represented with sufficient accuracy. Therefore, seasonal predictions of atmospheric variables require consideration of representative gradients. We present first results of seasonal forecasts and re-forecasts processed by the NCEP (National Centers for Environmental Prediction) Climate Forecast System version 2 (CFSv2). These are prepared for monthly time steps in order to be used for ensemble runs of water balance simulation using the Alpine Water balance And Runoff Estimation model (AWARE). This model has been designed for monthly seasonal predictions in ice- and snowmelt dominated catchments. The study area is the Inn catchment in Tyrol/Austria, including its headwaters in Switzerland. Results are evaluated for both anomalies of meteorological input data (temperature and precipitation), as well as balance components including snow water equivalent and runoff, both simulated with AWARE. Based on model skill evaluations derived from forecasts and observations, the model chain CFSv2 - AWARE proves helpful to analyse possible future hydrological system states of mountainous catchments with emphasis on spatio-temporal snow cover evolution.

  15. 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.

  16. Hydrological impact of water and soil conservation works in the Merguellil catchment of central Tunisia

    OpenAIRE

    Lacombe, Guillaume; Cappelaere, Bernard; Leduc, Christian

    2008-01-01

    The Merguellil catchment (1183 km(2)), whose runoff is a major water resource for the Kairouan area in semi-arid Tunisia, was equipped with water and soil conservation works (WSCW) during the 1990s, mainly to reduce soil erosion and sitting of the downstream El Haouareb dam. The spatial configuration of the hydro-meteorological station network makes it possible to characterize the catchment-scale hydrological impact of the WSCW. The catchment is subdivided into two parts, the upper subcatchme...

  17. Chemical erosion intensity in the Nišava catchments

    OpenAIRE

    Manojlović Predrag A.

    2002-01-01

    The Nišava catchment comprehends the area of 4068 km2. There are differences in erosion intensity due to different physical-geographical characteristics of that area. Mechanical water erosion in the Nišava catchment is 302,4 m3/km2/yr and chemical erosion is 67,2 t/km2/yr. Space differences are large (47,1-115.5 t/km2/yr) and are mostly determined by hydrological and lithological characteristics of that area.

  18. Susceptibility of Shallow Landslide in Fraser Hill Catchment, Pahang Malaysia

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    Wan Nor Azmin Sulaiman

    2010-01-01

    Full Text Available 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 was prepared for the 8.2 km2 catchment. A GIS based deterministic model was then applied to predict the spatial landslide occurrence within catchment. Model input parameters include bulk density, friction angle, cohesion and hydraulic conductivity were gathered through in situ and lab analysis as well as from previous soil analysis records. Landslides locations were recorded using GPS as well as previous air photos and satellite imagery to establish landslide source areas inventory. The landslide susceptibility map was produced under different precipitation event’s simulation to see the effects of precipitation to stability of the hill slopes of the catchment. The results were categorized into naturally unstable (Defended, Upper Threshold, Lower Threshold, marginal instability (Quasi Stable and stable area (Moderately Stable and Stable. Results of the simulation indicated notable change in precipitation effect on Defended area is between 10mm to 40mm range in a single storm event. However, when storm event is exceeded 120mm, the result on Defended area produced by the model tends to be constant further on. For area categorized as naturally unstable (Factor of Safety, SF<1, with 110 mm of precipitation in a single storm event and soil depth at 2 meters and 4 meters could affect 69.51% and 69.88% respectively of the catchment area fall under that class. In addition, the model was able to detect 4% more of the landslide inventory under shallower soil depth of

  19. 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

    , but also with regional paleoflood and paleoclimate records. The aggradation of flood deposits with contribution from the highest catchment area (up to 2200 m) occurred predominantly during periods with cooler summer temperature, reduced solar irradiance and phases of drier spring-summer. This hydro-sedimentological pattern matches mostly to the variability of the flood proxies of the much larger and higher Aare catchment (4274 m) despite of the differences in catchment lithology; altitudinal vegetation belts; topography; snow and glacier cover; periglacial and slope processes; and intermediate sediment storage. Spectral analysis of the geochemical time series from different size catchments and climate proxies (TSI, 18O, tree-rings, NAO, SNAO) evidence similar periodicities during the last Millennia. Comparing the sedimentary flood proxies from the basins analysed and the Summer NAO index from 1670 to 2000, severe floods occurred mostly during positive SNAO modes. This result is supported by our findings regarding the influence of low-frequency atmospheric circulation pattern on summer floods in Switzerland (1800-2008). Thus, the mechanisms of flood processes from the different catchments are strongly influenced by North Atlantic dynamics and solar forcing. From the data obtained we suggest that the geochemical record of the small Eistlenbach catchment provides accurate paleoclimate information at least at a decadal time resolution.

  20. Assessing the role of urban developments on storm runoff response through multi-scale catchment experiments

    Science.gov (United States)

    Wilkinson, Mark; Owen, Gareth; Geris, Josie; Soulsby, Chris; Quinn, Paul

    2015-04-01

    Many communities across the world face the increasing challenge of balancing water quantity and quality issues with accommodating new growth and urban development. Urbanisation is typically associated with detrimental changes in water quality, sediment delivery, and effects on water storage and flow pathways (e.g. increases in flooding). In particular for mixed rural and urban catchments where the spatio-temporal variability of hydrological responses is high, there remains a key research challenge in evaluating the timing and magnitude of storage and flow pathways at multiple scales. This is of crucial importance for appropriate catchment management, for example to aid the design of Green Infrastructure (GI) to mitigate the risk of flooding, among other multiple benefits. The aim of this work was to (i) explore spatio-temporal storm runoff generation characteristics in multi-scale catchment experiments that contain rural and urban land use zones, and (ii) assess the (preliminary) impact of Sustainable Drainage (SuDs) as GI on high flow and flood characteristics. Our key research catchment, the Ouseburn in Northern England (55km2), has rural headwaters (15%) and an urban zone (45%) concentrated in the lower catchment area. There is an intermediate and increasingly expanding peri-urban zone (currently 40%), which is defined here as areas where rural and urban features coexist, alongside GIs. Such a structure is typical for most catchments with urban developments. We monitored spatial precipitation and multiscale nested (five gauges) runoff response, in addition to the storage dynamics in GIs for a period of 6 years (2007-2013). For a range of events, we examined the multiscale nested runoff characteristics (lag time and magnitude) of the rural and urban flow components, assessed how these integrated with changing land use and increasing scale, and discussed the implications for flood management in the catchment. The analyses indicated three distinctly different

  1. Internally Drained Supraglacial River Catchments on the Southwest Greenland Ice Sheet

    Science.gov (United States)

    Yang, K.; Smith, L. C.; Chu, V. W.; Pitcher, L. H.; Gleason, C. J.

    2015-12-01

    Internally drained catchments are the hydrologic units on the Greenland ice sheet (GrIS) surface that collect and drain meltwater into moulins or supraglacial lakes without out flows. Understanding the spatial pattern of these internal catchments is critical, which can provide key information about how supraglacial meltwater is transported and released on the ice surface. This study proposed an automatic approach to detect supraglacial hydrologic features (rivers, lakes, moulins, and internal catchments) located at southwest GrIS from Landsat-8 OLI panchromatic imagery. A total of 800 internal catchments are delineated and the average catchment size (river network length) is found to increase with elevations. In addition, moulins are the prime way to drain internal catchments and the average moulin densities decrease with elevations. Adaptive depression area thresholds are calculated to achieve optimal match between DEM-modeled and image-detected internal catchment patterns. The pattern of these image-detected internal catchments also indicates that: 1) not all the DEM-modeled topographic depressions act as meltwater sinks; 2) moulin distribution greatly impacts the internal catchment patterns; and 3) topographic depressions can be connected downstream without being fully filled, changing the fragmentary of the internal catchments.

  2. Stable isotope analyses reveal the importance of seagrass beds as feeding areas for juvenile Myrophic punctatus in Florida

    Science.gov (United States)

    The feeding habits and habitats of the speckled worm eel Myrophis punctatus were studied on the mangrove edge of the Indian River Lagoon (Florida) using stomach contents and stable isotope analyses of carbon (δ13C) and nitrogen (δ15N). Stomach dietary analyses identified four tax...

  3. 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

  4. 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

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

    Directory of Open Access Journals (Sweden)

    T. Doppler

    2012-07-01

    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 vary 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. Water samples were collected at different locations in the catchment (overland flow, tile drains and open channel for two months after application in 2009, 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.

    Despite the frequent and wide-spread occurrence of overland flow, most of this water did not reach the channel directly, but was retained in small depressions in the catchment. From there, it reached the stream via macropores and tile drains. Manholes of the drainage system and storm drains for road and farmyard runoff acted as

  6. Geomorphologic coupling and decoupling in a Mediterranean mountain catchment under changing environmental conditions as evidenced by sediment fingerprinting

    Science.gov (United States)

    D'Haen, Koen; Verstraeten, Gert; Degryse, Patrick; Dusar, Bert; Waelkens, Marc

    2010-05-01

    Soil erosion, sediment deposition and sediment delivery are intimately coupled with human activities. This is also the case for the Mediterranean environment where intense human impact during the classical period (Hellenistic to Roman Period) has caused widespread erosion and alluviation. Many studies, however, have illustrated that this coupling is not always straightforward as it not only depends on the intensity of human impact, but also on the spatial patterns of land use changes and internal geomorphic system controls. As a result, different locations within a landscape may react differently to a single catchment disturbance event. Within this study, the spatial and temporal sediment dynamics for the 264 km² large Büğdüz catchment are analysed. This catchment is situated in the western part of the territory of the classical city of Sagalassos, Taurus Mountain range, 100 km north of Antalya. Previous sedimentological studies have shown that especially during the period 900 BCE-600CE human activities triggered intense sedimentation in upland areas, whereas for more recent periods sediment dynamics are more limited and restricted to some alluvial units. It can be questioned what the decrease in (spatial) sediment dynamics in the Büğdüz catchment caused: decreasing human activity, changing spatial patterns of human impact or internal geomorphic processes. Indeed, archaeological surveys have shown that spatial patterns of settlement patterns have changed through time. Therefore, we used a sediment fingerprinting technique in order to elucidate the sediment sources and to get an idea of the connectivity between the various parts of the catchment. Ninety-four cores were taken within the alluvial plain, and numerous topsoil samples were taken over the entire catchment. All samples were wet sieved into three factions, a gravel (>2 mm), a sand (2>x>63 μm) and a silt/clay fraction (impact did influence the coupling of the various geomorphic subsystems in the

  7. 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.

  8. Factors controlling inter-catchment variation of mean transit time with consideration of temporal variability

    Science.gov (United States)

    Ma, Wenchao; Yamanaka, Tsutomu

    2016-03-01

    The catchment transit time, a lumped descriptor reflecting both time scale and spatial structure of catchment hydrology can provide useful insights into chemical/nuclear pollution risks within a catchment. Despite its importance, factors controlling spatial variation of mean transit time (MTT) are not yet well understood. In this study, we estimated time-variant MTTs for about ten years (2003-2012) in five mesoscale sub-catchments of the Fuji River catchment, central Japan, to establish the factors controlling their inter-catchment variation with consideration of temporal variability. For this purpose, we employed a lumped hydrological model that was calibrated and validated by hydrometric and isotopic tracer observations. Temporal variation patterns of estimated MTT were similar in all sub-catchments, but with differing amplitudes. Inter-catchment variation of MTT was greater in dry periods than wet periods, suggesting spatial variation of MTT is controlled by water 'stock' rather than by 'flow'. Although the long-term average MTT (LAMTT) in each catchment was correlated with mean slope, coverage of forest (or conversely, other land use types), coverage of sand-shale conglomerate, and groundwater storage, the multiple linear regression revealed that inter-catchment variation of LAMTT is principally controlled by the amount of groundwater storage. This is smaller in mountainous areas covered mostly by forests and greater in plain areas with less forest coverage and smaller slope. This study highlights the topographic control of MTT via groundwater storage, which might be a more important factor in mesoscale catchments, including both mountains and plains, rather than in smaller catchments dominated by mountainous topography.

  9. Watershed scale spatial variability in dissolved and total organic and inorganic carbon in contrasting UK catchments

    Science.gov (United States)

    Cumberland, S.; Baker, A.; Hudson, N. J.

    2006-12-01

    Approximately 800 organic and inorganic carbon analyses have been undertaken from watershed scale and regional scale spatial surveys in various British catchments. These include (1) a small (wetlands for all sample sites. (4) In the urbanized Ouseburn catchment, although many sample sites also show this same mixing trend, some tributaries follow a pollutant trend of simultaneous increases in both DOC and DIC. The Ouseburn is part of the larger Tyne catchment: this larger catchment follows the simple groundwater DIC- soil water DOC end member mixing model, with the exception of the urban catchments which exhibit an elevated DIC compared to rural sites. (5) Urbanization is demonstrated to increase DIC compared to equivalent rural catchments; this DIC has potential sources including diffuse source inputs from the dissolution of concrete, point sources such as trade effluents and landfill leachates, and bedrock derived carbonates relocated to the soil dissolution zone by urban development. (6) DIC in rural SW England demonstrates that spatial variability in DIC can be attributed to variations in geology; but that DIC concentrations in the SW England rivers dataset are typically lower than the urbanized Tyne catchments despite the presence of carbonate bedrock in many of the sample catchments in the SW England dataset. (7) Recent investigations into carbon fluxes in British rivers have focused on long term increases in DOC in rural and predominantly upland catchments. Our results suggest that research is needed into understanding long term variations in inorganic carbon concentration, as well as total (organic and inorganic) carbon fluxes from British rivers, to obtain total carbon loads. In particular, we provide evidence that DIC concentrations may be greater in urbanized catchments compared to equivalent non-urban catchments, with the implication that increasing urbanization in the future will see increases in riverine DIC and a decrease in the strength of any DOC

  10. Water level and response time of rivers during flash floods derived from a nested network in the Claduègne Mediterranean catchment (43 km2)

    Science.gov (United States)

    Gonzalez-Sosa, Enrique; Braud, Isabelle; Molinié, Gilles; Nord, Guillaume; Vandervaere, Jean-Pierre; Uber, Magdalana

    2016-04-01

    time (time between the initiation of rainfall and a significant water level rise) and rising time (time between the water level significant rise and peak water level) were derived. The results are impacted by the cross sections of the river. Some events show that the reaction and rising time follow an expected upstream-downstream propagation into the river network, while, for other events, this is not the case independently of homogeneity and spatial distribution of precipitation cells. Statistical analyses were also performed to search for relationships between rainfall characteristics, antecedent soil moisture, catchments characteristics and the hydrological response. The results of the analysis are also used to assess the validity of the underlying physical hypotheses of the IRIP method (Intense Pluvial Runoff Indicators, Lagadec et al., 2016) allowing the mapping of areas prone to runoff generation, transfer and accumulation. References Braud et al., 2014. Multi-scale hydrometeorological observation and modelling for flash-flood understanding, Hydrology and Earth System Sciences, 18, 3733-376. Lagadec et al., 2016. Description and evaluation of an intense surface runoff susceptibility mapping method, J. Hydrology, in revision. Nord et al., in prep. A high space-time resolution dataset linking meteorological forcing and hydro-sedimentary response in a masoscale Mediterranean catchment (Auzon) of the Ardèche regione, France, Earth Systems Sciences Data.

  11. Sensitivity of the Runoff Characteristics of Small Alpine Catchments to Climate Change

    Science.gov (United States)

    Meißl, Gertraud; Klebinder, Klaus; Formayer, Herbert; Kerl, Florian; Schöberl, Friedrich; Geitner, Clemens; Markart, Gerhard; Kohl, Bernhard; Nadeem, Imran; Leidinger, David; Bronstert, Axel; Bürger, Gerd

    2016-04-01

    , whose surface runoff reaction is not sensitive to antecedent soil moisture content (here especially forests and sites with a priori high level runoff). Thus, the reduction of days with wet conditions in summer will affect mainly catchments with a high percentage of sites of the first type, reducing surface runoff. According to the analysis of the climate scenarios, the number of days with dried up litter layer will strongly increase by 8-11% in the two lower situated catchments. Thus catchments with a high percentage of area susceptible to hydrophobic effects (e.g. pastures with high proportion of mat grass Nardus stricta) may show increased surface runoff in case of precipitation events with high intensity after dry periods. The analyses of the maximum intensity of heavy precipitation events indicate a clear increase up to 10% till the end of the century. If one of these trends equalizes the other out resulting in unchanged occurrence probabilities of extreme runoff events, cannot be answered generally because of the local characteristics of relevant processes and uncertainties regarding the modelling chain. Regardless of the open question about its return period, peak runoff of extreme events may increase by approximately 25% comparing to current peak runoff due to the higher rain intensities.

  12. Understanding Hydrological Processes in an Ungauged Catchment in sub-Saharan Africa

    NARCIS (Netherlands)

    Mul, M.L.

    2009-01-01

    Ungauged catchments can be found in many parts of the world, but particularly in sub-Saharan Africa. Information collected in a gauged catchment and its regionalisation to ungauged areas is crucial for water resources assessment. Especially farmers in semi-arid are in need of such information. Inter

  13. 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

  14. Understanding sediment sources in a peri-urban Mediterranean catchment using geochemical tracers

    Science.gov (United States)

    Ferreira, Carla; Walsh, Rory; Kikuchi, Ryunosuke; Blake, Will

    2016-04-01

    One of the main physical environmental impacts of urbanization is an increase in suspended sediment concentrations and loads, particularly in the constructional phase. Impacts in peri-urban catchments characterized by a mosaic of urban and non-urban landscape elements with varying roles in acting as sources and sinks of overland flow and slope wash have received little attention, particularly in Mediterranean environments. The present study uses a sediment 'fingerprinting' approach to determine the main sediment sources in the peri-urban Ribeira dos Covões catchment (6.2km2) in Portugal and how they change during storm events following contrasting antecedent weather. The catchment, rural until 1972, underwent discontinuous urbanization in 1973-1993, followed by an urban consolidation phase. Currently, its land-use is a complex mosaic of woodland (56%), urban (40%) and agricultural (4%) land parcels. Distinct urban patterns include some well-defined urban residential centres, but also areas of discontinuous urban sprawl. Since 2010, a major road was built and an enterprise park has been under construction, covering 1% and 5% of the catchment, respectively. The catchment has a Mediterranean climate. The geology comprises sandstone (56%), limestone (41%) and alluvial deposits (3%). Soils are generally deep (>3.0m), but shallow (transported fluvial material. Three fine bed-sediment sampling surveys were carried out after (i) a long dry period (21/09/2012), (ii) a winter storm of relatively high rainfall intensity (23.2mm day-1) (19/02/2015), and (iii) after several storms in Spring (22/04/2015). All samples were oven-dried (at 38° C) and sieved to obtain different particle size fractions (0.125-2.000mm, 0.063-0.125mm and road surface immediately it entered the stream network. The elemental composition (40 elements) of each size fraction was assessed using a Niton X-ray fluorescence elemental analyser. Results show that rock type has a profound influence on the

  15. Vulnerabilidades sociais e juvenil nos mananciais da zona sul da cidade de São Paulo Social vulnerabilities and youth in the water catchment areas of the southern zone of the city of São Paulo

    Directory of Open Access Journals (Sweden)

    Elizabeth Borelli

    2012-06-01

    Full Text Available Este artigo é um produto parcial da pesquisa "Reflexos da Vulnerabilidade Socioambiental nas Manifestações Musicais dos Jovens Paulistanos da Periferia", identificando como recorte geográfico a periferia da Zona Sul da cidade de São Paulo. Trata-se de uma região que começou a se formar devido à ocupação populacional desordenada em áreas de manancial, onde a vulnerabilidade social é agravada por situações de risco e degradação ambiental, dado o adensamento das áreas de favelas, configurando um processo de exclusão ambiental e urbana. Temporalmente, a pesquisa parte da década de 1980, quando se expande o padrão de extensão da periferia e surgem as manifestações culturais nas periferias dos grandes centros urbanos. Nesta reflexão, a relação entre política e cultura é apresentada através da análise dos mecanismos de sociabilidade que articulam os jovens afrodescendentes das periferias em torno de intervenções culturais coletivas, como formas de criação e reprodução da sua realidade social.This article is a partial product of the study "Reflexes of the Socio-environmental Vulnerability in the Musical Manifestations of Paulista Youth from the Periphery," which focuses on the Southern Zone of the city of São Paulo. This is a region that took shape through the unordered occupation of water catchment areas, where social vulnerability is aggravated by situations of risk and environmental degradation, given the increased density of favela regions, establishing a process of environmental and urban exclusion. The study begins in the 1980s, when the pattern of extension of the periphery expanded and cultural manifestations arose in the peripheries of the large urban centers. In this reflection, the relationship between politics and culture is presented through the analysis of the mechanisms of sociability that articulate Afro-descendent youth from the periphery around collective cultural interventions, as forms of creation

  16. Using Arc GIS to analyse urban growth towards torrent risk areas (Aswan city as a case study)

    International Nuclear Information System (INIS)

    Areas suffering from storm water drains are considered to be the places most at risk, water torrents have an effect on urban areas and can cause a lot of damage to buildings and infrastructure. Moreover, there is dangerous situation whereby urban growth is occuring towards at-risk areas. The urban growth rate in risk areas rose up to 24.9% in 2001, and reached 48.8% in 2013. Urban growth in ''Abouelreesh'' village had been influenced by the construction of larger buildings, because most people were looking forward to live in bigger houses. We can discover the previous problem by observing the average size increase of the buildings' areas from 2001 until 2013, especially in risky areas where the average building's area had grown from 254 m2 in 2001 to 411 m2 in 2013. This Phenomenon is considered to be very important factor which attracts the urban growth towards the risky areas in spite of the danger surrounding them

  17. Streamflow Characteristics of Two Forested Catchments in the Sopron Hills

    Directory of Open Access Journals (Sweden)

    GRIBOVSZKI, Zoltán

    2006-01-01

    Full Text Available One of the central issues in hydrology is today to establish a relationship between thehydrological and biological processes in ecosystems. One question of this theme is the vegetationimpact on the water budget of the catchment. Water use by vegetation can closely be linked tostreamflow patterns on a variety of time scales. At present many details of these connections arepoorly understood.Investigation on small catchments is the best way of studying hydrological processes in headwater,forested watersheds. In this paper drainage basin morphology and streamflow characteristics (baseflow and quick flow have been analysed under conditions of forest management in two neighbouringsmall forested catchments (the Farkas Valley and Vadkan Valley located in the prealpine hillsbordering to Austria on the basis of streamflow data collected during 2001.

  18. 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

  19. 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

  20. 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

  1. Using streamflow and hydrochemical tracers to conceptualise hydrological function of underground channel system in a karst catchment of southwest China

    Science.gov (United States)

    Zhang, Zhicai; Chen, Xi; Wang, Jinli

    2016-04-01

    Karst hydrodynamic behaviour is complex because of special karst geology and geomorphology. The permeable multi-media consisting of soil, epikarst fractures and conduits has a key influence on karst hydrological processes. Spatial heterogeneity is high due to special landforms of vertical shafts, caves and sinkholes, which leads to a high dynamic variability of hydrological processes in space and time, and frequent exchange of surface water and groundwater. Underground water in different reach were sampled over the 1996-2001 in a karst catchment of Houzhai, with 81km2, located in Guizhou province of southwest China. Samples were analysed for water temperature, pH, conductivity and four solute concentrations. The monitoring sought to assess the combined utility of flow discharge and natural geochemical tracers in upscaling flow structure understanding in karst area. Based on previous researches and field investigation, the catchment characteristics were explored with the use of a GIS. Both flow discharge and solute concentrations exhibited clear seasonal patterns at every groundwater sampling sites. The variations of flow and chemistry are more dramatic in upstream site with less soil cover and more sinkholes development, which affect the hydrological pathways significantly. There was clear evidence that the differences in geology and soil were the main controls on hydrology and flow chemistry, which was spatially variable in different sites of underground channel. Conceptual flow structures in main hydrological response units for different area in the catchment were developed according to the variation of discharge and flow chemistry.

  2. Effect of the spatial distribution of physical aquifer properties on water table depth and stream discharge in a headwater catchment

    Directory of Open Access Journals (Sweden)

    C. Gascuel-Odoux

    2009-11-01

    Full Text Available Water table depth and its dynamics is often poorly predicted upslope despite they control both water transit time within the catchment and solute fluxes at the catchment outlet. The paper analyses how relaxing the assumption of lateral homogeneity of physical properties can improve simulations of water table depth and dynamics. Four different spatial models relating of saturated hydraulic conductivity to topography have been tested: a simple linear relationship, a linear relationship with two topographic indexes, two domains with a transitional area. The Hill-Vi model has been modified to test these hypotheses. The studied catchment (Kervidy-Naizin, western France is underlain by schist crystalline bedrock. A shallow and perennial groundwater highly reactive to rainfall events mainly develops in the weathered saprolite layer. The results indicate that 1 discharge and the water table in the riparian zone are similarly predicted with the four models, 2 distinguishing two domains constitutes the best model and slightly improves prediction of the water table upslope, and 3 including spatial variations in the other parameters such as porosity or rate of hydraulic conductivity decrease with depth does not improve the results. These results underline the necessity of better investigation of upslope areas in hillslope hydrology.

  3. 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

  4. Processes controlling groundwater chemistry and identification of water resource vulnerability: Yarra catchment, Victoria

    International Nuclear Information System (INIS)

    Full text: Assessment of processes controlling groundwater chemistry is essential for water resource management and identification of water resource vulnerability. The Yarra Catchment (4045 km2) extends 120 km east of Melbourne and is considered a significant area for Melbourne's water resources. This catchment is characterised by fractured rock aquifers, a high baseflow component, high, localised recharge, and diverse land use. Therefore, identification of processes controlling groundwater chemistry is important for determining areas where groundwater, and inevitably surface water, are most vulnerable to contamination. The regional groundwater flow system is affected by high, localised recharge in areas of high surface elevations. Hence, a local groundwater flow system is investigated in detail to aid regional interpretation. Processes causing spatial heterogeneity of groundwater chemistry include the extent of recharge, water-rock interaction and land use processes. At high surface elevations Na:CI = 1, and direct recharge of precipitation into sedimentary or granitic aquifers results in groundwater with lower TDS values (∼ 50 to 100 mg/L), compared to groundwater where precipitation directly recharges younger basaltic aquifers (TDS ∼ 100 to 150 mg/L). At lower surface elevations Na:CI ratios decrease, and major ion concentrations, pH and TDS are significantly higher (TDS ∼ 400 to 500 mg/L) reflecting cumulative effects of water-rock interaction and agricultural land use lower in the catchment. Groundwater samples were also analysed for stable isotopes, the 180 and 2H values (-6.2 to 5.50, and -38.1 to 32.20 VSMOW respectively) lie on the Melbourne Meteoric Water Line, indicating that groundwater has not been subjected to evaporation or high-temperature water rock interaction. Slightly lower 180 and 2H values for groundwater compared to nearby surface water indicates that recharge of colder rains occurs preferentially, both on local and more regional scales

  5. 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...

  6. Sediment transport in steep forested catchments: the role of disturbance and scale

    Science.gov (United States)

    Hancock, Greg; Hugo, James; Webb, Ashley

    2016-04-01

    Sediment loads (both bedload and suspended sediment) are difficult to measure due to the time and equipment needed. However such data is needed to understand overall sediment transport rates, landscape evolution, effect of human disturbance as well as patterns and temporal response. There is a dearth of such data sets globally let along for Australia. Here we present the findings from 8 steep slope forested catchments dominated by headwater streams (size range 15-100 hectares) in south-eastern Australia where both bedload and suspended load have been measured over multiple years. The results demonstrate that suspended load is the dominant component. There appears to be no consistent suspended to bedload ratio for the catchments. The suspended sediment to bedload ratio appears to be catchment specific. There was no relationship between total load (or bedload/suspended load) and average catchment slope, stream length, shape or any geomorphic descriptor. Again this appears to be catchment specific. However catchment total load was found to be significantly related to catchment area and demonstrates strong log-log linear behaviour. Comparing these total loads with total load data from a nearby larger catchments (100km2 to 1000km2) demonstrates that there is a significant scaling relationship across all catchment sizes in this region. The scaling relationships found here are similar to those found globally and provide a unique insight into an understudied system. The data also provides the ability to assess sediment transport models and their reliability across different scales.

  7. Detecting non-stationary hydrologic model parameters in a paired catchment system using data assimilation

    Science.gov (United States)

    Pathiraja, S.; Marshall, L.; Sharma, A.; Moradkhani, H.

    2016-08-01

    Non-stationarity represents one of the major challenges facing hydrologists. There exists a need to develop modelling systems that are capable of accounting for potential catchment changes, in order to provide useful predictions for the future. Such changes may be due to climatic temporal variations or human induced changes to land cover. Extensive research has been undertaken on the impacts of land-use change on hydrologic behaviour, however, few studies have examined this issue in a predictive modelling context. In this paper, we investigate whether a time varying model parameter estimation framework that uses the principles of Data Assimilation can improve prediction for two pairs of experimental catchments in Western Australia. All catchments were initially forested, but after three years one catchment was fully cleared whilst another had only 50% of its area cleared. Their adjacent catchments remained unchanged as a control. Temporal variations in parameters were detected for both treated catchments, with no comparable variations for the control catchments. Improved streamflow prediction and representation of soil moisture dynamics were also seen for the time varying parameter case, compared to when a time invariant parameter set from the calibration period was used. While we use the above mentioned catchments to illustrate the usefulness of the approach, the methods are generic and equally applicable in other settings. This study serves as an important validation step to demonstrate the potential for time varying model structures to improve both predictions and modelling of changing catchments.

  8. Marginality Phenomena and New Uses on the Agricultural Land. Diachronic and Spatial Analyses of the Molise Coastal Area

    Directory of Open Access Journals (Sweden)

    Donatella Cialdea

    2014-05-01

    Full Text Available This paper analyzes the evolution of land use in the Molise Region. The attention is focused on the changes that occurred primarily on the rural area of the coastal area in this Region.  The presence of urban centers of limited dimension, both for the demographic performance and for the dimensional order, is the main characteristic of this area. The historic part of rural tradition, at the same time, no longer emerges as a primary component of the regional landscape. This trend is particularly evident in the coastal zone, which is analyzed in this work not only in the range of areas that directly bordering the Adriatic Sea, but also in its pre-coastal zone, which remains imprinted on a matrix rural, but suffering from marginalization phenomena

  9. A Vector-based Method for the Extraction of Catchment from Grid DEMs

    Institute of Scientific and Technical Information of China (English)

    ZHU Qing; TIAN Yixiang

    2005-01-01

    The methodology of catchment extraction especially from regular grid digital elevation models (DEMs) is briefly reviewed.Then an efficient algorithm, which combines vector process and traditional neighbourhood raster process, is designed for extracting the catchments and subcatchments from depressionless DEMs.The catchment area of each river in the grid DEM data is identified and delineated, then is divided into subcatchments as required.Compared to traditional processes, this method for identifying catchments focuses on the boundaries instead of the area inside the catchments and avoids the boundary intersection phenomena.Last, the algorithm is tested with a set of DEMs of different sizes, and the result proves that the computation efficiency and accuracy are better than existent methods.

  10. Assessing the drivers of dissolved organic matter export from two contrasting lowland catchments, U.K.

    Science.gov (United States)

    Yates, Christopher A; Johnes, Penny J; Spencer, Robert G M

    2016-11-01

    Two lowland catchments in the U.K. were sampled throughout 2010-11 to investigate the dominant controls on dissolved organic matter quantity and composition. The catchments had marked differences in terms of nutrient status, land cover and contrasting lithologies resulting in differences in the dominant flow pathways (groundwater vs. surface water dominated). The Upper Wylye is a chalk stream with a baseflow index of 0.98, draining a catchment dominated by intensive agricultural production. Millersford Brook is a lowland peat catchment with a baseflow index of 0.43, draining a semi-natural catchment with heather moorland and coniferous forest. Samples were collected weekly between October 2010 and September 2011 from eleven sampling locations. Samples were analysed to determine dissolved organic carbon, nitrogen and phosphorus fractions with DOM composition evaluated via the DOC:DON ratio, DOC:DOP ratio, specific UV absorption at 254nm, absorbance ratio (a250:a365) and the spectral slope parameter between 350 and 400nm (S350-400). Significant differences were observed in all determinands between the catchments, over time, and spatially along nutrient enrichment and geoclimatic gradients. Seasonal variation in preferential flow pathways mobilising groundwater-derived DOM were identified as likely controls on the delivery of DOM in the permeable chalk dominated catchment. Steeper S350-400 values and elevated a250:a365 ratios in this catchment suggest material of a lower bulk aromatic C content and molecular weight delivered during the winter months when compared to the summer. DOC:DON ratios were markedly lower in the chalk catchment than the peatland catchment, reflecting the paucity of organic matter within the mineral soils of the chalk landscape, and higher fertiliser application rates. This manuscript highlights that DOM composition varies according to catchment landscape character and hydrological function. PMID:27422728

  11. Diets and habitat analyses of mule deer on the 200 areas of the Hanford Site in southcentral Washington

    International Nuclear Information System (INIS)

    Forty-four food items were identified in the fecal pellets of the mule deer (Odocoileus hemionus hemionus) on three areas of the Hanford Site. Microscopic analysis of plant fragments indicated that bitterbrush was the most common species occurring in the diets of deer from the B-C Cribs area. Russian thistle (Salsola kali) and goldenrod (Solidago sp.) were the most abundant plants found in the fecal pellets collected from B Pond and Gable Mountain Pond habitats, respectively. The similarity in diets among the habitats was low, ranging from 10% to 16%. Preference indices of forage plants among sites were not similar (7% to 19%). The B-C Cribs, B Pond and Gable Mountain Pond habitats were characterized for canopy cover and frequency of occurrence of plant species. Twelve species were sampled in the B-C Cribs and B Pond areas; 22 species were identified on the Gable Mountain site. The most commonly occurring plant was cheatgrass (Bromus tectorum) in all three sites. The similarity in frequency and canopy cover of plants was low among sites. Mule deer inhabiting the Hanford site can serve as a pathway for movement of radioactive material from low-level radioactive waste management areas to man. Maximum levels of 137Cs found in deer pellet groups collected from B Pond and Gable Mountain Pond areas were 100 pCi/g and 128 pCi/g, respectively. Background levels were reported at B-C Cribs area. Maximum 90Sr values found in deer pellets at B Pond were 107 pCi/g and 184 pCi/g at Gable Mountain Pond

  12. WWF Kikori Catchment Developmental Project, Papua New Guinea orchid survey

    NARCIS (Netherlands)

    Clements, M.A.; Harris, W.K.

    2002-01-01

    The World Wildlife Fund (Kikori Catchment Developmental Project, Papua New Guinea) has commenced field surveys of the Orchidaceae in the Lake Kutabu and Mt Bosavi areas of Papua New Guinea. The main purpose of the survey is to get a more accurate assessment of the orchids in the region. In a previou

  13. Hydrological Impacts of Urbanization of Two Catchments in Harare, Zimbabwe

    Directory of Open Access Journals (Sweden)

    Webster Gumindoga

    2014-12-01

    Full Text Available By increased rural-urban migration in many African countries, the assessment of changes in catchment hydrologic responses due to urbanization is critical for water resource planning and management. This paper assesses hydrological impacts of urbanization on two medium-sized Zimbabwean catchments (Mukuvisi and Marimba for which changes in land cover by urbanization were determined through Landsat Thematic Mapper (TM images for the years 1986, 1994 and 2008. Impact assessments were done through hydrological modeling by a topographically driven rainfall-runoff model (TOPMODEL. A satellite remote sensing based ASTER 30 metre Digital Elevation Model (DEM was used to compute the Topographic Index distribution, which is a key input to the model. Results of land cover classification indicated that urban areas increased by more than 600 % in the Mukuvisi catchment and by more than 200 % in the Marimba catchment between 1986 and 2008. Woodlands decreased by more than 40% with a greater decrease in Marimba than Mukuvisi catchment. Simulations using TOPMODEL in Marimba and Mukuvisi catchments indicated streamflow increases of 84.8 % and 73.6 %, respectively, from 1980 to 2010. These increases coincided with decreases in woodlands and increases in urban areas for the same period. The use of satellite remote sensing data to observe urbanization trends in semi-arid catchments and to represent catchment land surface characteristics proved to be effective for rainfall-runoff modeling. Findings of this study are of relevance for many African cities, which are experiencing rapid urbanization but often lack planning and design.

  14. Hydrogeological Characteristics of a Karst Mountainous Catchment in the Northwest of Vietnam

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper presents a preliminary assessment of the hydrogeological characteristics of a karst mountainous catchment, the Suoi Muoi River catchment, in the northwest of Vietnam. The catchment is located at 600 -700 m a.s.1. and covers an area of 284 km. Exposed limestone occupies 32% of the total catchment area. Various types of assessments have been carded out, including geological and hydrogeological field surveys, cave surveys, dye-tracer tests, meteorological and surface water monitoring. Geological studies and cave surveys have identified the most important active cave/conduit systems within the catchment. Although these data are essential, they are insufficient to make a comprehensive appraisal of the hydrologic nature of the catchment under interest. An attempt was made to calculate a global water balance of the catchment, based on short-term (15 months) meteorological and streamfiow records. The results show that, despite the existence of a number of substantial cavern conduit systems, the groundwater system of the catchment is governed by the fracture/fissure matrix. The cavern conduit systems only collect groundwater from the adjacent fracture matrix and/or connect topographically isolated surface watercourses. The groundwater storage of the cavern conduit systems appears to be regionally insignificant in comparison with the governed fracture matrix groundwater system.``

  15. Calibration at regional scale for rainfall-runoff modeling in ungauged catchments.

    Science.gov (United States)

    Montosi, E.; Montanari, A.; Toth, E.; Parajka, J.; Blöschl, G.

    2012-04-01

    The objective of this study is to explore one possible solution to optimise the parameters of rainfall-runoff models in ungauged catchments. We propose a cross-calibration procedure based on the adoption, for selected pairs of catchments, of a unique, space- invariant parameter set, which can be identified by using information that refers to gauged catchments in the same region. A basin in turn in the study region is selected and identified as target catchment and treated as ungauged. We will refer to all the remaining catchments in the same region as the donors. The R-R model is calibrated on each donor in turn, therefore identifying the donor which provides the most reliable parameter set. Then, a similarity measure is elaborated to assist in the selection of the most performing donor catchment, therefore proposing a quantitative criteria to identify the most appropriate information to be used in ungauged conditions. The similarity measure, which depends on geomorphoclimatic behaviours, can be used to identify more than one donor catchment in the case one needs to increase the consistency of the available data-base. We want to analyse the trade-off between assuming the parameters homogeneous in space and adding new information as the cross-calibration evolves. The analysis is performed by referring to the case study of a set of 7 catchments located in Northern Italy.

  16. Karst catchments exhibited higher degradation stress from climate change than the non-karst catchments in southwest China: An ecohydrological perspective

    Science.gov (United States)

    Liu, Meixian; Xu, Xianli; Wang, Dingbao; Sun, Alexander Y.; Wang, Kelin

    2016-04-01

    Karst landform represents about 10% of the continental area and plays key roles in water supplies for almost a quarter of the global population. Knowledge of ecohydrological responses of karst landform to climate change is critical for both water resources management and ecological protection in these regions. This study investigated the effects of karst landform on the elasticity of actual evapotranspiration (derived by the Budyko equation), estimated the contribution of climate change and evaluated the implications, on the basis of 13 typical catchments that have different karst landform coverages in southwest China. Catchment properties, including the vegetation coverage, portion of karst landform (POK), drainage area, surface roughness, mean topographic wetness index, mean slope, and mean aspect, were selected to test the influencing factors for the elasticity of actual evapotranspiration. Results indicate that POK is the most influencing factor for the elasticity of actual evapotranspiration in this region. Moreover, the actual evapotranspiration in karst catchments is more sensitive to precipitation change and less sensitive to the potential evapotranspiration change than that in the non-karst catchments. On the other hand, the contribution of climate change to actual evapotranspiration was generally negative in this region. Furthermore, relatively large negative contributions mainly occurred in the karst-dominated catchments, suggesting that the karst catchments were exposed to higher degradation stress brought by the climate change than that in non-karst catchments.

  17. Fragmentation and connection of frames in collaborative water governance: a case study of river catchment management in Southern Ecuador

    NARCIS (Netherlands)

    Dewulf, A.; Mancero, M.; Cárdenas, G.; Sucozhañay, D.

    2011-01-01

    In collaborative water governance, the variety of frames that actors bring to the discussion constitutes an important challenge. In this study, we analyse the fragmentation and connection of frames in collaborative water governance projects in the Paute catchment and its sub-catchment Tabacay in the

  18. 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...

  19. Organic carbon efflux from a deciduous forest catchment in Korea

    Directory of Open Access Journals (Sweden)

    S. J. Kim

    2010-04-01

    Full Text Available Soil infiltration and surface discharge of precipitation are critical processes that affect the efflux of Dissolved Organic Carbon (DOC and Particulate Organic Carbon (POC in forested catchments. Concentrations of DOC and POC can be very high in the soil surface in most forest ecosystems and their efflux may not be negligible particularly under the monsoon climate. In East Asia, however, there are little data available to evaluate the role of such processes in forest carbon budget. In this paper, we address two basic questions: (1 how does stream discharge respond to storm events in a forest catchment? and (2 how much DOC and POC are exported from the catchment particularly during the summer monsoon period? To answer these questions, we collected hydrological data (e.g., precipitation, soil moisture, runoff discharge, groundwater level and conducted hydrochemical analyses (including DOC, POC, and six tracers in a deciduous forest catchment in Gwangneung National Arboretum in west-central Korea. Based on the end-member mixing analysis of the six storm events during the summer monsoon in 2005, the surface discharge was estimated as 30 to 80% of the total runoff discharge. The stream discharge responded to precipitation within 12 h during these storm events. The annual efflux of DOC and POC from the catchment was estimated as 0.04 and 0.05 t C ha−1 yr−1, respectively. Approximately 70% of the annual organic carbon efflux occurred during the summer monsoon period. Overall, the annual efflux of organic carbon was estimated to be about 10% of the Net Ecosystem carbon Exchange (NEE obtained by eddy covariance measurement at the same site. Considering the current trends of increasing intensity and amount of summer rainfall and the large interannual variability in NEE, ignoring the organic carbon efflux from forest catchments would result in an inaccurate estimation of the carbon sink strength of forest ecosystems in the monsoon

  20. Water displacement by sewer infrastructure in the Grote Nete catchment, Belgium, and its hydrological regime effects

    Directory of Open Access Journals (Sweden)

    D. Vrebos

    2013-06-01

    Full Text Available Urbanization and especially impervious areas, in combination with wastewater treatment infrastructure, can exert several pressures on the hydrological cycle. These pressures were studied for the Grote Nete catchment in Belgium (8.18% impervious area and 3.89% effective impervious area, based on a combination of empirical and model-based approaches. The effective impervious area, combined with the extent of the wastewater collection regions which do not coincide with the natural catchment boundaries, was used as an indicator for the urbanization pressure. Our study revealed changes in the total upstream areas of the subcatchments between −16% and +3%, and in upstream impervious areas between −99% and +64%. These changes lead to important inter-catchment water transfers. Based on simulations with a physically-based and spatially-distributed hydrological catchment model, profound impacts of effective impervious area on infiltration and runoff were found. The model results show that the changes in impervious areas and related water displacements in and between catchments due to the installation of the wastewater treatment infrastructure severely impacted low flows, peak flows and seasonal trends. They moreover show that it is difficult, but of utmost importance, to incorporate these pressures and artificial processes in an accurate way during the development of hydrological models for urbanized catchments.

  1. Water displacement by sewer infrastructure in the Grote Nete catchment, Belgium, and its hydrological regime effects

    Science.gov (United States)

    Vrebos, D.; Vansteenkiste, T.; Staes, J.; Willems, P.; Meire, P.

    2013-06-01

    Urbanization and especially impervious areas, in combination with wastewater treatment infrastructure, can exert several pressures on the hydrological cycle. These pressures were studied for the Grote Nete catchment in Belgium (8.18% impervious area and 3.89% effective impervious area), based on a combination of empirical and model-based approaches. The effective impervious area, combined with the extent of the wastewater collection regions which do not coincide with the natural catchment boundaries, was used as an indicator for the urbanization pressure. Our study revealed changes in the total upstream areas of the subcatchments between -16% and +3%, and in upstream impervious areas between -99% and +64%. These changes lead to important inter-catchment water transfers. Based on simulations with a physically-based and spatially-distributed hydrological catchment model, profound impacts of effective impervious area on infiltration and runoff were found. The model results show that the changes in impervious areas and related water displacements in and between catchments due to the installation of the wastewater treatment infrastructure severely impacted low flows, peak flows and seasonal trends. They moreover show that it is difficult, but of utmost importance, to incorporate these pressures and artificial processes in an accurate way during the development of hydrological models for urbanized catchments.

  2. Morphology, Geology and Water Quality Assessment of Former Tin Mining Catchment

    OpenAIRE

    Muhammad Aqeel Ashraf; Mohd. Jamil Maah; Ismail Yusoff

    2012-01-01

    Bestari Jaya, former tin mining catchment covers an area of 2656.31 hectares comprised of four hundred and forty-two different-size lakes and ponds. The present study area comprise of 92 hectares of the catchment that include four large size lakes. Arc GIS version 9.2 used to develop bathymetric map, Global Positioning System (GPS) for hydrographical survey and flow meter was utilized for water discharge analysis (flow routing) of the catchment. The water quality parameters (pH, temperature, ...

  3. Stratification and analysis of housing indicators of rural areas of Isfahan province using factor and cluster analyses

    Directory of Open Access Journals (Sweden)

    S. E. Seidaiy

    2013-01-01

    Full Text Available Extended abstract1-IntroductionNowadays housing and its related issues are considered as a global issue and planners and policy makers in different countries are trying to solve its problems (Buckley, et al., 2005:237. Among different factors involved in rural settlement structures housing is one of the most important ones (Sartipipor, 2010:125. In Iran, the issue of rural housing, on different aspects, has been affected by urban housing. Despite the efforts made to improve it, and giving priority to it in rural development programs, housing provision has always been one of the problems of many people, especially low-income families in rural areas.Non-availability of suitable and standard housing, which is an index of rural development, causes psychological and social damage in rural people's lives, interruption and irregularity in rural housing structures, and ultimately social and economic crises in national level. Therefore, the issue of appropriate planning and policy making for housing and access to a desirable model for rural residents is a major concern of rural planners (Lotfi, 2010:105. One of the important ways of having knowledge of rural condition in the process of rural planning is the use of rural housing indicators (Azizi, 2006:26.2- Theoretical basesRural housing is a coordinated structure consistent with economic, social and cultural structure of rural area that has essential differences with urban housing. In fact, the expectations of two urban and rural societies from housing are not the same. In cities, nowadays, houses mostly have the role of dormitory or resort, while in rural areas people expect more from the housing. For a rural person, housing, besides being a resort unit, is also considered as an economic functional unit (Papoliyazdi, 1994:490. Based on the policies enforced and the amount of government intervention in the housing issue, there are two distinct lines of thought among housing scholars and researchers

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

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — 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...

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

    Data.gov (United States)

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

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

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — 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....

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

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set represents the estimated area of level 3 ecological landscape regions (ecoregions), as defined by Omernik (1987), compiled for every catchment of...

  8. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: Surficial Geology

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — 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...

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

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — 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...

  10. 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

  11. Dissolved nutrient exports from natural and human-impacted Neotropical catchments

    DEFF Research Database (Denmark)

    Gücker, Björn; Silva, Ricky C. S.; Graeber, Daniel;

    2016-01-01

    Aim Neotropical biomes are highly threatened by land-use changes, but the catchment-wide biogeochemical effects are poorly understood. Here, we aim to compare exports of dissolved nitrogen (N) and phosphorus (P) from natural and human-impacted catchments in the Neotropics. Location Neotropics....... Methods We measured streamwater nutrient concentrations and exports in 20 south-eastern Brazilian catchments with different land uses (natural Cerrado/semi-deciduous forest, pasture, intensive agriculture and urban areas) and conducted a meta-analysis on nutrient exports from Neotropical catchments, both...... natural and human-impacted. Results Organic forms dominated dissolved nutrient exports in central/south-east Brazil in both natural and human-dominated catchments. Our meta-analysis suggests that there is wide geographic variability in the natural dominance of organic versus inorganic nutrient exports...

  12. Forest fire impact on the hydrological response in small catchment of NW Spain

    Directory of Open Access Journals (Sweden)

    J. Canceio-González

    2013-05-01

    Full Text Available Hydrological studies were carried out in two catchments (burnt and unburned, to determine the processes related to the streamflow changes and the possible effects on the runoff coefficients produced by a forest fire in the summer of 2007, which affected 50% of the area of one of the catchments. Comparative analysis of the changes in the monthly streamflow values revealed that during the wettest months, the runoff was higher in the burnt catchment during the first two years, and was very similar in both catchments during the third year. Calculation of the annual runoff coefficient confirmed these findings and showed that the differences between the coefficients in the catchments were negligible in the final year. In both cases, this can be explained by regeneration of the vegetation after fire.

  13. ATTEMPT TO ANALYSE THE DIFFERENCES BETWEEN EARLY MEDIEVAL FEMALE SILVER JEWELLERY FROM THE SOUTHWESTERN AND SOUTHEASTERN AREA OF POLAND

    Directory of Open Access Journals (Sweden)

    Dagmara Krol

    2015-09-01

    Full Text Available The article is an attempt to analyze female silver jewellery produces and used during Early Middle Ages in regions of southeastern and southwestern Poland. Those regions correspond to the area of nowadays Poland, respectively southwestern voivodeships: Dolnoslaskie, Slaskie, Opolskie, Malopolskie and southeastern voivodeships: Podkarpackie and Lubuskie.The presented work deals with similarities and differences in quality and types of jewellery from those regions. The analysis focuses on silver items found in settlements, cemeteries and hoards. The recovered female jewellery highlights the divergence between east, under influence of culture from Byzantine Empire, and west.Thanks to described archeological relics, the southern region of present Poland can be easily divided into two distinguishable parts representing different cultures.

  14. Resistance and Seakeeping Numerical Performance Analyses of a Semi-Small Waterplane Area Twin Hull at Medium to High Speeds

    Institute of Scientific and Technical Information of China (English)

    Giuliano Vernengo; Dario Bruzzone

    2016-01-01

    The hydrodynamic analysis of a new semi-small waterplane area twin hull (SWATH) suitable for various applications such as small and medium size passenger ferries is presented. This may be an attractive crossover configuration resulting from the merging of two classical shapes: a conventional SWATH and a fast catamaran. The final hull design exhibits a wedge-like waterline shape with the maximum beam at the stern; the hull ends with a very narrow entrance angle, has a prominent bulbous bow typical of SWATH vessels, and features full stern to arrange waterjet propellers. Our analysis aims to perform a preliminary assessment of the hydrodynamic performance of a hull with such a complex shape both in terms of resistance of the hull in calm water and seakeeping capability in regular head waves and compare the performance with that of a conventional SWATH. The analysis is performed using a boundary element method that was preliminarily validated on a conventional SWATH vessel.

  15. Partial reconfiguration of a peripheral in an FPGA-based SoC to analyse performance-area behaviour

    Science.gov (United States)

    Cardona, Andres; Guo, Yi; Ferrer, Carles

    2011-05-01

    Systems on Chip (SoC) are present in a wide range of applications. This diversity in addition with the quantity of critical variables involved in their design process becomes it as a great challenging topic. FPGAs have consolidated as a preferred device to develop and prototype SoCs, and consequently Partial Reconfiguration (PR) has gained importance in this approach. Through PR it is possible to have a section of the FPGA operating, while other section is disabled and partially reconfigured to provide new functionality. In this way hardware resources can be time-multiplexed and therefore it is possible to reduce size, cost and power. In this case we focus on the implementation of a SoC, in an FPGA-based board, with one of its peripherals being a reconfigurable partition (RP). Inside this RP different hardware modules defined as reconfigurable modules (RM) can be configured. Thus, the system is suitable to have different hardware configurations depending on the application needs and FPGA limitations, while the rest of the system continues working. To this end a MicroBlaze soft-core processor is used in the system design and a Virtex-5 FPGA board is utilized to its implementations. A remote sensing application is used to explore the capabilities of this approach. Identifying the section(s) of the application suitable of being time-shared it is possible to define the RMs to place inside the RP. Different configurations were carried out and measurements of area were taken. Preliminary results of the performance-area utilisation are presented to validate the improvement in flexibility and resource usage.

  16. Controls of catchments` sub-storage contributions to dynamic water quality patterns in the stream network

    Science.gov (United States)

    Schuetz, Tobias; Maike Hegenauer, Anja

    2016-04-01

    Water quality is usually observed either continuously at a few stations within a catchment or with few snapshot sampling campaigns throughout the whole stream network. Although we know that the depletion of catchment sub-storages can vary throughout the stream network according to their actual water content (spatial variability of actual storage conditions can be caused amongst others by unevenly distributed rainfall, storage size or spatial differences in soil characteristics and land use), we know little about the impact of this process on spatial water quality patterns. For summer low flow recession periods, when stream water composition can be crucial for aquatic ecosystem conditions and the exceedance of water quality thresholds, knowledge on the controls of the dynamic interplay of catchment storages and stream water composition might improve water quality management and the implementation of corresponding mitigation measures. We studied this process throughout the stream network of a first-order agricultural headwater catchment in south-western Germany during two summer low flow recession periods. The underlying geology of the study area is a deep layer of aeolian loess, whilst the dominating soil is a silty calcaric regosol with gleizations in the colluvium. The land use in the catchment is dominated by viniculture (63 %) and arable crops (18 %). Due to the dense drainpipe network within the catchment we could identify 12 sub-catchments contributing during summer low flow recession periods to total stream discharge. We continuously observed discharge, electrical conductivity and water temperatures for 8 of the sub-catchments and at the catchment outlet. This data set was accomplished by 10 snapshot campaigns where we sampled for water temperatures, electrical conductivity, major ions, pH and O2 throughout the stream network. Using either discharge concentration relationships or time dependent functions, we derived continuous export rates for all measures in

  17. Sediment yield and connectivity in a gullied sandy catchment

    Science.gov (United States)

    Lucía, Ana; Francisco Martín-Duque, José; Laronne, Jonathan B.; Ángel Sanz-Santos, Miguel

    2014-05-01

    Badland areas are considered to have high connectivity of sediment at the catchment scale; however, little is known about processes occurring in gullies and badlands developed in sands. This type of gullies is quite common in the Central-Eastern Iberian Peninsula and is associated with historic mining. The sandy badlands also appear in both abandoned and traditionally reclaimed mines, generating on- and offsite environmental effects. Our aim is to quantify the rates of the different processes occurring in the sandy gullied catchments, as well as their coupling and connectivity at a catchment scale. This may allow application to improve reclamation practice in mines and quarries located in sandy materials. The study site is a small (1.32 ha) gullied catchment, the Barranca de los Pinos, which is located in the Northern Piedmont of the Guadarrama Mountains (Central Spain). The catchment area has been divided into Homogeneous Response Units (HRUs) attending to the dominant active process . The sediment produced in the different HRUs has been monitored by a variety of methods: repeat Terrestrial Laser Scanning of high gradient slopes, closed microplots in low gradient slopes and automatic (Reid type) slot bedload samplers and siphon samplers to monitor suspended sediment transport in the channel. During the 2010-11 monitoring period the sediment yield due to gravitational movements in high gradient slopes varied from 20 to 200 kg m-2y-1. In the low gradient slopes the splash and non-concentrated runoff generated 0.1 - 6 kg m-2y-1,while the channel yielded 7.44 ± 1.08 kg m-2y-1 with a very high proportion (>70%) of bedload. Despite the difficulties of extrapolating and comparing the results obtained at different spatial and temporal resolutions, annual patterns of erosion and transport of sediments within the sandy gullied catchments have been identified. These confirm that the transport of sediment in this catchment is limited by the capacity of flow events to

  18. Managing erosion, sediment transport and water quality in drained peatland catchments

    OpenAIRE

    Marttila, H.

    2011-01-01

    Abstract Peatland drainage changes catchment conditions and increases the transport of suspended solids (SS) and nutrients. New knowledge and management methods are needed to reduce SS loading from these areas. This thesis examines sediment delivery and erosion processes in a number of peatland drainage areas and catchments in order to determine the effects of drainage on sediment and erosion dynamics and mechanics. Results from studies performed in peat mining, peatland forestry and distu...

  19. Water displacement by sewer infrastructure in the Grote Nete catchment, Belgium, and its hydrological regime effects

    OpenAIRE

    Vrebos, D.; T. Vansteenkiste; J. Staes; Willems, P; P. Meire

    2014-01-01

    Urbanization and especially increases in impervious areas, in combination with the installation of wastewater treatment infrastructure, can impact the runoff from a catchment and river flows in a significant way. These effects were studied for the Grote Nete catchment in Belgium based on a combination of empirical and model-based approaches. Effective impervious area, combined with the extent of the wastewater collection regions, was considered as an indicator for urbanization pressure....

  20. Urbanization increased metal levels in lake surface sediment and catchment topsoil of waterscape parks

    International Nuclear Information System (INIS)

    Lake surface sediment is mainly derived from topsoil in its catchment. We hypothesized that distribution of anthropogenic metals would be homogenous in lake surface sediment and the lake's catchment topsoil. Anthropogenic metal distributions (cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn)) in fourteen waterscape parks were investigated in surface sediments and catchment topsoils and possible source homogeneity was tested using stable Pb isotopic ratio analysis. The parks were located along an urbanization gradient consisting of suburban (SU), developing urban (DIU), developed urban (DDU), and central urban core (CUC) areas in Shanghai, China. Results indicated that surface lake sediments and catchment topsoils in the CUC parks were highly contaminated by the investigated anthropogenic metals. Total metal contents in surface sediment and topsoil gradually increased along the urbanization gradient from the SU to CUC areas. Generally, the surface sediments had greater total metal contents than their catchment topsoils. These results suggest that urbanization drives the anthropogenic metal enrichment in both surface sediment and its catchment topsoil in the waterscape parks. Soil fine particles (< 63 μm) and surface sediments had similar enrichment ratios of metals, suggesting that surface runoff might act as a carrier for metals transporting from catchment to lake. Stable Pb isotope ratio analysis revealed that the major anthropogenic Pb source in surface sediment was coal combustion as in the catchment topsoil. Urbanization also correlated with chemical fractionation of metals in both surface sediment and catchment topsoil. From the SU to the CUC parks, amounts of labile metal fractions increased while the residual fraction of those metals remained rather constant. In short, urbanization in Shanghai drives anthropogenic metal distribution in environmental matrices and the sources were homogenous. -- Highlights: ► Obvious urbanization effect on metal

  1. Urbanization increased metal levels in lake surface sediment and catchment topsoil of waterscape parks

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hong-Bo [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Yu, Shen, E-mail: syu@iue.ac.cn [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Li, Gui-Lin [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Liu, Yi; Yu, Guang-Bin [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Deng, Hong [Department of Environmental Sciences, Tiantong National Station of Forest Ecosystem, Key Laboratory of Urbanization and Ecological Restoration, East China Normal University, Shanghai 200062 (China); Wu, Sheng-Chun [State Key Laboratory in Marine Pollution, Biology and Chemistry Department, City University of Hong Kong, Hong Kong (China); Wong, Ming-Hung [Croucher Institute for Environmental Sciences, Hong Kong Baptist University, Hong Kong (China)

    2012-08-15

    Lake surface sediment is mainly derived from topsoil in its catchment. We hypothesized that distribution of anthropogenic metals would be homogenous in lake surface sediment and the lake's catchment topsoil. Anthropogenic metal distributions (cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn)) in fourteen waterscape parks were investigated in surface sediments and catchment topsoils and possible source homogeneity was tested using stable Pb isotopic ratio analysis. The parks were located along an urbanization gradient consisting of suburban (SU), developing urban (DIU), developed urban (DDU), and central urban core (CUC) areas in Shanghai, China. Results indicated that surface lake sediments and catchment topsoils in the CUC parks were highly contaminated by the investigated anthropogenic metals. Total metal contents in surface sediment and topsoil gradually increased along the urbanization gradient from the SU to CUC areas. Generally, the surface sediments had greater total metal contents than their catchment topsoils. These results suggest that urbanization drives the anthropogenic metal enrichment in both surface sediment and its catchment topsoil in the waterscape parks. Soil fine particles (< 63 {mu}m) and surface sediments had similar enrichment ratios of metals, suggesting that surface runoff might act as a carrier for metals transporting from catchment to lake. Stable Pb isotope ratio analysis revealed that the major anthropogenic Pb source in surface sediment was coal combustion as in the catchment topsoil. Urbanization also correlated with chemical fractionation of metals in both surface sediment and catchment topsoil. From the SU to the CUC parks, amounts of labile metal fractions increased while the residual fraction of those metals remained rather constant. In short, urbanization in Shanghai drives anthropogenic metal distribution in environmental matrices and the sources were homogenous. -- Highlights: Black-Right-Pointing-Pointer Obvious

  2. Pesticide uses and transfers in urbanised catchments.

    Science.gov (United States)

    Blanchoud, Hélène; Farrugia, Frédéric; Mouchel, Jean Marie

    2004-05-01

    An investigation on herbicide uses in two semi-urban catchments was performed simultaneously with sampling campaigns at six stations inside both watersheds from April to July 1998. Urban uses of herbicides exceeded agricultural uses, and transfer coefficients were also higher in urban areas. Therefore, the most used product in urban areas (diuron) was by far the most contaminating product. Householders accounted for 30% of all uses. The highest measured diuron concentration in water surface was 8.7 microg l(-1) due to its use on impervious surfaces. Compared to EEC standards for drinking water production (0.1 microg l(-1)), it is clear that suburban uses of herbicides may severely endanger drinking water production from river water.

  3. Hill slope unsaturated flowpaths and soil moisture variability in a Forested Catchment in Southwest China

    OpenAIRE

    Sørbotten, Lars-Erik

    2011-01-01

    Forested catchments in subtropical southwest China are important sites for nitrogen, primarily due to denitrification. Denitrification depends strongly on soil moisture content and the residence time of soil water. Both depend on the hydrological properties of the soils. In this study we investigated the soil hydrological properties and water flow paths on a hill slope in the TieShanPing catchment around 25 kilometres north-east of Chongqing. Soils were sampled for analyses of water retention...

  4. Characteristics of Non-point-source Phosphorus Losses in Some Representative Land-use Sub-catchments in the Hilly Area of Purple Soil%紫色丘陵区典型小流域非点源磷迁移特征

    Institute of Scientific and Technical Information of China (English)

    沈茜; 唐家良; 朱波

    2015-01-01

    通过对居民点、林地、坡耕地等土地利用类型的小型集水区(亚流域)径流磷形态与通量的定位监测,研究了紫色丘陵典型小流域的非点源磷流失特征。结果表明,居民点在降雨量4 mm即可产流,林地与坡耕地的产流临界降雨量为20 mm。居民点的降雨径流响应迅速,径流与降雨峰值基本同步;林地和坡耕地产流时间延迟,径流峰值较降雨延迟20~120 min。居民点、坡耕地和林地的次降雨平均径流深分别为22.4、12.3、9.5 mm,径流系数分别为0.36、0.17和0.09,泥沙流失量分别为136.2、73.5和48.6 kg/hm2。居民点和林地径流的总磷(Total P-TP)、颗粒态磷(Particulate P-PP)浓度在径流过程中迅速达到峰值后陡然下降;坡耕地径流的TP、PP浓度呈多峰变化。居民点径流的可溶性磷(Dissolved P-DP)浓度随径流量增大而减少;林地径流的DP浓度逐渐增加;坡耕地DP、磷酸盐(PO3-4-P)浓度较低且波动较小。居民点小雨、中雨、大雨和暴雨等雨型下的 TP流失负荷分别为42.6、136.3、190.0、1245.6 g/hm2,平均负荷为403.6 g/hm2,林地与坡耕地在中雨、大雨和暴雨等雨型下的TP流失负荷分别为3.5、3.9、90.6和6.6、10.2、210.6 g/hm2,二者的平均负荷为32.7和75.8 g/hm2。降雨量越大,磷流失负荷越高,暴雨条件下的TP流失负荷最高。居民点的磷流失负荷远高于坡耕地和林地,表明居民点的径流污染是非点源污染控制的关键源。%Phosphorus forms and fluxes via hydrological pathways in typical rainfall events from different land uses in the hilly area of purple soil had been conducted by in-situ monitoring in some sub-catchments so as to understand“hotspot”and “critical time”for control of non-point-source pollution of phosphorus in a catchment.Rainfall-run-off process along with sediment yield,total phosphorus

  5. Runoff predictions in ungauged catchments in southeast Tibetan Plateau

    Science.gov (United States)

    Li, Fapeng; Zhang, Yongqiang; Xu, Zongxue; Liu, Changming; Zhou, Yanchun; Liu, Wenfeng

    2014-04-01

    The Tibetan Plateau (TP) plays a key role on both hydrology and climate for southern and eastern Asia. Improving runoff predictions in ungauged catchments in the TP is critical for surface water hydrology and water resources management in this region. However, a detailed runoff prediction study in this region has not been reported yet. To fill the gap, this study evaluates two regionalization approaches, spatial proximity and physical similarity, for predicting runoff using two rainfall-runoff models (SIMHYD and GR4J). These models are driven by meteorological inputs from eight large non-nested catchments (4000-50,000 km2) in the Yarlung Tsangpo River basin located in southeast TP. For each catchment, the two models are calibrated using data from the first two-thirds of the observation period and validated over the remaining period. The calibrated and validated Nash-Sutcliffe Efficiency of monthly runoff (NSE) varies from 0.73 to 0.93 for the SIMHYD model, and are similar to or slightly better than those obtained for the GR4J model. The incorporation of snowfall-snowmelt processes into the rainfall-runoff models does not noticeably improve the runoff predictions in the study area. The main reason is that monthly runoff is dominated by summer precipitation and snowfall in winter accounts for a small percentage (less than 14%). The results from both models show that the spatial proximity approach marginally outperforms the physical similarity approach and both approaches are better than random selection of a donor catchment. This is consistent with recent regionalization studies carried out in Europe and Australia. The study suggests that conceptual rainfall-runoff models are powerful and simple tools for monthly runoff predictions in large catchments in southeast TP, and incorporation of more catchments into regionalization can further improve prediction skills.

  6. Applications of optical spectroscopy and stable isotope analyses to organic aerosol source discrimination in an urban area

    Science.gov (United States)

    Mladenov, N.; Alados-Arboledas, L.; Olmo, F. J.; Lyamani, H.; Delgado, A.; Molina, A.; Reche, I.

    2011-02-01

    Understanding the chemical character of organic aerosols is extremely important for evaluating their role in climate forcing and human respiratory health. Aerosol columnar properties retrieved by sun photometry represent a large dataset of information about the physical and light absorbing and scattering properties of the total aerosol, but lack more detailed chemical information about the organic fraction of atmospheric particulate matter. To obtain additional information about relationships between organic aerosol sources and columnar properties, we simultaneously examined stable isotope properties of PM 10 aerosols from urban (Granada, Spain) and remote (Sierra Nevada, Spain) sites and diesel exhaust, spectroscopic properties of water soluble organic carbon (WSOC) of PM 10 aerosols, and sun photometry measurements. We demonstrated that C and N stable isotopes and parameters from UV-vis and fluorescence spectroscopy are able to discriminate between aerosols receiving substantial fossil fuel pollution and those influenced by Saharan dust in an urban area. More depleted δ 13C was associated with low asymmetry parameter, g λ, and high values of the spectral slope ratio, S R, were associated with high effective radius, typical of pollution situations. The humification index (HIX), used predominantly to evaluate the degree of organic matter humification, was significantly related to g λ and the radius of fine mode particles, r f, and may reflect aging of the Saharan dust-influenced aerosols. Parallel factor analysis (PARAFAC) modeling identified a fluorescent component (C3) with a spectrum similar to that of naphthalene, which was significantly related to g λ and r f. The diesel exhaust sample represented a pollution end-member, with the lightest δ 13C value (-26.4‰), lowest S R (0.95), lowest HIX (2.77) and highest %C3 (20%) of all samples.

  7. 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

  8. Runoff scenarios of the Ötz catchment (Tyrol, Austria) considering climate change driven changes of the cryosphere

    Science.gov (United States)

    Helfricht, Kay; Schneeberger, Klaus; Welebil, Irene; Schöber, Johannes; Huss, Matthias; Formayer, Herbert; Huttenlau, Matthias; Schneider, Katrin

    2014-05-01

    The seasonal distribution of runoff in alpine catchments is markedly influenced by the cryospheric contribution (snow and ice). Long-term climate change will alter these reservoirs and consequently have an impact on the water balance. Glacierized catchments like the Ötztal (Tyrol, Austria) are particularly sensitive to changes in the cryosphere and the hydrological changes related to them. The Ötztal possesses an outstanding role in Austrian and international cryospheric research and reacts sensitive to changes in hydrology due to its socio-economic structure (e.g. importance of tourism, hydro-power). In this study future glacier scenarios for the runoff calculations in the Ötztal catchment are developed. In addition to climatological scenario data, glacier scenarios were established for the hydrological simulation of future runoff. Glacier outlines and glacier surface elevation changes of the Austrian Glacier Inventory were used to derive present ice thickness distribution and scenarios of glacier area distribution. Direct effects of climate change (i.e. temperature and precipitation change) and indirect effects in terms of variations in the cryosphere were considered for the analysis of the mean runoff and particularly flood frequencies. Runoff was modelled with the hydrological model HQSim, which was calibrated for the runoff gauges at Brunau, Obergurgl and Vent. For a sensitivity study, the model was driven by separate glacier scenarios. Keeping glacier area constant, variable climate input was used to separate the effect of climate sensitivity. Results of the combination of changed glacier areas and changed climate input were subsequently analysed. Glacier scenarios show first a decrease in volume, before glacier area shrinks. The applied method indicates a 50% ice volume loss by 2050 relative to today. Further, model results show a reduction in glacier volume and area to less than 20% of the current ice cover towards the end of the 21st century. The effect

  9. Discharge Water Quality Models of Storm Runoff in a Catchment

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The relationships between the water qualities of nitrogen and phosphorous contents in the discharge water and the discharge of storm runoff of an experimental catchment including terraced paddy field are analyzed based on experiment results of the catchment. By summarizing the currently related research on water quality models, the water quality models of different components of storm runoff of the catchment are presented and verified with the experiment data of water quality analyses and the corresponding discharge of the storm runoffs during 3 storms. Through estimating the specific discharge of storm runoff, the specific load of different components of nitrogen and phosphorus in the discharge water of the catchment can be forecasted by the models. It is found that the mathematical methods of linear regression are very useful for analysis of the relationship between the concentrations of nitrogen and phosphorus and the water discharge of storm runoff. It is also found that the most content of the nitrogen (75%) in the discharge water is organic, while half of the content (49%) of phosphorus in the discharge water is inorganic.

  10. The ethics of socio-ecohydrological catchment management: towards hydrosolidarity

    Science.gov (United States)

    Falkenmark, M.; Folke, Carl

    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.

  11. Soil Chemistry 1983-86 at the Rain Project Catchments

    OpenAIRE

    Lotse, E.G.; Wright, R.

    1989-01-01

    The aim of the rain project is to explain the effects of changed acid deposition on soils and waters. This report presents results from chemical and physical analyses of soil samples collected yearly 1984-1986 at the rain project catchments at Sogndal and Risdalsheia. Estimates of historical weathering rates based on total elemental analysis of soil and bedrock are 295 and 12 meq/m"/yr at Sogndal and Risdalsheia, respectively. Of the key chemical parameters measured only absorbed sulfate show...

  12. 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.

  13. Modelling Pesticide Leaching At Column, Field and Catchment Scales I. Analysis of Soil Variability At Field and Catchment Scales

    Science.gov (United States)

    Gärdenäs, A.; Jarvis, N.; Alavi, G.

    The spatial variability of soil characteristics was studied in a small agricultural catch- ment (Vemmenhög, 9 km2) at the field and catchment scales. This analysis serves as a basis for assumptions concerning upscaling approaches used to model pesticide leaching from the catchment with the MACRO model (Jarvis et al., this meeting). The work focused on the spatial variability of two key soil properties for pesticide fate in soil, organic carbon and clay content. The Vemmenhög catchment (9 km2) is formed in a glacial till deposit in southernmost Sweden. The landscape is undulating (30 - 65 m a.s.l.) and 95 % of the area is used for crop production (winter rape, winter wheat, sugar beet and spring barley). The climate is warm temperate. Soil samples for or- ganic C and texture were taken on a small regular grid at Näsby Farm, (144 m x 144 m, sampling distance: 6-24 m, 77 points) and on an irregular large grid covering the whole catchment (sampling distance: 333 m, 46 points). At the field scale, it could be shown that the organic C content was strongly related to landscape position and height (R2= 73 %, p organic C content of hollows in the landscape is so high that they contribute little to the total loss of pesticides (Jarvis et al., this meeting). Clay content is also related to landscape position, being larger at the hilltop locations resulting in lower near-saturated hydraulic conductivity. Hence, macropore flow can be expected to be more pronounced (see also Roulier & Jarvis, this meeting). The variability in organic C was similar for the field and catchment grids, which made it possible to krige the organic C content of the whole catchment using data from both grids and an uneven lag distance.

  14. Catchment controls on water temperature and the development of simple metrics to inform riparian zone management

    Science.gov (United States)

    Johnson, Matthew; Wilby, Robert

    2015-04-01

    Water temperature is a key water quality parameter and is critical to aquatic life Therefore, rising temperatures due to climate and environmental change will have major consequences for river biota. As such, it is important to understand the environmental controls of the thermal regime of rivers. The Loughborough University TEmperature Network (LUTEN) consists of a distributed network of 25 sites along 40 km of two rivers in the English Peak District, from their source to confluence. As a result, the network covers a range of hydrological, sedimentary, geomorphic and land-use conditions. At each site, air and water temperature have been recorded at a 15-minute resolution for over 4 years. Water temperature is spatially patchy and temporally variable in the monitored rivers. For example, the annual temperature range at Beresford Dale is over 18° C, whereas 8 km downstream it is less than 8° C. This heterogeneity leads to some sites being more vulnerable to future warming than others. The sensitivity of sites to climate was quantified by comparing the parameters of logistic regression models, constructed at each site, that relate water temperature to air temperature. These analyses, coupled with catchment modelling suggest that reaches that are surface-water dominated with minimal shade and relatively low water volumes are most susceptible to warming. Such reaches tended to occur at intermediate distances from rivers source in the monitored catchments. Reaches that were groundwater dominated had relatively stable thermal regimes, which were relatively unaffected by inter-annual changes in climatic conditions. Such areas could provide important thermal refuge to many organisms, which is supported by monitoring of the invertebrate community in the catchment. The phenology (i.e. timing of life events) of some species remained consistent between years in a river reach with a stable thermal regime, but changed markedly in other areas of the river. Consequently, areas

  15. Testing the applicability of morphometric characterisation in discordant catchments to ancient landscapes: A case study from southern Africa

    Science.gov (United States)

    Richardson, J. C.; Hodgson, D. M.; Wilson, A.; Carrivick, J. L.; Lang, A.

    2016-05-01

    The ancient landscapes south of the Great Escarpment in southern Africa preserve large-scale geomorphological features despite their antiquity. This study applies and evaluates morphometric indices (such as hypsometry, long profile analysis, stream gradient index, and linear/areal catchment characteristics) to the Gouritz catchment, a large discordant catchment in the Western Cape. Spatial variation of morphometric indices were assessed across catchment (trunk rivers) and subcatchment scales. The hypsometric curve of the catchment is sinusoidal, and a range of curve profiles are evident at subcatchment scale. Hypsometric integrals do not correlate to catchment properties such as area, circularity, relief, and dissection; and stream length gradients do not follow expected patterns, with the highest values seen in the mid-catchment areas. Rock type variation is interpreted to be the key control on morphometric indices within the Gouritz catchment, especially hypsometry and stream length gradient. External controls, such as tectonics and climate, were likely diminished because of the long duration of catchment development in this location. While morphometric indices can be a useful procedure in the evaluation of landscape evolution, this study shows that care must be taken in the application of morphometric indices to constrain tectonic or climatic variation in ancient landscapes because of inherited tectonic structures and signal shredding. More widely, we consider that ancient landscapes offer a valuable insight into long-term environmental change, but refinements to geomorphometric approaches are needed.

  16. Lessons learned from integrated hydrological modeling of ephemeral catchments with different land uses

    Science.gov (United States)

    Camporese, Matteo; Dean, Joshua; Daly, Edoardo

    2016-04-01

    Land use, in particular tree cover, has a strong influence on evapotranspiration (ET) and thus a large effect on the water budget of ephemeral catchments in arid and semi-arid climates. Unfortunately, the dearth of medium to long-term experimental observations in such areas limits the understanding of the interplay between catchment geology, land use, and climate in driving catchment water balance. Here we use four years (2011-2014) of rainfall, streamflow, and groundwater level measurements to estimate the water balance components in two small, adjacent, ephemeral catchments in a semi-arid region of south-eastern Australia; one catchment was predominantly covered with a eucalypt plantation established in July 2008 and the other was dedicated to grazing pasture. The integrated hydrological model CATHY (CATchment HYdrology) was calibrated against the data in the two catchments using streamflow and groundwater level observations in 2011; the data in the following years (2012-2014) were used for the model validation. The model was able to adequately reproduce the periods of flow in both catchments in all years, although streamflow and groundwater levels were better reproduced in the pasture than in the plantation. This can partly be attributed to the root growth of the trees, which is difficult to estimate; the declining water storage in the eucalypt catchment could only be obtained when including a simple model of root growth dynamics. Other sources of uncertainty could be due to an imperfect description of the surface topography and bedrock geology, which prevent us from accurately reproducing the effects of the tree furrows and subsurface wetness connectivity. The water balances estimated from both data and model showed a significant increase in ET in the eucalypt plantation catchment at the expense of groundwater storage: ET accounted for 95-104% of rainfall in the pasture catchment and 104-119% in the eucalypt catchment across the four years studied. However, the

  17. Catchment Prediction In Changing Environments (CAPICHE): A Model Inter-Comparison Experiment

    Science.gov (United States)

    Hutton, Christopher; Nijzink, Remko; Pechlivanidis, Ilias; Capell, René; Wagener, Thorsten; Freer, Jim; Han, Dawei; Hrachowitz, Markus; Arheimer, Berit

    2016-04-01

    In order to improve societal resilience to the impacts of changes in climate and land-use, improved understanding of how catchments respond to changing forcing conditions is required. Such understanding may help better identify the range of effective interventions to improve overall integrated catchment management. For example, re-foresting catchment headwaters may reduce high flows, but also reduce low flows through increased evapotranspiration, creating a potential trade-off that needs to be reliably understood when considering benefits for both water supply and flood mitigation. Catchment modelling may be useful to inform such management decisions by simulating future forcing changes, so that we can assess the relative benefits of different catchment management scenarios. However, numerical models are known to be uncertain, and their ability to simulate future change is compromised by the fact that model parameters can show non-stationary and compensatory effects for different forcing conditions, notwithstanding errors and uncertainties in the future forcings themselves. In order to first identify, and second develop the most appropriate models to simulate catchments under environmental change, we argue that model inter-comparisons are required that move beyond a simple comparison of predictive performance alone, towards a controlled comparison of how different models simulate change. We present the development of a methodology for model inter-comparison under changing forcings to analyse, in this case, how models simulate landscape change, built upon time-varying sensitivity analysis of model parameters. First, for a given catchment, hydrologic signatures are calculated over consecutive windows covering the period of forcing change to analyse how the catchment responds hydrologically to change. Then, each model is calibrated to each window, and within each window, to each signature, which allows us to analyse the time-varying relationship between catchment

  18. Analysis of financial measures in the energy area; Analyse finanzieller Massnahmen im Energiebereich: Theoretische Reflexion der Wirkungsweise und Auswertung empirischer Studien

    Energy Technology Data Exchange (ETDEWEB)

    Rieder, S.; Haefeli, U.

    2008-10-15

    This final report for Swiss Federal Office of Energy (SFOE) analyses financial measures that can be taken in the energy area. Based on 17 years of experience with the use of financial measures for the support of energy policy in Switzerland, the mechanisms involved and the effects obtained are discussed. Financial measures are looked at in the light of theoretical economics and applied psychology. The so-called 'deadweight' effect, i.e. that part of activities that would have taken place anyway, is looked at in detail. Finally, the importance of measures is examined and the strengths and weaknesses of financial measures and subvention mechanisms are commented on.

  19. Evidence of viral dissemination and seasonality in a Mediterranean river catchment: Implications for water pollution management.

    Science.gov (United States)

    Rusiñol, Marta; Fernandez-Cassi, Xavier; Timoneda, Natàlia; Carratalà, Anna; Abril, Josep Francesc; Silvera, Carolina; Figueras, Maria José; Gelati, Emiliano; Rodó, Xavier; Kay, David; Wyn-Jones, Peter; Bofill-Mas, Sílvia; Girones, Rosina

    2015-08-15

    Conventional wastewater treatment does not completely remove and/or inactive viruses; consequently, viruses excreted by the population can be detected in the environment. This study was undertaken to investigate the distribution and seasonality of human viruses and faecal indicator bacteria (FIB) in a river catchment located in a typical Mediterranean climate region and to discuss future trends in relation to climate change. Sample matrices included river water, untreated and treated wastewater from a wastewater treatment plant within the catchment area, and seawater from potentially impacted bathing water. Five viruses were analysed in the study. Human adenovirus (HAdV) and JC polyomavirus (JCPyV) were analysed as indicators of human faecal contamination of human pathogens; both were reported in urban wastewater (mean values of 10(6) and 10(5) GC/L, respectively), river water (10(3) and 10(2) GC/L) and seawater (10(2) and 10(1) GC/L). Human Merkel Cell polyomavirus (MCPyV), which is associated with Merkel Cell carcinoma, was detected in 75% of the raw wastewater samples (31/37) and quantified by a newly developed quantitative polymerase chain reaction (qPCR) assay with mean concentrations of 10(4) GC/L. This virus is related to skin cancer in susceptible individuals and was found in 29% and 18% of river water and seawater samples, respectively. Seasonality was only observed for norovirus genogroup II (NoV GGII), which was more abundant in cold months with levels up to 10(4) GC/L in river water. Human hepatitis E virus (HEV) was detected in 13.5% of the wastewater samples when analysed by nested PCR (nPCR). Secondary biological treatment (i.e., activated sludge) and tertiary sewage disinfection including chlorination, flocculation and UV radiation removed between 2.22 and 4.52 log10 of the viral concentrations. Climate projections for the Mediterranean climate areas and the selected river catchment estimate general warming and changes in precipitation distribution

  20. Evidence of viral dissemination and seasonality in a Mediterranean river catchment: Implications for water pollution management.

    Science.gov (United States)

    Rusiñol, Marta; Fernandez-Cassi, Xavier; Timoneda, Natàlia; Carratalà, Anna; Abril, Josep Francesc; Silvera, Carolina; Figueras, Maria José; Gelati, Emiliano; Rodó, Xavier; Kay, David; Wyn-Jones, Peter; Bofill-Mas, Sílvia; Girones, Rosina

    2015-08-15

    Conventional wastewater treatment does not completely remove and/or inactive viruses; consequently, viruses excreted by the population can be detected in the environment. This study was undertaken to investigate the distribution and seasonality of human viruses and faecal indicator bacteria (FIB) in a river catchment located in a typical Mediterranean climate region and to discuss future trends in relation to climate change. Sample matrices included river water, untreated and treated wastewater from a wastewater treatment plant within the catchment area, and seawater from potentially impacted bathing water. Five viruses were analysed in the study. Human adenovirus (HAdV) and JC polyomavirus (JCPyV) were analysed as indicators of human faecal contamination of human pathogens; both were reported in urban wastewater (mean values of 10(6) and 10(5) GC/L, respectively), river water (10(3) and 10(2) GC/L) and seawater (10(2) and 10(1) GC/L). Human Merkel Cell polyomavirus (MCPyV), which is associated with Merkel Cell carcinoma, was detected in 75% of the raw wastewater samples (31/37) and quantified by a newly developed quantitative polymerase chain reaction (qPCR) assay with mean concentrations of 10(4) GC/L. This virus is related to skin cancer in susceptible individuals and was found in 29% and 18% of river water and seawater samples, respectively. Seasonality was only observed for norovirus genogroup II (NoV GGII), which was more abundant in cold months with levels up to 10(4) GC/L in river water. Human hepatitis E virus (HEV) was detected in 13.5% of the wastewater samples when analysed by nested PCR (nPCR). Secondary biological treatment (i.e., activated sludge) and tertiary sewage disinfection including chlorination, flocculation and UV radiation removed between 2.22 and 4.52 log10 of the viral concentrations. Climate projections for the Mediterranean climate areas and the selected river catchment estimate general warming and changes in precipitation distribution

  1. 2013 Annual Summary Report for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada National Security Site, Nye County, Nevada; Review of the Performance Assessments and Composite Analyses

    Energy Technology Data Exchange (ETDEWEB)

    Shott, Gregory [NSTec

    2014-03-01

    The Maintenance Plan for the Performance Assessments and Composite Analyses for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site (National Security Technologies, LLC 2007a) requires an annual review to assess the adequacy of the performance assessments (PAs) and composite analyses (CAs), with the results submitted to the U.S. Department of Energy (DOE) Office of Environmental Management. The Disposal Authorization Statements for the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) also require that such reviews be made and that secondary or minor unresolved issues be tracked and addressed as part of the maintenance plan (DOE 1999a, 2000). The U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office performed an annual review of the Area 3 and Area 5 RWMS PAs and CAs for fiscal year (FY) 2013. This annual summary report presents data and conclusions from the FY 2013 review, and determines the adequacy of the PAs and CAs. Operational factors (e.g., waste forms and containers, facility design, and waste receipts), closure plans, monitoring results, and research and development (R&D) activities were reviewed to determine the adequacy of the PAs. Likewise, the environmental restoration activities at the Nevada National Security Site (NNSS) relevant to the sources of residual radioactive material that are considered in the CAs, the land-use planning, and the results of the environmental monitoring and R&D activities were reviewed to determine the adequacy of the CAs. Important developments in FY 2013 include the following: • Development of a new Area 5 RWMS closure inventory estimate based on disposals through FY 2013 • Evaluation of new or revised waste streams by special analysis • Development of version 4.115 of the Area 5 RWMS GoldSim PA/CA model The Area 3 RWMS has been in inactive status since July 1, 2006, with the last shipment received in April 2006. The FY 2013 review of operations

  2. Process-based modelling of a headwater catchment in semi-arid conditions: the influence of macropore flow

    NARCIS (Netherlands)

    Schaik, N.L.M.B.; Bronstert, A.; Jong, S.M.; Jetten, V.G.; Dam, van J.C.; Ritsema, C.J.; Schnabel, S.

    2014-01-01

    Subsurface stormflow is thought to occur mainly in humid environments with steep terrains. However, in semi-arid areas, preferential flow through macropores can also result in a significant contribution of subsurface stormflow to catchment runoff for varying catchment conditions. Most hydrological m

  3. Biogeographic areas and transition zones of Latin America and the Caribbean islands based on panbiogeographic and cladistic analyses of the entomofauna.

    Science.gov (United States)

    Morrone, Juan J

    2006-01-01

    Track and cladistic biogeographic analyses based on insect taxa are used as a framework to interpret patterns of the Latin American and Caribbean entomofauna by identifying biogeographic areas on the basis of endemicity and arranging them hierarchically in a system of regions, subregions, dominions, and provinces. The Nearctic region, inhabited by Holarctic insect taxa, comprises five provinces: California, Baja California, Sonora, Mexican Plateau, and Tamaulipas. The Mexican transition zone comprises five provinces: Sierra Madre Occidental, Sierra Madre Oriental, Transmexican Volcanic Belt, Balsas Basin, and Sierra Madre del Sur. The Neotropical region, which harbors many insect taxa with close relatives in the tropical areas of the Old World, comprises four subregions: Caribbean, Amazonian, Chacoan, and Parana. The South American transition zone comprises five provinces: North Andean Paramo, Coastal Peruvian Desert, Puna, Atacama, Prepuna, and Monte. The Andean region, which harbors insect taxa with close relatives in the Austral continents, comprises three subregions: Central Chilean, Subantarctic, and Patagonian.

  4. Linkwater catchment groundwater residence time, flow pattern, and hydrochemistry trends

    International Nuclear Information System (INIS)

    Water demand in the Marlborough Sounds Linkwater catchment is increasing due to pasture irrigation by dairy farmers. Little is known about the geology and the hydrology of the area. Resource management decisions are being made without a sound understanding of sustainable limits. Groundwater is the main potential source for irrigation water at Linkwater. Marlborough District Council requires a baseline hydrological assessment of the flow characteristics of the Linkwater catchment to guide day-to-day allocation practice and advice to Council. While this may be regarded as a baseline study, according to Marlborough District Council consent records, a significant amount of water (around 10,000 m3/day) has already been allocated at Linkwater. It is assumed that Linkwater catchment water is derived predominantly from local rainfall, either directly onto the flats or as surface run-off from the adjacent ranges via Cullens Creek and other smaller creeks. The variation in well depth at Linkwater suggests that there are different water-bearing formations, ranging from shallow flow through the alluvial gravels recharged by seepage from Cullens Creek or recent rainfall, to medium and deep aquifers that may contain older water. The objective of this study is to establish the hydrogeology of the Linkwater area, and groundwater flow patterns from the isotopic and chemical signature of the water, including the sources of catchment recharge and mean residence times of the water in the catchment. Tritium, chloroflurocarbons (CFCs) and sulphur hexafluoride (SF6) are used for age dating, and δ18O, N2, Ar, CH4 and a full chemical assessment at all sites (including arsenic, nutrients and heavy metals) are used along with the age data to identify flow characteristics. (author). 26 refs., 18 figs., 5 tabs

  5. Modelling the effects of land use changes on the streamflow of a peri-urban catchment in central Portugal

    Science.gov (United States)

    Hävermark, Saga; Santos Ferreira, Carla Sofia; Kalantari, Zahra; Di Baldassarre, Giuliano

    2016-04-01

    was calibrated for the hydrological years 2008 to 2010 and validated for the three following years using streamflow data. The impact of future land use changes was analysed by investigating the impact of the size and location of the urban areas within the catchment. Modelling results are expected to support the decision making process in planning and developing new urban areas.

  6. 2008 Annual Summary Report for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site, Nye County, Nevada: Review of the Performance Assessments and Composite Analyses

    Energy Technology Data Exchange (ETDEWEB)

    NSTec Environmental Management

    2009-03-30

    The Maintenance Plan for the Performance Assessments and Composite Analyses for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site requires an annual review to assess the adequacy of the Performance Assessments (PAs) and Composite Analyses (CAs) for each of the facilities, with the results submitted annually to U.S. Department of Energy (DOE) Headquarters. The Disposal Authorization Statements for the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) also require that such reviews be made and that secondary or minor unresolved issues be tracked and addressed as part of the maintenance plan. The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO) performed an annual review in fiscal year (FY) 2008 by evaluating operational factors and research results that impact the continuing validity of the PAs and CAs. This annual summary report presents data and conclusions from the FY 2008 review, and determines the adequacy of the PAs and CAs. Operational factors (e.g., waste forms and containers, facility design, and waste receipts), closure plans, monitoring results, and research and development (R&D) activities were reviewed to determine the adequacy of the PAs. Likewise, the environmental restoration activities at the Nevada Test Site relevant to the sources of residual radioactive material that are considered in the CAs, the land-use planning, and the results of the environmental monitoring and R&D activities were reviewed to determine the adequacy of the CAs.

  7. Waste dumps rehabilitation measures based on physico-chemical analyses in Zăghid mining area (Sălaj County, Romania

    Directory of Open Access Journals (Sweden)

    Ildiko M. Varga

    2011-08-01

    Full Text Available The present study deals with an abandoned coal mine from Zăghid area, North-WesternTransylvanian Basin (Sălaj County. The mining activity was stopped in 2005, without any attempt ofecological rehabilitation of the mined area and especially of the waste dumps left behind. The proposedrehabilitation models are based on some physical-chemical analyses of soil and waste samples (e.g. pH,EC, Salinity, humidity, porosity, density, plasticity, organic substances, mineralogical composition, heavymetals. Erosion map has been drawn based on the determined mineralogical composition (accordingSTAS 1913/5-85 – using Galton curve of tailings and the soil type. The values obtained for moisture andplasticity have been used to determine the ideal general inclination angle of the landfill systems in thestudied perimeter. Through chemical analysis, heavy metals like Ni and Cu have been identified, as themain pollution factors for surface and underground water. Therefore, the concentration of heavy metalsin the waters from Zăghid area is high in the water bodies, which are formed on waste dumps, but alsoin the mine water. This analysis is useful in establishing the actual state of the waste dumps and theircontent and the negative effects, which exercise on the environment in order to select the rehabilitationmodel for the waste dumps from Zăghid mining area. The main measures consist in: waste dumpsleveling, soil remediation, perennial plants culture and acid mine water decontamination.

  8. Longterm Measurements of Bedload-Transport in alpine Catchments

    Science.gov (United States)

    Achleitner, Stefan; Kammerlander, Johannes; Eichner, Bernhard; Schöber, Johannes; Chiari, Michael

    2016-04-01

    the long-term bed load budget of small mountain creeks. First analyses are presented to link catchment descriptors to transport efficiencies. Both, between-sites and within-site (temporal) variability of transport efficiency is determined.

  9. Using object-based geomorphometry for hydro-geomorphological analysis in a Mediterranean research catchment

    Science.gov (United States)

    Guida, Domenico; Cuomo, Albina; Palmieri, Vincenzo

    2016-08-01

    The aim of the paper is to apply an object-based geomorphometric procedure to define the runoff contribution areas and support a hydro-geomorphological analysis of a 3 km2 Mediterranean research catchment (southern Italy). Daily and sub-hourly discharge and electrical conductivity data were collected and recorded during a 3-year monitoring activity. Hydro-chemograph analyses carried out on these data revealed a strong seasonal hydrological response in the catchment that differed from the stormflow events that occur in the wet periods and in dry periods. This analysis enabled us to define the hydro-chemograph signatures related to increasing flood magnitude, which progressively involves various runoff components (baseflow, subsurface flow and surficial flow) and an increasing contributing area to discharge. Field surveys and water table/discharge measurements carried out during a selected storm event enabled us to identify and map specific runoff source areas with homogeneous geomorphological units previously defined as hydro-geomorphotypes (spring points, diffuse seepage along the main channel, seepage along the riparian corridors, diffuse outflow from hillslope taluses and concentrate sapping from colluvial hollows). Following the procedures previously proposed and used by authors for object-based geomorphological mapping, a hydro-geomorphologically oriented segmentation and classification was performed with the eCognition (Trimble, Inc.) package. The best agreement with the expert-based geomorphological mapping was obtained with weighted plan curvature at different-sized windows. By combining the hydro-chemical analysis and object-based hydro-geomorphotype map, the variability of the contribution areas was graphically modeled for the selected event, which occurred during the wet season, by using the log values of flow accumulation that better fit the contribution areas. The results allow us to identify the runoff component on hydro-chemographs for each time step

  10. Effect of the spatial distribution of physical aquifer properties on modelled water table depth and stream discharge in a headwater catchment

    Directory of Open Access Journals (Sweden)

    C. Gascuel-Odoux

    2010-07-01

    Full Text Available Water table depth and its dynamics on hillslopes are often poorly predicted despite they control both water transit time within the catchment and solute fluxes at the catchment outlet. This paper analyses how relaxing the assumption of lateral homogeneity of physical properties can improve simulations of water table depth and dynamics. Four different spatial models relating hydraulic conductivity to topography have been tested: a simple linear relationship, a linear relationship with two different topographic indexes, two Ks domains with a transitional area. The Hill-Vi model has been modified to test these hypotheses. The studied catchment (Kervidy-Naizin, Western France is underlain by schist crystalline bedrock. A shallow and perennial groundwater highly reactive to rainfall events mainly develops in the weathered saprolite layer. The results indicate that (1 discharge and the water table in the riparian zone are similarly predicted by the four models, (2 distinguishing two Ks domains constitutes the best model and slightly improves prediction of the water table upslope, and (3 including spatial variations in the other parameters such as porosity or rate of hydraulic conductivity decrease with depth does not improve the results. These results underline the necessity of better investigations of upslope areas in hillslope hydrology.

  11. The effects of land use and its patterns on soil properties in a small catchment of the Loess Plateau

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Due to relatively strong human activities in the hilly area of Loess Plateau, the natural vegetation has been destroyed, and landscapepattern based on agricultural land matrix was land use mosaic composing of shrub land, grassland, woodland and orchard.This pattern has animportant effect on soil moisture and soil nutrients.The Danangou catchment, a typical small catchment, was selected to study the effects ofland use and its patterns on soil moisture and nutrients in this paper.The results are as follows: The comparisons of soil moisture among sevenland uses for wet year and dry year were performed: (1) the average of soil moisture content for whole catchment was 12.11% in wet year,while it was 9.37% in dry year; (2) soil moisture among seven land uses was significantly different in dry year, but not in wet year; (3) fromwet year to dry year, the profile type of soil moisture changed from decreasing type to fluctuation-type and from fluctuant type to increasingtype; (4) the increasing trend in soil moisture from the top to foot of hillslope occurred in simple land use along slope, while complicateddistribution of soil moisture was observed in multiple land uses along slope.The relationships between soil nutrients and land uses and landscapepositions were analysed: ( 1 ) five nutrient contents of soil organic matter (SOM), total N (TN), available N (AN), total P (TP) andavailable P (AP) in hilly area were lower than that in other areas.SOM content was less than 1%, TN content less than 0.07%, and TPcontent between 0.05% and 0.06%; (2) SOM and TN contents in woodland, shrub land and grassland were significantly higher than that infallow land and cropland, and higher level in soil fertility was found in crop-fruit intercropping land among croplands; (3) soil nutrientdistribution and responses to landscape positions were variable depending on slope and the location of land use types.

  12. The 87Sr/86Sr aquatic isoscape of the Danube catchment from the source to the mouth as tool for studying fish migrations

    Science.gov (United States)

    Zitek, Andreas; Tchaikovsky, Anastassiya; Irrgeher, Johanna; Waidbacher, Herwig; Prohaska, Thomas

    2014-05-01

    Isoscapes - spatially distributed isotope patterns across landscapes - are increasingly used as important basis for ecological studies. The natural variation of the isotopic abundances in a studied area bears the potential to be used as natural tracer for studying e.g. migrations of animals or prey-predator relations. The 87Sr/86Sr ratio is one important tracer, since it is known to provide a direct relation of biological samples to geologically distinct regions, as Sr isotopes are incorporated into living tissues as a proxy for calcium and taken up from the environment without any significant fractionation. Although until now the focus has been mainly set on terrestrial systems, maps for aquatic systems are increasingly being established. Here we present the first 87Sr/86Sr aquatic isoscape of the Danube catchment, the second largest river catchment in Europe, from near its source starting at river km 2581 in Germany down to its mouth to river km 107 in Romania. The total length of the river Danube is 2780 km draining a catchment area 801 463 km2 (10 % of the European continent). The major purpose of this study was to assess the potential of the 87Sr/86Sr isotope ratio to be used as tool for studying fish migrations at different scales in the entire Danube catchment. Within the Joint Danube Research 3 (JDS 3), the biggest scientific multi-disciplinary river expedition of the World in 2013 aiming at the assessment of the ecological status and degree of human alterations along the river Danube, water samples were taken at 68 pre-defined sites along the course of the river Danube including the major tributaries as a basis to create the so called 'Isoscape of the Danube catchment'. The determination of 87Sr/86Sr isotope ratio in river water was performed by multicollector-sector field-inductively coupled plasma-mass spectrometry (MC-SF-ICP-MS). The JDS 3 data were combined with existing data from prior studies conducted within the Austrian part of the Danube catchment

  13. Quantifying the hydrological impact of simulated changes in land use on peak discharge in a small catchment.

    Science.gov (United States)

    Kalantari, Zahra; Lyon, Steve W; Folkeson, Lennart; French, Helen K; Stolte, Jannes; Jansson, Per-Erik; Sassner, Mona

    2014-01-01

    A physically-based, distributed hydrological model (MIKE SHE) was used to quantify overland runoff in response to four extreme rain events and four types of simulated land use measure in a catchment in Norway. The current land use in the catchment comprises arable lands, forest, urban areas and a stream that passes under a motorway at the catchment outlet. This model simulation study demonstrates how the composition and configuration of land use measures affect discharge at the catchment outlet differently in response to storms of different sizes. For example, clear-cutting on 30% of the catchment area produced a 60% increase in peak discharge and a 10% increase in total runoff resulting from a 50-year storm event in summer, but the effects on peak discharge were less pronounced during smaller storms. Reforestation of 60% of the catchment area was the most effective measure in reducing peak flows for smaller (2-, 5- and 10-year) storms. Introducing grassed waterways reduced water velocity in the stream and resulted in a 28% reduction in peak flow at the catchment outlet for the 50-year storm event. Overall, the results indicate that the specific effect of land use measures on catchment discharge depends on their spatial distribution and on the size and timing of storm events. PMID:23973540

  14. Modeling of matters removal from swampy catchment

    Science.gov (United States)

    Inishev, N. G.; Inisheva, L. I.

    2010-05-01

    This work shows the results of fixed study of geochemical conditions in the system of landscape oligotrophic profile at Vasyugan mire spurs, and also we make an approach to processes modelling of compounds removal from swampy catchment. During investigation of symbolic model of chemical matters removal from the surface of a catchment basin and their movement along the channel network it was taken into account that removal of chemical elements during the period of spring flood and rain high waters occur mainly with overland flow. During calculation of dissolved matters movement the following admissions take place: 1. The problem is solved at one-dimension set-up. Concentration of investigated components is taken as averaged one along the flow cross section or effective area of slope cross-section for overland runoff, i.e. it changes only lengthways and in time. 2. It is considered that dissolved matters spread due to movement of water and together with its particles. 3. Processes of water self-clarification are not considered. The model is calculated on the basis of discharge of the investigated ingredient, i.e. matter mass moving through the given flow cross-section into time unit. This is the peculiarity of the model. Matter removal together with water flow is determined if necessary. Everyday impurity consumptions and its concentration can be estimated at the outlet at the moment of time according to convolution integral. Estimation of overland runoff and water inflow into the channel network is based on the mathematic model of outflow formation from peatland areas which considers basic processes carrying out at catchment and basin channel network. Stored moisture estimation of snow cover is taken according to snow survey data before snow melting. Everyday water supply to the surface of water collection was determined according to the results of snow melt intensity estimation by the methods of temperature coefficient and water yield from snow (A.G. Kovzel). All

  15. Spatiotemporal Hydrological Modelling with GIS for the Upper Mahaweli Catchment, Sri Lanka

    OpenAIRE

    Premalal de Silva, Ranjith

    1997-01-01

    Sustainability of water resources is imperative for the continued prosperity of Sri Lanka where the economy is dependent upon agriculture. The Mahaweli river is the longest in Sri Lanka, with the upper catchment covering an area of 3124 sq .km .. The Mahaweli Development programme, a major undertaking in the upper catchment has been implemented with the aims of providing Mahaweli water to the dry zone of the country through a massive diversion scheme and also for generating hyd...

  16. 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.

  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. A bottom up approach for engineering catchments through sustainable runoff management

    Science.gov (United States)

    Wilkinson, M.; Quinn, P. F.; Jonczyk, J.; Burke, S.

    2010-12-01

    There is no doubt that our catchments are under great stress. There have been many accounts around the world of severe flood events and water quality issues within channels. As a result of these, ecological habitats in rivers are also under pressure. Within the United Kingdom, all these issues have been identified as key target areas for policy. Traditionally this has been managed by a policy driven top down approach which is usually ineffective. A one ‘size fits all’ attitude often does not work. This paper presents a case study in northern England whereby a bottom up approach is applied to multipurpose managing of catchments at the source (in the order of 1-10km2). This includes simultaneous tackling of water quality, flooding and ecological issues by creating sustainable runoff management solutions such as storage ponds, wetlands, beaver dams and willow riparian features. In order to identify the prevailing issues in a specific catchment, full and transparent stakeholder engagement is essential, with everybody who has a vested interest in the catchment being involved from the beginning. These problems can then be dealt with through the use of a novel catchment management toolkit, which is transferable to similar scale catchments. However, evidence collected on the ground also allows for upscaling of the toolkit. The process gathers the scientific evidence about the effectiveness of existing or new measures, which can really change the catchment functions. Still, we need to get better at communicating the science to policy makers and policy therefore must facilitate a bottom up approach to land and water management. We show a test site for this approach in the Belford burn catchment (6km2), northern England. This catchment has problems with flooding and water quality. Increased sediment loads are affecting the nearby estuary which is an important ecological zone and numerous floods have affected the local village. A catchment engineering toolkit has been

  19. Estimation of erosion and sediment export from an agricultural catchment

    OpenAIRE

    Evrard, Olivier; Nord, Guillaume; Cerdan, Olivier; Souchère, Véronique; Le Bissonnais, Yves; Bonté, Philippe

    2010-01-01

    Soil erosion leads to important environmental problems (e.g. muddy floods, reservoir sedimentation) in cultivated areas of the European loess belt. This study aimed to quantify erosion and to determine the impact of rainfall seasonality and land use change on soil erosion over the last 40 years in a 94-ha cultivated catchment of Normandy (France). To this end, scenarios representative of the different land use conditions were simulated using the STREAM expert-based erosion model. A 13-yrs lon...

  20. Lowland forest butterflies of the Sankosh River catchment, Bhutan

    OpenAIRE

    Singh, A. P.

    2012-01-01

    This paper provides information on butterflies of the lowland forests of Bhutan for the first time. As a part of the biodiversity impact assessment for the proposed Sankosh hydroelectric power project, a survey was carried out along the Sankosh River catchment to study the butterfly diversity. The aim of the study was to identify species of conservation priority, their seasonality and to know the butterfly diversity potential of the area. Surveys were carried out during five different seas...

  1. Parsimonious hydrological modeling of urban sewer and river catchments

    OpenAIRE

    Coutu, Sylvain; Del Giudice, Dario; Rossi, Luca; Barry, David Andrew

    2012-01-01

    A 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 th...

  2. The status of persistent organic pollutants in Lake Victoria catchment

    OpenAIRE

    Madadi, O.V; Wandiga, S.O.; Jumba, I.O.

    2006-01-01

    The use of most organochlorine pesticides has been banned or restricted in the republic of Kenya under the Rotterdam and Stockholm convention due to high levels of persistence in the environment and toxicity to nontarget organisms. Studies conducted in some parts of the country have revealed that residue levels of these compounds are still in the environment. However, the residues of these compounds have not been exhaustively studied in the Lake Victoria catchment area. This study was set to ...

  3. The Lune catchment abstraction management strategy. Consultation document September 2003

    OpenAIRE

    2003-01-01

    This consultation document sets out the proposed future licensing strategy for the Lune Catchment Abstraction Management Strategy (CAMS) area. Following the three month consultation period, the Environment Agency will determine the final licensing strategy and publish it in the CAMS document. The strategy will provide an indication of whether new abstraction licences are likely to be available and the conditions that should be expected on licences. Water plays a vi...

  4. Constructed wetlands to reduce metal pollution from industrial catchments in aquatic Mediterranean ecosystems: a review to overcome obstacles and suggest potential solutions.

    Science.gov (United States)

    Guittonny-Philippe, Anna; Masotti, Véronique; Höhener, Patrick; Boudenne, Jean-Luc; Viglione, Julien; Laffont-Schwob, Isabelle

    2014-03-01

    In the Mediterranean area, surface waters often have low discharge or renewal rates, hence metal contamination from industrialised catchments can have a high negative impact on the physico-chemical and biological water quality. In a context of climate and anthropological changes, it is necessary to provide an integrative approach for the prevention and control of metal pollution, in order to limit its impact on water resources, biodiversity, trophic network and human health. For this purpose, introduction of constructed wetlands (CWs) between natural aquatic ecosystems and industrialised zones or catchments is a promising strategy for eco-remediation. Analysis of the literature has shown that further research must be done to improve CW design, selection and management of wetland plant species and catchment organisation, in order to ensure the effectiveness of CWs in Mediterranean environments. Firstly, the parameters of basin design that have the greatest influence on metal removal processes must be identified, in order to better focus rhizospheric processes on specific purification objectives. We have summarised in a single diagram the relationships between the design parameters of a CW basin and the physico-chemical and biological processes of metal removal, on the basis of 21 mutually consistent papers. Secondly, in order to optimise the selection and distribution of helophytes in CWs, it is necessary to identify criteria of choice for the plant species that will best fit the remediation objectives and environmental and economic constraints. We have analysed the factors determining plant metal uptake efficiency in CWs on the basis of a qualitative meta-analysis of 13 studies with a view to determine whether the part played by metal uptake by plants is relevant in comparison with the other removal processes. Thirdly, we analysed the parameters to consider for establishing suitable management strategies for CWs and how they affect the whole CW design process

  5. 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.

  6. Seasonal exports of phosphorus from intensively fertilised nested grassland catchments

    Institute of Scientific and Technical Information of China (English)

    Ciaran Lewis; Rashad Rafique; Nelius Foley; Paul Leahy; Gerard Morgan; John Albertson; Sandeep Kumar

    2013-01-01

    We carried out a one year (2002) study of phosphorus (P) loss from soil to water in three nested grassland catchments with known P input in chemical fertilizer and animal liquid slurry applications.Chemical fertilizer was applied to the grasslands between March and September and animal slurry was applied over the twelve months.The annual chemical P fertilizer applications for the 17 and 211 ha catchments were 16.4 and 23.7 kg P/ha respectively and the annual slurry applications were 10.7 and 14.0 kg P/ha,respectively.The annual total phosphorus (TP) export in stream-flow was 2.61,2.48 and 1.61 kg P/ha for the 17,211 and 1524 ha catchments,respectively,compared with a maximum permissible (by regulation) annual export of ca.0.35 kg P/ha.The export rate (ratio of P export to P in land applications) was 9.6% and 6.6% from the 17 and 211 ha catchments,respectively.On average,70% of stream flow and 85% of the P export occurred during the five wet months (October to February) indicating that when precipitation is much greater than evaporation,the hydrological conditions are most favourable for P export.However the soil quality and land use history may vary the results.Particulate P made up 22%,43% and 37% of the TP export at the 17,211 and 1524 ha catchment areas,respectively.As the chemical fertilizer was spread during the grass growth months (March to September),it has less immediate impact on stream water quality than the slurry applications.We also show that as the catchment scale increases,the P concentrations and P export decrease,confirming dilution due to increasing rural catchment size.In the longer term,the excess P from fertilizer maintains high soil P levels,an antecedent condition favourable to P loss from soil to water.This study confirms the significant negative water quality impact of excess P applications,particularly liquid animal slurry applications in wet winter months.The findings suggest that restricted P application in wet months can

  7. Evaluation of catchment delineation methods for the medium-resolution National Hydrography Dataset

    Science.gov (United States)

    Johnston, Craig M.; Dewald, Thomas G.; Bondelid, Timothy R.; Worstell, Bruce B.; McKay, Lucinda D.; Rea, Alan; Moore, Richard B.; Goodall, Jonathan L.

    2009-01-01

    Different methods for determining catchments (incremental drainage areas) for stream segments of the medium-resolution (1:100,000-scale) National Hydrography Dataset (NHD) were evaluated by the U.S. Geological Survey (USGS), in cooperation with the U.S. Environmental Protection Agency (USEPA). The NHD is a comprehensive set of digital spatial data that contains information about surface-water features (such as lakes, ponds, streams, and rivers) of the United States. The need for NHD catchments was driven primarily by the goal to estimate NHD streamflow and velocity to support water-quality modeling. The application of catchments for this purpose also demonstrates the broader value of NHD catchments for supporting landscape characterization and analysis. Five catchment delineation methods were evaluated. Four of the methods use topographic information for the delineation of the NHD catchments. These methods include the Raster Seeding Method; two variants of a method first used in a USGS New England study-one used the Watershed Boundary Dataset (WBD) and the other did not-termed the 'New England Methods'; and the Outlet Matching Method. For these topographically based methods, the elevation data source was the 30-meter (m) resolution National Elevation Dataset (NED), as this was the highest resolution available for the conterminous United States and Hawaii. The fifth method evaluated, the Thiessen Polygon Method, uses distance to the nearest NHD stream segments to determine catchment boundaries. Catchments were generated using each method for NHD stream segments within six hydrologically and geographically distinct Subbasins to evaluate the applicability of the method across the United States. The five methods were evaluated by comparing the resulting catchments with the boundaries and the computed area measurements available from several verification datasets that were developed independently using manual methods. The results of the evaluation indicated that the two

  8. The applicability of an 87Sr/86Sr river isoscape to fish ecological questions in the Danube catchment

    Science.gov (United States)

    Zitek, A.; Irrgeher, J.; Sailer, K.; Trautwein, C.; Waidbacher, H.; Prohaska, T.

    2012-04-01

    Isoscapes are spatial maps of the distribution of isotopes on Earth. As a basis for ecological studies such as long distance migrations of animals or for determining the origin of food these tools are increasingly being developed, until now - mainly for terrestrial systems. In contrast, in case of aquatic systems only few maps were established up to now. As far as variation in the isotopic distribution in a studied area exists, the isotopic composition bears the potential to be used as natural tracer e.g. for ecological questions or food authentication. Above all the 87Sr/86Sr ratio taken up from the environment by organisms without any significant fractionation is known to provide a direct link to geologically distinct regions. Within the 'IsoMark' project (www.isomark.at), a database ('Isoscape Austria') containing all available spatially explicit isotope data (terrestrial and aquatic) with a focus on isotope distributions in Austrian rivers is being developed. Water samples from different rivers, mainly along the Danube in Austria, were collected and analyzed for their elemental and Sr isotopic composition. Analyses of water samples yielded several 'Isozones' along the Austrian part of the Danube, indicating diverse geology in these river catchments. Studying migration phenomena of fish using natural isotopic marks in hard parts is especially possible between these 'Isozones'. In geologically similar regions with little differences, element distributions or artificial marking methods (tagging, spiking) can serve as additional means. A significant positive relationship between the 87Sr/86Sr ratio in river water and the proportion of siliceous geological formations in the catchment was found on a national and European level. These analyses proved the possibility to predict the 87Sr/86Sr ratios in river catchments all over Europe. This relationship allows for an estimation of the applicability of the 87Sr/86Sr ratio for fish ecological questions on a European scale

  9. Localisation of nursery areas based on comparative analyses of the horizontal and vertical distribution patterns of juvenile Baltic cod (Gadus morhua)

    DEFF Research Database (Denmark)

    Nielsen, J. Rasmus; Lundgren, Bo; Kristensen, Kasper;

    2013-01-01

    Knowledge of the spatial distribution of juvenile cod is essential for obtaining precise recruitment data to conduct sustainable management of the eastern and western Baltic cod stocks. In this study, the horizontal and vertical distribution and density patterns of settled juvenile 0- and 1-group...... and acoustic research surveys. Horizontal distribution maps for the 2001–2010 cohorts of juvenile cod are further generated by applying a statistical log-Gaussian Cox process model to the standard trawl survey data. The analyses indicate size-dependent horizontal and distinct vertical and diurnal distribution...... patterns related to the seabed topography, water layer depth, and the presence of hydrographic frontal zones (pycnoclines) as well as intraspecific patterns in relation to the presence of adult cod. The extent of the nursery areas also depends on the cod year class strength. Juvenile cod (≥3 cm...

  10. Nitrous oxide and methane exchange in two small temperate forest catchments - effects of hydrological gradients and implications for global warming potentials of forest soils

    DEFF Research Database (Denmark)

    Christiansen, Jesper Riis; Vesterdal, Lars; Gundersen, Per

    2012-01-01

    half the catchment area at both sites, the global warming potential (GWP) derived from N2O and CH4 was more than doubled when accounting for these wet areas in the catchments. The results stress the importance of wet soils in assessments of forest soil global warming potentials, as even small...

  11. Groundwater–surface water interactions, vegetation dependencies and implications for water resources management in the semi-arid Hailiutu River catchment, China – a synthesis

    Directory of Open Access Journals (Sweden)

    Y. Zhou

    2013-07-01

    Full Text Available During the last decades, large-scale land use changes took place in the Hailiutu River catchment, a semi-arid area in northwest China. These changes had significant impacts on the water resources in the area. Insights into groundwater and surface water interactions and vegetation-water dependencies help to understand these impacts and formulate sustainable water resources management policies. In this study, groundwater and surface water interactions were identified using the baseflow index at the catchment scale, and hydraulic and water temperature methods as well as event hydrograph separation techniques at the sub-catchment scale. The results show that almost 90% of the river discharge consists of groundwater. Vegetation dependencies on groundwater were analysed from the relationship between the Normalized Difference Vegetation Index (NDVI and groundwater depth at the catchment scale and along an ecohydrogeological cross-section, and by measuring the sap flow of different plants, soil water contents and groundwater levels at different research sites. The results show that all vegetation types, i.e. trees (willow (Salix matsudana and poplar (Populus simonii, bushes (salix – Salix psammophila, and agricultural crops (maize – Zea mays, depend largely on groundwater as the source for transpiration. The comparative analysis indicates that maize crops use the largest amount of water, followed by poplar trees, salix bushes, and willow trees. For sustainable water use with the objective of satisfying the water demand for socio-economical development and to prevent desertification and ecological impacts on streams, more water-use-efficient crops such as sorghum, barley or millet should be promoted to reduce the consumptive water use. Willow trees should be used as wind-breaks in croplands and along roads, and drought-resistant and less water-use intensive plants (for instance native bushes should be used to vegetate sand dunes.

  12. 2011 Annual Summary Report for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada National Security Site, Nye County, Nevada: Review of the Performance Assessments and Composite Analyses

    Energy Technology Data Exchange (ETDEWEB)

    NSTec Environmental Management

    2012-03-20

    The Maintenance Plan for the Performance Assessments and Composite Analyses for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site (National Security Technologies, LLC, 2007a) requires an annual review to assess the adequacy of the Performance Assessments (PAs) and Composite Analyses (CAs), with the results submitted annually to U.S. Department of Energy (DOE) Office of Environmental Management. The Disposal Authorization Statements for the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) also require that such reviews be made and that secondary or minor unresolved issues be tracked and addressed as part of the maintenance plan (DOE, 1999a; 2000). The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office performed an annual review of the Area 3 and Area 5 RWMS PAs and CAs for fiscal year (FY) 2011. This annual summary report presents data and conclusions from the FY 2011 review, and determines the adequacy of the PAs and CAs. Operational factors (e.g., waste forms and containers, facility design, and waste receipts), closure plans, monitoring results, and research and development (R and D) activities were reviewed to determine the adequacy of the PAs. Likewise, the environmental restoration activities at the Nevada National Security Site (NNSS) (formerly the Nevada Test Site) relevant to the sources of residual radioactive material that are considered in the CAs, the land-use planning, and the results of the environmental monitoring and R and D activities were reviewed to determine the adequacy of the CAs. Important developments in FY 2011 include the following: (1) Operation of a new shallow land disposal unit and a new Resource Conservation and Recovery Act (RCRA)-compliant lined disposal unit at the Area 5 RWMS; (2) Development of new closure inventory estimates based on disposals through FY 2011; (3) Evaluation of new or revised waste streams by special analysis; (4) Development of

  13. Predictions of rainfall-runoff response and soil moisture dynamics in a microscale catchment using the CREW model

    Directory of Open Access Journals (Sweden)

    H. Lee

    2006-07-01

    scale pressure-saturation (i.e., water retention curve and hydraulic conductivity-saturation relationships for the unsaturated zone. Closure relations for concentrated overland flow and saturated overland flow were derived using both theoretical arguments and simpler process models. In addition to these, to complete the specification of the REW scale balance equations, a relationship for the saturated area fraction as a function of saturated zone depth was derived for an assumed topography on the basis of TOPMODEL assumptions. These relationships were used to complete the specification of all of the REW-scale governing equations (mass and momentum balance equations, closure and geometric relations for the Weiherbach catchment, which are then employed for constructing a numerical watershed model, named the Cooperative Community Catchment model based on the Representative Elementary Watershed approach (CREW. CREW is then used to carry out sensitivity analyses with respect to various combinations of climate, soil, vegetation and topographies, in order to test the reasonableness of the derived closure relations in the context of the complete catchment response, including interacting processes. These sensitivity analyses demonstrated that the adopted closure relations do indeed produce mostly reasonable results, and can therefore be a good basis for more careful and rigorous search for appropriate closure relations in the future. Three tests are designed to assess CREW as a large scale model for Weiherbach catchment. The first test compares CREW with distributed model CATFLOW by looking at predicted soil moisture dynamics for artificially designed initial and boundary conditions. The second test is designed to see the applicabilities of the parameter values extracted from the upscaling procedures in terms of their ability to reproduce observed hydrographs within the CREW modeling framework. The final test compares simulated soil

  14. Predicting temporal development of discharge and nitrate in relation to dynamic changes of spatial crop distribution in three land use scenario runs with a catchment model

    Science.gov (United States)

    Guse, Björn; Pfannerstill, Matthias; Geertz, Jörn; Fohrer, Nicola

    2014-05-01

    In the past years, relevant changes in the use of agricultural areas were observed in German catchments. To achieve good ecological conditions in river basins as demanded by the European Water Framework Directive, the implications of land use change on water quantity and especially water quality needs to be quantified. Therefore, recent data of agricultural crops are prepared for the catchment scale. Based on this, simulations of future land use scenarios are carried out with a hydrological catchment model to analyse the linkage between dynamic changes of land use and modeled discharge and nutrients. Spatial and temporal variations of changes within agricultural areas lead to a dynamic change of pressures on the ecological status of rivers. While static land use distributions assume constant conditions for agricultural areas for the whole simulation period, dynamic changes of agricultural areas and their spatial patterns consider the varying land use conditions within the scenario simulation. In our study, a dynamic modeling of spatial distributions for agricultural crops and its impacts on discharge and nitrate is presented at the catchment scale. The area proportions of the crops are estimated in a data-based statistical approach and are implemented into the eco-hydrological model SWAT for recent and future conditions To obtain an accurate reproduction of the water cycle, the SWAT model is calibrated for discharge and nitrate time series for recent conditions. Three land use change scenarios are developed for the study catchment focusing on a dominance of food production, energy crops and on a best ecological practise. According to the scenarios, the spatial crop distribution is updated dynamically for each year, while non-agricultural land use types remain constant. The SWAT model provides satisfying results for discharge and nitrate. The evaluation of the three land use change scenarios for the period from 2021 to 2030 shows low differences in discharge, while

  15. 2012 Annual Summary Report for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada National Security Site, Nye County, Nevada: Review of the Performance Assessments and Composite Analyses

    Energy Technology Data Exchange (ETDEWEB)

    Shott, G. [National Security Technologies, LLC

    2013-03-18

    The Maintenance Plan for the Performance Assessments and Composite Analyses for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site (National Security Technologies, LLC 2007a) requires an annual review to assess the adequacy of the performance assessments (PAs) and composite analyses (CAs), with the results submitted to the U.S. Department of Energy (DOE) Office of Environmental Management. The Disposal Authorization Statements for the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) also require that such reviews be made and that secondary or minor unresolved issues be tracked and addressed as part of the maintenance plan (DOE 1999a, 2000). The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office performed an annual review of the Area 3 and Area 5 RWMS PAs and CAs for fiscal year (FY) 2012. This annual summary report presents data and conclusions from the FY 2012 review, and determines the adequacy of the PAs and CAs. Operational factors (e.g., waste forms and containers, facility design, and waste receipts), closure plans, monitoring results, and research and development (R&D) activities were reviewed to determine the adequacy of the PAs. Likewise, the environmental restoration activities at the Nevada National Security Site (NNSS) relevant to the sources of residual radioactive material that are considered in the CAs, the land-use planning, and the results of the environmental monitoring and R&D activities were reviewed to determine the adequacy of the CAs. Important developments in FY 2012 include the following: Release of a special analysis for the Area 3 RWMS assessing the continuing validity of the PA and CA; Development of a new Area 5 RWMS closure inventory estimate based on disposals through FY 2012; Evaluation of new or revised waste streams by special analysis; and Development of version 4.114 of the Area 5 RWMS GoldSim PA model. The Area 3 RWMS has been in inactive status since

  16. Identifying Catchment-Scale Predictors of Coal Mining Impacts on New Zealand Stream Communities

    Science.gov (United States)

    Clapcott, Joanne E.; Goodwin, Eric O.; Harding, Jon S.

    2016-03-01

    Coal mining activities can have severe and long-term impacts on freshwater ecosystems. At the individual stream scale, these impacts have been well studied; however, few attempts have been made to determine the predictors of mine impacts at a regional scale. We investigated whether catchment-scale measures of mining impacts could be used to predict biological responses. We collated data from multiple studies and analyzed algae, benthic invertebrate, and fish community data from 186 stream sites, including un-mined streams, and those associated with 620 mines on the West Coast of the South Island, New Zealand. Algal, invertebrate, and fish richness responded to mine impacts and were significantly higher in un-mined compared to mine-impacted streams. Changes in community composition toward more acid- and metal-tolerant species were evident for algae and invertebrates, whereas changes in fish communities were significant and driven by a loss of nonmigratory native species. Consistent catchment-scale predictors of mining activities affecting biota included the time post mining (years), mining density (the number of mines upstream per catchment area), and mining intensity (tons of coal production per catchment area). Mining was associated with a decline in stream biodiversity irrespective of catchment size, and recovery was not evident until at least 30 years after mining activities have ceased. These catchment-scale predictors can provide managers and regulators with practical metrics to focus on management and remediation decisions.

  17. Soil weathering rates in 21 catchments of the Canadian Shield

    Directory of Open Access Journals (Sweden)

    D. Houle

    2012-03-01

    Full Text Available Soil mineral weathering represents an essential source of nutrient base cation (Ca, Mg and K for forest growth in addition to provide a buffering power against precipitation acidity for soils and surface waters. Weathering rates of base cations were obtained for 21 catchments located within the temperate and the boreal forest of the Canadian Shield with the geochemical model PROFILE. Weathering rates ranged from 0.58 to 4.46 kmolc ha−1 yr−1 and their spatial variation within the studied area was mostly in agreement with spatial variations in soil mineralogy. Weathering rates of Ca and Mg were significantly correlated (r = 0.80 and 0.64 with their respective lake concentrations. Weathering rates of K and Na did not correlate with lake concentrations of K and Na. The modeled weathering rates for each catchment were also compared with estimations of net catchment exportations. The result show that modeled weathering rates of Ca were not significantly different than the net catchment exportations while modeled weathering rates of Mg were higher by 51%. Larger differences were observed for K and Na weathering rates that were significantly different than net catchment exportations being 6.9 and 2.2 times higher than net exportations, respectively. The results for K were expected given its high reactivity with biotic compartments and suggest that most of the K produced by weathering reactions was retained within soil catchments and/or above ground biomass. This explanation does not apply to Na, however, which is a conservative element in forest ecosystems because of the insignificant needs of Na for soil microorganisms and above ground vegetations. It raises concern about the liability of the PROFILE model to provide reliable values of Na weathering rates. Overall, we concluded that the PROFILE model is powerful enough to reproduce spatial geographical gradients in weathering rates for relatively large areas

  18. Sediment budget for Rediu reservoir catchment, North-Eastern Romania

    Science.gov (United States)

    Todosi, Cristian; Niculita, Mihai

    2016-04-01

    Sediment budgets are a useful tool for geomorphologic analysis, catchment management and environmental assessment, despite the uncertainties related to their assessment. We present the sediment budget construction and validation for a small catchment of 9.5319 kmp (953.19 ha) situated in the North-Eastern part of Romania. The Rediu reservoir was built between 1986 and 1988, on Rediu valley, a left tributary of Bahlui river, north-west from Iasi city. The catchment of the reservoir has 6.5 km in length and 2.5 km in maximum width, the altitudes decreasing from 170 m in the northern part, to 52 m in the southern part. The valley is symmetric, the altitude of the hillslopes going between 200 m to 75 m in one km length, in the transversal section with the maximum width. The floodplain is narrow having between 20 m to 210 m (in the area of confluence with Breazu tributary). The mean slope of the catchment is 6.4 degree, the maximum slope being 24.6 degrees. The length of channels which show banks of up to 2 m is 19.98 km. The land is used predominantly as crops (58.1 %), 16.7 % being covered by pastures (from which over half are eroded), 11.5 % percent of the catchment being covered by planted forests, 9.2 % by rural constructions and roads, 2.9 % by hayfields, 1.5 % by lakes and 0.1 % by orchards. Beside the Rediu reservoir, there are three ponds (15 771, 1761 and 751 sqm) in the catchment. We considered the trap efficiency for the reservoir and the ponds to be 95%. Aerial images from 1963, 1978 , 1984, 2005, 2008, 2010, 2012 and 2014 were used to assess the state of geomorphological processes before and after the reservoir construction. After 1970 a gully system situated in Breazu tributary sub-catchment and several active landslides along the main valley left side were forested. Beside these processes, soil erosion and human impact by constructions are the main processes generating sediment in the study area. The sediment yields were quantified by estimating the

  19. Modeling nonlinear responses of DOC transport in boreal catchments in Sweden

    Science.gov (United States)

    Kasurinen, Ville; Alfredsen, Knut; Ojala, Anne; Pumpanen, Jukka; Weyhenmeyer, Gesa A.; Futter, Martyn N.; Laudon, Hjalmar; Berninger, Frank

    2016-07-01

    Stream water dissolved organic carbon (DOC) concentrations display high spatial and temporal variation in boreal catchments. Understanding and predicting these patterns is a challenge with great implications for water quality projections and carbon balance estimates. Although several biogeochemical models have been used to estimate stream water DOC dynamics, model biases common during both rain and snow melt-driven events. The parsimonious DOC-model, K-DOC, with 10 calibrated parameters, uses a nonlinear discharge and catchment water storage relationship including soil temperature dependencies of DOC release and consumption. K-DOC was used to estimate the stream water DOC concentrations over 5 years for eighteen nested boreal catchments having total area of 68 km2 (varying from 0.04 to 67.9 km2). The model successfully simulated DOC concentrations during base flow conditions, as well as, hydrological events in catchments dominated by organic and mineral soils reaching NSEs from 0.46 to 0.76. Our semimechanistic model was parsimonious enough to have all parameters estimated using statistical methods. We did not find any clear differences between forest and mire-dominated catchments that could be explained by soil type or tree species composition. However, parameters controlling slow release and consumption of DOC from soil water behaved differently for small headwater catchments (less than 2 km2) than for those that integrate larger areas of different ecosystem types (10-68 km2). Our results emphasize that it is important to account for nonlinear dependencies of both, soil temperature, and catchment water storage, when simulating DOC dynamics of boreal catchments.

  20. Influence of aquifer heterogeneity on karst hydraulics and catchment delineation employing distributive modeling approaches

    Directory of Open Access Journals (Sweden)

    S. Oehlmann

    2013-07-01

    Full Text Available Due to their heterogeneous nature, karst aquifers pose a major challenge for hydrogeological investigations. Important procedures like the delineation of catchment areas for springs are hindered by the unknown locations and hydraulic properties of highly conductive karstic zones. In this work numerical modeling was employed as a tool in delineating catchment areas of several springs within a karst area in southwestern Germany. For this purpose, different distributive modeling approaches were implemented in the Finite Element simulation software Comsol Multiphysics®. The investigation focuses on the question to which degree the effect of karstification has to be taken into account for accurately simulating the hydraulic head distribution and the observed spring discharges. The results reveal that the representation of heterogeneities has a large influence on the delineation of the catchment areas. Not only the location of highly conductive elements but also their geometries play a major role for the resulting hydraulic head distribution and thus for catchment area delineation. The size distribution of the karst conduits derived from the numerical models agrees with knowledge from karst genesis. It was thus shown that numerical modeling is a useful tool for catchment delineation in karst aquifers based on results from different field observations.

  1. The Civitavecchia Coastal Environment Monitoring System (C-CEMS: a new tool to analyse the conflicts between coastal pressures and sensitivity areas

    Directory of Open Access Journals (Sweden)

    S. Bonamano

    2015-07-01

    Full Text Available The understanding of the coastal environment is fundamental for efficiently and effectively facing the pollution phenomena, as expected by Marine Strategy Directive, which is focused on the achievement of Good Environmental Status (GES by all Member States by 2020. To address this, the Laboratory of Experimental Oceanology and Marine Ecology developed a multi-platform observing network that has been in operation since 2005 in the coastal marine area of Civitavecchia, where multiple uses and high ecological values closely coexist. The Civitavecchia Coastal Environment Monitoring System (C-CEMS, implemented in the current configuration, includes various modules that provide integrated information to be used in different fields of the environmental research. The long term observations acquired by the fixed stations are integrated by in situ surveys, periodically carried out for the monitoring of the physical, chemical and biological characteristics of the water column and marine sediments, as well as of the benthic biota. The in situ data, integrated with satellite observations (e.g., temperature, chlorophyll a and TSM, are used to feed and validate the numerical models, which allow analyses and forecasting of the dynamics of conservative and non-conservative particles under different conditions. As examples of C-CEMS applications, two case studies are reported in this work: (1 the analysis of faecal bacteria dispersion for bathing water quality assessment and, (2 the evaluation of the effects of the dredged activities on Posidonia meadows, which make up most of the two sites of community importance located along the Civitavecchia coastal zone. The simulations results are combined with Posidonia oceanica distribution and bathing areas presence in order to resolve the conflicts between coastal uses (in terms of stress produced by anthropic activities and sensitivity areas management.

  2. 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.

  3. Monitoring and modeling the snowpack dynamics in the Arve upper catchment for hydrological purposes

    Science.gov (United States)

    Revuelto, Jesús; Lecourt, Grégoire; Charrois, Luc; Lafaysse, Matthieu; Condom, Thomas; Dumont, Marie; Morin, Samuel; Rabatel, Antoine; Six, Delphine; Vionnet, Vincent; Zin, Isabella

    2016-04-01

    Snow accumulation and its evolution over space and time have major importance for the hydrological cycle, especially at high elevations. The characteristics of mountain valley, such as a wide altitudinal range, large glaciated areas, snow presence all along the year; when combined with specific meteorological conditions like heat waves or extreme rain events, may originate dramatic flash floods, potentially affecting populated areas. Thus, improving snowpack monitoring and forecasting tools are needed to strength the reliability of warning systems. Nowadays, accurately characterising and simulating snowpack evolution over large areas still represents a challenge, and uncertainties arise. The study presented here is focused in analysing two different types of simulation of the snowpack dynamics, performed with different discretization approaches, distributed or semi-distributed, and how these could move forward assimilating remote sensing data from satellites. The considered study area is the Arve catchment at Chamonix, in the French Northern Alps. This valley has the previously mentioned characteristics: it comprises a large elevation range (between 1000 to 4800m asl, with large areas above 2000m asl) and about 32% of its extension (200km2) is glaciated. Thus, the hydrological cycle of this area is highly dependent on the snowpack and the glacier melt dynamics. The snowpack of the Arve catchment has been simulated from 1990 to 2014 with the Crocus model integrated within the SURFEX modelling platform. The input fields are provided by the SAFRAN reanalysis system and the simulations have been performed with both a semi-distributed (classifying terrain by aspect, elevation, slope and land use/land cover) and a distributed (250m spatial resolution grid cells over the study area) approaches. The use of these two approaches using the same snowpack model and same meteorological forcing, enables their comparison in terms of river discharges at several outlets; showing the

  4. Hydro-Meteorological Drought Projections into the 21-st Century for Selected Polish Catchments

    Directory of Open Access Journals (Sweden)

    Hadush K. Meresa

    2016-05-01

    Full Text Available The nature of drought conditions is estimated using a range of indices describing different aspects of drought events. Three drought indices are evaluated, namely the Standardized Precipitation Index (SPI, Standardized Precipitation Evapotranspiration Index (SPEI and Standardized Runoff Index (SRI, using observed hydroclimatic data and applying them to hydro-meteorological projections into the 21st century. The first two indices are evaluated using only meteorological variables and from this point of view, are better suited to meteorological drought projections than the third index, SRI, which is based on catchment discharge and represents hydrological drought. We assess information contained in those indices and their suitability to catchment scale climate projection drought assessment in ten selected Polish catchments, representing different hydro-climatic conditions, which are used as a case study. Projections of climatic variables (precipitation and temperature are obtained from the EURO-CORDEX initiative derived from seven climate models at a grid resolution of 12.5 km for the time period 1971–2100. Future runoff projections for the catchments are obtained using a conceptual rainfall-runoff model (HBV. The results of analyses of indices based on observations in the reference period show consistent estimates for most of the catchments. Hydro-meteorological climate model projections for three periods, including the reference period 1971–2000, and two 30-year periods, near-future 2021–2050 and far-future 2071–2100, are used to estimate changes of future drought conditions in the catchments studied. The results show a substantial variation of temporal drought patterns over the catchments and their dependence on projected precipitation and temperature variables and the type of indices applied. Of the three indices studied, only SPEI projections indicate drier conditions in the catchments in the far-future period. The other two indices

  5. SEASONAL CHANGES IN PHOSPHORUS LOAD FLOWING OUT OF SMALL AGRICULTURAL CATCHMENTS

    Directory of Open Access Journals (Sweden)

    Krzysztof Pulikowski

    2014-12-01

    Full Text Available In this article distribution of monthly phosphorus loads flowing out of two agricultural catchments which are located in different physiographic conditions of Lower Silesia was analysed. Loads of phosphorus runoff from the catchment located in the piedmont part of Lower Silesia in each month rarely exceed 0.10 kg P ∙ ha-1. The size of annual load is determined by loads obtained in two months of early spring. Much lower loads obtained for lowland catchment, located near Wroclaw. Values ​​calculated for each month rarely exceed the value of 0.01 kg P ∙ ha-1. Culmination of loads bringing away is a bit more extended in a time compared to the catchment located on Sudety Mts. Foreland. Much higher loads are observed during the period from January to April – this period has a major impact on the size of phosphorus load that flows out from this catchment during whole hydrological year. The obtained results clearly indicate that the threat of watercourses and water reservoirs supply in phosphorus compounds from agricultural land is periodic and it is particularly high during early spring. Phosphorus load flowing out from the analyzed catchments is very diverse. From facility located on Sudety Foothill in hydrological year, during research period, flowed away average 0.81 kg P ∙ ha-1. Significantly lower values were obtained for second facility and it was average 0.15 kg P ∙ ha-1 during a year. The size of load discharged during a year is largely determined by amount of phosphorus load flowing out during winter half of the year (from XI to IV. In case of foothill catchment in this period flowed out average 0.56 kg P ∙ ha-1, which presents 69% of annual load and in lowland catchment this percentage was even slightly higher and was 73%.

  6. Streamflow response of a small forested catchment on different time scales

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    A. Zabaleta

    2012-08-01

    Full Text Available The hydrological response of a catchment to rainfall on different time scales is result of a complex system involving a range of physical processes which may operate simultaneously and have different spatial and temporal influences. This paper presents the analysis of streamflow response of a small humid-temperate catchment (Aixola, 4.8 km2 in the Basque Country on different time scales and discusses the role of the controlling factors. Firstly, daily time series analysis was used to establish a hypothesis on the general functioning of the catchment through the relationship between precipitation and discharge on an annual and multi-annual scale (2003–2008. Second, rainfall-runoff relationships and relationships among several hydrological variables, including catchment antecedent conditions, were explored at the event scale (222 events to check and improve the hypothesis. Finally, the evolution of electrical conductivity (EC during some of the monitored storm events (28 events was examined to identify the time-origin of waters. Quick response of the catchment to almost all the rainfall events as well as a considerable regulation capacity was deduced from the correlation and spectral analyses. These results agree with runoff event scale data analysis; however the event analysis revealed the non-linearity of the system, as antecedent conditions play a significant role in this catchment. Further, analysis at the event scale made possible to clarify factors controlling (precipitation, precipitation intensity and initial discharge the different aspects of the runoff response (runoff coefficient and discharge increase for this catchment. Finally, the evolution of EC of the waters enabled the time origin (event or pre-event waters of the quickflow to be established; specifically, the conductivity showed that pre-event waters usually represent a high percentage of the total discharge during runoff peaks. The importance of soil waters in the

  7. Climate and terrain factors explaining streamflow response and recession in Australian catchments

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    A. I. J. M. van Dijk

    2010-01-01

    Full Text Available Daily streamflow data were analysed to assess which climate and terrain factors best explain streamflow response in 183 Australian catchments. Assessed descriptors of catchment response included the parameters of fitted baseflow models, and baseflow index (BFI, average quick flow and average baseflow derived by baseflow separation. The variation in response between catchments was compared with indicators of catchment climate, morphology, geology, soils and land use. Spatial coherence in the residual unexplained variation was investigated using semi-variogram techniques. A linear reservoir model (one parameter; recession coefficient produced baseflow estimates as good as those obtained using a non-linear reservoir (two parameters and for practical purposes was therefore considered an appropriate balance between simplicity and explanatory performance. About a third (27–34% of the spatial variation in recession coefficients and BFI was explained by catchment climate indicators, with another 53% of variation being spatially correlated over distances of 100–150 km, probably indicative of substrate characteristics not captured by the available soil and geology data. The shortest recession half-times occurred in the driest catchments and were attributed to intermittent occurrence of fast-draining (possibly perched groundwater. Most (70–84% of the variation in average baseflow and quick flow was explained by rainfall and climate characteristics; another 20% of variation was spatially correlated over distances of 300–700 km, possibly reflecting a combination of terrain and climate factors. It is concluded that catchment streamflow response can be predicted quite well on the basis of catchment climate alone. The prediction of baseflow recession response should be improved further if relevant substrate properties were identified and measured.

  8. Climate and hydrological variability: the catchment filtering role

    Science.gov (United States)

    Andrés-Doménech, I.; García-Bartual, R.; Montanari, A.; Marco, J. B.

    2015-01-01

    Measuring the impact of climate change on flood frequency is a complex and controversial task. Identifying hydrological changes is difficult given the factors, other than climate variability, which lead to significant variations in runoff series. The catchment filtering role is often overlooked and thus may hinder the correct identification of climate variability signatures on hydrological processes. Does climate variability necessarily imply hydrological variability? This research aims to analytically derive the flood frequency distribution based on realistic hypotheses about the rainfall process and the rainfall-runoff transformation. The annual maximum peak flow probability distribution is analytically derived to quantify the filtering effect of the rainfall-runoff process on climate change. A sensitivity analysis is performed according to typical semi-arid Mediterranean climatic and hydrological conditions, assuming a simple but common scheme for the rainfall-runoff transformation in small-size ungauged catchments, i.e. the CN-SCS model. Variability in annual maximum peak flows and its statistical significance are analysed when changes in the climatic input are introduced. Results show that depending on changes in the annual number of rainfall events, the catchment filtering role is particularly significant, especially when the event rainfall volume distribution is not strongly skewed. Results largely depend on the return period: for large return periods, peak flow variability is significantly affected by the climatic input, while for lower return periods, infiltration processes smooth out the impact of climate change.

  9. Climate and hydrological variability: the catchment filtering role

    Directory of Open Access Journals (Sweden)

    I. Andrés-Doménech

    2014-09-01

    Full Text Available Measuring the impact of climate change on flood frequency is a complex and controversial task. Identifying hydrological changes is difficult given the factors, other than climate variability, which lead to significant variations in runoff series. The catchment filtering role is often overlooked and in fact, this may hinder the correct identification of climate variability signatures on hydrological processes. Does climate variability necessarily imply hydrological variability? The research herein presented aims to analytically derive the flood frequency distribution basing on realistic hypotheses about the rainfall process and the rainfall–runoff transformation. The peak flow probability distribution is analytically derived to quantify the filtering effect operated by the rainfall–runoff process on climate change. A sensitivity analysis is performed according to typical semi-arid Mediterranean climatic and hydrological conditions, assuming a simple but common scheme for the rainfall–runoff transformation in small-size ungauged catchments, i.e. the CN-SCS model. Variability in peak flows and its statistical significance are analysed when changes in the climatic input are introduced. Results show that in regard to changes in the annual number of rainfall events, the catchment filtering role is particularly significant when the event rainfall volume distribution is not strongly skewed. Results largely depend on the return period: for large return periods, peak flow variability is significantly impacted by the climatic input, while for lower return periods, infiltration processes smooth out the effects of climate change.

  10. 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...

  11. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: NLCD 2001 Land Use and Land Cover

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set represents the estimated area of land use and land cover from the National Land Cover Dataset 2001 (LaMotte, 2008), compiled for every catchment of...

  12. Attributes for NHDPlus Catchments (Version 1.1) in the Conterminous United States: Artificial Drainage (1992) and Irrigation Types (1997)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular dataset represents the estimated area of artificial drainage for the year 1992 and irrigation types for the year 1997 compiled for every catchment of...

  13. 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,...

  14. Diagramas de Voronoi para a definição de áreas de abrangência de hospitais públicos no Município do Rio de Janeiro Defining catchment areas for public hospitals in the Municipality of Rio de Janeiro through Weighted Voronoi Diagrams

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    Flavio Astolpho Vieira Souto Rezende

    2000-06-01

    Full Text Available No planejamento de recursos em saúde é importante o conhecimento da área de abrangência de uma unidade. Os Diagramas de Voronoi constituem uma técnica para tal; são polígonos construídos de tal forma que as bordas de polígonos adjacentes encontram-se eqüidistantes de seus respectivos pontos geradores. Uma modificação nas áreas de abrangência assim definidas é sua ponderação (Diagramas de Voronoi ponderados, representando a capacidade da unidade de forma mais real. No presente trabalho foram utilizados, como pontos geradores, 21 hospitais gerais públicos no Rio de Janeiro, RJ. Inicialmente foram criados os Diagramas de Voronoi sem ponderação, e, a partir destes, os diagramas ponderados, empregando-se como variável de ponderação as estimativas de internação anual para cada unidade. Na divisão clássica, áreas de abrangência similares foram atribuídas a hospitais com características diferenciadas, problema esse contornado no método ponderado. O método é de simples implementação e visualização, utiliza dados de fácil acesso e independe de parâmetros arbitrários ou geopolíticos. Portanto, esses diagramas podem fornecer, a gerentes de saúde, uma visão mais realista para o planejamento da demanda de suas unidades.One of the most important pieces of information for health resources planning is the definition of catchment areas for health units. Voronoi Diagrams are a potential technique for this purpose. They are polygons with the property whereby adjacent polygons have their borders located within the same distance of the respective generator points. One possible adjustment to the catchment areas thus defined is the use of weighted Voronoi Diagrams, which result in an improved representation of a health unit's actual capacity. In this study, the 21 public general hospitals in the city of Rio de Janeiro, Brazil, were used as generator points for Voronoi Diagrams. Non-weighted Voronoi Diagrams were initially

  15. 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

  16. Modelling the initial structure dynamics of soil and sediment exemplified for a constructed hydrological catchment

    Science.gov (United States)

    Maurer, Thomas; Schneider, Anna; Gerke, Horst H.

    2014-05-01

    Knowledge about spatial heterogeneity is of essential for the analysis of the hydrological catchment behavior. Heterogeneity is directly related to the distribution of the solid phase, and in initial hydrological systems, the solid phase is mainly composed of mineral particles. In artificial catchments, such sediment structures relate to the applied construction technology. It is supposed that the development of catchment ecosystems is strongly influenced by such specific initial spatial distributions of the solid phase. Moreover, during the initial development period, the primary structures in a catchment are altered rapidly by translocation processes, thereby subdividing the initial system in different compartments. Questions are: How does initial sediment distribution affect further structural development? How is catchment hydrology influenced by the initial structural development? What structures have a relevant impact on catchment-scale hydrological behavior? We present results from a structural modelling approach using a process-based structure generator program. The constructed hydrological catchment 'Hühnerwasser' (Lower Lusatia, Brandenburg, Germany) served exemplarily for the model development. A set of scenarios was created describing possible initial heterogeneities of the catchment. Both the outcrop site from where the parent material was excavated and the specific excavation procedures were considered in the modelling approach. Generated distributions are incorporated in a gridded 3D volume model constructed with the GOCAD software. Results were evaluated by semivariogram analysis and by quantifying point-to-point deviations. We also introduce a modelling conception for simulating the highly dynamic initial structural change, based on the generated initial distributions. We present a strategy on how to develop the initial structure generator into an integrative tool in order to (i) simulate and analyse the spatio-temporal development dynamics

  17. Catchments as space-time filters – a joint spatio-temporal geostatistical analysis of runoff and precipitation

    Directory of Open Access Journals (Sweden)

    J. O. Skøien

    2006-06-01

    Full Text Available In this paper catchments are conceptualised as linear space-time filters. Catchment area A is interpreted as the spatial support and the catchment response time Tis interpreted as the temporal support of the runoff measurements. These two supports are related by T~Aκ which embodies the space-time connections of the rainfall-runoff process from a geostatistical perspective. To test the framework, spatio-temporal variograms are estimated from about 30 years of quarter hourly precipitation and runoff data from about 500 catchments in Austria. In a first step, spatio-temporal variogram models are fitted to the sample variograms for three catchment size classes independently. In a second step, variograms are fitted to all three catchment size classes jointly by estimating the parameters of a point/instantaneous spatio-temporal variogram model and aggregating (regularising it to the spatial and temporal scales of the catchments. The exponential, Cressie-Huang and product-sum variogram models give good fits to the sample variograms of runoff with dimensionless errors ranging from 0.02 to 0.03, and the model parameters are plausible. This indicates that the first order effects of the spatio-temporal variability of runoff are indeed captured by conceptualising catchments as linear space-time filters. The scaling exponent κ is found to vary between 0.3 and 0.4 for different variogram models.

  18. Catchments as space-time filters – a joint spatio-temporal geostatistical analysis of runoff and precipitation

    Directory of Open Access Journals (Sweden)

    J. O. Skøien

    2006-01-01

    Full Text Available In this paper catchments are conceptualised as linear space-time filters. Catchment area A is interpreted as the spatial support and the catchment response time T is interpreted as the temporal support of the runoff measurements. These two supports are related by T~Aκ which embodies the space-time connections of the rainfall-runoff process from a geostatistical perspective. To test the framework, spatio-temporal variograms are estimated from about 30 years of quarter hourly precipitation and runoff data from about 500 catchments in Austria. In a first step, spatio-temporal variogram models are fitted to the sample variograms for three catchment size classes independently. In a second step, variograms are fitted to all three catchment size classes jointly by estimating the parameters of a point/instantaneous spatio-temporal variogram model and aggregating (regularising it to the spatial and temporal scales of the catchments. The exponential, Cressie-Huang and product-sum variogram models give good fits to the sample variograms of runoff with dimensionless errors ranging from 0.02 to 0.03, and the model parameters are plausible. This indicates that the first order effects of the spatio-temporal variability of runoff are indeed captured by conceptualising catchments as linear space-time filters. The scaling exponent κ is found to vary between 0.3 and 0.4 for different variogram models.

  19. Chances and pitfalls of leaf wax biomarker analyses applied to fluvial sediment sequences - the example of a Holocene fluvial sediment-paleosol sequence from the upper Alazani River, eastern Georgia

    Science.gov (United States)

    von Suchodoletz, Hans; Bliedtner, Marcel; Zielhofer, Christoph; Faust, Dominik; Zech, Roland

    2016-04-01

    During the last decades, fluvial sediment sequences in many regions have intensively been studied to reconstruct Late Quaternary palaeoenvironmental and palaeohydrological conditions. However, up to now analyses of leaf wax biomarkers that are increasingly used to reconstruct paleoenvironmental and -climate conditions e.g. from lake sediments or loess-paleosol sequences were not systematically applied to Late Quaternary fluvial sediments. Given the ubiquitous distribution of fluvial sediment sequences on the earth's surface such investigations could potentially strongly enhance the knowledge about former environmental conditions in many regions. For this conceptual study we exemplarily analysed leaf wax biomarker (long-chain n-alkanes, n-alkanoic acids) in a fluvial sediment palaeosol sequence from the upper Alazani River in eastern Georgia to discuss general possibilities and pitfalls: Generally, biomarker records from fluvial archives can be divided into i) a catchment signal recorded in the fluvial sediment layers and ii) a local in-situ signal recorded in the intercalated paleosols. This offers the great chance to reconstruct paleoenvironmental conditions in both the whole catchment and at the sampling site. However, potential pitfalls are, for example, that inherited catchment signals can bias the in-situ signal from paleosols, while intermediate sediment storage in the catchment prior to sediment deposition and postsedimentary processes may alter the original catchment signal in the fluvial sediment layers. Thus, when applying leaf wax biomarker analyses to fluvial sediment sequences one has to be careful: The interpretation of the biomarker record strongly depends on the specific geomorphological and sedimentological conditions of the investigated site and of the catchment area.

  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. Hydrologic connectivity between landscapes and streams: Transferring reach- and plot-scale understanding to the catchment scale

    Science.gov (United States)

    Jencso, K.G.; McGlynn, B.L.; Gooseff, M.N.; Wondzell, S.M.; Bencala, K.E.; Marshall, L.A.

    2009-01-01

    The relationship between catchment structure and runoff characteristics is poorly understood. In steep headwater catchments with shallow soils the accumulation of hillslope area (upslope accumulated area (UAA)) is a hypothesized first-order control on the distribution of soil water and groundwater. Hillslope-riparian water table connectivity represents the linkage between the dominant catchment landscape elements (hillslopes and riparian zones) and the channel network. Hydrologic connectivity between hillslope-riparian-stream (HRS) landscape elements is heterogeneous in space and often temporally transient. We sought to test the relationship between UAA and the existence and longevity of HRS shallow groundwater connectivity. We quantified water table connectivity based on 84 recording wells distributed across 24 HRS transects within the Tenderfoot Creek Experimental Forest (U.S. Forest Service), northern Rocky Mountains, Montana. Correlations were observed between the longevity of HRS water table connectivity and the size of each transect's UAA (r2 = 0.91). We applied this relationship to the entire stream network to quantify landscape-scale connectivity through time and ascertain its relationship to catchment-scale runoff dynamics. We found that the shape of the estimated annual landscape connectivity duration curve was highly related to the catchment flow duration curve (r2 = 0.95). This research suggests internal catchment landscape structure (topography and topology) as a first-order control on runoff source area and whole catchment response characteristics. Copyright 2009 by the American Geophysical Union.

  2. Safeguarding the provision of ecosystem services in catchment systems.

    Science.gov (United States)

    Everard, Mark

    2013-04-01

    A narrow technocentric focus on a few favored ecosystem services (generally provisioning services) has led to ecosystem degradation globally, including catchment systems and their capacities to support human well-being. Increasing recognition of the multiple benefits provided by ecosystems is slowly being translated into policy and some areas of practice, although there remains a significant shortfall in the incorporation of a systemic perspective into operation management and decision-making tools. Nevertheless, a range of ecosystem-based solutions to issues as diverse as flooding and green space provision in the urban environment offers hope for improving habitat and optimization of beneficial services. The value of catchment ecosystem processes and their associated services is also being increasingly recognized and internalized by the water industry, improving water quality and quantity through catchment land management rather than at greater expense in the treatment costs of contaminated water abstracted lower in catchments. Parallel recognition of the value of working with natural processes, rather than "defending" built assets when catchment hydrology is adversely affected by unsympathetic upstream development, is being progressively incorporated into flood risk management policy. This focus on wider catchment processes also yields a range of cobenefits for fishery, wildlife, amenity, flood risk, and other interests, which may be optimized if multiple stakeholders and their diverse value systems are included in decision-making processes. Ecosystem services, particularly implemented as a central element of the ecosystem approach, provide an integrated framework for building in these different perspectives and values, many of them formerly excluded, into commercial and resource management decision-making processes, thereby making tractable the integrative aspirations of sustainable development. This can help redress deeply entrenched inherited assumptions

  3. 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).

  4. Hydrological monitoring of experimental karst catchment Sutina - Karakašica

    Science.gov (United States)

    Bonacci, O.; Andrić, I.

    2012-04-01

    The Sutina - Karakašica is an ungauged karst catchment in southern part of Croatia with relative small area but with existing records of several events of flash flood that compromised the structures as bridge and roads along the stream. This poster gives an overview of the creation of the experimental catchment and establishment of the hydrological monitoring system which has for a goal a better understanding of runoff processes within the experimental karst area as well as flash flood occurrence analysis. The studied catchment is located in Dalmatia, southern part of Croatia, a region of Dinaric karst. Although it is very difficult to determine catchment borders in the karstic terrain, for the porpoises of the study the area of the catchment is estimated to 8 km2. The length of the stream flow up to the control cross section is 4.4 km. The highest point of the studied catchment area is on the 941 m a.s.l. and the lowest at the 300 m a.s.l. The geological settings of the catchment are characterized by the sedimentary rocks, mostly limestone and dolomites with discontinuities (cracks, and fractures) filled up with terra rossa and breccias. The presence of mudstone patches in the surface ensures the continuous surface flow of the studied stream. Some caves are also to be found in the catchment area. In the karst watersheds the occurrence of flash floods can be registered due to the exceptional meteorologic events during the year. The intensive rainfall in the short time period can trigger a flash flood that can induce overbank flow, immense changes in channel morphology and in sediment distribution. In order to produce a hydrological model that could predict the events of flash flood in the studied area, a continuous monitoring of meteorological and hydrological parameters in the catchment is established. The predictions of exceptional flooding events derived from a useful hydrological model based on the study site can be used further on to quantify the possible

  5. 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.

  6. The impact of forest regeneration on streamflow in 12 meso-scale humid tropical catchments

    Directory of Open Access Journals (Sweden)

    H. E. Beck

    2013-03-01

    Full Text Available Although regenerating forests make up an increasingly large portion of humid tropical landscapes, comparatively little is known of their water use and effects on streamflow (Q. Since the 1950s the island of Puerto Rico has experienced widespread abandonment of pastures and agricultural lands, followed by forest regeneration. This paper examines the possible impacts of forest regeneration on several Q metrics for 12 meso-scale catchments (23–346 km2; mean precipitation 1720–3422 mm yr−1 with long (33–51 yr and simultaneous records for Q, precipitation (P, potential evapotranspiration (PET, and land cover. A simple spatially-lumped, conceptual rainfall-runoff model that uses daily P and PET time series as inputs (HBV-light was used to simulate Q for each catchment. Annual time series of observed and simulated values of four Q metrics were calculated. A least-squares trend was fitted through annual time series of the residual difference between observed and simulated time series of each Q metric. From this the total cumulative change  was calculated, representing the change in each metric after controlling for climate variability and water storage carry-over effects between years. Negative values of  were found for most catchments and Q metrics, suggesting enhanced actual evapotranspiration overall following forest regeneration. However, correlations between changes in urban or forest area and values of  were insignificant (p ≥ 0.389 for all Q metrics. This suggests there is no convincing evidence that changes in the chosen Q metrics in these Puerto Rican catchments can be ascribed to changes in urban or forest area. The present results are in line with previous studies of meso- and macro-scale (sub-tropical catchments, which generally found no significant change in Q that can be attributed to changes in forest cover. Possible explanations for the apparent lack of a clear signal may include: errors in the land-cover, climate, Q

  7. Effects of catchment and riparian landscape setting on water chemistry and seasonal evolution of water quality in the upper Han River basin, China.

    Directory of Open Access Journals (Sweden)

    Siyue Li

    Full Text Available Six-year (2005-2010 evolution of water chemistry (Cl(-, NO(3(-, SO(4(2-, HCO(3(-, Na(+, K(+, Ca(2+ and Mg(2+ and their interactions with morphological properties (i.e., slope and area, land cover, and hydrological seasonality were examined to identify controlling factors and processes governing patterns of stream water quality in the upper Han River, China. Correlation analysis and stepwise multiple regression models revealed significant correlations between ions (i.e., Cl(-, SO(4(2-, Na(+ and K(+ and land cover (i.e., vegetation and bare land over the entire catchment in both high- and low-flow periods, and in the buffer zone the correlation was much more stronger in the low-flow period. Catchment with steeper slope (>15° was negatively correlated with major ions, largely due to multicollinearity of basin characteristics. Land cover within the buffer zone explained slightly less of major elements than at catchment scale in the rainy season, whereas in the dry season, land cover along the river networks in particular this within 100 m riparian zone much better explained major elements rather than this over the entire catchment. Anthropogenic land uses (i.e., urban and agriculture however could not explain water chemical variables, albeit EC, TDS, anthropogenic markers (Cl(-, NO(3(-, SO(4(2, Na(+, K(+ and Ca(2+ significantly increased during 2005-2010, which was corroborated by principal component analyses (PCA that indicated anthropogenic inputs. Observations demonstrated much higher solute concentrations in the industrial-polluted river. Our results suggested that seasonal evolution of water quality in combined with spatial analysis at multiple scales should be a vital part of identifying the controls on spatio-temporal patterns of water quality.

  8. Identifying the sources of nitrate contamination of groundwater in an agricultural area (Haean basin, Korea) using isotope and microbial community analyses

    International Nuclear Information System (INIS)

    An integrated study based on hydrogeochemical, microbiological and dual isotopic approaches for nitrate and sulfate was conducted to elucidate sources and biogeochemical reactions governing groundwater contaminants in different seasons and under different land use in a basin of Korea. The land use in the study area is comprised of forests (58.0%), vegetable fields (27.6%), rice paddy fields (11.4%) and others (3.0%). The concentrations of NO3–N and SO42− in groundwater in vegetable fields were highest with 4.2–15.2 mg L−1 and 1.6–19.7 mg L−1 respectively, whereas under paddy fields NO3–N concentrations ranged from 0 to 10.7 mg L−1 and sulfate concentrations were ~ 15 mg L−1. Groundwater with high NO3–N concentrations of > 10 mg L−1 had δ15N–NO3− values ranging from 5.2 to 5.9‰ and δ18O values of nitrate between 2.7 and 4.6‰ suggesting that the nitrate was mineralized from soil organic matter that was amended by fertilizer additions. Elevated concentrations of SO42− with δ34S–SO42− values between 1 and 6‰ in aquifers in vegetable fields indicated that a mixture of sulfate from atmospheric deposition, mineralization of soil organic matter and from synthetic fertilizers is the source of groundwater sulfate. Elevated δ18O–NO3− and δ18O–SO42− values in samples collected from the paddy fields indicated that denitrification and bacterial sulfate reduction are actively occurring removing sulfate and nitrate from the groundwater. This was supported by high occurrences of denitrifying and sulfate reducing bacteria in groundwater of the paddy fields as evidenced by 16S rRNA pyrosequencing analysis. This study shows that dual isotope techniques combined with microbial data can be a powerful tool for identification of sources and microbial processes affecting NO3− and SO42− in groundwater in areas with intensive agricultural land use. - Highlights: • Dual isotope analyses identified contaminant sources. • Aquifer

  9. Identifying the sources of nitrate contamination of groundwater in an agricultural area (Haean basin, Korea) using isotope and microbial community analyses

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Heejung [School of Earth and Environmental Sciences (BK21 SEES), Seoul National University, Seoul 151–747 (Korea, Republic of); Kaown, Dugin, E-mail: dugin1@snu.ac.kr [School of Earth and Environmental Sciences (BK21 SEES), Seoul National University, Seoul 151–747 (Korea, Republic of); Mayer, Bernhard [Department of Geoscience, University of Calgary, 2500 University Drive NW, Calgary T2N 1N4, Alberta (Canada); Lee, Jin-Yong [Department of Geology, Kangwon National University, Chuncheon 200–701 (Korea, Republic of); Hyun, Yunjung [Planning and Management Group, Korea Environment Institute, Sejong 339-007 (Korea, Republic of); Lee, Kang-Kun [School of Earth and Environmental Sciences (BK21 SEES), Seoul National University, Seoul 151–747 (Korea, Republic of)

    2015-11-15

    } and SO{sub 4}{sup 2−} in groundwater in areas with intensive agricultural land use. - Highlights: • Dual isotope analyses identified contaminant sources. • Aquifer contamination was affected by land use. • Microbial community in groundwater reflects land use. • Approach is promising for managing water quality in agricultural areas.

  10. 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.

  11. Integration of spatial datasets to support the review of hydrometric networks and the identification of representative catchments

    Directory of Open Access Journals (Sweden)

    C. L. R. Laize

    2004-01-01

    Full Text Available The rapidly growing demand for river flow data has increased pressure on hydrometric monitoring programmes to match a wide range of application-focused information needs, in particular, the identification of representative catchments. This paper investigates a novel methodology based on a Geographical Information System to support cost-effective hydrometric network management and information delivery. Raster datasets are integrated as matrices describing the relationship between variables within any given area. Matrices are then compared to index how representative catchments are of a specified reference area. Using south-east Scotland as the reference area, four applications illustrate the methodology’s potential to address a variety of issues (e.g. network rationalisation, selection of impact catchments, identification of new gauging sites. The method is implemented using elevation and land-use datasets. Keywords: spatial information, Geographical Information System, hydrometry, network management, network rationalisation, representative catchment, regionalisation

  12. Hydrogeochemistry of shallow groundwater in an upland Scottish catchment

    Science.gov (United States)

    Soulsby, C.; Chen, M.; Ferrier, R. C.; Helliwell, R. C.; Jenkins, A.; Harriman, R.

    1998-06-01

    The hydrogeochemistry of shallow groundwater has been characterized in the Allt a'Mharcaidh catchment in the Scottish Cairngorms in order to: (i) assess the spatial and temporal variation in groundwater chemistry; (ii) identify the hydrogeochemical processes regulating its evolution; and (iii) examine the influence of groundwater on the quality and quantity of stream flow. Shallow groundwater in superficial drift deposits is circumneutral (pH7·1) and base cation concentrations are enriched compared with precipitation and drainage water from overlying podzolic soils. Modelling with NETPATH suggests that the dominant geochemical processes that account for this are the dissolution of plagioclase, K-feldspar and biotite. Groundwater emerging as springs from weathered granite underlying high altitude (>900 m) alpine soils shows similar characteristics, though weathering rates are lower, probably as a result of reduced residence times and lower temperatures. Chemical hydrograph separation techniques using acid neutralizing capacity (ANC) and Si as tracers show that groundwater is the dominant source of baseflow in the catchment and also buffers the chemistry of stream water at high flows: groundwater may account for as much as 50-60% of annual runoff in the catchment. Climate and land use in the Cairngorms are vulnerable to future changes, which may have major implications for hydrogeological processes in the area.

  13. Curvature distribution within hillslopes and catchments and its effect on the hydrological response

    NARCIS (Netherlands)

    Bogaart, P.W.; Troch, P.A.A.

    2006-01-01

    Topographic convergence and divergence are first order controls on the hillslope and catchment hydrological response, as evidenced by similarity parameter analyses. Hydrological models often do not take convergence as measured by contour curvature directly into account; instead they use comparable m

  14. 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.

  15. Morphology, geology and water quality assessment of former tin mining catchment.

    Science.gov (United States)

    Ashraf, Muhammad Aqeel; Maah, Mohd Jamil; Yusoff, Ismail

    2012-01-01

    Bestari Jaya, former tin mining catchment covers an area of 2656.31 hectares comprised of four hundred and forty-two different-size lakes and ponds. The present study area comprise of 92 hectares of the catchment that include four large size lakes. Arc GIS version 9.2 used to develop bathymetric map, Global Positioning System (GPS) for hydrographical survey and flow meter was utilized for water discharge analysis (flow routing) of the catchment. The water quality parameters (pH, temperature, electric conductivity, dissolved oxygen DO, total dissolved solids TDS, chlorides, ammonium, nitrates) were analyzed by using Hydrolab. Quality assurance (QA) and quality control (QC) procedures were strictly followed throughout the field work and data analysis. Different procedures were employed to evaluate the analytical data and to check for possible transcription or dilution errors, changes during analysis, or unusual or unlikely values. The results obtained are compared with interim national water quality standards for Malaysia indicates that water quality of area is highly degraded. It is concluded that Bestri Jaya ex-mining catchment has a high pollution potential due to mining activities and River Ayer Hitam, recipient of catchment water, is a highly polluted river. PMID:22761549

  16. Morphology, Geology and Water Quality Assessment of Former Tin Mining Catchment

    Directory of Open Access Journals (Sweden)

    Muhammad Aqeel Ashraf

    2012-01-01

    Full Text Available Bestari Jaya, former tin mining catchment covers an area of 2656.31 hectares comprised of four hundred and forty-two different-size lakes and ponds. The present study area comprise of 92 hectares of the catchment that include four large size lakes. Arc GIS version 9.2 used to develop bathymetric map, Global Positioning System (GPS for hydrographical survey and flow meter was utilized for water discharge analysis (flow routing of the catchment. The water quality parameters (pH, temperature, electric conductivity, dissolved oxygen DO, total dissolved solids TDS, chlorides, ammonium, nitrates were analyzed by using Hydrolab. Quality assurance (QA and quality control (QC procedures were strictly followed throughout the field work and data analysis. Different procedures were employed to evaluate the analytical data and to check for possible transcription or dilution errors, changes during analysis, or unusual or unlikely values. The results obtained are compared with interim national water quality standards for Malaysia indicates that water quality of area is highly degraded. It is concluded that Bestri Jaya ex-mining catchment has a high pollution potential due to mining activities and River Ayer Hitam, recipient of catchment water, is a highly polluted river.

  17. Hydrological relation between two small catchments in central Poland - Zwolenka vs Zagozdzonka rivers

    Science.gov (United States)

    Nestorowicz, Anna; Banasik, Kazimierz; Gładecki, Jacek

    2010-05-01

    Hydrological relation between two small catchments in central Poland - Zwolenka vs Zagozdzonka rivers. Key words: long time hydrological data, Nature 2000 network, hydrological relation Since 1992 the European Union is implementing the European Ecological Natura 2000 Network. The main purpose of creation of Natura 2000, is to protect the natural endangered habitats and species of plants and animals across Europe characteristic to 9 regions. In Poland there are only two regions: continental and alpine. Many Nature 2000 areas are in a way connected with water and often covers small not hydrologically investigated catchments and rivers. Since, 2008 the Department of Hydraulic Engineering and Environmental Restoration, Warsaw University of Life Sciences has started a hydrological investigation in Zwoleńka river catchment which valley is a protected Nature 2000 area. One of the most important species in this area is a pond turtle which prefer the wet habitats. There is no precise hydrological data for the Zwoleńka river, however, the other Zagożdżonka river catchment which border on Zwoleńka is investigated since 1963. The main purpose of this investigation is the find the relation between this two river catchment: protected Nature 2000 with no data and carefully investigated Zagożdżonka, with long time hydrological data set.

  18. Nitrate reduction in geologically heterogeneous catchments--a framework for assessing the scale of predictive capability of hydrological models.

    Science.gov (United States)

    Refsgaard, Jens Christian; Auken, Esben; Bamberg, Charlotte A; Christensen, Britt S B; 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

    2014-01-15

    In order to fulfil the requirements of the EU Water Framework Directive nitrate load from agricultural areas to surface water in Denmark needs to be reduced by about 40%. The regulations imposed until now have been uniform, i.e. the same restrictions for all areas independent of the subsurface conditions. Studies have shown that on a national basis about 2/3 of the nitrate leaching from the root zone is reduced naturally, through denitrification, in the subsurface before reaching the streams. Therefore, it is more cost-effective to identify robust areas, where nitrate leaching through the root 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 2m, respectively, in the upper 30 m. The geological heterogeneity and uncertainty are further analysed by use of the geostatistical software TProGS by generating stochastic geological realisations that are soft conditioned against the geophysical data. Finally, the flow paths within the catchment are simulated by use of the MIKE SHE hydrological modelling system for each of the geological models generated by TProGS and the prediction uncertainty is characterised by the variance between the

  19. Developing a multi-pollutant conceptual framework for the selection and targeting of interventions in water industry catchment management schemes.

    Science.gov (United States)

    Bloodworth, J W; Holman, I P; Burgess, P J; Gillman, S; Frogbrook, Z; Brown, P

    2015-09-15

    In recent years water companies have started to adopt catchment management to reduce diffuse pollution in drinking water supply areas. The heterogeneity of catchments and the range of pollutants that must be removed to meet the EU Drinking Water Directive (98/83/EC) limits make it difficult to prioritise areas of a catchment for intervention. Thus conceptual frameworks are required that can disaggregate the components of pollutant risk and help water companies make decisions about where to target interventions in their catchments to maximum effect. This paper demonstrates the concept of generalising pollutants in the same framework by reviewing key pollutant processes within a source-mobilisation-delivery context. From this, criteria are developed (with input from water industry professionals involved in catchment management) which highlights the need for a new water industry specific conceptual framework. The new CaRPoW (Catchment Risk to Potable Water) framework uses the Source-Mobilisation-Delivery concept as modular components of risk that work at two scales, source and mobilisation at the field scale and delivery at the catchment scale. Disaggregating pollutant processes permits the main components of risk to be ascertained so that appropriate interventions can be selected. The generic structure also allows for the outputs from different pollutants to be compared so that potential multiple benefits can be identified. CaRPow provides a transferable framework that can be used by water companies to cost-effectively target interventions under current conditions or under scenarios of land use or climate change. PMID:26172105

  20. Lake-catchment systems and sediment information in Baikal district (Siberia and Mongolia)

    Institute of Scientific and Technical Information of China (English)

    KASHIWAYA Kenji

    2011-01-01

    Sediment information is closely related to a lake-catchment system. Lake Baikal and Lake Khuvsgul in the Baikal depression have shown different sedimentary trends during the past 800 ka; the sediment discharge (sedimentation rate) in Baikal basically followed the global climatic change, whereas that in Khuvsgul did not always do so. An elementary mathematical model is used to explain the difference, considering changes in the catchment area and water level. Numerical calculations based on the model suggest that sedimentary conditions are closely related to changes in the water level and erosion area, which probably had a signiifcant inlfuence on Lake Khuvsgul and little inlfuence on Lake Baikal.

  1. Changes in runoff in two neighbouring catchments in the Bohemian Forest related to climate and land cover changes

    Directory of Open Access Journals (Sweden)

    Bernsteinová Jana

    2015-12-01

    Full Text Available There is public concern that large-scale disturbances to forest cover caused by insects and storm winds in the Bohemian Forest could intensify high water flows and enhance the expected flooding risks predicted in current regional climate change scenarios. We analysed stream discharge in Upper Vydra and Große Ohe, neighbouring catchments in the Bohemian Forest, the largest contiguous forested area in Central Europe. Upper Vydra, in the Šumava National Park, and Große Ohe (including the Upper Große Ohe headwater catchment in the Bavarian Forest National Park are similar in size, but differ in land use cover and the extent of disturbed Norway spruce stands. Publicly available runoff and meteorological data (1978–2011 were examined using non-parametric trend and breakpoint analysis. Together with mapped vegetation cover changes, the results were used to address the following questions: 1 are there significant changes in the hydrological cycle and, if so, do these changes relate to 2 the extent and expansion of disturbance in forests stands and/or 3 altered precipitation dynamics and thermal conditions?

  2. Investigating source water Cryptosporidium concentration, species and infectivity rates during rainfall-runoff in a multi-use catchment.

    Science.gov (United States)

    Swaffer, Brooke A; Vial, Hayley M; King, Brendon J; Daly, Robert; Frizenschaf, Jacqueline; Monis, Paul T

    2014-12-15

    Protozoan pathogens present a significant human health concern, and prevention of contamination into potable networks remains a key focus for drinking water providers. Here, we monitored the change in Cryptosporidium concentration in source water during high flow events in a multi-use catchment. Furthermore, we investigated the diversity of Cryptosporidium species/genotypes present in the source water, and delivered an oocyst infectivity fraction. There was a positive and significant correlation between Cryptosporidium concentration and flow (ρ = 0.756) and turbidity (ρ = 0.631) for all rainfall-runoff events, despite variable source water pathogen concentrations. Cell culture assays measured oocyst infectivity and suggested an overall source water infectious fraction of 3.1%. No infectious Cryptosporidium parvum or Cryptosporidium hominis were detected, although molecular testing detected C. parvum in 7% of the samples analysed using PCR-based molecular techniques. Twelve Cryptosporidium species/genotypes were identified using molecular techniques, and were reflective of the host animals typically found in remnant vegetation and agricultural areas. The inclusion of molecular approaches to identify Cryptosporidium species and genotypes highlighted the diversity of pathogens in water, which originated from various sources across the catchment. We suggest this mixing of runoff water from a range of landuses containing diverse Cryptosporidium hosts is a key explanation for the often-cited difficulty forming strong pathogen-indicator relationships.

  3. 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. Site