Zia, Huma; Harris, Nick; Merrett, Geoff
Electronics and Computer Science, University of Southampton, United Kingdom Summary The challenge of improving water quality (WQ) is a growing global concern . Poor WQ is mainly attributed to poor water management and outdated agricultural activities. We propose that collaborative sensor networks spread across an entire catchment can allow cooperation among individual activities for integrated WQ monitoring and management. We show that sharing information on critical parameters among networks of water bodies and farms can enable identification and quantification of the contaminant sources, enabling better decision making for agricultural practices and thereby reducing contaminants fluxes. Motivation and results Nutrient losses from land to water have accelerated due to agricultural and urban pursuits . In many cases, the application of fertiliser can be reduced by 30-50% without any loss of yield . Thus information about nutrient levels and trends around the farm can improve agricultural practices and thereby reduce water contamination. The use of sensor networks for monitoring WQ in a catchment is in its infancy, but more applications are being tested . However, these are focussed on local requirements and are mostly limited to water bodies. They have yet to explore the use of this technology for catchment-scale monitoring and management decisions, in an autonomous and dynamic manner. For effective and integrated WQ management, we propose a system that utilises local monitoring networks across a catchment, with provision for collaborative information sharing. This system of networks shares information about critical events, such as rain or flooding. Higher-level applications make use of this information to inform decisions about nutrient management, improving the quality of monitoring through the provision of richer datasets of catchment information to local networks. In the full paper, we present example scenarios and analyse how the benefits of
Rose, Steve; Worrall, Peter; Rosolova, Zdenka; Hammond, Gene
Rural land management is known to affect both the generation and propagation of flooding at the local scale, but there is still a general lack of good evidence that this impact is still significant at the larger catchment scale given the complexity of physical interactions and climatic variability taking place at this level. The National Trust, in partnership with the Environment Agency, are managing an innovative project on the Holnicote Estate in south west England to demonstrate the benefits of using good rural land management practices to reduce flood risk at the both the catchment and sub-catchment scales. The Holnicote Estate is owned by the National Trust and comprises about 5,000 hectares of land, from the uplands of Exmoor to the sea, incorporating most of the catchments of the river Horner and Aller Water. There are nearly 100 houses across three villages that are at risk from flooding which could potentially benefit from changes in land management practices in the surrounding catchment providing a more sustainable flood attenuation function. In addition to the contribution being made to flood risk management there are a range of other ecosystems services that will be enhanced through these targeted land management changes. Alterations in land management will create new opportunities for wildlife and habitats and help to improve the local surface water quality. Such improvements will not only create additional wildlife resources locally but also serve the landscape response to climate change effects by creating and enhancing wildlife networks within the region. Land management changes will also restore and sustain landscape heritage resources and provide opportunities for amenity, recreation and tourism. The project delivery team is working with the National Trust from source to sea across the entire Holnicote Estate, to identify and subsequently implement suitable land management techniques to manage local flood risk within the catchments. These
Davidsen, Claus; Cardenal, Silvio Javier Pereira; Liu, Suxia;
A hydro-economic modelling approach is used to optimize reservoir management at river basin level. We demonstrate the potential of this integrated approach on the Ziya River basin, a complex basin on the North China Plain south-east of Beijing. The area is subject to severe water scarcity due to...... low and extremely seasonal precipitation, and the intense agricultural production is highly dependent on irrigation. Large reservoirs provide water storage for dry months while groundwater and the external South-to-North Water Transfer Project are alternative sources of water. An optimization model...... based on stochastic dynamic programming has been developed. The objective function is to minimize the total cost of supplying water to the users, while satisfying minimum ecosystem flow constraints. Each user group (agriculture, domestic and industry) is characterized by fixed demands, fixed water...
Jacosen, T.; Refsgaard, A.; Jacobsen, Brian H.;
agricultural production and leakage of nitrate constitute a major pollution problem with respect groundwater aquifers (drinking water), fresh surface water systems (water quality of lakes) and coastal receiving waters (eutrophication). The case study presented illustrates an advanced modelling approach applied...... in river basin management. Point sources (e.g. sewage treatment plant discharges) and distributed diffuse sources (nitrate leakage) are included to provide a modelling tool capable of simulating pollution transport from source to recipient to analyse effects of specific, localized basin water...... management plans. The paper also includes a land rent modelling approach which can be used to choose the most cost effective measures and the location of these measures. As a forerunner to the use of basin scale models in WFD basin water management plans this project demonstrates potential and limitations in...
Refsgaard, A.; Jacobsen, T.; Jacobsen, Brian H.;
intensive agricultural production and leakage of nitrate constitute a major pollution problem with respect groundwater aquifers (drinking water), fresh surface water systems (water quality of lakes) and coastal receiving waters (eutrophication). The case study presented illustrates an advanced modelling......The EU Water Framework Directive (WFD) requires an integrated approach to river basin management in order to meet environmental and ecological objectives. This paper presents concepts and full-scale application of an integrated modelling framework. The Ringkoebing Fjord basin is characterized by...... approach applied in river basin management. Point sources (e.g. sewage treatment plant discharges) and distributed diffuse sources (nitrate leakage) are included to provide a modelling tool capable of simulating pollution transport from source to recipient to analyse the effects of specific, localized...
Rivers, Mark; Clarendon, Simon; Coles, Neil
over entire catchments, for example, only reduced P losses by approximately 20%. Most importantly, changes to land use mosaics within the catchments provided great insight into the relative roles within the catchment P system of the various land uses. While dairying uses large amounts of P, the effects that dairy farm management can have at the catchment scale when these farms represent only a small proportion of the landscape are limited. The most important conclusions from the research are that: • While State and regional environmental management and regulatory agencies continue to set optimistic goals for water quality protection, this research shows that these targets are not achievable within current landscape paradigms even after broadscale BMP implementation, and that either these targets must be re-considered or that significant land use change (rather than simply improved management within current systems) must occur to meet the targets. • Catchment-scale effects of P losses at the farm scale are a complex function of P-use efficiency, landscape position and landscape footprint. Simply targetting those landuses perceived to have high nutrient loss rates does not adequately address the problem. • Catchment P management must be considered in a more inclusive and holistic way, and these assessments should be used to inform future planning policies and development plans if environmental goals as well as community expectations about the productive use of agricultural land are to be met.
Taylor, Sam; He, Yi; Hiscock, Kevin
Increasing human pressures on the natural environment through the demand for increased agricultural productivity have exacerbated and deteriorated water quality conditions within many environments due to an unbalancing of the nutrient cycle. As a consequence, increased agricultural diffuse water pollution has resulted in elevated concentrations of nutrients within surface water and groundwater bodies. This deterioration in water quality has direct consequences for the health of aquatic ecosystems and biodiversity, human health, and the use of water as a resource for public water supply and recreation. To mitigate these potential impacts and to meet commitments under the EU Drinking Water and Water Framework Directives, there is a need to improve our understanding of the impacts that agricultural land use and management practices have on water quality. Water quality models are one of the tools available which can be used to facilitate this aim. These simplified representations of the physical environment allow a variety of changes to be simulated within a catchment, including for example changes in agricultural land use and management practices, allowing for predictions of the impacts of those measures on water quality to be developed and an assessment to be made of their effectiveness in improving conditions. The aim of this research is to apply the water quality model SWAT (Soil and Water Assessment Tool) to the Wensum catchment (area 650 km2), situated in the East of England, to predict the impacts of potential changes in land use and land management practices on water quality as part of a process to select those measures that in combination will have the greatest potential to improve water quality. Model calibration and validation is conducted at three sites within the catchment against observations of river discharge and nitrate and total phosphorus loads at a monthly time-step using the optimisation algorithm SUFI-2 (Sequential Uncertainty Fitting Version 2
Famiglietti, J.S.; E. F. Wood; Sivapalan, M.; Thongs, D. J
A catchment scale water balance model is presented and used to predict evaporation from the King's Creek catchment at the First ISLSCP Field Experiment site on the Konza Prairie, Kansas. The model incorporates spatial variability in topography, soils, and precipitation to compute the land surface hydrologie fluxes. A network of 20 rain gages was employed to measure rainfall across the catchment in the summer of 1987. These data were spatially interpolated and used to drive the model during st...
Famiglietti, J. S.; Wood, E. F.; Sivapalan, M.; Thongs, D. J.
A catchment scale water balance model is presented and used to predict evaporation from the King's Creek catchment at the First ISLSCP Field Experiment site on the Konza Prairie, Kansas. The model incorporates spatial variability in topography, soils, and precipitation to compute the land surface hydrologic fluxes. A network of 20 rain gages was employed to measure rainfall across the catchment in the summer of 1987. These data were spatially interpolated and used to drive the model during storm periods. During interstorm periods the model was driven by the estimated potential evaporation, which was calculated using net radiation data collected at site 2. Model-computed evaporation is compared to that observed, both at site 2 (grid location 1916-BRS) and the catchment scale, for the simulation period from June 1 to October 9, 1987.
Troch, Peter A.; Mancini, Marco; Paniconi, Claudio; Wood, Eric F.
The validity of some of the simplifying assumptions in a conceptual water balance model is investigated by comparing simulation results from the conceptual model with simulation results from a three-dimensional physically based numerical model and with field observations. We examine, in particular, assumptions and simplifications related to water table dynamics, vertical soil moisture and pressure head distributions, and subsurface flow contributions to stream discharge. The conceptual model relies on a topographic index to predict saturation excess runoff and on Philip's infiltration equation to predict infiltration excess runoff. The numerical model solves the three-dimensional Richards equation describing flow in variably saturated porous media, and handles seepage face boundaries, infiltration excess and saturation excess runoff production, and soil driven and atmosphere driven surface fluxes. The study catchments (a 7.2 sq km catchment and a 0.64 sq km subcatchment) are located in the North Appalachian ridge and valley region of eastern Pennsylvania. Hydrologic data collected during the MACHYDRO 90 field experiment are used to calibrate the models and to evaluate simulation results. It is found that water table dynamics as predicted by the conceptual model are close to the observations in a shallow water well and therefore, that a linear relationship between a topographic index and the local water table depth is found to be a reasonable assumption for catchment scale modeling. However, the hydraulic equilibrium assumption is not valid for the upper 100 cm layer of the unsaturated zone and a conceptual model that incorporates a root zone is suggested. Furthermore, theoretical subsurface flow characteristics from the conceptual model are found to be different from field observations, numerical simulation results, and theoretical baseflow recession characteristics based on Boussinesq's groundwater equation.
Linking on-farm change to catchment response using dynamic simulation modelling: assessing the impacts of farm-scale land management change on catchment-scale phosphorus transport processes and water-quality.
Rivers, M.; Clarendon, S.
Australian Natural Resource Management and Agri-industry Development agencies have recently invested considerable resources into a number of research and development projects that have investigated the actual and potential economic, social and, particularly, environmental impacts of varying farming activities (with a strong focus on dairies) in a "catchment context". These activities have resulted in the development of a much-improved understanding of the likely impacts of changed farm management practices within the farms and regions in which they were investigated, as well as the development of a number of conceptual models which place dairy farming within this broader catchment context. The project discussed in this paper was charged with the objective of transforming these conceptual models of dairy farm nutrient management and transport processes into a more temporally and spatially dynamic model. This could then be loaded with catchment-specific data and used as a "policy support tool" to allow the Australian dairy industry to examine the potential farm and catchment-scale impacts of varying dairy farm management practices within some key dairy farming regions. This paper describes the series of dynamic models and farm management - land use scenarios which were executed to examine these issues. Models were developed, validated and calibrated for the Peel-Harvey catchment in Western Australia and the Gippsland and Latrobe (a sub-catchment of Gippsland) catchments in Victoria. Scenarios which range from simple, on-farm riparian management, through changes in fertiliser application rates, to gross changes in the land use mosaic were examined and described in terms which included changes to phosphorus (P) loss rates at the farm scale, the relative contributions to catchment P loads from dairying and, ultimately, changes to downstream water quality. A comprehensive suite of scenarios and policy options was examined but, in summary, the results indicate that whilst
Modeling greenhouse gas emissions (CO2, N2O, CH4) from managed arable soils with a fully coupled hydrology-biogeochemical modeling system simulating water and nutrient transport and associated carbon and nitrogen cycling at catchment scale
Klatt, Steffen; Haas, Edwin; Kraus, David; Kiese, Ralf; Butterbach-Bahl, Klaus; Kraft, Philipp; Plesca, Ina; Breuer, Lutz; Zhu, Bo; Zhou, Minghua; Zhang, Wei; Zheng, Xunhua; Wlotzka, Martin; Heuveline, Vincent
The use of mineral nitrogen fertilizer sustains the global food production and therefore the livelihood of human kind. The rise in world population will put pressure on the global agricultural system to increase its productivity leading most likely to an intensification of mineral nitrogen fertilizer use. The fate of excess nitrogen and its distribution within landscapes is manifold. Process knowledge on the site scale has rapidly grown in recent years and models have been developed to simulate carbon and nitrogen cycling in managed ecosystems on the site scale. Despite first regional studies, the carbon and nitrogen cycling on the landscape or catchment scale is not fully understood. In this study we present a newly developed modelling approach by coupling the fully distributed hydrology model CMF (catchment modelling framework) to the process based regional ecosystem model LandscapeDNDC for the investigation of hydrological processes and carbon and nitrogen transport and cycling, with a focus on nutrient displacement and resulting greenhouse gas emissions in a small catchment at the Yanting Agro-ecological Experimental Station of Purple Soil, Sichuan province, China. The catchment hosts cypress forests on the outer regions, arable fields on the sloping croplands cultivated with wheat-maize rotations and paddy rice fields in the lowland. The catchment consists of 300 polygons vertically stratified into 10 soil layers. Ecosystem states (soil water content and nutrients) and fluxes (evapotranspiration) are exchanged between the models at high temporal scales (hourly to daily) forming a 3-dimensional model application. The water flux and nutrients transport in the soil is modelled using a 3D Richards/Darcy approach for subsurface fluxes with a kinematic wave approach for surface water runoff and the evapotranspiration is based on Penman-Monteith. Biogeochemical processes are modelled by LandscapeDNDC, including soil microclimate, plant growth and biomass allocation
Kay, Paul; Grayson, Richard; Phillips, Martin; Stanley, Karen; Dodsworth, Alan; Hanson, Ann; Walker, Andrew; Foulger, Miles; McDonnell, Iain; Taylor, Simon
SummaryAgriculture is estimated to be responsible for 70% of nitrate and 30-50% of phosphorus pollution, contributing to ecological and water treatment problems. Despite the fact that significant gaps remain in our understanding, it is known that agricultural stewardship can be highly effective in controlling water pollution at the plot and field scales. Knowledge at the catchment scale is, to a large extent, entirely lacking though and this is of paramount concern given that the catchment is the management unit used by regulatory authorities. The few studies that have examined the impact of agricultural stewardship at the catchment scale have found that Nitrate Vulnerable Zones (NVZs) in the UK have resulted in little improvement in water quality which concurs with the current catchment study. In addition to NVZs, there was little evidence to suggest that the England Catchment Sensitive Farming Delivery Initiative had impacted water quality and suggestions have been made for improvements, such as ensuring that stewardship measures are used in key pollution source areas and their implementation and impacts are monitored more closely. This will be essential if agricultural catchment management schemes are going to provide the benefits expected of them. Nevertheless, more intensive monitoring than that carried out by regulators showed a significant trend in decreasing winter nitrate peaks in some streams which is hypothesised to be due to recent reduced inorganic fertiliser application as a result of increasing prices. It was concluded that, collectively, these findings indicate that agricultural stewardship measures have the potential to improve water quality at the catchment scale but that voluntary schemes with insufficient financial reward or regulatory pressure are unlikely to be successful.
Yoshida, T.; Masumoto, T.; Horikawa, N.; Kudo, R.; Minakawa, H.; Nawa, N.
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
La Jeunesse, I.; Romanowicz, A.; Vanclooster, M.; Rounsevell, M.
Demand and competition for water resources is continuously increasing in Europe. In recent years, many research efforts have been oriented toward the solution of specific aspects of the complex problem of water resource management. A great deal of scientific knowledge is now available in many fields, but this knowledge is often treated in isolation. The purpose of the 3-year MULINO project is to provide a tool to improve the integrated management of water resources at the catchment scale, following the requirements of the Water Framework Directive. Thus, the main objectives of the MULINO project are (1) to make a multi- disciplinary diagnosis of the main issues for local water management, (2) to conceptualise an operational decision support tool (DSS) for integrated water management, (3) to define a set of alternative water management scenarios, and (4) to exchange experience with local authorities. The underlying design of the DSS is based on the European Environment Agency's Driving Forces-Pressures-State-Impact-Responses (DPSIR) framework for reporting on environmental issues. This structure will provide the decision maker with an integrated view of the problem. This DSS is a computer system based on hydrological modelling, multi-disciplinary indicators and indices and multi-criteria evaluation procedures. Two scales are studied : the catchment scale and the European scale the DSS will be imp lemented in five European countries Belgium, Italy, Portugal, Romania and United Kingdom. GIS-based hydrological models, run within or outside of the DSS tool, make integrated simulation of multi-sectoral water uses possible. Capabilities for geographical data handling and display are embedded within the DSS to support the management of spatial data and the interface with the users. On the 700 km2 Dyle catchment situated in the centre of Belgium (50°38N 4°45E), a coupling of an integrated hydrological model (SWAT : Soil and Water Assessment Tool, Arnold et al., 1993) with
Twohig, Sarah; Pattison, Ian
Increases in sediment delivery to river channels from changes in land use and climate must be accounted for by catchment managers. Recent flooding of the Somerset Levels, UK highlighted the impacts of reduced channel capacity as a result of sedimentation. Sediment entering river systems needs to be carefully managed in order to sustainably mitigate flood risk. Geomorphological drivers have previously been neglected when proposing methods to reduce flood risk. Understanding the connections between hydrology, geomorphology and engineering is fundamental to predicating sediment transfer within river catchments and thus successfully implementing sustainable flood management. This study focuses on catchment scale fine sediment delivery, changes to channel capacity and its implications for existing flood defence infrastructure. Furthermore, fine sediment accumulations in river channels have been found to reduce water quality due to the presence of nutrients and heavy metals and degrade spawning and invertebrate habitats. Locating the sources of fine sediment within a catchment will enable catchment managers to target resources effectively at reducing sedimentation in rivers and appraise natural flood alleviation measures. This study investigates whether changes in channel capacity due to sedimentation influence flood risk of the River Eye catchment, Leicestershire. Using a combination of field, laboratory and modelling methods this study 1) identifies the sources of fine sediment within the catchment, using sediment fingerprinting techniques; 2) quantifies the spatial and temporal changes in channel capacity at a reach scale with a history of flooding in Melton Mowbray, and 3) monitors existing flood defences designed to prevent downstream sedimentation to determine the longevity and success of the sustainable flood defence scheme. These results will be used to predict the long term flood risk to the catchment, using a series of hydraulic inundation scenarios.
McDowell, Richard W; Nash, David; George, Anja; Wang, Q J; Duncan, Ruth
Quantifying and managing diffuse P losses from small catchments or at the farm scale requires detailed knowledge of farming practices and their interaction with catchment processes. However, detailed knowledge may not be available and hence modeling is required. This paper demonstrates two approaches to developing tools that assist P losses from New Zealand or Australian dairy farms. The first is largely empirical and separates sources of P within a paddock into soil, fertilizer, dung, and treading impacts (including damage to grazed pasture). This information is combined with expert knowledge of hydrological processes and potential point sources (e.g., stream crossings) to create a deterministic model that can be used to evaluate the most cost and labor efficient method of mitigating P losses. For instance, in one example, 45% of annual P lost was attributed to the application of superphosphate just before a runoff event for which a mitigation strategy could be to use a less water soluble P fertilizer. The second approach uses a combination of interviews, expert knowledge and relationships to develop a Bayesian Network that describes P exports. The knowledge integration process helped stakeholders develop a comprehensive understanding of the problem. The Network, presented in the form of a "cause and effect", diagram provided a simple, visual representation of current knowledge that could be easily applied to individual circumstances and isolate factors having the greatest influence on P loss. Both approaches demonstrate that modeling P losses and mitigation strategies does not have to cover every process or permutation and that a degree of uncertainty can be handled to create a working model of P losses at a farm or small catchment scale. PMID:19704140
Sikorska, A. E.; Wasilewicz, M.; Banasik, K.
Keywords: small detention pond, sediment deposits, reservoir silting, urban catchment Globally observed land use and climate changes have a clear impact on the sediment yields deriving from the catchment. Released sediments may originate from different point and non-point sources. Thereby it is difficult to manage and reduce sediment loads directly at the source without undertaking detailed and expensive monitoring programs. Small detention ponds are therefore frequently used water management systems in urban settlements to improve water quality at the catchment scale. Such ponds located at the outlet of small basins allow reducing sediment loads downstream. Additionally, they capture sediment-associated contaminants as heavy metals, nutrients and micropollutants. On the other hand, a sedimentation within the pond may be a severe problem because it decreases over the time its retention capacity. This is especially significant for small detention ponds, where the siltation rate is high. These ponds can loose their total capacity already after few years of their exploitation when no dredging operations are considered. Unfortunately, maintenance costs of small ponds are expensive and usually not taken into account when planning and constructing such ponds. Consequently, many small detention ponds become inefficient after an entire use of their capacity. Therefore careful planning of maintenance options is essential to keep an effectiveness of such ponds on the expected level. Within presented here study we addressed the problem of silting small detention ponds and we assessed an applicability of such ponds to manage sediment yields discharged from small urban catchments. To this end, a periodic measurement of deposited sediments within a small detention pond (1.35 ha, 5 years old, Warsaw, Poland) has been undertaken. This pond receives a polluted runoff from a small urbanized basin (30 km2), for which no routine sediment measurement exists. The spatial sediment
Selle, B.; Schwientek, M.
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
Buckingham, David; Skalka, Christian; Bongard, Josh
Infrastructure for the automatic collection of single-point measurements of snow water equivalent (SWE) is well-established. However, because SWE varies significantly over space, the estimation of SWE at the catchment scale based on a single-point measurement is error-prone. We propose low-cost, lightweight methods for near-real-time estimation of mean catchment-wide SWE using existing infrastructure, wireless sensor networks, and machine learning algorithms. Because snowpack distribution is highly nonlinear, we focus on Genetic Programming (GP), a nonlinear, white-box, inductive machine learning algorithm. Because we did not have access to near-real-time catchment-scale SWE data, we used available data as ground truth for machine learning in a set of experiments that are successive approximations of our goal of catchment-wide SWE estimation. First, we used a history of maritime snowpack data collected by manual snow courses. Second, we used distributed snow depth (HS) data collected automatically by wireless sensor networks. We compared the performance of GP against linear regression (LR), binary regression trees (BT), and a widely used basic method (BM) that naively assumes non-variable snowpack. In the first experiment set, GP and LR models predicted SWE with lower error than BM. In the second experiment set, GP had lower error than LR, but outperformed BT only when we applied a technique that specifically mitigated the possibility of over-fitting.
Echeverría Martinez, Carlos Antonio; Ruiz-Pérez, Guiomar; Francés, Félix
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.
Le Maitre, D C; Gush, M B; Dzikiti, S
There have been many studies of the diverse impacts of invasions by alien plants but few have assessed impacts on water resources. We reviewed the information on the impacts of invasions on surface runoff and groundwater resources at stand to catchment scales and covering a full annual cycle. Most of the research is South African so the emphasis is on South Africa's major invaders with data from commercial forest plantations where relevant. Catchment studies worldwide have shown that changes in vegetation structure and the physiology of the dominant plant species result in changes in surface runoff and groundwater discharge, whether they involve native or alien plant species. Where there is little change in vegetation structure [e.g. leaf area (index), height, rooting depth and seasonality] the effects of invasions generally are small or undetectable. In South Africa, the most important woody invaders typically are taller and deeper rooted than the native species. The impacts of changes in evaporation (and thus runoff) in dryland settings are constrained by water availability to the plants and, thus, by rainfall. Where the dryland invaders are evergreen and the native vegetation (grass) is seasonal, the increases can reach 300-400 mm/year. Where the native vegetation is evergreen (shrublands) the increases are ∼200-300 mm/year. Where water availability is greater (riparian settings or shallow water tables), invading tree water-use can reach 1.5-2.0 times that of the same species in a dryland setting. So, riparian invasions have a much greater impact per unit area invaded than dryland invasions. The available data are scattered and incomplete, and there are many gaps and issues that must be addressed before a thorough understanding of the impacts at the site scale can be gained and used in extrapolating to watershed scales, and in converting changes in flows to water supply system yields. PMID:25935861
Petersen, M. F.; Eriksson, E.; Binning, P. J.; Bjerg, P. L.
The water quality of surface waters is threatened by multiple anthropogenic pollutants and the large variety of pollutants challenges the monitoring and assessment of the water quality. The aim of this study was to characterize and quantify both point and diffuse sources of micropollutants impacting the water quality of a stream at catchment scale. Grindsted stream in western Jutland, Denmark was used as a study site. The stream passes both urban and agricultural areas and is impacted by severe groundwater contamination in Grindsted city. Along a 12 km reach of Grindsted stream, the potential pollution sources were identified including a pharmaceutical factory site with a contaminated old drainage ditch, two waste deposits, a wastewater treatment plant, overflow structures, fish farms, industrial discharges and diffuse agricultural and urban sources. Six water samples were collected along the stream and analyzed for general water quality parameters, inorganic constituents, pesticides, sulfonamides, chlorinated solvents, BTEXs, and paracetamol and ibuprofen. The latter two groups were not detected. The general water quality showed typical conditions for a stream in western Jutland. Minor impacts by releases of organic matter and nutrients were found after the fish farms and the waste water treatment plant. Nickel was found at concentrations 5.8 - 8.8 μg/l. Nine pesticides and metabolites of both agricultural and urban use were detected along the stream; among these were the two most frequently detected and some rarely detected pesticides in Danish water courses. The concentrations were generally consistent with other findings in Danish streams and in the range 0.01 - 0.09 μg/l; except for metribuzin-diketo that showed high concentrations up to 0.74 μg/l. The groundwater contamination at the pharmaceutical factory site, the drainage ditch and the waste deposits is similar in composition containing among others sulfonamides and chlorinated solvents (including vinyl
Rooij, G. H.
Soil water is confined behind the menisci of its water-air interface. Catchment-scale fluxes (groundwater recharge, evaporation, transpiration, precipitation, etc.) affect the matric potential, and thereby the interface curvature and the configuration of the phases. In turn, these affect the fluxes (except precipitation), creating feedbacks between pore-scale and catchment-scale processes. Tracking pore-scale processes beyond the Darcy scale is not feasible. Instead, for a simplified ...
K. J. Van Meter
Full Text Available Rainwater harvesting (RWH, the small-scale collection and storage of runoff for irrigated agriculture, is recognized as a sustainable strategy for ensuring food security, especially in monsoonal landscapes in the developing world. In south India, these strategies have been used for millennia to mitigate problems of water scarcity. However, in the past 100 years many traditional RWH systems have fallen into disrepair due to increasing dependence on groundwater. This dependence has contributed to an accelerated decline in groundwater resources, which has in turn led to increased efforts at the state and national levels to revive older RWH systems. Critical to the success of such efforts is an improved understanding of how these ancient systems function in contemporary landscapes with extensive groundwater pumping and shifted climatic regimes. Knowledge is especially lacking regarding the water-exchange dynamics of these RWH "tanks" at tank and catchment scales, and how these exchanges regulate tank performance and catchment water balances. Here, we use fine-scale water-level variation to quantify daily fluxes of groundwater, evapotranspiration (ET, and sluice outflows in four tanks over the 2013 northeast monsoon season in a tank cascade that covers a catchment area of 28 km2. At the tank scale, our results indicate that groundwater recharge and irrigation outflows comprise the largest fractions of the tank water budget, with ET accounting for only 13–22 % of the outflows. At the scale of the cascade, we observe a distinct spatial pattern in groundwater-exchange dynamics, with the frequency and magnitude of groundwater inflows increasing down the cascade of tanks. The significant magnitude of return flows along the tank cascade leads to the most downgradient tank in the cascade having an outflow-to capacity ratio greater than 2. The presence of tanks in the landscape dramatically alters the catchment water balance, with runoff decreasing by
Van Meter, K. J.; Basu, N. B.; McLaughlin, D. L.; Steiff, M.
Rainwater harvesting (RWH), the small-scale collection and storage of runoff for irrigated agriculture, is recognized as a sustainable strategy for ensuring food security, especially in monsoonal landscapes in the developing world. In south India, these strategies have been used for millennia to mitigate problems of water scarcity. However, in the past 100 years many traditional RWH systems have fallen into disrepair due to increasing dependence on groundwater. This dependence has contributed to an accelerated decline in groundwater resources, which has in turn led to increased efforts at the state and national levels to revive older RWH systems. Critical to the success of such efforts is an improved understanding of how these ancient systems function in contemporary landscapes with extensive groundwater pumping and shifted climatic regimes. Knowledge is especially lacking regarding the water-exchange dynamics of these RWH "tanks" at tank and catchment scales, and how these exchanges regulate tank performance and catchment water balances. Here, we use fine-scale water-level variation to quantify daily fluxes of groundwater, evapotranspiration (ET), and sluice outflows in four tanks over the 2013 northeast monsoon season in a tank cascade that covers a catchment area of 28 km2. At the tank scale, our results indicate that groundwater recharge and irrigation outflows comprise the largest fractions of the tank water budget, with ET accounting for only 13-22 % of the outflows. At the scale of the cascade, we observe a distinct spatial pattern in groundwater-exchange dynamics, with the frequency and magnitude of groundwater inflows increasing down the cascade of tanks. The significant magnitude of return flows along the tank cascade leads to the most downgradient tank in the cascade having an outflow-to capacity ratio greater than 2. The presence of tanks in the landscape dramatically alters the catchment water balance, with runoff decreasing by nearly 75 %, and
Loperfido, J. V.; Noe, Gregory B.; Jarnagin, S. Taylor; Hogan, Dianna M.
Urban stormwater runoff remains an important issue that causes local and regional-scale water quantity and quality issues. Stormwater best management practices (BMPs) have been widely used to mitigate runoff issues, traditionally in a centralized manner; however, problems associated with urban hydrology have remained. An emerging trend is implementation of BMPs in a distributed manner (multi-BMP treatment trains located on the landscape and integrated with urban design), but little catchment-scale performance of these systems have been reported to date. Here, stream hydrologic data (March, 2011-September, 2012) are evaluated in four catchments located in the Chesapeake Bay watershed: one utilizing distributed stormwater BMPs, two utilizing centralized stormwater BMPs, and a forested catchment serving as a reference. Among urban catchments with similar land cover, geology and BMP design standards (i.e. 100-year event), but contrasting placement of stormwater BMPs, distributed BMPs resulted in: significantly greater estimated baseflow, a higher minimum precipitation threshold for stream response and maximum discharge increases, better maximum discharge control for small precipitation events, and reduced runoff volume during an extreme (1000-year) precipitation event compared to centralized BMPs. For all catchments, greater forest land cover and less impervious cover appeared to be more important drivers than stormwater BMP spatial pattern, and caused lower total, stormflow, and baseflow runoff volume; lower maximum discharge during typical precipitation events; and lower runoff volume during an extreme precipitation event. Analysis of hydrologic field data in this study suggests that both the spatial distribution of stormwater BMPs and land cover are important for management of urban stormwater runoff. In particular, catchment-wide application of distributed BMPs improved stream hydrology compared to centralized BMPs, but not enough to fully replicate forested
Locatelli, Luca; Gabriel, S; Bockhorn, Britta; Mark, O.; Mikkelsen, Peter Steen; Arnbjerg-Nielsen, Karsten; Kjølby, M. J.; Taylor, Heidi; Larsen, H.; Steensen Blicher, Anne; Binning, Philip John
Stormwater management using Water Sensitive Urban Design (WSUD) is expected to be part of future drainage systems. This project aimed to develop a set of hydraulic models of the Harrestrup Å catchment (close to Copenhagen) in order to demonstrate the importance of modeling WSUDs at different scales, ranging from models of an individual soakaway up to models of a large urban catchment. The models were developed in Mike Urban with a new integrated soakaway model. A small-scale individual soakaw...
Locatelli, Luca; Gabriel, S.; Bockhorn, Britta;
Stormwater management using Water Sensitive Urban Design (WSUD) is expected to be part of future drainage systems. This project aimed to develop a set of hydraulic models of the Harrestrup Å catchment (close to Copenhagen) in order to demonstrate the importance of modeling WSUDs at different scales...... infiltration is > 80% of the annual precipitation even for small soakaway volumes. A local scale (<10ha) model examined the benefit of employing soakaways and detention basins for reducing flooding. A baseline scenario was set up and the areas which must be disconnected in order to avoid flooding identified...
In the EU-project FOOTPRINT three pesticide risk assessment and management tools were developed, for use by three distinct end-user communities at three different spatial scales: policy makers and registration authorities at the national/EU scale, water managers and local authorities at the catchment scale, and farmers and extension advisors at the farm scale. The three FOOTPRINT tools share the same underlying science (e.g. a database of agro-environmental scenarios occurring in the EU) and provide an integrated solution to pesticide risk assessment and management in the EU. The tools allow users to: i) identify the dominant pathways and sources of pesticide contamination in the landscape, ii) estimate levels of pesticide concentrations in ground- and surface water, and iii) make assessments of how the implementation of mitigation strategies would reduce pesticide contamination. Furthermore, the exposure estimates provided by the tools can be easily compared with ecotoxicological endpoints or legal thresholds such as the drinking water limit. In the tool FOOT-CRS (Catchment and Regional Scale), which has been programmed as an add-on in ArcGIS, the emphasis is on i) identifying the areas most contributing to the contamination of water resources by pesticides, and ii) defining and/or optimising action plans at the scale of the catchment. In contrast to the national-scale tool FOOT-NES, where pesticide concentrations in hypothetical edge-of-field surface water bodies are calculated, FOOT-CRS uses the actual surface water network. For the calculation of pesticide inputs into surface waters via surface runoff and erosion, a routing to the surface water network is performed on a grid basis, and the pesticide load reduction during transport in overland flow by reinfiltration or redeposition is explicitly calculated. Subsequently, the fractions of pesticide surface runoff loss and pesticide erosion loss from a cell that finally reach the surface water network are computed
Lu, Shenglan; Trolle, Dennis; Blicher-Mathiesen, Gitte; Estrup Andersen, Hans
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.
Kay, D; Anthony, S; Crowther, J; Chambers, B J; Nicholson, F A; Chadwick, D; Stapleton, C M; Wyer, M D
The European Union Water Framework Directive requires that Management Plans are developed for individual River Basin Districts. From the point of view of faecal indicator organisms (FIOs), there is a critical need for screening tools that can provide a rapid assessment of the likely FIO concentrations and fluxes within catchments under base- and high-flow conditions, and of the balance ('source apportionment') between agriculture- and sewage-derived sources. Accordingly, the present paper reports on: (1) the development of preliminary generic models, using water quality and land cover data from previous UK catchment studies for assessing FIO concentrations, fluxes and source apportionment within catchments during the summer bathing season; (2) the calibration of national land use data, against data previously used in the models; and (3) provisional FIO concentration and source-apportionment assessments for England and Wales. The models clearly highlighted the crucial importance of high-flow conditions for the flux of FIOs within catchments. At high flow, improved grassland (and associated livestock) was the key FIO source; FIO loadings derived from catchments with high proportions of improved grassland were shown to be as high as from urbanized catchments; and in many rural catchments, especially in NW and SW England and Wales, which are important areas of lowland livestock (especially dairy) farming, ≥ 40% of FIOs was assessed to be derived from agricultural sources. In contrast, under base-flow conditions, when there was little or no runoff from agricultural land, urban (i.e. sewerage-related) sources were assessed to dominate, and even in rural areas the majority of FIOs were attributed to urban sources. The results of the study demonstrate the potential of this type of approach, particularly in light of climate change and the likelihood of more high-flow events, in underpinning informed policy development and prioritization of investment. PMID:19717181
Glanville, K.; Ryan, T.; Tomlinson, M.; Muriuki, G.; Ronan, M.; Pollett, A.
Immediate and foreseeable threats to groundwater-dependent ecosystems (GDEs) are widely acknowledged, many linked to altered groundwater regimes including changes in groundwater flow, flux, pressure, level and/or quality (Eamus et al. in Aust J Bot 54:97-114, 2006a). Natural resource managers and other decision-makers often lack sufficient information at an appropriate scale to understand the groundwater dependency of ecosystems and ensure that GDEs are adequately considered in decision-making processes. This paper describes a new catchment scale mapping method for GDEs based on the integration of local expert knowledge with detailed spatial datasets to delineate GDEs at a scale compatible with management and planning activities. This overcomes one of the key criticisms often levelled at broader scale mapping methods—that information from local and regional experts, with significant understanding of landscape processes and ecosystems, is not incorporated into the datasets used by decision-makers. Expert knowledge is conveyed in the form of pictorial conceptual models representing the components, processes and interrelationships of groundwater within a catchment and the ecosystems dependent on it. Each mapped GDE is linked to a pictorial conceptual model and a mapping rule-set to provide decision-makers with valuable information about where, how and why GDEs exist in a landscape.
Petersen, Mette Fjendbo; Eriksson, Eva; Binning, Philip John;
The water quality of surface waters is threatened by multiple anthropogenic pollutants and the large variety of pollutants challenges the monitoring and assessment of the water quality. The aim of this study was to characterize and quantify both point and diffuse sources of micropollutants...
Pattison, Ian; Lane, Stuart; Hardy, Richard; Reaney, Sim
workshop, whereby a map of the catchment was laid out and locations where each scenario could feasibly be implemented were drawn on. This was combined with an analysis of historical maps to identify past land covers and a catchment walkover survey to put modelling work in the real world context. The land management scenarios were tested using hydrological and hydraulic models. Landscape scale changes, such as the effects of compaction and afforestation were tested using a catchment scale hydrological mode, CRUM2D. Channel scale changes, such as re-meandering and floodplain storage were tested using the 1D hydraulic model, iSIS, by altering channel cross sections and creating spills between the channel and floodplain. It is expected that the channel modification and floodplain storage scenarios will have the greatest impact on flooding both at the local and catchment scales. The landscape scale changes are more diffuse and therefore their impact is expected to be less significant. Although, early analysis indicates that the spatial location of changes strongly influences their effect on flooding.
Stevens, Laura A.; Straneo, Fiamma; Das, Sarah B.; Plueddemann, Albert J.; Kukulya, Amy L.; Morlighem, Mathieu
Measurements of near-ice (autonomous underwater vehicle as close as 150 m from the ice-ocean interface of the Saqqarliup sermia-Sarqardleq Fjord system, West Greenland, with modeled and observed subglacial discharge locations and magnitudes. We find evidence of two main types of subsurface glacially modified water (GMW) with distinct properties and locations. The two GMW locations also align with modeled runoff discharged at separate locations along the grounded margin corresponding with two prominent subcatchments beneath Saqqarliup sermia. Thus, near-ice observations and subglacial discharge routing indicate that runoff from this glacier occurs primarily at two discrete locations and gives rise to two distinct glacially modified waters. Furthermore, we show that the location with the largest subglacial discharge is associated with the lighter, fresher glacially modified water mass. This is qualitatively consistent with results from an idealized plume model.
J. C. Rozemeijer
Clean water is essential for our existence on earth. In areas with intensive agricultural land use, such as The Netherlands, groundwater and surface water resources are threatened. The leaching of agrochemicals from agricultural fields leads to contamination of drinking water resources and toxic algae blooms and loss of biodiversity in surface waters. Water quality managers are responsible for the detection of water quality problems and for taking appropriate measures. Therefore, a lot of the...
Hinderer, J.; Hector, B.; Séguis, L.; Descloitres, M.; Cohard, J.; Boy, J.; Calvo, M.; Rosat, S.; Riccardi, U.; Galle, S.
Water storage changes (WSC) are investigated by the mean of gravity monitoring in Djougou, northern Benin, in the frame of the GHYRAF (Gravity and Hydrology in Africa) project. In this area, WSC are 1) part of the control system for evapotranspiration (ET) processes, a key variable of the West-African monsoon cycle and 2) the state variable for resource management, a critical issue in storage-poor hard rock basement contexts such as in northern Benin. We show the advantages of gravity monitoring for analyzing different processes in the water cycle involved at various time and space scales, using the main gravity sensors available today (FG5 absolute gravimeter, superconducting gravimeter -SG- and CG5 micro-gravimeter). The study area is also part of the long-term observing system AMMA-Catch, and thus under intense hydro-meteorological monitoring (rain, soil moisture, water table level, ET ...). Gravity-derived WSC are compared at all frequencies to hydrological data and to hydrological models calibrated on these data. Discrepancies are analyzed to discuss the pros and cons of each approach. Fast gravity changes (a few hours) are significant when rain events occur, and involve different contributions: rainfall itself, runoff, fast subsurface water redistribution, screening effect of the gravimeter building and local topography. We investigate these effects and present the statistical results of a set of rain events recorded with the SG installed in Djougou since July 2010. The intermediate time scale of gravity changes (a few days) is caused by ET and both vertical and horizontal water redistribution. The integrative nature of gravity measurements does not allow to separate these different contributions, and the screening from the shelter reduces our ability to retrieve ET values. Also, atmospheric corrections are critical at such frequencies, and deserve some specific attention. However, a quick analysis of gravity changes following rain events shows that the
2. Research Coordination Meeting of the Coordinated Research Project on Integrated Analytical Approaches to Assess Indicators of the Effectiveness of Pesticide Management Practices at the Catchment Scale (D5.20.35); Vienna, Austria; 9-13 February 2009
The Second Research Coordination Meeting (RCM) of Coordinated Research Project (CRP) on Integrated Analytical Approaches to Assess Indicators of the Effectiveness of Pesticide Management Practices at the Catchment Scale was held at IAEA Headquarters in Vienna, Austria, from 9-13 February 2009. The meeting was attended by research contract/agreement holders from Argentina, Australia, Brazil, Bulgaria, Chile, China, Costa Rica, Cyprus, Ecuador, Germany, Kenya, India and the Philippines, as well as observers from Costa Rica and Slovakia. The objectives of the meeting were to share and disseminate the results of the first two years of the programme, to agree on a work plan for the next two years of the project and to strengthen the role of participating laboratories in the assessment of the implementation of good agricultural practices (GAP). Specifically, to: - consolidate the network of laboratories to assess indicators of pesticide management practices in water and soil/sediment samples; - disseminate information about the results obtained from the first two years of work; - revise individual work plans for the next two years of the project; - fine tune the risk assessment results using the pesticide impact rating index (PIRI); - update skills in the analysis of pesticide residues in water/soil/sediments; - disseminate information about bioassays relevant to the CRP, and; - familiarize participants with the use of flow meters, GPS and GIS and new LIMS developments
Pullan, S P; Whelan, M J; Rettino, J; Filby, K; Eyre, S; Holman, I P
This paper describes the development and application of IMPT (Integrated Model for Pesticide Transport), a parameter-efficient tool for predicting diffuse-source pesticide concentrations in surface waters used for drinking water supply. The model was applied to a small UK headwater catchment with high frequency (8h) pesticide monitoring data and to five larger catchments (479-1653km(2)) with sampling approximately every 14days. Model performance was good for predictions of both flow (Nash Sutcliffe Efficiency generally >0.59 and PBIAS operational and strategic risk assessments. PMID:27151500
K. J. Van Meter; Basu, N.B.; D. L. McLaughlin; Steiff, M.
Rainwater harvesting (RWH), the small-scale collection and storage of runoff for irrigated agriculture, is recognized as a sustainable strategy for ensuring food security, especially in monsoonal landscapes in the developing world. In south India, these strategies have been used for millennia to mitigate problems of water scarcity. However, in the past 100 years many traditional RWH systems have fallen into disrepair due to increasing dependence on groundwat...
Sulis, Mauro; Shrestha, Prabhakar; Keune, Jessica; Steinke, Sandra; Diederich, Malte; Schween, Jan; Crewell, Susanne; Simmer, Clemens; Kollet, Stefan
Fully coupled hydrological models close the water and energy cycles while accounting for the dynamic feedbacks between the subsurface, land surface, and atmosphere compartments of terrestrial systems. Diagnoses of their predictive capabilities require spatio-temporal coherent data sets including states and fluxes across the soil-vegetation-atmosphere continuum. This study presents an extensive comparison between numerical simulations carried out using a novel integrated hydrological modeling platform (TerrSysMP) and a suite of cross-compartmental observations obtained from intensive field campaigns and continuous monitoring over the Rur catchment in western Germany during the HOPE experiment (April-May 2013). The observations encompass amongst others rainfall estimates from several X-band radars, atmospheric integrated water vapor estimates from microwave radiometers, radiation and turbulent fluxes at the land surface, and soil moisture retrieval from cosmic-ray probes. A detailed analysis of the radiation components indicates that TerrSysMP systematically overestimates incoming shortwave due to a cloudiness effect, but underestimates incoming longwave due to a lower simulated atmospheric water vapor content. Screening of observed and simulated data for clear sky conditions also reveals mismatches between surface albedo at certain locations within the catchment. Moreover, a preliminary cross-comparison of precipitation and soil moisture suggests that overall the model is able to reproduce catchment dynamics reasonably well while pronounced discrepancies between model and observations were observed in the mountainous region due to the lack of detailed soil parameterization (i.e., soil organic content) and the underestimation of some rainfall events.
Botta, Fabrizio; Chevreuil, Marc; Blanchoud, Hélène
The general use of pesticides in the Orge Basin, located in the southern part of the Paris suburb (France), is damaging surface water quality. Consequently, an increase in the water supply costs is registered by the water supply agencies that are situated downstream the Orge confluence with the Seine River. In this catchment, high uses of glyphosate are registered for fallow fields (upstream part) and for roadway weed control (downstream part). The proportion of glyphosate coming from these two zones was not well known, along with the double source of its metabolite AMPA originated from the degradation of some detergent phosphonates. The aim of this work was firstly to identify the potential sources of glyphosate and AMPA in urban sectors (such as sewerage system inputs) and in agricultural areas and to quantify the origins of urban pesticides pathways towards surface waters at the basin scale. The new approach of this project was to collect information at three different scales to establish a first step of modeling. At the basin scale, 1 year of surface water monitoring at the outlet of the Orge River was useful to establish the inputs towards the Seine River. At the urban catchment scale, the investigations have permitted to record glyphosate and AMPA loads transferred by storm waters and by wastewaters. Loads were estimated during and out of application calendar, in different hydrological conditions such as rainfall with high intensity or dry conditions. Impact of WWTP on surface water was also demonstrated. The third phase of this work was the interpretation of agricultural inputs from two different agricultural catchments of the Orge River. The results showed the impact of urban uses of glyphosate upon the Orge River contamination with annual loads from 100 times higher from the urban zone than from the agricultural one. Storm sewers were recognized to be the main way for glyphosate transfer towards surface waters. A budget of glyphosate and AMPA inputs and
Full Text Available The integration of water management goals in protected wetland areas agriculturally managed in an intensive manner recalls the comparison of apples (ecological values and oranges (economic dimension of agriculture. Sustainable wetland management frequently fails if environmental features are not referred to as ecosystem services and quantified in economic terms. In our hydrological-economical study on floodplain wetlands located in the Lower Basin of the Biebrza Valley, we attempt to quantify the monetary value of water storage in the floodplain during flood phenomena as an important ecosystem service. The unit monetary value of water storage in the catchment of Biebrza Valley was assessed on the basis of small artificial water reservoirs, constructed in recent years and located in the area of research, and reached 0.53 EUR·m−3·year−1. In a GIS-based study on hydrological floodplain processes in the years 1995–2011, we assessed the average annual volume of active water storage in the floodplain which reached 10.36 M m3 year−1, giving a monetary value of EUR 5.49 million per annum. We propose that the methodology presented in our analysis could be applied as water storage subsidies in valuable floodplains, to prevent their deterioration originating from agriculture intensification.
V. A. Bell
Full Text Available A simple two-dimensional rainfall model, based on advection and conservation of mass in a vertical cloud column, is investigated for use in short-term rainfall and flood forecasting at the catchment scale under UK conditions. The model is capable of assimilating weather radar, satellite infra-red and surface weather observations, together with forecasts from a mesoscale numerical weather prediction model, to obtain frequently updated forecasts of rainfall fields. Such data assimilation helps compensate for the simplified model dynamics and, taken together, provides a practical real-time forecasting scheme for catchment scale applications. Various ways are explored for using information from a numerical weather prediction model (16.8 km grid within the higher resolution model (5 km grid. A number of model variants is considered, ranging from simple persistence and advection methods used as a baseline, to different forms of the dynamic rainfall model. Model performance is assessed using data from the Wardon Hill radar in Dorset for two convective events, on 10 June 1993 and 16 July 1995, when thunderstorms occurred over southern Britain. The results show that (i a simple advection-type forecast may be improved upon by using multiscan radar data in place of data from the lowest scan, and (ii advected, steady-state predictions from the dynamic model, using 'inferred updraughts', provides the best performance overall. Updraught velocity is inferred at the forecast origin from the last two radar fields, using the mass-balance equation and associated data and is held constant over the forecast period. This inference model proves superior to the buoyancy parameterisation of updraught employed in the original formulation. A selection of the different rainfall forecasts is used as input to a catchment flow forecasting model, the IH PDM (Probability Distributed Moisture model, to assess their effect on flow forecast accuracy for the 135 km2 Brue catchment
Barnes, Mhari; Quinn, Paul; Bathurst, James; Birkinshaw, Stephen
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
Ballard, C. E.; Bulygina, N.; McIntyre, N.; Wheater, H. S.
Much of our knowledge about the changes in hydrology related to land use and land management is limited to the very small scale (e.g. changes in water retention properties, interception and runoff processes); however, we are generally most interested in the associated changes in flow regime at the catchment scale. A key methodological challenge is therefore how to upscale information about local scale changes. We present a model upscaling procedure that aims to quantify the changes in peak flows at multiple scales related to localised tree planting. The procedure divides the catchment into a number of hydrological response units, which are each classified based on soil types and land management. For each hydrological response unit, a physics-based model is developed, incorporating our understanding of hydrological processes and properties. The outputs from these physics-based models are used to train simpler “meta-models”, which are then incorporated into a semi-distributed catchment model. In this way, our understanding of local changes in physical properties can be incorporated into a more flexible and computationally efficient catchment scale conceptual model. This procedure previously performed well when supported by a multi-scale monitoring programme for a 12km2 catchment. The applicability of the procedure is now examined for a 260km2 catchment without supporting multi-scale monitoring. Without local data, physics-based models are developed a priori using information from the literature and qualitative field observations. We explore the significance of the uncertainties due to this lack of data and also uncertainties related to the upscaling procedure itself, particularly examining the identifiability of the predicted effects at multiple scales. Based on our findings we comment on the strengths and limitations of physics-based modelling and the upscaling procedure in terms of ability to predict catchment-scale impacts of local land management
Tozer, Carly R.; Vance, Tessa R.; Roberts, Jason L.; Kiem, Anthony S.; Curran, Mark A. J.; Moy, Andrew D.
Paleoclimate research indicates that the Australian instrumental climate record (˜ 100 years) does not cover the full range of hydroclimatic variability that is possible. To better understand the implications of this on catchment-scale water resources management, a 1013-year (1000-2012 common era (CE)) annual rainfall reconstruction was produced for the Williams River catchment in coastal eastern Australia. No high-resolution paleoclimate proxies are located in the region and so a teleconnection between summer sea salt deposition recorded in ice cores from East Antarctica and rainfall variability in eastern Australia was exploited to reconstruct the catchment-scale rainfall record. The reconstruction shows that significantly longer and more frequent wet and dry periods were experienced in the preinstrumental compared to the instrumental period. This suggests that existing drought and flood risk assessments underestimate the true risks due to the reliance on data and statistics obtained from only the instrumental record. This raises questions about the robustness of existing water security and flood protection measures and has serious implications for water resources management, infrastructure design and catchment planning. The method used in this proof of concept study is transferable and enables similar insights into the true risk of flood/drought to be gained for other paleoclimate proxy poor regions for which suitable remote teleconnected proxies exist. This will lead to improved understanding and ability to deal with the impacts of multi-decadal to centennial hydroclimatic variability.
Ford, C. R.; Vose, J.
Forested watersheds, an important provider of ecosystems services related to water supply, can have their structure, function, and resulting streamflow substantially altered by land use and land cover. Using a retrospective analysis and synthesis of long-term climate and streamflow data (75 years) from six watersheds differing in management histories we explored whether streamflow, and thus evapotranspiration, responded differently to variation in annual temperature and extreme precipitation than unmanaged watersheds. We used a hybrid modeling approach that incorporated terms for the classic paired watershed regression, the response of the vegetation regrowth, and the interaction of vegetation regrowth and precipitation. We show significant increases in temperature and the frequency of extreme wet and dry years since the 1980s. Response models explained almost all streamflow variability (R2adj > 0.99). In all cases, changing land use altered streamflow. Observed watershed responses differed significantly in wet and dry extreme years in all but a stand managed as a coppice forest. Converting deciduous stands to pine altered the streamflow response to extreme annual precipitation the most; the apparent frequency of observed extreme wet years decreased on average by 7-fold. This effect was attributable partially to increased interception, but also to increased transpiration in the pine stand compared to the unmanaged, deciduous hardwood stand as indicated by sap flow studies on individual species. This increased soil water storage may reduce flood risk in wet years, but create conditions that could exacerbate drought. Forest management can potentially mitigate extreme annual precipitation associated with climate change; however, offsetting effects suggest the need for spatially-explicit analyses of risk and vulnerability, as well as an increased understanding of the relative contributions of interception and transpiration across species and community types. To address
Fryirs, Kirstie; Gore, Damian
River bed colmation layers clog the interstices of gravel-bed rivers, impeding the vertical exchange of water and nutrients that drives ecosystem function in the hyporheic zone. In catchments where fine-grained sediment supply has increased since human disturbance, understanding sediment provenance and the (dis)connectivity of supply allows practitioners to target sediment source problems and treat them within catchment management plans. Release of alluvial fine-grained sediment from channel bank erosion since European settlement has resulted in the formation of a colmation layer along the upper Hunter River at Muswellbrook, eastern Australia. X-ray fluorescence spectrometry (XRF) and X-ray diffractometry (XRD) are used to determine the elemental and mineralogical signatures of colmation layer and floodplain sediment sources across this 4480 km2 catchment. This sediment tracing technique is used to construct a picture of how suspended sediment supply and (dis)connectivity operates in this catchment. In this system, the primary source areas are subcatchments in which sediments are stored largely in partly confined floodplain pockets, but from which sediment supply is unimpeded and directly connected to the receiving reach. Subcatchments in which alluvial sediment storage is significant — and which contain large, laterally unconfined valleys — are essentially 'switched off' or disconnected from the receiving reach. This is because large sediment sinks act to trap fine-grained sediment before it reaches the receiving reach, forming a buffer along the sediment conveyor belt. Given the age structure of floodplains in the receiving reach, this pattern of source area contributions and (dis)connectivity must have occurred throughout the Holocene.
Destouni, G.; Baresel, C.
Mine waste deposits from historic and active mining within the Swedish Dal River catchment are sources of heavy metals that may pollute groundwater and surface water in the catchment, as well as the Baltic Sea. Implemented and planned mine waste remediation measures are based on environmental legislation that handles different sources, in this case the mine waste sites, uniformly. The new EU Water Framework Directive (WFD) demands new tools for water quality management and decision-making within a catchment, including quantification of catchment-scale economic efficiency in chosen remediation measures, the allocation of which may then be non-uniform among the different sources of a certain water pollutant in a catchment. We present a cost-minimization model for determining cost-effective mine waste remediation allocation in the Dal River catchment, in order to achieve targeted zinc, copper and cadmium load reductions to selected recipients, including the Dal River itself. We consider various, practically feasible remediation measures and designs, including soil and water covering of sources, and downstream wetland construction close to or at compliance boundaries (CBs). We calculate the cost-efficient measure allocation, and associated total and marginal costs for minimum-cost compliance to different environmental targets (ETs; in terms of metal load reduction) and CB locations (recipients), and for different scenarios of technological efficiency, cost and lifetime. Total abatement cost for achieving a certain ET (load reduction) may then be as high for a local water environment as for the Dal River (entire catchment-scale), thus implying much higher marginal costs for the former, local compliance. The WFD allows for the possibility to use heavily modified waters, for instance close to sources, as pollutant sinks, and focus remediation on achieving good water quality in downstream, more practically restorable water bodies. The active choice of CB location is then
Baborowski, Martina; Einax, Jürgen W.
With the implementation of European Water Frame Work Directive (EU-WFD), the pollution sources in the River Elbe were assessed by the River Basin Community Elbe (RBC Elbe). Contaminated old sediments played the most significant role for inorganic and organic pollution. In terms of further improvement of the water quality in the river system, a prioritization of the known pollution sources is necessary, with respect to the expected effect in the case of their remediation. This requires information on mobility of contaminated sediments. To create a tool that allows the assessment of pollution trends in the catchment area, event based flood investigations were carried out at a sampling site in the Middle Elbe. The investigations were based on a comparable, discharge related sampling strategy. Four campaigns were performed between 1995 and 2006. The majority of the investigated 16 elements (>80%) studied more intensively in 2006 reached its maximum concentration during the first five days of the event. Only the concentrations of B, Cl-, and U declined with increasing discharge during the flood. The aim of the study was to verify that each flood event is characterized by an internal structure of the water quality. This structure is formed by the appearance of maximum values of water quality parameters at different times during the event. It could be detected by descriptive and multivariate statistical methods. As a result, internal structure of the water quality during the flood was influenced primarily by the source of the metals in the catchment area and its distance from the sampling point. The transport of metals in dissolved, colloidal or particulate form and changes of their ratios during the flood were however, not decisive for the formation of the structure. Our results show that the comparison of the structures obtained from events in different years is indicative of the pollution trend in the catchment area. Exemplarily the trend of the metal pollution in the
Stevens, L. A.; Straneo, F.; Das, S. B.; Plueddemann, A. J.; Kukulya, A. L.; Morlighem, M.
Measurements of near-ice (Autonomous Underwater Vehicle as close as 150 m from the ice/ocean interface of the Sarqardliup sermia/Sarqardleq Fjord system, West Greenland, with modeled and observed subglacial discharge locations and magnitudes. We find evidence of two main types of subsurface glacially modified water localized in space and with distinct properties that are consistent with runoff discharged at two locations along the grounded margin. These locations, in turn, correspond with two prominent subglacial subcatchments beneath Sarqardliup sermia. Thus, near-ice observations and subglacial discharge routing indicate that subglacial discharge from this glacier occurs at only two primary locations and gives rise to two distinct glacially modified waters. Furthermore, we show that the location with the largest discharge flux is associated with the lighter, fresher glacially modified watermass. This is qualitatively consistent with results from an idealized plume model.
Wade, A J; Jackson, B M; Butterfield, D
The Integrated Catchment Model of Nitrogen (INCA-N) was applied to the River Lambourn, a Chalk river-system in southern England. The model's abilities to simulate the long-term trend and seasonal patterns in observed stream water nitrate concentrations from 1920 to 2003 were tested. This is the first time a semi-distributed, daily time-step model has been applied to simulate such a long time period and then used to calculate detailed catchment nutrient budgets which span the conversion of pasture to arable during the late 1930s and 1940s. Thus, this work goes beyond source apportionment and looks to demonstrate how such simulations can be used to assess the state of the catchment and develop an understanding of system behaviour. The mass-balance results from 1921, 1922, 1991, 2001 and 2002 are presented and those for 1991 are compared to other modelled and literature values of loads associated with nitrogen soil processes and export. The variations highlighted the problem of comparing modelled fluxes with point measurements but proved useful for identifying the most poorly understood inputs and processes thereby providing an assessment of input data and model structural uncertainty. The modelled terrestrial and instream mass-balances also highlight the importance of the hydrological conditions in pollutant transport. Between 1922 and 2002, increased inputs of nitrogen from fertiliser, livestock and deposition have altered the nitrogen balance with a shift from possible reduction in soil fertility but little environmental impact in 1922, to a situation of nitrogen accumulation in the soil, groundwater and instream biota in 2002. In 1922 and 2002 it was estimated that approximately 2 and 18 kg N ha(-1) yr(-1) respectively were exported from the land to the stream. The utility of the approach and further considerations for the best use of models are discussed. PMID:18538825
Bricker, Stephanie; Bloomfield, John; Gooddy, Daren; MacDonald, David; Ward, Rob
There are significant groundwater resources in the Thames Basin (Figure 1) supporting approximately 40 per cent of public water supply. Additionally many of the rivers in the catchment are supported by groundwater from the underlying aquifers. Effective management of both groundwater resources and groundwater-dependent ecosystems requires a good understanding of how our aquifers behave. We must also consider how these systems will respond to future changes, in particular climat...
Tozer, C. R.; Vance, T. R.; Roberts, J.; Kiem, A. S.; Curran, M. A. J.; Moy, A. D.
Paleoclimate research indicates that the instrumental climate record (~100 years in Australia) does not cover the full range of hydroclimatic variability possible. To better understand the implications of this for catchment-scale water resources management, an annual rainfall reconstruction is produced for the Williams River catchment in coastal eastern Australia. No high resolution palaeoclimate proxies are located in the region and so a teleconnection between summer sea salt deposition recorded in ice cores from East Antarctica and rainfall variability in eastern Australia was exploited to reconstruct 1013 years of rainfall (AD 1000-2012). The reconstruction shows that significantly longer and more frequent wet and dry periods were experienced in the preinstrumental compared to the instrumental period. This suggests that existing drought and flood risk assessments underestimate the true risks due to the reliance on data and statistics obtained from only the instrumental record. This raises questions about the robustness of existing water security and flood protection measures and has serious implications for water resources management, infrastructure design, and catchment planning. The method used in this proof of concept study is transferable and enables similar insights into the true risk of flood/drought to be gained for other locations that are teleconnected to East Antarctica. This will lead to improved understanding and ability to deal with the impacts of multidecadal to centennial hydroclimatic variability.
Queyrel, Wilfried; Habet, Florence; Blanchoud, Hélène; Schott, Céline
Pesticide applications lead to contamination risks of environmental compartments causing harmful effects on water resource used for drinking water. Pesticide fate modeling is assumed to be a relevant approach to study pesticide dissipation at the catchment scale. Simulations of five herbicides (atrazine, simazine, isoproturon, chlortoluron, metolachor) and one metabolite (DEA) were carried out with the crop model STICS over a 23-year period (1990-2012). The model application was performed usi...
Globally river sediment associated contaminants, most notably heavy metals, radionuclides, Polychlorinated Biphenyls (PCBs), Organochlorine pesticides (OCs) and phosphorous, constitute one the most significant long-term risks to ecosystems and human health. These can impact both urban and rural areas and, because of their prolonged environmental residence times, are major sources of secondary pollution if contaminated soil and sediment are disturbed by human activity or by natural processes such as water or wind erosion. River catchments are also the primary source of sediment-associated contaminants to the coastal zone, and to the ocean, and an understanding of the factors that control contaminated sediment fluxes and delivery in river systems is essential for effective environmental management and protection. In this paper the catchment-scale controls of sediment-associated contaminant dispersal are reviewed, including climate-related variations in flooding regime, land-use change, channel engineering, restoration and flood defence. Drawing on case studies from metal mining impacted catchments in Bolivia (Río Pilcomayo), Spain (Río Guadiamar), Romania (River Tisa) and the UK (River Swale) some improved methodologies for identifying, tracing, modelling and managing contaminated river sediments are proposed that could have more general application in similarly affected river systems worldwide.
Zheng, Donghai; Van der Velde, Rogier; Su, Zhongbo; Wen, Jun; Wang, Xin; Booij, Martijn J.; Hoekstra, Arjen Y.; Lv, Shihua; Zhang, Yu; Ek, Michael B.
Noah model physics options validated for the source region of the Yellow River (SRYR) are applied to investigate their ability in reproducing runoff at the catchment scale. Three sets of augmentations are implemented affecting descriptions of (i) turbulent and soil heat transport (Noah-H), (ii) soil water flow (Noah-W), and (iii) frozen ground processes (Noah-F). Five numerical experiments are designed with the three augmented versions, a control run with default model physics and a run with all augmentations (Noah-A). Each experiment is set up with vegetation and soil parameters from Weather Research and Forecasting data set, soil organic matter content from China Soil Database, 0.1° atmospheric forcing data from Institute of Tibetan Plateau Research (Chinese Academy of Sciences), and initial equilibrium model states achieved using a single-year recurrent spin-up. In situ heat flux, soil temperature (Ts), and soil moisture (θ) profile measurements are available for point-scale assessment, whereas monthly streamflow is utilized for the catchment-scale evaluation. The comparison with point measurements shows that the augmentations invoked with Noah-H resolve issues with the heat flux and Ts simulation and Noah-W mitigates deficiencies in the θ simulation, while Noah-A yields improvements for both simulated surface energy and water budgets. In contrast, Noah-F has a minor effect. Also, at catchment scale, the best model performance is found for Noah-A leading to a base flow-dominated runoff regime, whereby the surface runoff contribution remains significant. This study highlights the need for a complete description of vertical heat and water exchanges to correctly simulate the runoff in the seasonally frozen and high-altitude SRYR at the catchment scale.
Van Loon, Anne; Tijdeman, Erik; Wanders, Niko; Van Lanen, Henny; Teuling, Adriaan; Uijlenhoet, Remko
The upscaling of the understanding of hydrological processes from the catchment scale to the global scale is not straightforward, especially not for hydrological extremes as floods and droughts. For large-scale water resources management, information on the development and persistence of soil moisture and hydrological droughts is crucial. The characteristics of these droughts (i.e. duration and severity) vary around the world and are dependent on climate and catchment properties. In this study, we investigated climate controls on drought propagation (i.e. the translation of meteorological conditions to a soil moisture drought and/or hydrological drought) by isolating forcing effects from effects of catchment properties. We used a conceptual hydrological model, forced by the WATCH forcing data, that was run for 1271 grid cells distributed over the global climate zones. The precipitation that was used as input, and soil moisture storage and subsurface discharge that were outcomes of the model, were then analysed with a well-known drought identification method (variable threshold level method). Drought characteristics duration and standardised deficit (deficit below the smoothed monthly-varying threshold, divided by the mean of the variable for that grid cell) were determined for each drought event. These drought characteristics were clustered per subclimate type and combined into bivariate probability density fields. The shape and orientation of these density fields provide information on the propagation of drought in different climate zones. Drought propagation features that are apparent on the catchment scale, such as pooling (meteorological droughts are merged into a prolonged hydrological drought) and attenuation (the damping effect of stores on the drought signal), were reproduced in all climate zones. But also seasonal drought types that can have severe impacts on the catchment scale (e.g. rain-to-snow-season drought) leave a pronounced signal in the density
Clapcott, Joanne E.; Goodwin, Eric O.; Harding, Jon S.
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.
Hansen, A.; Refsgaard, J.; Christensen, B. S.; Jensen, K. H.
Nitrate leaching from agricultural areas and the resulting pollution of groundwater and surface waters is one of the largest challenges in water resources management in Denmark. Nitrate can however be naturally degraded under anaerobic conditions and several studies have shown that degradation in the saturated zone removes more than 50% of the nitrate leaching in Danish catchments. For degradation of nitrate to occur in the saturated zone, nitrate must be transported under the redox interface and a correct simulation of the small-scale flow patterns within a catchment is therefore important in nitrate models. The general findings in Danish nitrate modeling studies are that the models perform well at catchment scale, but the predictability of the models decreases at smaller scale. Thus the model predictions are highly uncertain at small scale and the models cannot at present predict areas within a catchment, where the majority of the nitrate is brought under the interface and thus degraded, and areas, where nitrate is transported directly to streams and lakes without any significant reduction. The objective of this study is to test if the small scale performance of a catchment scale nitrate model can be improved by including small scale observation data in the calibration procedure. The study area is the clayey catchment to Lillebæk stream (4.7 km2), located on the island of Funen in Denmark. Due to the presence of clayey top soils subsurface drains are installed and in consequence the stream discharge is highly dominated by drain flow. An integrated transient hydrological model based on the MIKE SHE code has been developed for the study area. The model has been calibrated against hydraulic head measurements and stream discharge measurements from two stations, one covering most of the catchment and the other station approximately half, using the parameter estimator code PEST. Acceptable model performance has been achieved at catchment scale calibrating the model
Flores Orozco, Adrian; Gallistl, Jakob; Schlögel, Ingrid; Chwatal, Werner; Oismüller, Markus; Blöschl, Günter
The characterization of hydrogeological properties in the subsurface with high resolution across space and time scales is critical to improve our understanding of water flow and transport processes. However, to date, hydrogeological investigations are mainly performed through well-tests or the analysis of samples, thus, limiting the spatial resolution of the investigation. To properly capture heterogeneities in the subsurface controlling surface-groundwater interactions, modern hydrogeological studies require the development of innovative investigation techniques that permit to gain continuous information about subsurface state with high spatial and temporal resolution at different scales: from the pore-space all the way to the catchment. To achieve this, we propose the conduction of geophysical surveys, in particular field-scale Spectral Induced Polarization (SIP) imaging measurements. SIP images provide information about the complex electrical conductivity (CEC), which is controlled by important hydrogeological parameters, such as porosity, water content and the chemical properties of the pore-water. Here, we present imaging results collected at the catchment scale (approximately 66 ha), which permitted to gain detailed information about the spatial variability of hydrogeological parameters at different scales. The heterogeneities observed in the geophysical images revealed consistency with independent information collected at the study area. In addition to this, and taking into account that different geophysical methods yield information about different properties and at diverse scales, interpretation of the SIP images was improved by incorporation of complementary measurements, such as: ElectroMagnetic Induction (EMI), Ground Penetrating Radar (GPR), Multichannel Analysis of Surface-Waves (MASW) and Seismic Refraction-Reflection (SRR).
Orr, Alison; Nitsche, Janka; Archbold, Marie; Deakin, Jenny; Ofterdinger, Ulrich; Flynn, Raymond
Characterising catchment scale biogeochemical processes controlling nitrate fate in groundwater constitutes a fundamental consideration when applying programmes of measures to reduce risks posed by diffuse agricultural pollutants to water quality. Combining hydrochemical analyses with nitrate isotopic data and physical hydrogeological measurements permitted characterisation of biogeochemical processes influencing nitrogen fate and transport in the groundwater in two fractured bedrock aquifers with contrasting hydrogeology but comparable nutrient loads. Hydrochemical and isotopic analyses of groundwater samples collected from moderately fractured, diffusely karstified limestone indicated nitrification controlled dissolved nitrogen fate and delivery to aquatic receptors. By contrast nitrate concentrations in groundwater were considerably lower in a low transmissivity highly lithified sandstone and pyrite-bearing shale unit with patchy subsoil cover. Geophysical and hydrochemical investigations showed shallower intervals contained hydraulically active fractures where denitrification was reflected through lower nitrogen levels and an isotopic enrichment ratio of 1.7 between δ(15)N and δ(18)O. Study findings highlight the influence of bedrock hydrogeological conditions on aqueous nitrogen mobility. Investigation results demonstrate that bedrock conditions need to be considered when implementing catchment management plans to reduce the impact of agricultural practices on the quality of groundwater and baseflow in receiving rivers. Nitrate isotopic signatures in the groundwater of a freely draining catchment underlain by a karstified aquifer and a poorly draining aquifer with a low transmissivity aquifer. PMID:27432726
Read, Daniel S; Gweon, Hyun S; Bowes, Michael J; Newbold, Lindsay K; Field, Dawn; Bailey, Mark J; Griffiths, Robert I
Lotic ecosystems such as rivers and streams are unique in that they represent a continuum of both space and time during the transition from headwaters to the river mouth. As microbes have very different controls over their ecology, distribution and dispersion compared with macrobiota, we wished to explore biogeographical patterns within a river catchment and uncover the major drivers structuring bacterioplankton communities. Water samples collected across the River Thames Basin, UK, covering the transition from headwater tributaries to the lower reaches of the main river channel were characterised using 16S rRNA gene pyrosequencing. This approach revealed an ecological succession in the bacterial community composition along the river continuum, moving from a community dominated by Bacteroidetes in the headwaters to Actinobacteria-dominated downstream. Location of the sampling point in the river network (measured as the cumulative water channel distance upstream) was found to be the most predictive spatial feature; inferring that ecological processes pertaining to temporal community succession are of prime importance in driving the assemblages of riverine bacterioplankton communities. A decrease in bacterial activity rates and an increase in the abundance of low nucleic acid bacteria relative to high nucleic acid bacteria were found to correspond with these downstream changes in community structure, suggesting corresponding functional changes. Our findings show that bacterial communities across the Thames basin exhibit an ecological succession along the river continuum, and that this is primarily driven by water residence time rather than the physico-chemical status of the river. PMID:25238398
Calamita, Giuseppe; Perrone, Angela; Satriani, Antonio; Brocca, Luca; Moramarco, Tommaso
present a correlation and a regression analysis conducted both on punctual measurements and on their spatial averages. The results show that the resistivity method can be conveniently applied for soil moisture retrieval with a fairly good accuracy. The capability of this technique to obtain information for the whole soil profile suggests its use to better investigate the role of soil moisture dynamics at catchment scale and its influence on the rainfall-runoff processes.
Calamita, Giuseppe; Perrone, Angela; Satriani, Antonio; Brocca, Luca; Moramarco, Tommaso
-CNR institute in Tito Scalo (south Italy). One measurement every two days were performed on average, in particular 44 sampling events during 80 days. In both case we present a correlation and a regression analysis conducted both on punctual measurements and on their spatial averages. The results show that the resistivity method can be conveniently applied for soil moisture retrieval with a fairly good accuracy. The capability of this technique to obtain information for the whole soil profile suggests its use to better investigate the role of soil moisture dynamics at catchment scale and its influence on the rainfall-runoff processes.
Full Text Available In this study we propose an uspcaling approach to derive time series of (a REW scale state variables, and (b effective REW scale soil hydraulic functions to test and parameterise models based on the REW approach. To this end we employed a physically based hydrological model, that represents the typical patterns and structures in the study catchment, and has previously been shown to reproduce observed runoff response and state dynamics well. This landscape- and process-compatible model is used to simulate numerical drainage and wetting experiments. The effective soil water retention curve and soil hydraulic conductivity curve are derived using the spatially averaged saturation and capillary pressure as well as averaged fluxes. When driven with observed boundary conditions during a one year simulation the model is used to estimate how the spatial pattern of soil moisture evolved during this period in the catchment. The time series of the volume integrated soil moisture is deemed as best estimate for the average catchment scale soil moisture. The approach is applied to the extensively monitored Weiherbach catchment in Germany. A sensitivity analysis showed that catchment scale model structures different from the landscape- and process compatible one yielded different times series of average catchment scale soil moisture and where not able to reproduce the observed rainfall runoff response. Hence, subscale typical heterogeneity leaves a clear fingerprint in the time series of average catchment scale saturation. In case of the Weiherbach catchment local scale heterogeneity of ks could be neglected and a simple representation of the typical hillslope scale patterns of soil types and macroporosity was sufficient for obtaining effective REW scale soil hydraulic functions. Both the effective soil hydraulic functions and time series of catchment scale saturation turned out to be useful to parameterise and test the CREW model, which is based on the REW
Poulsen, J. R.; Sebok, E.; Duque, C; Tetzlaff, D.; P. K. Engesgaard
Detecting, quantifying and understanding groundwater discharge to streams are crucial for the assessment of water, nutrient and contaminant exchange at the groundwater–surface water interface. In lowland agricultural catchments with significant groundwater discharge this is of particular importance because of the risk of excess leaching of nutrients to streams. Here we aim to combine hydraulic and tracer methods from point-to-catchment scale to assess the temporal and spatia...
Moorhouse, H. L.; McGowan, S.; Jones, M.; Brayshaw, S.; Barker, P.; Leavitt, P.
A catchment-scale palaeolimnological investigation of sedimentary algal pigments spanning the past ~200 years was undertaken on lakes which drain into Windermere, England's largest and longest lake. We aimed to determine the relative influence of past regional (climatic, atmospheric deposition) and local (land-use, hydrological modification, point-source pollution) drivers of algal community change by comparing three fertile lowland lakes (Blelham Tarn, Esthwaite Water and Rydal Water) and two upland tarns (Stickle and Easedale Tarns) to better inform a catchment-wide management strategy for Windermere. Drivers of change at the upland sites included atmospheric acid deposition, climatic change and structural modifications caused by dam installation, whereas the influence of agriculture and point-source pollution is greater in the lakes in the lowland parts of the catchment. As a result, contrasting algal responses were noted in the lakes. For example, the cyanobacterial pigment zeaxanthin and the cryptophte pigment alloxanthin increased at Stickle Tarn (359% and 321% respectively) corresponding with the establishment of a dam at the outflow of the tarn in 1838. However, post-1900's the concentration of these pigments declined both at Stickle and at Easedale Tarn coincident with increased storm events and in the later decades of the century (~1980s onwards) decreases in acid deposition. In the lowland sites the cyanobacterial pigment aphanizophyll increased by 400-7000% and the indicator of total algal production β-carotene increased as much as six-fold indicating a substantial degradation in water quality and the onset of cyanobacterial blooms since the 1950's. In the lowland sites, degradation of water quality was closely linked to sewage installations and treatment work upgrades during the 1950's-70's and intensification of agricultural practices most notably increases in sheep stocking densities, which expanded in the 1950's. In lowland lakes with a higher
Coates, Victoria; Pattison, Ian
Upscaling land management signals observed at the point scale to the regional scale is challenging for three reasons. Individual catchments are unique and at the point scale land management signals are spatially and temporally variable, depending on topography, soil characteristics and on the individual characteristics of a rainfall event. However at larger scales land management effects diffuse and climatic or human induced signals have a larger impact. This does not mean that there is no influence on river flows, just that the effect is not discernible. Land management practices in different areas of the catchment vary spatially and temporally and their influence on the flood hydrograph will be different at different points within the catchment. Once the water enters the river, the land management effects are disturbed further by hydrodynamic and geomorphological dispersion. Pastoral agriculture is the dominant rural land cover in the UK (40% is classified as improved/ semi-natural grassland - Land Cover Map 2007). The intensification of agriculture has resulted in greater levels of soil compaction associated with higher stocking densities in fields. Natural flood management is the alteration, restoration or use of landscape features to reduce flood risk. Soil compaction has been shown to change the partitioning of rainfall into runoff. However the link between locally observed hydrological changes and catchment scale flood risk has not yet been proven. This paper presents the results of a hydrological modelling study on the impact of soil compaction on downstream flood risk. Field experiments have been conducted in multiple fields in the River Skell catchment, in Yorkshire, UK (area of 120km2) to determine soil characteristics and compaction levels under different types of land-use. We use this data to parameterise and validate the Distributed Physically-based Connectivity of Runoff model. A number of compaction scenarios have been tested that represent
Zhao, Jie; Xu, Zongxue; Singh, Vijay P.
The root zone storage capacity (Sr) greatly influences runoff generation, soil water movement, and vegetation growth and is hence an important variable for ecological and hydrological modelling. However, due to the great heterogeneity in soil texture and structure, there seems to be no effective approach to monitor or estimate Sr at the catchment scale presently. To fill the gap, in this study the Mass Curve Technique (MCT) was improved by incorporating a snowmelt module for the estimation of Sr at the catchment scale in different climatic regions. The "range of perturbation" method was also used to generate different scenarios for determining the sensitivity of the improved MCT-derived Sr to its influencing factors after the evaluation of plausibility of Sr derived from the improved MCT. Results can be showed as: (i) Sr estimates of different catchments varied greatly from ∼10 mm to ∼200 mm with the changes of climatic conditions and underlying surface characteristics. (ii) The improved MCT is a simple but powerful tool for the Sr estimation in different climatic regions of China, and incorporation of more catchments into Sr comparisons can further improve our knowledge on the variability of Sr. (iii) Variation of Sr values is an integrated consequence of variations in rainfall, snowmelt water and evapotranspiration. Sr values are most sensitive to variations in evapotranspiration of ecosystems. Besides, Sr values with a longer return period are more stable than those with a shorter return period when affected by fluctuations in its influencing factors.
Poulsen, J B; Sebok, E.; Duque, C; Tetzlaff, D.; P. K. Engesgaard
Detecting, quantifying, and understanding groundwater discharge to streams are crucial for the assessment of water, nutrient and contaminant exchange at the surface water–groundwater interface. In lowland agricultural catchments with significant groundwater discharge this is of particular importance because of the risk of excess leaching of nutrients to streams. Here we aim to combine hydraulic and tracer methods from point to catchment scale to assess the ...
The Joint FAO/IAEA Division has been technically responsible for technical assistance projects aimed at improving water management practices in the following developing Member States: Argentina, Bulgaria, Chile, Costa Rica, Egypt, Greece, India, Ivory Coast, Kenya, Lebanon, Morocco, Niger, Nigeria, Pakistan, Peru, Republic of Korea, Romania, Senegal, Sri Lanka, Sudan, Syria, Tanzania, Turkey, Uganda and Zambia. The Division has also contributed to the improvement of the efficiency of water use through the implementation of three 5-year co-ordinated research programmes. Participants from eight to 15 countries have conducted research towards a common goal of improving nuclear techniques in water-use efficiency studies and developing practices to increase the food produced from a unit of irrigation water or rainfall. In many cases this was the first time such techniques have been used in the above countries. It was thus necessary to provide expert assistance to train local counterparts in the safe and efficient use of the equipment. Training courses have also been held in more advanced countries to familiarize young scientists from developing countries with the most modern techniques in soil/water research. Results obtained through the nuclear techniques aided research programmes will, when applied in farmers' fields on irrigated land, lead to increased yields, to reduced losses of nutrients through leaching below the rooting zone, and to conserving soil through avoiding the accumulation of salts close to the soil surface. Under rainfed agriculture, research results would help controlling erosion, conserving water, and ensuring sustained production at acceptable yield levels
Bellarby, Jessica; Surridge, Ben; Haygarth, Philip M.; Lai, Xin; Zhang, Guilong; Song, Xiaolong; Zhou, Jianbin; Meng, Fanqiao; Shen, Jianbo; Rahn, Clive; Smith, Laurence; Burke, Sean
Diffuse water pollution from agriculture (DWPA) represents a significant challenge in both the UK and China. The UK has developed policies and practices which seek to mitigate DWPA, yet the risks and adverse impacts of DWPA remain widespread. In contrast, China's past priorities have largely focussed on food security, with an emphasis on increasing food production through high fertiliser application rates with little attention being paid to enhanced nutrient export from land to water and to air. This has contributed to severe environmental problems which are only now beginning to be recognised and addressed. We have prepared nutrient balances (phosphorus and nitrogen) in contrasting agricultural production systems at sub-catchment scale within China and the UK. These draw from a variety of sources ranging from general yearly statistics collected by the respective government to farm surveys. Our aim is to use the resulting nutrient balances to underpin the sharing of knowledge and innovation to mitigate DWPA in both nations. In the UK, the case studies focus on the three Demonstration Test Catchment locations, covering a range of livestock and arable production systems across England. Here, the high frequency monitoring of phosphorus river loads enables the cross-validation of the simple nutrient budget approaches applied in this study. In China, our case studies span kiwi orchard, fruit and vegetable solar greenhouse systems, double cropped rice-wheat and wheat-maize production systems. Substantial differences in nutrient stocks and flows exist between individual production systems both across and within the two countries. These differences will be expressed along the source-mobilisation-delivery-impact continuum that underpins our budgets for both phosphorus and nitrogen. We will present the phosphorus cycles of some case studies and highlight their challenges and relevance at sub-catchment scale. Based on our nutrient budgets, general recommendations can be
Collins, A.; Lloyd, C.; Freer, J. E.; Johnes, P.; Stirling, M.
One of the biggest challenges in catchment water quality management is tackling the problem of reducing water pollution from agriculture whilst ensuring food security nationally. Improvements to catchment management plans are needed if we are to enhance biodiversity and maintain good ecological status in freshwater ecosystems, while producing enough food to support a growing global population. In order to plan for a more sustainable and secure future, research needs to quantify the uncertainties and understand the complexities in the source-mobilisation-delivery-impact continuum of pollution and nutrients at all scales. In the UK the Demonstration Test Catchment (DTC) project has been set up to improve water quality specifically from diffuse pollution from agriculture by enhanced high resolution monitoring and targeted mitigation experiments. The DTC project aims to detect shifts in the baseline trend of the most ecologically-significant pollutants resulting from targeted on-farm measures at field to farm scales and assessing their effects on ecosystem function. The DTC programme involves three catchments across the UK that are indicative of three different typologies and land uses. This paper will focus on the Hampshire Avon DTC, where a total of 12 parameters are monitored by bank-side stations at two sampling sites, including flow, turbidity, phosphate and nitrate concentrations at 30 min resolution. This monitoring is supported by daily resolution sampling at 5 other sites and storm sampling at all locations. Part of the DTC project aims to understand how observations of water quality within river systems at different temporal resolutions and types of monitoring strategies enable us to understand and detect changes over and above the natural variability. Baseline monitoring is currently underway and early results show that high-resolution data is essential at this sub-catchment scale to understand important process dynamics. This is critical if we are to design
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.
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 temperature methods as well as event hydrograph separation techniques at the sub-catchment scale. The results show that almost 88% of the river discharge consists of groundwater. Vegetation dependencies on groundwater were analyzed 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 on groundwater as the dominant water 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 water demand for socio-economical development and to prevent desertification, more water use efficient crops such as sorghum, barley and millet should be promoted to reduce the consumptive water use for irrigation. Willow trees should be used as wind-breaks in croplands and along roads, and dry resistant and less water use intensive plants (for instance native bushes should be used to vegetate sand dunes.
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.
Fan, Linfeng; Lehmann, Peter; Or, Dani
Spatial variations in soil properties affect key hydrological processes, yet their role in soil mechanical response to hydro-mechanical loading is rarely considered. This study aims to fill this gap by systematically quantifying effects of spatial variations in soil type and initial water content on rapid rainfall-induced shallow landslide predictions at the hillslope- and catchment-scales. We employed a physically-based landslide triggering model that considers mechanical interactions among soil columns governed by strength thresholds. At the hillslope scale, we found that the emergence of weak regions induced by spatial variations of soil type and initial water content resulted in early triggering of landslides with smaller volumes of released mass relative to a homogeneous slope. At the catchment scale, initial water content was linked to a topographic wetness index, whereas soil type varied deterministically with soil depth considering spatially correlated stochastic components. Results indicate that a strong spatial organization of initial water content delays landslide triggering, whereas spatially linked soil type with soil depth promoted landslide initiation. Increasing the standard deviation and correlation length of the stochastic component of soil type increases landslide volume and hastens onset of landslides. The study illustrates that for similar external boundary conditions and mean soil properties, landslide characteristics vary significantly with soil variability, hence it must be considered for improved landslide model predictions.
S. N. Gosling
. However, they are relatively small in comparison to the range of projections across the seven GCMs. Hence, for the six catchments and seven GCMs we considered, climate model structural uncertainty is greater than the uncertainty associated with the type of hydrological model applied. Moreover, shifts in the seasonal cycle of runoff with climate change are represented similarly by both hydrological models, although for some catchments the monthly timing of high and low flows differs. This implies that for studies that seek to quantify and assess the role of climate model uncertainty on catchment-scale runoff, it may be equally as feasible to apply a GHM (Mac-PDM.09 here as it is to apply a CHM, especially when climate modelling uncertainty across the range of available GCMs is as large as it currently is. Whilst the GHM is able to represent the broad climate change signal that is represented by the CHMs, we find however, that for some catchments there are differences between GHMs and CHMs in mean annual runoff due to differences in potential evapotranspiration estimation methods, in the representation of the seasonality of runoff, and in the magnitude of changes in extreme (Q5, Q95 monthly runoff, all of which have implications for future water management issues.
Peche, Aaron; Fuchs, Lothar; Spönemann, Peter; Graf, Thomas; Neuweiler, Insa
Keywords: pipe leakage, urban hydrogeology, catchment scale, OpenGeoSys, HYSTEM-EXTRAN Wastewater leakage from subsurface sewer pipe defects leads to contamination of the surrounding soil and groundwater (Ellis, 2002; Wolf et al., 2004). Leakage rates at pipe defects have to be known in order to quantify contaminant input. Due to inaccessibility of subsurface pipe defects, direct (in-situ) measurements of leakage rates are tedious and associated with a high degree of uncertainty (Wolf, 2006). Proposed catchment-scale models simplify leakage rates by neglecting unsaturated zone flow or by reducing spatial dimensions (Karpf & Krebs, 2013, Boukhemacha et al., 2015). In the present study, we present a physically based 3-dimensional numerical model incorporating flow in the pipe network, in the saturated zone and in the unsaturated zone to quantify leakage rates on the catchment scale. The model consists of the pipe network flow model HYSTEM-EXTAN (itwh, 2002), which is coupled to the subsurface flow model OpenGeoSys (Kolditz et al., 2012). We also present the newly developed coupling scheme between the two flow models. Leakage functions specific to a pipe defect are derived from simulations of pipe leakage using spatially refined grids around pipe defects. In order to minimize computational effort, these leakage functions are built into the presented numerical model using unrefined grids around pipe defects. The resulting coupled model is capable of efficiently simulating spatially distributed pipe leakage coupled with subsurficial water flow in a 3-dimensional environment. References: Boukhemacha, M. A., Gogu, C. R., Serpescu, I., Gaitanaru, D., & Bica, I. (2015). A hydrogeological conceptual approach to study urban groundwater flow in Bucharest city, Romania. Hydrogeology Journal, 23(3), 437-450. doi:10.1007/s10040-014-1220-3. Ellis, J. B., & Revitt, D. M. (2002). Sewer losses and interactions with groundwater quality. Water Science and Technology, 45(3), 195
Loinaz, Maria Christina; Davidsen, Hasse Kampp; Butts, Michael;
including temperature data in an integrated flow model calibration because temperature data provide additional constraints on the flow sources and volumes. Simulations show that a reduction of 10% in the groundwater flow to the Silver Creek Basin can cause average and maximum temperature increases in Silver......Changes in natural stream temperature levels can be detrimental to the health of aquatic ecosystems. Water use and land management directly affect the distribution of diffuse heat sources and thermal loads to streams, while riparian vegetation and geomorphology play a critical role in how thermal...... loads are buffered. In many areas, groundwater flow is a significant contribution to river flow, particularly during low flows and therefore has a strong influence on stream temperature levels and dynamics. However, previous stream temperature models do not properly simulate how surface water...
M. A. Pedder
Full Text Available A deterministic forecast of surface precipitation involves solving a time-dependent moisture balance equation satisfying conservation of total water substance. A realistic solution needs to take into account feedback between atmospheric dynamics and the diabatic sources of heat energy associated with phase changes, as well as complex microphysical processes controlling the conversion between cloud water (or ice and precipitation. Such processes are taken into account either explicitly or via physical parameterisation schemes in many operational numerical weather prediction models; these can therefore generate precipitation forecasts which are fully consistent with the predicted evolution of the atmospheric state as measured by observations of temperature, wind, pressure and humidity. This paper reviews briefly the atmospheric moisture balance equation and how it may be solved in practice. Solutions are obtained using the Meteorological Office Mesoscale version of its operational Unified Numerical Weather Prediction (NWP model; they verify predicted precipitation rates against catchment-scale values based on observations collected during an Intensive Observation Period (IOP of HYREX. Results highlight some limitations of an operational NWP forecast in providing adequate time and space resolution, and its sensitivity to initial conditions. The large-scale model forecast can, nevertheless, provide important information about the moist dynamical environment which could be incorporated usefully into a higher resolution, ‘storm-resolving’ prediction scheme. Keywords: Precipitation forecasting; moisture budget; numerical weather prediction
Booij, Martijn J.; Oldhoff, Ruben J. J.; Rustanto, Andry
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
Beltrame, Ludovica; Carbonin, Daniele; Galelli, Stefano; Castelletti, Andrea
Population growth, water scarcity and climate change are three major factors making the understanding of variations in water availability increasingly important. Therefore, reliable medium-to-long range forecasts of streamflows are essential to the development of water management policies. To this purpose, recent modelling efforts have been dedicated to seasonal and inter-annual streamflow forecasts based on the teleconnection between "at-site" hydro-meteorological processes and low frequency climate fluctuations, such as El Niño Southern Oscillation (ENSO). This work proposes a novel procedure for first detecting the impact of ENSO on hydro-meteorological processes at the catchment scale, and then assessing the potential of ENSO indicators for building medium-to-long range statistical streamflow prediction models. Core of this procedure is the adoption of the Iterative Input variable Selection (IIS) algorithm that is employed to find the most relevant forcings of streamflow variability and derive predictive models based on the selected inputs. The procedure is tested on the Columbia (USA) and Williams (Australia) Rivers, where ENSO influence has been well-documented, and then adopted on the unexplored Red River basin (Vietnam). Results show that IIS outcomes on the Columbia and Williams Rivers are consistent with the results of previous studies, and that ENSO indicators can be effectively used to enhance the streamflow forecast models capabilities. The experiments on the Red River basin show that the ENSO influence is less pronounced, inducing little effects on the basin hydro-meteorological processes.
Molina Navarro, Eugenio; Trolle, Dennis; Martínez-Pérez, Silvia;
Water scarcity and water pollution constitute a big challenge for water managers in the Mediterranean region today and will exacerbate in a projected future warmer world, making a holistic approach for water resources management at the catchment scale essential. We expanded the Soil and Water...... and recreational purposes. We also checked for the possible synergistic effects of changes in climate and land use on water flow and nutrient exports from the catchment. Simulations showed a noticeable impact of climate change in the river flow regime and consequently the water level of the limno...... the worst-case combined scenario compared to the sum of individual scenarios. Our model framework may help water managers to assess and manage how these multiple environmental stressors interact and ultimately affect aquatic ecosystems. (C) 2013 Elsevier B.V. All rights reserved....
Robinson, A.; Hernes, P.; Montanez, I.; Eustis, B.
litters studied. In all cases, using lignin source parameters of sorbed material in endmember models would result in significant error without considering sorption. Ac:al ratios of supernatants increased even more suggesting that these are not reliable indicators of diagenetic state in riverine DOM. Λ8 values, in this case, are used to indicate preferential uptake of lignin relative to bulk carbon by different soils. Comparisons between leachate and supernatant after sorption are used to trace evolution of lignin phenolic and DOM compositions as a function of their interactions with soils. For example, sequoia supernatant Λ8 values were consistently lower than that of leachates, indicating preferential uptake of lignin relative to bulk carbon by soils and thus enrichment of DOM in non-lignin components. While some fractionation effects are consistent across all litter and soil types, modeling fractionation factors for accurate lignin biomarker interpretation will require site-specific information. Leaching and sorption will alter significantly the original plant geochemical signal in terms of source and diagenetic information. Considering the importance of soils as OM sources to rivers, these data will be invaluable toward modeling dissolved OM transformations and biomarker compositional variability in sediments. We demonstrate that careful consideration of catchment properties including vegetation type, soils, and hydrology is necessary to fully access their impact on dissolved and particulate OM compositions and fluxes at the catchment scale.
S. N. Gosling
with climate change are represented similarly by both hydrological models, although for some catchments the monthly timing of high and low flows differs. This implies that for studies that seek to quantify and assess the role of climate model uncertainty on catchment-scale runoff, it may be equally as feasible to apply a GHM as it is to apply a CHM, especially when climate modelling uncertainty across the range of available GCMs is as large as it currently is. Whilst the GHM is able to represent the broad climate change signal that is represented by the CHMs, we find however, that for some catchments there are differences between GHMs and CHMs in mean annual runoff due to differences in potential evapotranspiration estimation methods, in the representation of the seasonality of runoff, and in the magnitude of changes in extreme (Q5, Q95 monthly runoff, all of which have implications for future water management issues.
van Breda, Phelia; De Clercq, Willem; Vlok, Pieter; Querner, Erik
responsibilities and inadequate procedures of implementing objectives. Planning for development in South Africa needs to take various factors into account. Economic and green economic growth is pursued, while social imbalances are addressed and the environment is protected against unreasonable exploitation. The term Sustainable Development is a neutral concept in the vision of many of the regulating authorities; however, the implementation of sustainability is difficult. This study considers an approach which aligns activities in a specified region to the vision and objectives of the applicable regulatory authorities, as an alternative to achieving objectives strictly through enforcing regulations. It was determined whether objectives of development planning were realistic in terms of water availability. It was established that the position of a farm in the landscape is a determining factor of the impact it has on the catchment area's water supply. For this purpose, hydrological modelling (SWAT and SIMGRO) was done for the Letaba catchment of the Limpopo Province, on two scales to also accommodate small-scale farming communities more accurately. Parallel to the modelling, the National Development Plan (NDP), the National Framework for Sustainable Development (NFSD), the Integrated Sustainable Rural Development Strategy (ISRDS) and the principles of Water Allocation Reform (WAR) were regarded. For regional categorisation, the relevant municipal Integrated Development Plan (IDP), Spatial Development Framework (SDF), Local Economic Development (LED) plan and the applicable Catchment Management Strategy (CMS) were considered. The developed Integrated Evaluation Model combined all the visions and objectives of the mentioned strategic documents to specifically assess the contribution a small-scale farm makes. The evaluation results provided insight into the alignment of activities to the ideals of a region and can be useful when formulating actions to reach a common vision. Small
Poulsen, Jane Bang; Sebok, Eva; Duque, Carlos;
Detecting, quantifying and understanding groundwater discharge to streams are crucial for the assessment of water, nutrient and contaminant exchange at the groundwater–surface water interface. In lowland agricultural catchments with significant groundwater discharge this is of particular importance...... because of the risk of excess leaching of nutrients to streams. Here we aim to combine hydraulic and tracer methods from point-to-catchment scale to assess the temporal and spatial variability of groundwater discharge in a lowland, groundwater gaining stream in Denmark. At the point-scale, groundwater...... fluxes to the stream were quantified based on vertical streambed temperature profiles (VTPs). At the reach scale (0.15–2 km), the spatial distribution of zones of focused groundwater discharge was investigated by the use of distributed temperature sensing (DTS). Groundwater discharge to the stream...
Grayson, Richard; Kay, Paul; Foulger, Miles
Diffuse pollution poses a threat to water quality and results in the need for treatment for potable water supplies which can prove costly. Within the Yorkshire region, UK, nitrates, pesticides and water colour present particular treatment problems. Catchment management techniques offer an alternative to 'end of pipe' solutions and allow resources to be targeted to the most polluting areas. This project has attempted to identify such areas using GIS based modelling approaches in catchments where water quality data were available. As no model exists to predict water colour a model was created using an MCE method which is capable of predicting colour concentrations at the catchment scale. CatchIS was used to predict pesticide and nitrate N concentrations and was found to be generally capable of reliably predicting nitrate N loads at the catchment scale. The pesticides results did not match the historic data possibly due to problems with the historic pesticide data and temporal and spatially variability in pesticide usage. The use of these models can be extended to predict water quality problems in catchments where water quality data are unavailable and highlight areas of concern. PMID:19029721
Full Text Available Topographic index-based hydrological models have gained wide use to describe the hydrological control on the triggering of rainfall-induced shallow landslides at the catchment scale. A common assumption in these models is that a spatially continuous water table occurs simultaneously at any point across the catchment. However, during a rainfall event isolated patches of subsurface saturation form above an impeding layer and hydrological connectivity of these patches is a necessary condition for lateral flow initiation at a point on the hillslope.
Here, a new hydrological model is presented, which allows to account for the concept of hydrological connectivity while keeping the simplicity of the topographic index approach. A dynamic topographic index is used to describe the transient lateral flow that is established at a hillslope element when the rainfall amount exceeds a threshold value allowing for (a development of a perched water table above an impeding layer, (b hydrological connectivity between the hillslope element and its own upslope contributing area. A spatially variable soil depth is the main control of hydrological connectivity in the model. The hydrological model is coupled with the infinite slope stability model, and with a scaling model for the rainfall frequency-duration relationship to determine the return period of the critical rainfall needed to cause instability on three catchments located in the Italian Alps. The results show the good ability of our model in predicting observed shallow landslides. The model is finally used to determine local rainfall intensity-duration thresholds that may lead to shallow landslide initiation.
Full Text Available The common approach to quantifying the precipitation forecast uncertainty is ensemble simulations where a numerical weather prediction (NWP model is run for a number of cases with slightly different initial conditions. In practice, the spread of ensemble members in terms of flood discharge is used as a measure of forecast uncertainty due to uncertain precipitation forecasts. This study presents the uncertainty propagation of rainfall forecast into hydrological response with catchment scale through distributed rainfall-runoff modeling based on the forecasted ensemble rainfall of NWP model. At first, forecast rainfall error based on the BIAS is compared with flood forecast error to assess the error propagation. Second, the variability of flood forecast uncertainty according to catchment scale is discussed using ensemble spread. Then we also assess the flood forecast uncertainty with catchment scale using an estimation regression equation between ensemble rainfall BIAS and discharge BIAS. Finally, the flood forecast uncertainty with RMSE using specific discharge in catchment scale is discussed. Our study is carried out and verified using the largest flood event by typhoon “Talas” of 2011 over the 33 subcatchments of Shingu river basin (2,360 km2, which is located in the Kii Peninsula, Japan.
Zheng, D.; Velde, van der R.; Su, Z.; Wen, J.; Wang, X.; Booij, M.J.; Hoekstra, A.Y.; Lv, S.; Ek, M.B.
Noah model physics options validated for the source region of the Yellow River (SRYR) are applied to investigate their ability in reproducing runoff at the catchment scale. Three sets of augmentations are implemented affecting descriptions of (i) turbulent and soil heat transport (Noah-H), (ii) soil
Full Text Available Recent work suggests that a coupled effective energy and mass transfer (EEMT term, which includes the energy associated with effective precipitation and primary production, may serve as a robust prediction parameter of critical zone structure and function. However, the models used to estimate EEMT have been solely based on long-term climatological data with little validation using direct empirical measures of energy, water, and carbon balances. Here we compare catchment-scale EEMT estimates generated using two distinct approaches: (1 EEMT modeled using the established methodology based on estimates of monthly effective precipitation and net primary production derived from climatological data, and (2 empirical catchment-scale EEMT estimated using data from 86 catchments of the Model Parameter Estimation Experiment (MOPEX and MOD17A3 annual net primary production (NPP product derived from Moderate Resolution Imaging Spectroradiometer (MODIS. Results indicated positive and significant linear correspondence (R2 = 0.75; P −2 yr−1. Modeled EEMT values were consistently greater than empirical measures of EEMT. Empirical catchment estimates of the energy associated with effective precipitation (EPPT were calculated using a mass balance approach that accounts for water losses to quick surface runoff not accounted for in the climatologically modeled EPPT. Similarly, local controls on primary production such as solar radiation and nutrient limitation were not explicitly included in the climatologically based estimates of energy associated with primary production (EBIO, whereas these were captured in the remotely sensed MODIS NPP data. These differences likely explain the greater estimate of modeled EEMT relative to the empirical measures. There was significant positive correlation between catchment aridity and the fraction of EEMT partitioned into EBIO (FBIO, with an increase in FBIO as a fraction of the total as aridity increases and percentage of
Ghafoor, A; Jarvis, N J; Thierfelder, T; Stenström, J
Degradation of pesticides in soils is both spatially variable and also one of the most sensitive factors determining losses to surface water and groundwater. To date, no general guidance is available on suitable approaches for dealing with spatial variation in pesticide degradation in catchment or regional scale modeling applications. The purpose of the study was therefore to study the influence of various soil physical, chemical and microbiological characteristics on pesticide persistence in the contrasting cultivated soils found in a small (13 km(2)) agricultural catchment in Sweden and to develop and test a simple model approach that could support catchment scale modeling. Persistence of bentazone, glyphosate and isoproturon was investigated in laboratory incubation experiments. Degradation rate constants were highly variable with coefficients of variation ranging between 42 and 64% for the three herbicides. Multiple linear regression analysis and Mallows Cp statistic were employed to select the best set of independent parameters accounting for the variation in degradation. Soil pH and the proportion of active microorganisms (r) together explained 69% of the variation in the bentazone degradation rate constant; the Freundlich sorption co-efficient (K(f)) and soil laccase activity together explained 88% of the variation in degradation rate of glyphosate, while soil pH was a significant predictor (pvariables made clear interpretations of the statistical analysis difficult. Multiplicative models based on two predictors chosen 'a priori', one accounting for microbial activity (e.g. microbial respiration, laccase activity or the surrogate variable soil organic carbon, SOC) and one accounting for the effects of sorption on bioavailability, showed promise to support predictions of degradation for large-scale modeling applications, explaining up to 50% of the variation in herbicide persistence. PMID:21353292
Srivastava, Prashant K.; Han, Dawei; Rico Ramirez, Miguel A.; Islam, Tanvir
Soil moisture is one of the important variables in hydrological modelling, which is now possible to be measured with remote sensing. This study is an attempt to evaluate the Soil Moisture and Ocean Salinity (SMOS) satellite derived soil moisture for hydrological applications at a catchment scale. The Soil Moisture Deficit (SMD) derived from a Probability Distribution Model is used as a benchmark for all comparisons. Three approaches are used for the evaluation of SMOS soil moisture. The first approach is based on ROSETTA pedotransfer functions (PTFs), while second and the third are based on linear/non-linear and seasonal algorithms particularly for growing and non-growing seasons respectively. The field capacity and permanent wilting point estimated from the simulated Water Retention Curve (WRC) through ROSETTA are used for the transformation of SMOS data into SMD. The growing seasons used in this study belong to the months from March to November, while the non-growing seasons comprise of months from December to February. The highest performance is given by a combined growing and non-growing season algorithms with the Nash Sutcliffe Efficiencies (NSEs) of 0.75 and RMSE = 0.01 m3/m3 followed by the linear and non-linear algorithms (NSE = 0.40-0.42; RMSE = 0.02 m3/m3). The worst performance is revealed by the PTFs indicating that it should be used with caution for direct coarse scale SMOS applications (NSE = -24.98 to -40.23) and need more treatments regarding the spatial and depth wise mismatch. The overall analysis reveals that SMOS soil moisture is of reasonable quality in estimating Soil Moisture Deficit at a catchment level with a local adjustment algorithm combining growing and non-growing seasons.
Velde, Y. van der; Rozemeijer, J.C.
A small fraction of the nutrients used for agriculture is transported by rivers and artificial drainage networks to downstream waters. In lakes and coastal seas such as the Baltic Sea and the Gulf of Mexico these nutrients cause large-scale algal blooms and hypoxia and thus are a major environmental
Full Text Available This paper presents the current situation in Polish water resources management. Discussed here are measures taken by the Ministry of Environment to introduce a new water law, as well as reforms of water management in Poland. The state of water resources in Poland are described, and the actions needed to improve this situation, taking into account possible climate changes and their impact on the use of water resources. Critically referred to is the introduction by the Ministry of Environment of charges for water abstraction by hydro power plants, and adverse effects for the energy and water management sectors are discussed.
Wang, Xia-Hui; Lu, Jun; Zhang, Qing-Zhong; Wang, Bo; Yao, Rui-Hua; Zhang, Hui-Yuan; Huang, Feng
Agricultural non-point source pollution is one of the major causes of water quality deterioration. Based on the analysis of the spatial discharge characteristics and intensity of major pollutants from the agricultural pollution source, the establishment of spatial management subzones for controlling agricultural non-point pollution and a design of a plan for total load control of pollutants from each subzone is an important way to improve the efficiency of control measures. In this paper the Four Lake basin in Hubei Province is adopted as the research case region and a systematic research of the control countermeasures of agricultural non-point pollution based on the catchment scale is carried out. The results shows that in the Four Lake basin, the COD, total nitrogen, total phosphorus and ammonia nitrogen load of the water environment are mainly caused by agricultural non-point pollution. These four kinds of non-point source pollutants respectively account for 67.6%, 82.2%, 84.7% and 50.9% of the total pollutant discharge amount in the basin. The analysis of the spatial discharge characteristics of non-point source pollutants in the Four Lake basin shows that the major contributor source regions of non-point source pollutant in the basin are the four counties, including Honghu, Jianli, Qianjiang and Shayang where the aquatic and livestock production are relatively developed. According to the spatial discharge characteristics of the pollutants and the evaluation of the discharge intensity of pollutants, the Four Lake basin is divided into three agricultural non-point pollution management subzones, which including Changhu upstream aquatic and livestock production pollution control subzone, Four-lake trunk canal rural non-point source pollution control subzone and Honghu aquatic production pollution control subzone. Specific pollution control measures are put forward for each subzone. With a comprehensive consideration of the water quality amelioration and the
Glauco Maia; Jorge Xavier da Silva; Tiago Marino
Water resources manageWith the mission of providing reliable data for water supply activities in medium and large firefighting operations, the Firefighting Water Supply Tactical Group (GTSAI) represents an important sector of the Rio de Janeiro State Fire Departmentment plan strategic support. Acting proactively, the Tactical Group prepared a Water Resources Management Plan, aiming to set up water resources for each jurisdiction of firefighters in the City of Rio de Janeiro, in order to assis...
Raeke, Julia; Lechtenfeld, Oliver J.; Oosterwoud, Marieke R.; Bornmann, Katrin; Tittel, Jörg; Reemtsma, Thorsten
Increasing concentrations of dissolved organic matter (DOM) in rivers of temperate catchments in Europe and North Amerika impose new technical challenges for drinking water production. The driving factors for this decadal increase in DOM concentration are not conclusive and changes in annual temperatures, precipitation and atmospheric deposition are intensely discussed. It is known that the majority of DOM is released by few but large hydrologic events, mobilizing DOM from riparian wetlands for export by rivers and streams. The mechanisms of this mobilization and the resulting molecular composition of the released DOM may be used to infer long-term changes in the biogeochemistry of the respective catchment. Event-based samples collected over two years from streams in three temperate catchments in the German mid-range mountains were analyzed after solid-phase extraction of DOM for their molecular composition by ultra-high resolution mass spectrometry (FT-ICR MS). Hydrologic conditions, land use and water chemistry parameters were used to complement the molecular analysis. The molecular composition of the riverine DOM was strongly dependent on the magnitude of the hydrologic events, with unsaturated, oxygen-enriched compounds being preferentially mobilized by large events. This pattern is consistent with an increase in dissolved iron and aluminum concentrations. In contrast, the relative proportions of nitrogen and sulfur bearing compounds increased with an increased agricultural land use but were less affected by the mobilization events. Co-precipitation experiments with colloidal aluminum showed that unsaturated and oxygen-rich compounds are preferentially removed from the dissolved phase. The precipitated compounds thus had similar chemical characteristics as compared to the mobilized DOM from heavy rain events. Radiocarbon analyses also indicated that this precipitated fraction of DOM was of comparably young radiocarbon age. DOM radiocarbon from field samples
Gateuille, David; Evrard, Olivier; Lefevre, Irène; Moreau-Guigon, Elodie; Alliot, fabrice; Chevreuil, Marc; Mouchel, Jean-Marie
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
Shrestha, R. R.; Bardossy, A.; Rode, M.
The diffuse nitrate pollution in rivers is driven by a complex interaction of hydrological and bio-chemical processes. Due to limited process understanding and restricted data availability, physically based approaches for the simulation of these dynamics are still associated with large uncertainties. Therefore we developed a combined deterministic - data driven approach, which consists of a spatially distributed water balance model WaSiM-ETH for the simulation of the different hydrological flow components and a fuzzy rule based model (FRBM) for the simulation of nitrate concentration in the river. Hydrological flow components are considered as dominant driving variables for the dynamic behaviour of nitrate concentrations in surface water The TOPMODEL approach is used for water balance and simulation of runoff components in the WaSiM-ETH model. The model is calibrated using an automatic parameter estimation program PEST. The simulated subsurface and surface runoff components are taken as input variables for the fuzzy rule based nitrate transport model. In addition to these runoff components, mean air temperature is included as an input variable for the consideration of seasonal variability. The FRBM consists of Mamdani type "IF- THEN" fuzzy rule system with triangular membership function in both the input and the output. 13 rule systems are used for the representation of the dynamics of the nitrate concentration in the river. The fuzzy rules are derived from a combination of expert knowledge and the input - output data using the simulated annealing optimization algorithm. The study was undertaken using 6 years of daily hydrological and nutrient time series data from the Weida catchment, which is a 100 km2 subcatchment of the Weisse Elster in the Elbe river basin, Germany. The results of the study show that the combined deterministic - fuzzy rule based model can give a good simulation of catchment scale nitrate dynamics. The WaSiM-ETH model produced a very good match
Full Text Available Rainfall-runoff models that adequately represent the real hydrological processes and that do not have to be calibrated, are needed in hydrology. Such a model would require information about the runoff processes occurring in a catchment and their spatial distribution. Therefore, the aim of this article is (1 to develop a methodology that allows the delineation of dominant runoff processes (DRP in the field and with a GIS, and (2 to illustrate how such a map can be used in rainfall-runoff modelling.
Soil properties were assessed of 44 soil profiles in two Swiss catchments. On some profiles, sprinkling experiments were performed and soil-water levels measured. With these data, the dominant runoff processes (DRP were determined using the Scherrer and Naef (2003 process decision scheme. At the same time, a simplified method was developed to make it possible to determine the DRP only on the basis of maps of the soil, topography and geology. In 67% of the soil profiles, the two methods indicated the same processes; in 24% with minor deviations.
By transforming the simplified method into a set of rules that could be introduced into a GIS, the distributions of the different DRPs in two catchments could be delineated automatically so that maps of the dominant runoff processes could be produced. These maps agreed well with manually derived maps and field observations.
Flood-runoff volumes could be quite accurately predicted on the basis of the rainfall measured and information on the water retention capacity contained in the DRP map. This illustrates the potential of the DRP maps for defining the infiltration parameters used in rainfall-runoff models.
Wansik Yu; Eiichi Nakakita; Sunmin Kim; Kosei Yamaguchi
The common approach to quantifying the precipitation forecast uncertainty is ensemble simulations where a numerical weather prediction (NWP) model is run for a number of cases with slightly different initial conditions. In practice, the spread of ensemble members in terms of flood discharge is used as a measure of forecast uncertainty due to uncertain precipitation forecasts. This study presents the uncertainty propagation of rainfall forecast into hydrological response with catchment scale t...
Lewis, C.; Xu, X.; Albertson, J.; Kiely, G.
GEOtop represents the new generation of distributed hydrological model driven by geospatial data (e.g. topography, soils, vegetation, land cover). It estimates rainfall-runoff, evapotranspiration and provides spatially distributed outputs as well as routing water and sediment flows through stream and river networks. The original version of GEOtop designed in Italy, includes a rigorous treatment of the core hydrological processes (e.g. unsaturated and saturated flow and transport, surface energy balances, and streamflow generation/routing). Recently GEOtop was extended to include treatment of shallow landslides. The GEOtop model is built on an open-source programming framework, which makes it well suited for adaptation and extension. GEOtop has been run very successfully in a number of alpine catchments (such as Brenta) but has not been used on Irish catchments before. The cell size used for the spatially distributed inputs varies from catchment to catchment. In smaller catchments (less than 2000ha) 50 by 50m cells have been used and 200 by 200 for larger catchments. Smaller cell sizes have been found to significantly increase the computational time so a larger cell size is used providing it does not significantly affect the performance of the model. Digital elevation model, drainage direction, landuse and soil type maps are the minimum spatial requirements with precipitation, radiation, temperature, atmospheric pressure and wind speed been the minimum meteorological requirements for a successful run. The soil type maps must also contain information regarding texture and hydraulic conductivity. The first trial of GEOtop in Ireland was on a small 1524 ha catchment in the south of Ireland. The catchment ranges from 50 to just over 200m, the land use is predominately agricultural grassland and it receives on average 1400mm of rain per year. Within this catchment there is a meteorological tower which provides the meteorological inputs, soil moisture is also recorded at
Full Text Available Reducing diffuse pollution is a perpetuating problem for environmental regulators. This paper will consider novel ways to regulate its impacts on the aquatic environment, with particular reference to rural landuse. It will look at the relationship between science, policy and law, and the contributions of integrated water resources management and governance at regional, national and river basin scales. Regulatory frameworks for water in the European Union will be explored, along with their implementation nationally in Scotland and at catchment scale in the Tweed river basin. It will conclude that regulation has a role to play, but that it is necessary to take a visionary holistic and integrated approach, nesting regulation within a governance framework that involves all stakeholders and takes full account of developing science and socio-economic drivers to meet environmental objectives.
Brudler, Sarah; Arnbjerg-Nielsen, Karsten; Rygaard, Martin
Copenhagen, Denmark, where extensive implementation of green infrastructure is planned to mitigate the adverse effects of climate change. This « green » scenario is compared to a traditional « grey » solution, utilizing pipes and basins. The environmental impacts, which are dominated by material production...... environments by adding green and blue elements, and they change the water balance compared to traditional, underground approaches. Additionally, different implementation and maintenance processes are required. All of these transformations affect the environmental impacts of urban storm water management (SWM......) systems, which can be quantified using Life Cycle Assessment (LCA). This study aims to define the multiple functions provided by a SWM system at sub-catchment scale, and to assess the environmental impacts arising from fulfilling these functions. The approach is tested using the Nørrebro catchment in...
Jencso, K.G.; McGlynn, B.L.; Gooseff, M.N.; Wondzell, S.M.; Bencala, K.E.; Marshall, L.A.
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.
The use of radiation and tracer techniques in investigations into soil water management in agriculture, hydrology etc. is described. These techniques include 1) neutron moisture gauges to monitor soil water content and soil water properties, 2) gamma radiation attenuation for measuring the total density of soil and soil water content, 3) beta radiation attenuation for measuring changes in the water status of crop plants and 4) radioactive and stable tracers for identifying pathways, reactions and retention times of the constituents in soils and groundwater aquifers. The number and spacing of soil observations that should be taken to represent the management unit are also considered. (U.K.)
J. B. Poulsen
Full Text Available Detecting, quantifying, and understanding groundwater discharge to streams are crucial for the assessment of water, nutrient and contaminant exchange at the surface water–groundwater interface. In lowland agricultural catchments with significant groundwater discharge this is of particular importance because of the risk of excess leaching of nutrients to streams. Here we aim to combine hydraulic and tracer methods from point to catchment scale to assess the temporal and spatial variability of groundwater discharge in a lowland, groundwater gaining stream in Denmark. At the point scale groundwater fluxes to the stream were quantified based on Vertical streambed Temperature Profiles (VTP. At the reach scale (0.15–2 km the spatial distribution of zones of focused groundwater discharge was investigated by the use of Distributed Temperature Sensing (DTS. Groundwater discharge to the stream was quantified using differential gauging with an Acoustic Doppler Current Profiler (ADCP. At the catchment scale (26–114 km2 runoff sources during main rain events were investigated by hydrograph separations based on Electrical Conductivity (EC and stable isotopes 2H / 1H. Clear differences in runoff sources between catchments were detected, ranging from approximately 65% event water for the most responsive sub-catchment and less than 10% event water for the least responsive sub-catchment. This shows a large variability in groundwater discharge to the stream, despite the similar lowland characteristics of sub-catchments, indicating the usefulness of environmental tracers for obtaining information about integrated catchment functioning during events. There were also clear spatial patterns of focused groundwater discharge detected by the DTS and ADCP measurements at the reach scale suggesting high spatial variability, where a significant part of groundwater discharge was concentrated in few zones indicating the possibility of concentrated nutrient or pollutant
Loinaz, Maria C.; Gross, Dayna; Unnasch, Robert; Butts, Michael; Bauer-Gottwein, Peter
A number of anthropogenic stressors, including land use change and intensive water use, have caused stream habitat deterioration in arid and semiarid climates throughout the western U.S. These often contribute to high stream temperatures, a widespread water quality problem. Stream temperature is an important indicator of stream ecosystem health and is affected by catchment-scale climate and hydrological processes, morphology, and riparian vegetation. To properly manage affected systems and achieve ecosystem sustainability, it is important to understand the relative impact of these factors. In this study, we predict relative impacts of different stressors using an integrated catchment-scale ecohydrological model that simulates hydrological processes, stream temperature, and fish growth. This type of model offers a suitable measure of ecosystem services because it provides information about the reproductive capability of fish under different conditions. We applied the model to Silver Creek, Idaho, a stream highly valued for its world-renowned trout fishery. The simulations indicated that intensive water use by agriculture and climate change are both major contributors to habitat degradation in the study area. Agricultural practices that increase water use efficiency and mitigate drainage runoff are feasible and can have positive impacts on the ecosystem. All of the mitigation strategies simulated reduced stream temperatures to varying degrees; however, not all resulted in increases in fish growth. The results indicate that temperature dynamics, rather than point statistics, determine optimal growth conditions for fish. Temperature dynamics are influenced by surface water-groundwater interactions. Combined restoration strategies that can achieve ecosystem stability under climate change should be further explored.
Candela, Angela; Viviani, Gaspare
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
Gateuille, D.; Evrard, O.; Lefevre, I.; Moreau-Guigon, E.; Alliot, F.; Chevreuil, M.; Mouchel, J.-M.
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
US Fish and Wildlife Service, Department of the Interior — The Bear River Migratory Bird Refuge Water Management Plan has been developed to meet the station objectives set forth in the Master Plan. The purpose of this plan...
US Fish and Wildlife Service, Department of the Interior — The Clarence Cannon National Wildlife Refuge Water Management Plan has been developed to meet the station objectives. The purpose of this plan is to establish a...
A data-based approach is presented to analyse the response behaviour of hydrological models at the catchment scale. The approach starts with a number of sequential time series processing steps, applied to available rainfall, ETo and river flow observation series. These include separation of the high frequency (e.g., hourly, daily) river flow series into subflows, split of the series in nearly independent quick and slow flow hydrograph periods, and the extraction of nearly independent peak and low flows. Quick-, inter- and slow-subflow recession behaviour, sub-responses to rainfall and soil water storage are derived from the time series data. This data-based information on the catchment response behaviour can be applied on the basis of: - Model-structure identification and case-specific construction of lumped conceptual models for gauged catchments; or diagnostic evaluation of existing model structures; - Intercomparison of runoff responses for gauged catchments in a river basin, in order to identify similarity or significant differences between stations or between time periods, and relate these differences to spatial differences or temporal changes in catchment characteristics; - (based on the evaluation of the temporal changes in previous point:) Detection of temporal changes/trends and identification of its causes: climate trends, or land use changes; - Identification of asymptotic properties of the rainfall-runoff behaviour towards extreme peak or low flow conditions (for a given catchment) or towards extreme catchment conditions (for regionalization, ungauged basin prediction purposes); hence evaluating the performance of the model in making extrapolations beyond the range of available stations' data; - (based on the evaluation in previous point:) Evaluation of the usefulness of the model for making extrapolations to more extreme climate conditions projected by for instance climate models. Examples are provided for river basins in Belgium, Ethiopia, Kenya
Turner, Kate; Worrall, Fred
Only 3% of the earths land surface is covered by peatland yet boreal and subarctic peatlands store approximately 15-30% of the World's soil carbon as peat (Limpens et al. 2008). In comparison British bogs store carbon equivalent to 20 years worth of national emissions. The loss of carbon from these areas in the form of dissolved organic carbon (DOC) is increasing and it is expected to have grown by up to 40% by 2018. Extensive drainage of UK peatlands has been associated with dehydration of the peat, an increase in water colour and a loss of carbon storage. It has been considered that the blocking of these drainage channels represents a means of peat restoration and a way of reducing DOC loss. This study aims to assess the effectiveness of this drain blocking at both an individual drain scale and at a larger catchment scale. Gibson et al. (2009) considered the effects of blocking at a solely individual drain scale finding that a 20% drop in DOC export was recorded post blocking however this decrease was due to a reduction in water yield rather than a reduction in DOC concentration with the concentration record showing no significant reduction. The effect of external parameters become more pronounced as the DOC record is examined at larger scales. The catchment is an open system and water chemistry will be influence by mixing with water from other sources. Also it is likely that at some point the drains will cut across slope leading to the flow of any highly coloured water down slope, bypassing the blockages, and entering the surface waters downstream. Degradation of DOC will occur naturally downstream due to the effects of light and microbial activity. There is, consequently, a need to examine the wider effects of drain blocking at a catchment scale to ensure that what is observed for one drain transfers to the whole catchment. A series of blocked and unblocked catchments were studied in Upper Teesdale, Northern England. Drain water samples were taken at least
Jarmain, C.; Everson, C. S.; Gush, M. B.; Clulow, A. D.
The contribution of hydrological research in South Africa in quantifying green water flows for improved Integrated Land and Water Resources Management is reviewed. Green water refers to water losses from land surfaces through transpiration (seen as a productive use) and evaporation from bare soil (seen as a non-productive use). In contrast, blue water flows refer to streamflow (surface water) and groundwater / aquifer recharge. Over the past 20 years, a number of methods have been used to quantify the green water and blue water flows. These include micrometeorological techniques (e.g. Bowen ratio energy balance, eddy covariance, surface renewal, scintillometry, lysimetry), field scale models (e.g. SWB, SWAP), catchment scale hydrological models (e.g. ACRU, SWAT) and more recently remote sensing based models (e.g. SEBAL, SEBS). The National Water Act of South Africa of 1998 requires that water resources are managed, protected and used (developed, conserved and controlled) in an equitable way which is beneficial to the public. The quantification of green water flows in catchments under different land uses has been pivotal in (a) regulating streamflow reduction activities (e.g. forestry) and the management of alien invasive plants, (b) protecting riparian and wetland areas through the provision of an ecological reserve, (c) assessing and improving the water use efficiency of irrigated pastures, fruit tree orchards and vineyards, (d) quantifying the potential impact of future land uses like bio-fuels (e.g. Jatropha) on water resources, (e) quantifying water losses from open water bodies, and (f) investigating "biological” mitigation measures to reduce the impact of polluted water resources as a result of various industries (e.g. mining). This paper therefore captures the evolution of measurement techniques applied across South Africa, the impact these results have had on water use and water use efficiency and the extent to which it supported the National Water Act of
Cristea, N. C.; Burges, S. J.
Evapotranspiration (ET) is a key water budget term that is rarely evaluated in hydrologic modeling due to the scarcity of observed actual ET fluxes. However, the ET process representation within a hydrologic model is important as it affects the simulated hydrologic response. Here we illustrate how different ET representations affect both the hydrograph and the soil moisture states within MODHMS, a Richards' equation based distributed hydrologic model at the catchment scale. MODHMS, a MODFLOW based model, has a flexible modular structure that allowed testing of 4 different base case ET scenarios: two MODFLOW ET representations (linear and piece-wise linear) and one physically based ET model in two configurations. These 4 ET sub-models were applied sequentially for the case of the well-studied 10.5 ha - Tarrawarra catchment in Australia keeping the soil parameterization constant. The hydrologic response sensitivity to each of the ET sub-models parameterization was evaluated. The ET process representation chosen for use in MODHMS is important for adequately representing soil saturation areas, lateral flow and drying of the upslope areas of the catchment as well as the outflow hydrograph.
Davenport, I. J.; Silgram, M.; Robinson, J. S.; Lamb, A.; Settle, J. J.
Remote sensing has the potential to provide information useful in improving the mod- elling of pollution transport in agricultural catchments. The realisation of this potential will depend on the availability of the raw data, the development of techniques for ex- tracting information from this data, and the assimilation of the derived information into models. Each of these aspects has been explored and assessed by this group, and this presentation will describe its findings. Two main objectives were defined in this work. Firstly, to define, quantify, and demonstrate how future spaceborne Earth Ob- servation (EO) derived information can be utilised to improve the accuracy and spatial resolution of input parameters to pollution models of nitrate (N) and phosphate (P) export at the field and catchment scale. Secondly, to quantify the impact of improved accuracy and spatial resolution of input data on model predictions of nutrient export from agricultural fields. These objectives were explored by acquiring high spatial resolution hyperspectral data and laser altimetry of two farm sites near Hereford, UK. The data were then analysed to generate information such as topography, crop type and fractional vegetation cover at different resolutions. A technique was developed to identify the soil and vegetation endmembers within high resolution hyperspectral imagery of a field, enabling an es- timation of the vegetation fraction to be extracted. The results of this technique were compared to conventional methods used with fewer spectral bands. Aerially-acquired laser altimetry was also processed to produce high resolution Digital Elevation Models of the site. Nutrient flow models were then developed to assimilate this information and predict N and P run-off. At the sub-field scale the hypothesis that higher resolution topography will make a substantial difference to contaminant transport was tested using the AGricultural Non- Point Source (AGNPS) model at 20m, 50m and 100m cell
Plesca, Ina; Kraft, Philipp; Haas, Edwin; Klatt, Steffen; Butterbach-Bahl, Klaus; Frede, Hans-Georg; Breuer, Lutz
Hydrological and biogeochemical transport through changing landscapes has been well described during the past years in literature. However, the uncertainties of combined water quality and water quantity models are still challenging, both due to a lack in process understanding as well to spatiotemporal heterogeneity of environmental conditions driving the processes. In order to reduce the uncertainty in water quality and runoff predictions at the catchment scale, a variety of different model approaches from empirical-conceptual to fully physical and process based models have been developed. In this study we present a new modelling approach for the investigation of hydrological processes and nutrient cycles, with a focus on nitrogen in a small catchment from Hessen, Germany. A hydrological model based on the model toolbox Catchment Modelling Framework (CMF) has been coupled with the process based biogeochemical model LandscapeDNDC. States, fluxes and parameters are exchanged between the models at high temporal and spatial resolution using the Python scripting language in order to obtain a 3-dimensional model application. The transport of water and nutrients through the catchment is modelled using a 3D Richards/Darcy approach for subsurface fluxes, a kinematic wave approach for surface runoff and a Penman-Monteith based calculation of evapotranspiration. Biogeochemical processes are modelled by Landscape-DNDC, including plant growth and biomass allocation, organic matter mineralisation, nitrification, denitrification and associated nitrous oxide emissions. The interactions and module connectivity between the two coupled models, as well as the model application on a 3.7 km² catchment with the runoff results and nitrogen quantification will be presented in this study.
US Fish and Wildlife Service, Department of the Interior — Ruby Lake NWR 1987 Annual Water Management Report 1988 Annual Water Management Plan. Includes 1987 weather summary, water availability forecast, summary of 1987...
Böttcher, T.; Schroll, R.
Spray-drift, drainage, erosion and runoff events are the major causes responsible for deportation of agrochemicals as micropollutants to aquatic non-target sites. These processes can lead to the contamination of nearby freshwater ecosystems with considerably high concentrations of xenobiotics. Thus, it is important to unravel the fate of these pollutants and to evaluate their ecological effects. A novel approach to address this goal was established by the development of a microcosm with multiple sampling abilities enabling quantitative assessment of organic volatilisation, mineralization, metabolization and distribution within the aquatic ecosystem. This microcosm system was designed to support modelling approaches of the catchment scale and gain insights into the fate of pesticides simulating a large scale water body. The potential of this microcosm was exemplified for Isoproturon (IPU), a phenylurea derived systemic herbicide, which is frequently found as contaminant in water samples and with the free-floating macrophyte Lemna minor as non-target species, that is common to occur in rural water bodies. During 21 days exposure time, only a small amount of 14C labeled IPU was removed from the aquatic medium. The major portion (about 5%) was accumulated by Lemna minor resulting in a BCF of 15.8. IPU-volatilisation was very low with 0.13% of the initially applied herbicide. Only a minor amount of IPU was completely metabolized, presumably by rhizosphere microorganisms and released as 14CO2. The novel experimental system allowed to quantitatively investigate the fate of IPU and showed a high reproducibility with a mean average 14C-recovery rate of 97.1
Valek, Susan E.
Energy efficiency isn't just a good idea; it's a necessity, both for cost reasons and to meet federal regulatory requirements. First, rising energy unit costs continue to erode NASA's mission budget. NASA spent roughly $156M on facility energy in FY 2007. Although that represents less than one per cent of NASA's overall annual budget, the upward trend in energy costs concerns the agency. While NASA reduced consumption 13%, energy unit costs have risen 63%. Energy cost increases counteract the effects of energy conservation, which results in NASA buying less yet spending more. The second factor is federal energy legislation. The National Energy Conservation Policy Act, as amended by the Energy Policy Act of 2005, Executive Order (EO) 13423 (January, 2007), and the Energy Independence and Security Act (December, 2007), mandates energy/water conservation goals for all federal agencies, including NASA. There are also reporting requirements associated with this legislation. The Energy/Water Management Task was created to support NASA Headquarters Environmental Management Division (HO EMD) in meeting these requirements. With assistance from TEERM, HQ EMD compiled and submitted the NASA Annual Report to the Department of Energy FY 2007. The report contains information on how NASA is meeting federally mandated energy and water management goals. TEERM monitored input for timeliness, errors, and conformity to the new energy/water reporting guidelines and helped compile the information into the final report. TEERM also assists NASA Energy/Water Management with proposal and award calls, updates to the energy/water management database, and facilitating communication within the energy/water management community. TEERM is also supporting NASA and the Interagency Working Group (IWG) on Hydrogen and Fuel Cells. Established shortly after the President announced the Hydrogen Fuel Initiative in 2003, this IWG serves as the mechanism for collaboration among the Federal agencies
Danapour, Mehrdis; Stisen, Simon; Lajer Højberg, Anker
Transient coupled surface-subsurface models are usually complex and contain a large amount of spatio-temporal information. In the traditional calibration approach, model parameters are adjusted against only few spatially aggregated observations of discharge or individual point observations of groundwater head. However, this approach doesn't enable an assessment of spatially explicit predictive model capabilities at the intermediate scale relevant for many applications. The overall objectives of this project is to develop a new model calibration and evaluation framework by combining distributed model parameterization and regularization with new types of objective functions focusing on optimizing spatial patterns rather than individual points or catchment scale features. Inclusion of detailed observed spatial patterns of hydraulic head gradients or relevant information obtained from remote sensing data in the calibration process could allow for a better representation of spatial variability of hydraulic properties. Pilot Points as an alternative to classical parameterization approaches, introduce great flexibility when calibrating heterogeneous systems without neglecting expert knowledge (Doherty, 2003). A highly parameterized optimization of complex distributed hydrological models at catchment scale is challenging due to the computational burden that comes with it. In this study the physically-based coupled surface-subsurface model MIKE SHE is calibrated for the 8,500 km2 area of central Jylland (Denmark) that is characterized by heterogeneous geology and considerable groundwater flow across topographical catchment boundaries. The calibration of the distributed conductivity fields is carried out with a pilot point-based approach, implemented using the PEST parameter estimation tool. To reduce the high number of calibration parameters, PEST's advanced singular value decomposition combined with regularization was utilized and a reduction of the model's complexity was
Mikkelsen, Peter Steen; Viklander, M.; Linde, Jens Jørgen;
Best Management Practices (BMPs) for control of stormwater runoff include structural elemts (structural BMPs) that can be applied on the local scale (e.g. infiltration), the drainage catchment scale (e.g. ponds and treatment, or wetlands) and the receiving water scale (e.g. retrofitting of river ...... review of recent experiences with selected stormwater BMPs in Denmark and Sweden is presented and discussed with respect to the current issues related to legislation and the forces driving future development in stormwater management....
K. William Easter; Robert HEARNE
Because of its importance and the perceived inability of private sector sources to meet water demands, many countries have depended on the public sector to provide water services for their populations. Yet this has resulted in many inefficient public water projects and in inadequate supplies of good quality and reliable water. Decentralization of water management, including the use of water markets, cannot solve all of the water problems, but it can improve the efficiency of water allocation....
Full Text Available Water resources manageWith the mission of providing reliable data for water supply activities in medium and large firefighting operations, the Firefighting Water Supply Tactical Group (GTSAI represents an important sector of the Rio de Janeiro State Fire Departmentment plan strategic support. Acting proactively, the Tactical Group prepared a Water Resources Management Plan, aiming to set up water resources for each jurisdiction of firefighters in the City of Rio de Janeiro, in order to assist the Fire Department in its missions. This goal was reached, and in association with LAGEOP (Geoprocessing Laboratory, UFRJ, the Tactical Group started using GIS techniques. The plan provides for the register of existing operational structures within each group (troops, vehicles and special equipment, along with knowledge about the nature and operating conditions of fire hydrants, as well as a detailed survey of areas considered to be "critical". The survey helps to support actions related to environmental disasters involved in the aforementioned critical areas (hospital, churches, schools, and chemical industries, among others. The Caju neighborhood, in Rio de Janeiro, was defined as initial application area, and was the first jurisdiction to have the system implemented, followed by Copacabana, Leblon, Lagoa, and Catete districts.
The implementation of a GIS support system for the management of water resources at a catchment scale is presented. This system is based upon the hidroSIG java software, which was developed within the Atlas Hidrologico de Colombia project. In the GIS database was included all the information required by the environmental authorities in charge of the water resources management, offering the possibility of displaying, consulting and evaluating different scenarios that could help to make decisions upon the assignation and use of the resource. As a first application of the GIS, a 35 km2 river basin located in Rionegro Plateau was used. The applied methodology was developed in the following stages: gathering of the available information, processing of the digital topography, study of the dynamics of the climate in the zone, evaluation of the water availability, and evaluation of the demand and water balance. The results obtained show the importance of having continuous and articulated spatial information in a GIS, so permanent update of the information is allowed. It is concluded that the implemented GIS constitutes a valuable tool for planning and management of the hydric resource within a hydrographic basin
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...
Quinn, P. F.; Wilkinson, M. E.; Burke, S.; O'Donnell, G. M.; Jonczyk, J.; Barber, N.; Nicholson, A.
Recent catchment initiatives have highlighted the need for new holistic approaches to sustainable water management. Catchment Systems Engineering seeks to describe catchment the function (or role) as the principal driver for evaluating how it should be managed in the future. Catchment Systems Engineering does not seek to re-establish a natural system but rather works with natural processes in order to engineer landscapes to accrue multiple benefits. The approach involves quantifying and assessing catchment change, impacts and most importantly, suggests an urgent and proactive agenda for future planning. In particular, an interventionist approach to managing hydrological flow pathways across scale is proposed. It is already accepted that future management will require a range of scientific expertise and full engagement with stakeholders. This inclusive concept under a Catchment Systems Engineering agenda forces any consortia to commit to actively changing and perturbing the catchment system and thus learn, in situ, how to manage the environment for collective benefits. The shared cost, the design, the implementation, the evaluation and any subsequent modifications should involve all relevant parties in the consortia. This joint ownership of a 'hands on' interventionist agenda to catchment change is at the core of Catchment Systems Engineering. In this paper we show a range of catchment engineering projects from the UK that have addressed multi-disciplinary approaches to flooding, pollution and ecosystem management, whilst maintaining economic food production. Examples using soft engineered features such as wetlands, ponds, woody debris dams and infiltration zones will be shown. Local scale demonstration activities, led by local champions, have proven to be an effective means of encouraging wider uptake. Evidence that impacts can be achieved at local catchment scale will be introduced. Catchment Systems Engineering is a concept that relies on all relevant parties
In this paper are presented a general description of water resource systems, a systematisation of the management tasks and the approaches for solution, including a review of methods used for solution of water management tasks and the fundamental postulates in the management. The management of water resources is a synonym for the management actions applied to water resource systems. It is a general term that unites planning and exploitation of the systems. The modern planning assumes separating the water racecourse part from the hydro technical part of the project. The water resource study is concerned with the solution for the resource problem. This means the parameters of the system are determined in parallel with the definition of the water utilisation regime. The hydro-technical part of the project is the design of structures necessary for the water resource solution. (Original)
Palla, Anna; Gnecco, Ilaria
In this paper, the implementation of Low Impact Development systems (LIDs) as source control solutions that contribute to restore the critical components of natural flow regimes, is analyzed at the urban catchment scale. The hydrologic response of a small urban catchment is investigated under different land use conversion scenarios including the installation of green roofs and permeable pavements. The modeling is undertaken using the EPA SWMM; the "do nothing" scenario is calibrated and validated based on field measurements while the LID control modules are calibrated and validated based on laboratory test measurements. The simulations are carried out by using as input the synthetic hyetographs derived for three different return periods (T = 2, 5 and 10 years). Modeling results confirm the effectiveness of LID solutions even for the design storm event (T = 10 years): in particular a minimum land use conversion area, corresponding to the Effective Impervious Area reduction of 5%, is required to obtain noticeable hydrologic benefits. The conversion scenario response is analyzed by using the peak flow reduction, the volume reduction and the hydrograph delay as hydrologic performance indexes. Findings of the present research show that the hydrologic performance linearly increases with increasing the EIA reduction percentages: at 36% EIA reduction (corresponding to the whole conversion of rooftops and parking lot areas), the peak and volume reductions rise till 0.45 and 0.23 respectively while the hydrograph delay increases till 0.19.
Basch, G.; Kassam, A.; Friedrich, T; Santos, F. L.; Gubiani, P.I.; Calegari, A.; J. M. Reichert; dos Santos, D.R.
Soil quality and its management must be considered as key elements for an effective management of water resources, given that the hydrological cycle and land management are intimately linked (Bossio et al. 2007). Soil degradation has been described by Bossio et al. (2010) as the starting point of a negative cycle of soil-water relationships, creating a positive, self-accelerating feedback loop with important negative impacts on water cycling and water productivity. Therefore, sustainable soil...
O. Maguire, Rory; Rubæk, Gitte Holton; E. Haggard, Brian;
average surplus of 11 kg P ha-1 remains. Northern Ireland is also trying to move toward mass balance, but decreases in inorganic P fertilizer use have been undermined by an increase in the use of feed concentrates. In the Chesapeake Bay watershed, which covers several states in the USA, a variety of best...... management practices are starting to have an effect on P losses from agriculture, but water quality has only improved slightly. Impairment to the supply of drinking water to the City of Tulsa Oklahoma led to a lawsuit that has greatly affected the management of poultry litter in the supplying watershed. This...
Wortmann, Michel; Bolch, Tobias; Krysanova, Valentina; Buda, Su
Glacierised river catchments have been shown to be highly sensitive to climate change, while large populations depend on the water resources originating from them. Hydrological models are used to aid water resource management, yet their treatment of glacier processes is either rudimentary in large applications or linked to fully distributed glacier models that prevent larger model domains. Also, data scarcity in mountainous catchments has hampered the implementation of physically based approa...
Thomas K. Alexandridis; Ines Cherif; George Bilas; Waldenio G. Almeida; Isnaeni M. Hartanto; Schalk Jan van Andel; Antonio Araujo
Despite playing a critical role in the division of precipitation between runoff and infiltration, soil moisture (SM) is difficult to estimate at the catchment scale and at frequent time steps, as is required by many hydrological, erosion and flood simulation models. In this work, an integrated methodology is described to estimate SM at the root zone, based on the remotely-sensed evaporative fraction (Λ) and ancillary information on soil and meteorology. A time series of Terra MODIS sat...
Schmengler, A. C.; Vlek, P. L. G.
Modelling soil erosion requires a holistic understanding of the sediment dynamics in a complex environment. As most erosion models are scale-dependent and their parameterization is spatially limited, their application often requires special care, particularly in data-scarce environments. This study presents a hierarchical approach to overcome the limitations of a single model by using various quantitative methods and soil erosion models to cope with the issues of scale. At hillslope scale, the physically-based Water Erosion Prediction Project (WEPP)-model is used to simulate soil loss and deposition processes. Model simulations of soil loss vary between 5 to 50 t ha-1 yr-1 dependent on the spatial location on the hillslope and have only limited correspondence with the results of the 137Cs technique. These differences in absolute soil loss values could be either due to internal shortcomings of each approach or to external scale-related uncertainties. Pedo-geomorphological soil investigations along a catena confirm that estimations by the 137Cs technique are more appropriate in reflecting both the spatial extent and magnitude of soil erosion at hillslope scale. In order to account for sediment dynamics at a larger scale, the spatially-distributed WaTEM/SEDEM model is used to simulate soil erosion at catchment scale and to predict sediment delivery rates into a small water reservoir. Predicted sediment yield rates are compared with results gained from a bathymetric survey and sediment core analysis. Results show that specific sediment rates of 0.6 t ha-1 yr-1 by the model are in close agreement with observed sediment yield calculated from stratigraphical changes and downcore variations in 137Cs concentrations. Sediment erosion rates averaged over the entire catchment of 1 to 2 t ha-1 yr-1 are significantly lower than results obtained at hillslope scale confirming an inverse correlation between the magnitude of erosion rates and the spatial scale of the model. The
Bloodworth, J W; Holman, I P; Burgess, P J; Gillman, S; Frogbrook, Z; Brown, P
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
Mitigating agricultural diffuse pollution and greenhouse gas emissions is a complicated task due to tempo-spatial lags between the field practices and the watershed responses. Spatially-distributed modeling is essential to the implementation of cost-effective and best management practices (BMPs) to optimize land uses and nutrient applications as well as to project the impact of climate change on the watershed service functions. CNMM (the Catchment Nutrients Management Model) is a 3D spatially-distributed, grid-based and process-oriented biophysical model comprehensively developed to simulate energy balance, hydrology, plant/crop growth, biogeochemistry of life elements (e.g., C, N and P), waste treatment, waterway vegetation/purification, stream water quality and land management in agricultural watersheds as affected by land utilization strategies such as BMPs and by climate change. The CNMM is driven by a number of spatially-distributed data such as weather, topography (including DEM and shading), stream network, stream water, soil, vegetation and land management (including waste treatments), and runs at an hourly time step. It represents a catchment as a matrix of square uniformly-sized cells, where each cell is defined as a homogeneous hydrological response unit with all the hydrologically-significant parameters the same but varied at soil depths in fine intervals. Therefore, spatial variability is represented by allowing parameters to vary horizontally and vertically in space. A four-direction flux routing algorithm is applied to route water and nutrients across soils of cells governed by the gradients of either water head or elevation. A linear channel reservoir scheme is deployed to route water and nutrients in stream networks. The model is capable of computing CO2, CH4, NH3, NO, N2O and N2 emissions from soils and stream waters. The CNMM can serve as an idea modelling tool to investigate the overwhelming critical zone research at various catchment scales.
The study reviews Niger's water resources, and planning process, through its short- and medium-term water investment program, and priorities in the water supply, and sanitation sector. Critical challenges are examined for improving its complex water resources management to support economic growth, given its landlocked situation, with diffuse, and mostly rural population, and immense, untap...
Mallawaarachchi, Thilak; Mazur, Kasia; Lawson, Kenton
We develop a catchment scale modeling framework to identify cost-effective strategies for joint onsite abatement and offsite mitigation of land-based pollution from agricultural activities that pose a risk to water quality in the Great Barrier Reef (GBR). An illustrative example of the Barron catchment in north Queensland is used to demonstrate an approach to specify social planner's problem for non-point source pollution management as a cost minimisation model to meet a specified reduction i...
Yang, Chih; Wang, Mu-Hao
This volume provides in-depth coverage of such topics as multi-reservoir system operation theory and practice, management of aquifer systems connected to streams using semi-analytical models, one-dimensional model of water quality and aquatic ecosystem-ecotoxicology in river systems, environmental and health impacts of hydraulic fracturing and shale gas, bioaugmentation for water resources protection, wastewater renovation by flotation for water pollution control, determination of receiving water’s reaeration coefficient in the presence of salinity for water quality management, sensitivity analysis for stream water quality management, river ice process, and computer-aided mathematical modeling of water properties. This critical volume will serve as a valuable reference work for advanced undergraduate and graduate students, designers of water resources systems, and scientists and researchers. The goals of the Handbook of Environmental Engineering series are: (1) to cover entire environmental fields, includin...
Khan, S.; Hong, Y.; Vieux, B.; Crawford, K.
Evapotranspiration (ET) is a major component of the hydrologic cycle and links diverse disciplines such as those involved in water resource planning with agriculture, ecology and climate science. Oklahoma typically hosts irrigated agriculture, rainfed wetlands, and riparian vegetation. As demand for water increases, water managers need to know how much water is actually consumed. For the past decades, the primary method for estimating ET relies on site-based weather station measurements, which are inadequate to monitor the spatial variability of ET over large regions and focus on potential rather than actual ET. With the advent of new satellite technology and comprehensive water balance and runoff models, opportunities exist to develop algorithms and apply remote sensing information to estimate actual ET. The main objective of this presentation is to evaluate the ability and usefulness of the remote sensing ET estimation algorithms in Oklahoma that does not require placement of in-situ monitoring/metering devices. First, a surface-energy-balance ET estimation algorithm is implemented with modification for two counties with differing climate, soil, and land surface types. Accuracy of the estimated ET is evaluated at the site scale using available Mesonet stations and an Ameriflux tower. Second, modeled actual ET from a distributed hydrologic model is compared with the remotely sensed actual ET at catchment scales on the order of several hundreds of square kilometers. Results demonstrate the feasibility of implementing real-time monitoring of actual ET estimation system for more accurate water use monitoring and, therefore, provide for better water resources management in Oklahoma.
Literature related to sustainable water management is reviewed to illustrate the relationship among water management, sustainability (sustainable development), and sustainable water management. This review begins with the explanation on the definition of sustainable water management, followed by a discussion of sustainable water management principles and practices.
Melland, A. R.; Jordan, P.; Mellander, P.; Wall, D. J.; Buckley, C.; Mechan, S.; Shortle, G.
The European Union (EU) Nitrates Directive regulations in Ireland limits the use of agricultural fertilisers to agronomic optima and aims to minimise surplus phosphorus (P) and nitrogen (N) losses to the aquatic environment. The legislated measures include limits on nutrient application according to soil P status, crop type and livestock intensity and restricts chemical and organic fertiliser spreading and ploughing to periods of the year with typically lower exposure of nutrients to runoff and leaching. These agricultural policies are being evaluated in an Agricultural Catchments Programme in six representative catchments dominated by moderate to high intensity grassland and arable enterprises across Ireland (Fealy et al., 2010). An experimental programme has been established to provide a baseline of farm nutrient management and water body quality during the early years of the measures and to provide estimates of trajectories towards (or otherwise) water quality targets. A ‘nutrient transfer continuum’ from source, through pathways, to delivery and impact in a water body receptor describes the different phases of diffuse pollution and is being used as a framework for evaluation. Compliance with Irish standards at different levels of the continuum is being evaluated and demonstrative studies are being conducted to provide evidence of linkages between source and delivery to validate conceptual models of P and N transfers in time and space in each catchment. Source compliance is being evaluated through census soil testing and a survey of nutrient management practice and farmyard infrastructure. Mobilisation and pathways of nutrient transfers do not have chemical standards except where a groundwater body acts as both a receptor and a pathway. To demonstrate these linkages, however, representative groundwater pathways are being monitored through piezometer, chemical end-member and tracer studies, and surface water pathways are being evaluated through subcatchment
Daniel P. LOUCKS; Haifeng JIA
Water is essential for life. In spite of the entire engineering infrastructure devoted to the treatment, regulation and beneficial uses of water, occasionally sufficient quantities and qualities of water become scarce. When this happens, just how do we decide how much less water to allocate to all of us and the activities we engage in to sustain and enhance our quality of life？ This paper addresses some of the complexities of answering such a question, especially as society increasingly recognizes the need to provide flow regimes that will maintain healthy aquatic and floodplain ecosystems that also impact the economic, physical and even the spiritual quality of our lives. For we depend on these ecosystems to sustain our wellbeing. We are indeed a part of our ecosystems. We depend upon on aquatic ecosystems to moderate river flow qualities and quantities, reduce the extremes of floods and droughts, reduce erosion, detoxify and decompose water- borne wastes, generate and preserve flood plain soils and renew their fertility, regulate disease carrying organisms, and to enhance recreational benefits of river systems. This question of deciding just how much water to allocate to each water user and for the maintenance of viable aquatic ecosystems, especially when there is not enough, is a complex, and largely political, issue. This issue is likely to become even more complex and political and contentious in the future as populations grow and as water quantities and their qualities become even more variable and uncertain.
The report was drawn up for the US day on water pollution prevention on 22 March 1994, as a follow-up to the 1992 Rio de Janairo conference on the environment and development, and presented to the International Water Conference in Noordwijk, the Netherlands. It gives a current overview of the foundations and structure, the development, position and points of emphasis for the german water industry. The report illustrates the extent of the success of german measures towards resolving it's water pollution problems, in particular the reduction of contamination. It clarifies the great challenges facing the german water industry in the Nineties, and hence illustrates more long-term goals - which will only be achieved through greater international cooperation. (orig./HP)
River systems and the quantity and quality of water depend on the catchment, its structure and land use. In central Europe especially land is a scarce resource. This causes conflicts between different types of land use, but also with the interests of flood protection, nature conservation and the protection of water resources and water bodies in the flood plain and on a catchment scale. ILUP - Integrated Land Use Planning and River Basin Management was a project, funded by the European Union, to address the problems of conflicting interests within a catchment. It addressed the problems of conflicting land use from a hydrological perspective and with regard to the resulting problems of water management. Two test river basins, Vils and Rott, both with a catchment size of about 1000 square kilometres, were considered for the German part of the project. Objective of the project was to identify means of managing land use with regard to water management objectives and adapt planning strategies and methodologies of water management authorities to the new needs of catchment management and planning. Catchment models were derived to simulate hydrological processes, assess the safety of dams and improve the control strategy of detention reservoirs with regard to land use in the lower system. Hydrodynamic models provided the basis to assess flood prone areas, evaluate flood protection measures and analyze the impacts of river training and discharge on morphology. Erosion and transport models were used to assess the impacts of land use on water quality. Maps were compiled from model results to provide a basis for decision making. In test areas new ways of planning and implementation of measures were tested. As a result of model scenarios in combination with the socio economic situation in the catchment new methods of land management and land use management were derived and implemented in model areas. The results of the project show that new ways of managing land use in river
US Fish and Wildlife Service, Department of the Interior — The Upper Mississippi River National Wildlife and Fish Refuge - Savanna District Water Management Plan has been developed to meet the station objectives set forth...
US Fish and Wildlife Service, Department of the Interior — The Union Slough National Wildlife Refuge Water Management Plan has been developed to meet the station objectives set forth in the Master Plan. The purpose of this...
The buildup of scale and corrosion is the most costly maintenance problem in cooling tower operation. Jet Propulsion Laboratory successfully developed a non-chemical system that not only curbed scale and corrosion, but also offered advantages in water conservation, cost savings and the elimination of toxic chemical discharge. In the system, ozone is produced by an on-site generator and introduced to the cooling tower water. Organic impurities are oxidized, and the dissolved ozone removes bacteria and scale. National Water Management, a NASA licensee, has installed its ozone advantage systems at some 200 cooling towers. Customers have saved money and eliminated chemical storage and discharge.
Davidsen, Claus; Liu, Suxia; Mo, Xingguo; Engelund Holm, Peter; Trapp, Stefan; Rosbjerg, Dan; Bauer-Gottwein, Peter
Few studies address water quality in hydro-economic models, which often focus primarily on optimal allocation of water quantities. Water quality and water quantity are closely coupled, and optimal management with focus solely on either quantity or quality may cause large costs in terms of the oth-er component. In this study, we couple water quality and water quantity in a joint hydro-economic catchment-scale optimization problem. Stochastic dynamic programming (SDP) is used to minimize the basin-wide total costs arising from water allocation, water curtailment and water treatment. The simple water quality module can handle conservative pollutants, first order depletion and non-linear reactions. For demonstration purposes, we model pollutant releases as biochemical oxygen demand (BOD) and use the Streeter-Phelps equation for oxygen deficit to compute the resulting min-imum dissolved oxygen concentrations. Inelastic water demands, fixed water allocation curtailment costs and fixed wastewater treatment costs (before and after use) are estimated for the water users (agriculture, industry and domestic). If the BOD concentration exceeds a given user pollution thresh-old, the user will need to pay for pre-treatment of the water before use. Similarly, treatment of the return flow can reduce the BOD load to the river. A traditional SDP approach is used to solve one-step-ahead sub-problems for all combinations of discrete reservoir storage, Markov Chain inflow clas-ses and monthly time steps. Pollution concentration nodes are introduced for each user group and untreated return flow from the users contribute to increased BOD concentrations in the river. The pollutant concentrations in each node depend on multiple decision variables (allocation and wastewater treatment) rendering the objective function non-linear. Therefore, the pollution concen-tration decisions are outsourced to a genetic algorithm, which calls a linear program to determine the remainder of the decision
Assem, S. van den; W. G. M. Bastiaanssen; Claassen, T.H.L.; R. A. Feddes; M. Menenti; Minderhoud, P.; Nieuwenhuis, G.J.A.; Van Nieuwkoop, J; Stokkom, H.T.C. van; Stokman, N.G.M.; Thunnissen, H.A.M.; Visser, T.N.M.
In modern water management detailed information is required on processes that occur and on the state of water systems, including the way they are influenced by human activities. Remote sensing can contribute significantly to these information. For example, areal patterns of water quality parameters such as suspended solids and algae, and physical and hydrological conditions of the soil can be directly observed. Moreover, with successive synoptical images, remote sensing provides the opportuni...
Schaik, van, G.
This booklet starts out describing how our water management strategy has evolved over the centuries from increasingly defensive measures to an adaptive approach. The second part presents smart, areaspecific examples in planning and zoning of water, land and ecosystems for our coast, rivers, cities and drinking water utilities. The last chapter addresses the importance of communication. The book is richly illustrated and it provides links to interesting sources of further information
Ehteshami, Majid; Peralta, R C
Agricultural chemicals are essential components of agricultural production systems in the United states. Pesticides control weeds, insects, and have had an important role in increasing agricultural productivity in the last 50 years, despite diminishing crop land acreage. The benefits of chemicals use options in agriculture must be balanced against potential contamination of surface water and ground water resources. This study shows the effect of water management practices on pesticide movemen...
The term Water Resources is used to refer to the management and use of water primarily for the benefit of people. Hence, successful management of water resources requires a solid understanding of Hydrology. Cybernetics in Water Resources Management is an endeavor to analyze and enhance the beneficial exploitation of diverse scientific approaches and communication methods; to control the complexity of water management; and to highlight the importance of making right decisions at the right time, avoiding the devastating effects of drought and floods. Recent developments in computer technology and advancement of mathematics have created a new field of system analysis i.e. Mathematical Modeling. Based on mathematical models, several computer based Water Resources System (WRS) Models were developed across the world, to solve the water resources management problems, but these were not adaptable and were limited to computation by a well defined algorithm, with information input at various stages and the management tasks were also formalized in that well structured algorithm. The recent advancements in information technology has revolutionized every field of the contemporary world and thus, the WRS has also to be diversified by broadening the knowledge base of the system. The updation of this knowledge should be a continuous process acquired through the latest techniques of networking from all its concerned sources together with the expertise of the specialists and the analysis of the practical experiences. The system should then be made capable of making inferences and shall have the tendency to apply the rules based on the latest information and inferences in a given stage of problem solving. Rigid programs cannot adapt to changing conditions and new knowledge. Thus, there is a need for an evolutionary development based on mutual independence of computational procedure and knowledge with capability to adapt itself to the increasing complexity of problem. The subject
Hüffmeyer, N.; Berlekamp, J.; Klasmeier, J.
used to demonstrate the effect of specific mitigation strategies such as improved treatment of rainwater, reduction of metal products exposed to rain or reduced input from mine drainage. The model can thus be a valuable tool for setting up management plans as required in the Water Framework Directive with a special emphasis on promising mitigation strategies in case of exceedance of target values. 4. References  Directive 2000/60/EC of the European Parliament and of the Council (EU Water Framework Directive)  Feijtel T.C.J., Boeije G., Matthies M., Young A., Morris G., Gandolfi C., Hansen B., Fox K., Holt M., Koch V., Schröder R., Cassani G., Schowanek D., Rosenblom J. and Niessen H.; Chemosphere 34, 2351-2374, 1997. Acknowledgement - We would like to thank the International Zinc Association (IZA) and the European Copper Insitute (ECI) for financial support.
US Fish and Wildlife Service, Department of the Interior — Content includes 2000 weather summary, 2000 water management summaries, 2001 water availability forecast, and 2001 water management strategy.
US Fish and Wildlife Service, Department of the Interior — Content includes 1999 weather summary, 1999 water management summaries, 2001 water availability forecast, and 2001 water management strategy.
US Fish and Wildlife Service, Department of the Interior — Content includes 1998 weather summary, 1998 water management summaries, 1999 water availability forecast, and 1999 water management strategy.
Orprecio, J.; Rola, Agnes C.; Deutsch, William; Coxhead, Ian; Sumbalan, Antonio
Metadata only record The rapid growth in demand for water by the agricultural, industrial and household sectors will place greater pressure on Philippine water supplies in the future. Among the many water management issues, surface water management, watershed management or more precisely, river basin management is prominent in both the local and national scenes.
number of the countries that have recently begun to consider the introduction of nuclear power are in water scarce regions, which would certainly limit the possibility for deployment of nuclear power plants, in turn hindering these countries' development and energy security. Thus, there is a large incentive to enhance efforts to introduce innovative water use, water management practices and related technologies. Water management for nuclear power plants is gaining interest in IAEA Member States as an issue of vital importance for the deployment of nuclear power. Recent experience has shown that some nuclear power plants are susceptible to prolonged drought conditions, forcing reactors to be shut down or power to be reduced to a minimal level. In some cases, environmental issues have resulted in regulations that limit the possibility for water withdrawal as well as water discharge. Regarding the most common design for cooling nuclear power plants, this has led to a complicated siting procedure for new plants and expensive retrofits for existing ones. The IAEA has already provided its Member States with reports and documents that address the issue. At the height of nuclear power expansion in the 1970s, the need for guidance in the area resulted in publications such as Thermal Discharges at Nuclear Power Stations - Their Management and Environmental Impact (Technical Reports Series No. 155) and Environmental Effects of Cooling Systems (Technical Reports Series No. 202). Today, amid the so-called nuclear renaissance, it is of vital importance to offer guidance to the Member States on the issues and possibilities that nuclear power water management brings. Management of water at nuclear power plants is an important subject during all phases of the construction, operation and maintenance of any nuclear power plant. Water management addresses the issue of securing water for condenser cooling during operation, for construction (during the flushing phase), and for inventory
Full Text Available With global climate changes intensifying, the hydrological response to climate changes has attracted more attentions. It is beneficial not only for hydrology and ecology but also for water resources planning and management to reveal the impacts of climate change on runoff. It is of great significance of climate elasticity of runoff to estimate the impacts of climatic factors on runoff. In addition, there are large spatial variations in climate type and geography characteristics over China. To get a better understanding the spatial variation of runoff response to climate variables change and detect the dominant climatic factor driving annual runoff change, we chose the climate elasticity method proposed by Yang and Yang (2011, where the impact of the catchment characteristics on runoff was represented by a parameter n. The results show that the dominant climatic factor driving annual runoff is precipitation in the most part of China, net radiation in the lower reach of Yangtze River Basin, the Pearl River Basin, the Huai River Basin and the southeast area, and wind speed in part of the northeast China.
Huang, Zhongwei; Yang, Hanbo; Yang, Dawen
With global climate changes intensifying, the hydrological response to climate changes has attracted more attention. It is beneficial not only for hydrology and ecology but also for water resource planning and management to understand the impact of climate change on runoff. In addition, there are large spatial variations in climate type and geographic characteristics across China. To gain a better understanding of the spatial variation of the response of runoff to changes in climatic factors and to detect the dominant climatic factors driving changes in annual runoff, we chose the climate elasticity method proposed by Yang and Yang (2011). It is shown that, in most catchments of China, increasing air temperature and relative humidity have negative impacts on runoff, while declining net radiation and wind speed have positive impacts on runoff, which slow the overall decline in runoff. The dominant climatic factors driving annual runoff are precipitation in most parts of China, net radiation mainly in some catchments of southern China, air temperature and wind speed mainly in some catchments in northern China.
Saskia M. van Ruth
Full Text Available Seafood is an important food source for many. Consumers should be entitled to an informed choice, and there is growing concern about correct composition labeling of seafood. Due to its high price, it has been shown to be vulnerable to adulteration. In the present study, we focus on moisture levels in seafood. Moisture and crude protein contents of chilled and frozen cod, pangasius, salmon, shrimp and tilapia purchased from various retail outlets in the Netherlands were examined by reference methods and the values of which were compared with the reported data from other studies in literature. Significant differences in proximate composition were determined for different species and between chilled and frozen products of the same species. Pangasius products showed the highest moisture contents in general (86.3 g/100 g, and shrimp products revealed the largest differences between chilled and frozen products. Comparison with literature values and good manufacturing practice (GMP standards exposed that, generally, chilled pangasius, frozen pangasius and frozen shrimp products presented considerably higher moisture and lower crude protein/nitrogen contents than those found in other studies. From the GMP standards, extraneous water was estimated on average at 26 g/100 g chilled pangasius product, and 25 and 34 g/100 g product for frozen shrimp and pangasius products, respectively.
US Fish and Wildlife Service, Department of the Interior — Content of the Ruby Lake NWR Water Management Plan includes information on refuge background, objectives and management strategies, and water management program...
Gaßmann, Matthias; Olsson, Oliver; Bauer, Melanie
Pesticides are of great concern in hydrological catchments all over the world. On the one hand they are necessary to guarantee stable agricultural production for an increasing population. On the other hand they endanger life of aquatic animals and freshwater resources. However, not only pesticides but also their degradation products, the metabolites, are toxic to the environment, in some cases even more than the parent material. Thus, it is necessary to optimize pesticide application and management of agricultural land (e.g. grass strips, erosion prevention) with respect and according to their behaviour and degradation in hydrological catchments. Modelling provides a sound tool for assessing the impacts of pesticide management changes on pesticide behaviour at the field and in consecutively surface waters. Most of the various models available in literature do not consider metabolism. This study introduces an applicable integrated model assessing the fate and release of a pesticide and one metabolite at the field and in surface waters of a hydrological catchment. For the development of the field release model, the single-equation pesticide release formula by the OECD (2000) was used, which combines sorption and degradation in one equation. The part of the equation calculating the degradation forms the input of a second OECD equation representing the metabolite with its own parameters. A fraction can be specified describing how much of the degradation product is transferred to the specific metabolite. The river network is simulated with a further development of the MOHID River Network model (MRN). The integration of a pesticide type and a metabolite, with their degradation and volatilization processes are the main improvements of the hydrodynamic channel model. Following, the combined model was set up to the Israeli part of the Upper Jordan River basin, especially the Hula valley. According to the local hydrological conditions, a linear storage with a threshold was
Thomas K. Alexandridis
Full Text Available Despite playing a critical role in the division of precipitation between runoff and infiltration, soil moisture (SM is difficult to estimate at the catchment scale and at frequent time steps, as is required by many hydrological, erosion and flood simulation models. In this work, an integrated methodology is described to estimate SM at the root zone, based on the remotely-sensed evaporative fraction (Λ and ancillary information on soil and meteorology. A time series of Terra MODIS satellite images was used to estimate SM maps with an eight-day time step at a 250-m spatial resolution for three diverse catchments in Europe. The study of the resulting SM maps shows that their spatial variability follows the pattern of land cover types and the main geomorphological features of the catchment, and their temporal pattern follows the distribution of rain events, with the exception of irrigated land. Field surveys provided in situ measurements to validate the SM maps’ accuracy, which proved to be variable according to site and season. In addition, several factors were analyzed in order to explain the variation in the accuracy, and it was shown that the land cover type, the soil texture class, the temporal difference between the datasets’ acquisition and the presence of rain events during the measurements played a significant role, rather than the often referred to scale difference between in situ and satellite observations. Therefore, the proposed methodology can be used operationally to estimate SM maps at the catchment scale, with a 250-m spatial resolution and an eight-day time step.
Full Text Available Problems related to water management in Costa Rica have an economic origin. Partly, as a consequence of a natural condition of water richness, as well as the concept of public service with fees that don´t promote neither investment nor efficiency of water resource use. Solutions must be targeted toward the economic conditions generating pollution, little efficiency, and lesser infiltration area. Water social cost regarding its use and pollution must be recognized and paid. The water user fee and pollution fee represent a step forward. A higher application of this kind of instruments will generate profit-benefit to the economy and might encourage the protection of the environment and natural resources.
Full Text Available Model coupling requires a thorough conceptualisation of the coupling strategy, including an exact definition of the individual model domains, the "transboundary" processes and the exchange parameters. It is shown here that in the case of coupling groundwater flow and hydrological models – in particular on the regional scale – it is very important to find a common definition and scale-appropriate process description of groundwater recharge and baseflow (or "groundwater runoff/discharge" in order to achieve a meaningful representation of the processes that link the unsaturated and saturated zones and the river network. As such, integration by means of coupling established disciplinary models is problematic given that in such models, processes are defined from a purpose-oriented, disciplinary perspective and are therefore not necessarily consistent with definitions of the same process in the model concepts of other disciplines. This article contains a general introduction to the requirements and challenges of model coupling in Integrated Water Resources Management including a definition of the most relevant technical terms, a short description of the commonly used approach of model coupling and finally a detailed consideration of the role of groundwater recharge and baseflow in coupling groundwater models with hydrological models. The conclusions summarize the most relevant problems rather than giving practical solutions. This paper aims to point out that working on a large scale in an integrated context requires rethinking traditional disciplinary workflows and encouraging communication between the different disciplines involved. It is worth noting that the aspects discussed here are mainly viewed from a groundwater perspective, which reflects the author's background.
Ertsen, Maurits; Strohschein, Paul; Onencan, Abby; van de Giesen, Nick
Water conservation is a high priority in the drier areas of sub-Saharan Africa. Storage of water from the rainy season to the dry season, or even from wet years to dry years is highly important. Small multi-purpose sub-surface water reservoirs recharged through infiltration are used to provide water for humans, livestock and crops in the Kitui region in Kenya. The groundwater dams obstruct the natural flow of water in wet seasons or periods, and provide storage of water during dry seasons or periods. This paper links the hydrology of the sand-storage dams to human agency. When is a dam a success in hydrological terms? When it provides water every year? Every two years? How many months? What happens in very dry years? Obviously, water use will decrease the water volume and thus the water level upstream of the dam, but to what extent typically depends on the amounts used compared to the size of the dam and the water use itself. Longer-term effects on groundwater levels to be expected depend strongly on the way the water is used. Household water use and river banks infiltration increasing seasonal storage can go hand in hand. However, when water in dams is used for higher water demanding activities such as (motorized) irrigation, the infiltration effect into banks may be minimal. A dam can also be "too effective" and decrease water availability for water users further downstream. It is unlikely, however, that an individual farmer will effect on the downstream users of the resources he/she is tapping, but a network of dams as in Kitui may have considerable effect. Measurements indicate that only about 2% to 3% of the total yearly runoff within the catchment directly associated with a single dam is stored in its reservoir. Therefore only this small percentage of the total flow of a seasonal river with dams is blocked. The paper will detail these general concepts with a case study of the Kiindu catchment. The hydrology of the Kiindu catchment is dependent on different
David, Vaclav; Davidová, Tereza
presented in this contribution has been carried out within the research projects NAZV KUS QJ1220233 'Assessment of former pond systems with aim to achieve sustainable management of water and soil resources in the Czech Republic' and SGS14/180/OHK1/3T/11 'Rainfall-runoff, erosion and transport processes - experimental research'. All the support is highly acknowledged.
Rauch, W.; Harremoës, Poul
system provides useful information for water quality management. It is possible to identify the system parameters that contain engineering significance. Continuous simulation of the system performance indicates that the combined nitrogen loading is dominated by the wastewater treatment plant during dry...... weather, while the overflow from the combined sewer system plays a minor role. Oxygen depletion in urban rivers is caused by intermittent discharges from both sewer system and wastewater treatment plant. Neglecting one of them in the evaluation of the environmental impact gives a wrong impression of total......The basic features of integrated urban water quality management by means of deterministic modeling are outlined. Procedures for the assessment of the detrimental effects in the recipient are presented as well as the basic concepts of an integrated model. The analysis of a synthetic urban drainage...
Querini, Giulio; Creaco, Salvo
Water sustainability needs a balance between demand and availability: 1) Water demand management: demand may be managed by suppliers and regulations responsible persons, using measures like invoicing, consumptions measurement and users education in water conservation measures; 2) Augmentation of water supply: availibility may be augmented by infrastructural measures, waste water reuse, non-conventional resources and losses reduction. Water Demand Management is about achieving a reduction in t...
Philippe Ker Rault; Wil Thissen; Jill Slinger; Heleen Vreugdenhil
Pilot projects appear in many forms in policy making and management. In an effort to understand the nature and use of pilot projects and improve their effectiveness, we undertake a practice-based and theoretical study of the pilot project phenomenon. First, we examine the roles assigned to pilot projects in the policy development literature and explore their use in a Dutch water innovation platform. Second, we determine characteristics of pilot projects to deepen insights into the nature of t...
Ali, Muhammad; Montzka, Carsten; Graf, Alexander; Jonard, Francois; Vereecken, Harry
Being a major component of the hydrological cycle, evapotranspiration (ET) and its spatial and temporal distribution are of major importance for hydrological and meteorological applications. Owing to its dependency on the amount and duration of incoming solar radiations and other meteorological parameters, changes in ET may occur on short time scales (less than an hour). Therefore, monitoring the temporal and spatial anomalies in evapotranspiration is very important. Conventional methods for ET estimation are restricted to local measurements, and hence unable to capture the spatial distribution of ET on heterogeneous surfaces. However, they are useful for validating ET derived from remote sensing data over large areas. To estimate evapotranspiration on a regional scale, two main approaches are available i) Application of a water balance approach to ground-based catchment-scale measurements and ii) Application of an energy balance approach to remote sensing data. The energy balance approach is based on the distribution of energy on the earth surface and the availability of the amount of latent heat to cause evapotranspiration (transpiration and evaporation) from plants and soil surface. Several approaches have been presented in literature but in this study we used a two source model (TSM) approach to calculate surface energy fluxes (e.g., latent heat, sensible heat and ground heat fluxes) for canopy and soil. The TSM assumes that soil and vegetation affect the microclimate within the soil-canopy system and therefore separate resistances are calculated for heat exchange from canopy and soil. In TSM net radiations are partitioned in to soil and canopy components (Rns, Rnc) and have been revised several times for improving shortwave and longwave radiation exchange between canopy and soil. TSM uses satellite derived directional radiometric surface temperature [TR(θ)] as composite of the soil and canopy temperatures (TS and TC respectively). In this study
Tran, Quoc Quan; Willems, Patrick; Pannemans, Bart; Blanckaert, Joris; Pereira, Fernando; Nossent, Jiri; Cauwenberghs, Kris; Vansteenkiste, Thomas
validation on spatial results was done for the groundwater head values at observation wells. To ensure that the lumped model can produce results as accurate as the spatially distributed models or close regardless to the number of parameters and implemented physical processes, it was checked whether the structure of the lumped models had to be adjusted. The concept has been implemented in a PCRaster - Python platform and tested for two Belgian case studies (catchments of the rivers Dijle and Grote Nete). So far, use is made of existing model structures (NAM, PDM, VHM and HBV). Acknowledgement: These results were obtained within the scope of research activities for the Flemish Environment Agency (VMM) - division Operational Water Management on "Next Generation hydrological modeling", in cooperation with IMDC consultants, and for Flanders Hydraulics Research (Waterbouwkundig Laboratorium) on "Effect of climate change on the hydrological regime of navigable watercourses in Belgium".
US Fish and Wildlife Service, Department of the Interior — This memorandum outlines the management strategy for water level management on St. Vincent Island in 2007. A table of planned water levels for each month is...
Weyer, Christina; Peiffer, Stefan; Schulze, Kerstin; Borken, Werner; Lischeid, Gunnar
From a biogeochemical perspective, catchments can be regarded as reactors that transform the input of various substances via precipitation or deposition as they pass through soils and aquifers towards draining streams. Understanding and modeling the variability of solute concentrations in catchment waters require the identification of the prevailing processes, determining their respective contribution to the observed transformation of substances, and the localization of "hot spots", that is, the most reactive areas of catchments. For this study, we applied a non-linear variant of the Principle Component Analysis, the Isometric Feature Mapping (Isomap), to a data set composed of 1686 soil solution, groundwater and stream water samples and 16 variables (Al, Ca, Cl, Fe, K, Mg, Mn, Na, NH4, NO3, SO4, total S, Si, DOC, electric conductivity and pH values) from the Lehstenbach catchment in Germany. The aim was (i) to assess the contribution of the prevailing biogeochemical processes to the variability of solute concentrations in water samples taken from soils, in groundwater and in stream water in a catchment and (ii) to identify hot spots at the catchment scale with respect to 16 solutes along different flow paths. The first three dimensions of the Isomap analysis explained 48%, 30% and 11%, respectively, i.e. 89% of the variance in the data set. Scores of the first three dimensions could be ascribed to three predominating bundles of biogeochemical processes: (i) redox processes, (ii) acid-induced podzolization, and (iii) weathering processes. In general, the upper 1 m topsoil layer could be considered as hot spots along flow paths from upslope soils and in the wetland, although with varying extents for the different prevailing biogeochemical processes. Nearly 67% and 97% of the variance with respect to redox processes and acid induced podzolization could be traced back to hot spots, respectively, representing less than 2% of the total spatial volume of the catchment
Fatkhutdinov, Aybulat; Stefan, Catalin; Junghanns, Ralf
Model-based decision support systems are considered to be reliable and time-efficient tools for resources management in various hydrology related fields. However, searching and acquisition of the required data, preparation of the data sets for simulations as well as post-processing, visualization and publishing of the simulations results often requires significantly more work and time than performing the modeling itself. The purpose of the developed software is to combine data storage facilities, data processing instruments and modeling tools in a single platform which potentially can reduce time required for performing simulations, hence decision making. The system is developed within the INOWAS (Innovative Web Based Decision Support System for Water Sustainability under a Changing Climate) project. The platform integrates spatially distributed catchment scale rainfall - runoff, infiltration and groundwater flow models with data storage, processing and visualization tools. The concept is implemented in a form of a web-GIS application and is build based on free and open source components, including the PostgreSQL database management system, Python programming language for modeling purposes, Mapserver for visualization and publishing the data, Openlayers for building the user interface and others. Configuration of the system allows performing data input, storage, pre- and post-processing and visualization in a single not disturbed workflow. In addition, realization of the decision support system in the form of a web service provides an opportunity to easily retrieve and share data sets as well as results of simulations over the internet, which gives significant advantages for collaborative work on the projects and is able to significantly increase usability of the decision support system.
M. G. Hutchins
Full Text Available In recent years, a co-ordinated programme of data collection has resulted in the collation of sub-hourly time-series of hydrological, sediment and phosphorus loss data, together with soil analysis, cropping and management information for two small ( Keywords: phosphorus, erosion, process-based modelling, agriculture
Klaar, Megan; Laize, Cedric; Maddock, Ian; Acreman, Mike; Tanner, Kath; Peet, Sarah
A key challenge for environmental managers is the determination of environmental flows which allow a maximum yield of water resources to be taken from surface and sub-surface sources, whilst ensuring sufficient water remains in the environment to support biota and habitats. It has long been known that sensitivity to changes in water levels resulting from river and groundwater abstractions varies between rivers. Whilst assessment at the catchment scale is ideal for determining broad pressures on water resources and ecosystems, assessment of the sensitivity of reaches to changes in flow has previously been done on a site-by-site basis, often with the application of detailed but time consuming techniques (e.g. PHABSIM). While this is appropriate for a limited number of sites, it is costly in terms of money and time resources and therefore not appropriate for application at a national level required by responsible licensing authorities. To address this need, the Environment Agency (England) is developing an operational tool to predict relationships between physical habitat and flow which may be applied by field staff to rapidly determine the sensitivity of physical habitat to flow alteration for use in water resource management planning. An initial model of river sensitivity to abstraction (defined as the change in physical habitat related to changes in river discharge) was developed using site characteristics and data from 66 individual PHABSIM surveys throughout the UK (Booker & Acreman, 2008). By applying a multivariate multiple linear regression analysis to the data to define habitat availability-flow curves using resource intensity as predictor variables, the model (known as RAPHSA- Rapid Assessment of Physical Habitat Sensitivity to Abstraction) is able to take a risk-based approach to modeled certainty. Site specific information gathered using desk-based, or a variable amount of field work can be used to predict the shape of the habitat- flow curves, with the
W. Korres; Reichenau, T. G.; Schneider, K; P. Fiener; Koyama, C. N.; Bogena, Heye; Cornelissen, T.; Baatz, R.; M. Herbst; B. Diekkrüger; H. Vereecken
Soil moisture is a key variable in hydrology, meteorology and agriculture. It is influenced by many factors, such as topography, soil properties, vegetation type, management, and meteorological conditions. The role of these factors in controlling the spatial patterns and temporal dynamics is often not well known. The aim of the current study is to analyze spatio-temporal soil moisture patterns acquired across a variety of land use types, on different spatial scales (plot to meso-scale catchme...
Full Text Available Water management system include all activities and works which providing the administration of public domain of water, with local / national interest, and qualitative, quantitative and sustainable management of water resources. Hydrotechnical arrangements, consisting of a set of hydraulic structures, produce both a favorable and unfavorable influences on environment. Their different constructive and exploitation solutions exercise a significantly impact on the environment. Therefore the advantages and disadvantages of each solution must be weighed and determined to materialize one or other of them seriously argued.The optimization of water management systems is needed to meet current and future requirements in the field of rational water management in the context of integrated water resources management. Optimization process of complex water management systems includes several components related to environmental protection, technical side and the business side. This paper summarizes the main aspects and possibilities of optimization of existing water management systems and those that are to be achieved.
Kraft, P.; Breuer, L.; Vaché, K. B.; Frede, H.-G.
Modeling nutrient fluxes in a catchment is a complex and interdisciplinary task. Building and improving simulation tools for such complex systems is often constraint by the expertise of the engaged scientists: Since different fields of science are involved like vadose zone and ground water hydrology, plant growth, atmospheric exchange, soil chemistry, soil microbiology, stream physics and stream chemistry, a single work group cannot excel in all parts. As a result, either parts of the system, where no scientist involved is an expert, include rough simplifications, or a "complete" group is too big for maintaining the system over a longer period. However, many approaches exist to create complex models that integrate processes for all sub domains. But a tight integration bears the problem of freezing a specific state of science in the complex system. A model infrastructure, which takes the complex feedback loops across domain boundaries (e.g. soil moisture and plant growth) into consideration and is still flexible enough for adoption to new findings in any of the scientific fields is therefore needed. This type of infrastructure can be obtained by a set of independent, but connectible models. The new Catchment Model Framework (cmf), a module for subsurface water and solute transport, is an example of an independent yet open and easily extendible framework for the simulation of water and solute transport processes. Openness is gained by implementing the model as an extension to the Python programming language. Coupling of cmf with models also providing an interface to the Python language dealing with other system compartments, as plant growth, biogeochemical or atmospheric dispersion models etc. can easily be done. The models used in the coupling process can either be spatial explicit models, plot scale models with one instance per mesh node of the landscape model or pure reaction functions using the integration methods of cmf. The concept of extending an existing and
T. Doppler; L. Camenzuli; G. Hirzel; Krauss, M; A. Lück; Stamm, C
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...
T. Doppler; L. Camenzuli; G. Hirzel; Krauss, M; A. Lück; Stamm, C
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 pollutio...
Möck, Christian; Hunkeler, Daniel; Brunner, Philip
There is strong evidence that climate is changing and will affect the water resources. A major question arising from the evaluation of climate change (CC) impacts on groundwater resources is to what extent groundwater recharge will change. Given that for Switzerland, climate models predict more frequent hot and dry summers in the future while precipitation will tend to increase in winter, a special attention was given to possible changes in the seasonal distribution of recharge. However, to p...
Fatichi, Simone; Zeeman, Matthias; Fuhrer, Jürg; Burlando, Paolo
Grassland and pastures are very typical land uses in subalpine and alpine environments. Grass is typically subjected to management practices that can change the biophysical structure of the plant canopy through defoliation and alter soil hydraulic properties. These changes are expected to impact hydrological and energy fluxes as well as vegetation primary productivity. In this study a mechanistic model is used to investigate the effects of management practices (grass cut, grazing, and the consequent soil compaction due to treading by animals) on water and carbon dynamics. The model is first confirmed using energy, water, and carbon fluxes measured at three eddy covariance stations above grasslands in Switzerland and discharge measured in a small experimental catchment. Successively, a series of virtual experiments are conceived to elucidate the impacts of management scenarios at the plot and catchment scales. Numerical results show that only the most severe management actions such as low grass cuts or heavy grazing intensities are able to influence the long-term hydrological behavior. Moderate grassland management practices are unlikely to be effective in modifying the system both at the local and catchment scale. An important exception is represented by the short-term effect of soil compaction that can reduce infiltration capacity leading to peak flow considerably higher than in undisturbed conditions. The productivity of vegetation in absence of nutrient limitation is affected by the different management scenarios with tolerable disturbances that lead to higher aboveground net primary production. Such a result can have important consequences in terms of grassland management planning.
Full Text Available Hysteresis is a rate-independent non-linearity that is expressed through thresholds, switches, and branches. Exceedance of a threshold, or the occurrence of a turning point in the input, switches the output onto a particular output branch. Rate-independent branching on a very large set of switches with non-local memory is the central concept in the new definition of hysteresis. Hysteretic loops are a special case. A self-consistent mathematical description of hydrological systems with hysteresis demands a new non-linear systems theory of adequate generality. The goal of this paper is to establish this and to show how this may be done. Two results are presented: a conceptual model for the hysteretic soil-moisture characteristic at the pedon scale and a hysteretic linear reservoir at the catchment scale. Both are based on the Preisach model. A result of particular significance is the demonstration that the independent domain model of the soil moisture characteristic due to Childs, Poulavassilis, Mualem and others, is equivalent to the Preisach hysteresis model of non-linear systems theory, a result reminiscent of the reduction of the theory of the unit hydrograph to linear systems theory in the 1950s. A significant reduction in the number of model parameters is also achieved. The new theory implies a change in modelling paradigm.
Gabrielli, C. P.; McDonnell, J. J.; Jarvis, W. T.
SummaryBedrock groundwater dynamics in headwater catchments are poorly understood and poorly characterized. Direct hydrometric measurements have been limited due to the logistical challenges associated with drilling through hard rock in steep, remote and often roadless terrain. We used a new portable bedrock drilling system to explore bedrock groundwater dynamics aimed at quantifying bedrock groundwater contributions to hillslope flow and catchment runoff. We present results from the Maimai M8 research catchment in New Zealand and Watershed 10 (WS10) at the H.J. Andrews Experimental Forest in Oregon, USA. Analysis of bedrock groundwater at Maimai, through a range of flow conditions, revealed that the bedrock water table remained below the soil-bedrock interface, indicating that the bedrock aquifer has minimal direct contributions to event-based hillslope runoff. However, the bedrock water table did respond significantly to storm events indicating that there is a direct connection between hillslope processes and the underlying bedrock aquifer. WS10 groundwater dynamics were dominated by fracture flow. A highly fractured and transmissive zone within the upper one meter of bedrock conducted rapid lateral subsurface stormflow and lateral discharge. The interaction of subsurface stormflow with bedrock storage directly influenced the measured hillslope response, solute transport and computed mean residence time. This research reveals bedrock groundwater to be an extremely dynamic component of the hillslope hydrological system and our comparative analysis illustrates the potential range of hydrological and geological controls on runoff generation in headwater catchments.
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
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
Ishiwatari, Mikio; Wataya, Eiko; Shin, Taesun; Kim, Daeil; Song, Jiseon; Kim, Seyi
Water security and water quality affect numerous economic sectors and areas: agriculture, energy, disaster management, and others. Countries need balanced and integrated approaches that are economically, environmentally, and socially sustainable. Threats related to climate change have added to the complexity, and to the importance, of water resource management. Korea’s integrated water resources management approach since the 1990s reflects the country’s “green” climate-resilient development ...
Xiangfeng Zhang; Lei Gao; Damian Barrett; Yun Chen
To move towards sustainable development, the mining industry needs to identify better mine water management practices for reducing raw water use, increasing water use efficiency, and eliminating environmental impacts in a precondition of securing mining production. However, the selection of optimal mine water management practices is technically challenging due to the lack of scientific tools to comprehensively evaluate management options against a set of conflicting criteria. This work has pr...
Adam, J. C.; Tague, C.; Liu, M.; Garcia, E.; Choate, J.; Mullis, T.; Hull, R.; Vaughan, J. K.; Kalyanaraman, A.; Nguyen, T.
With a focus on the U.S. Pacific Northwest (PNW), BioEarth is an Earth System Model (EaSM) currently in development that explores the interactions between coupled C:N:H2O dynamics and resource management actions at the regional scale. Capturing coupled biogeochemical processes within EaSMs like BioEarth is important for exploring the response of the land surface to changes in climate and resource management actions; information that is important for shaping decisions that promote sustainable use of our natural resources. However, many EaSM frameworks do not adequately represent landscape-scale ( 10 km) are necessitated by computational limitations. Spatial heterogeneity in a landscape arises due to spatial differences in underlying soil and vegetation properties that control moisture, energy and nutrient fluxes; as well as differences that arise due to spatially-organized connections that may drive an ecohydrologic response by the land surface. While many land surface models used in EaSM frameworks capture the first type of heterogeneity, few account for the influence of lateral connectivity on land surface processes. This type of connectivity can be important when considering soil moisture and nutrient redistribution. The RHESSys model is utilized by BioEarth to enable a "bottom-up" approach that preserves fine spatial-scale sensitivities and lateral connectivity that may be important for coupled C:N:H2O dynamics over larger scales. RHESSys is a distributed eco-hydrologic model that was originally developed to run at relatively fine but computationally intensive spatial resolutions over small catchments. The objective of this presentation is to describe two developments to enable implementation of RHESSys over the PNW. 1) RHESSys is being adapted for BioEarth to allow for moderately coarser resolutions and the flexibility to capture both types of heterogeneity at biome-specific spatial scales. 2) A Kepler workflow is utilized to enable RHESSys implementation over
Bernhardt, Emily S; Palmer, Margaret A
River restoration is an increasingly common approach utilized to reverse past degradation of freshwater ecosystems and to mitigate the anticipated damage to freshwaters from future development and resource-extraction activities. While the practice of river restoration has grown exponentially over the last several decades, there has been little empirical evaluation of whether restoration projects individually or cumulatively achieve the legally mandated goals of improving the structure and function of streams and rivers. New efforts to evaluate river restoration projects that use channel reconfiguration as a methodology for improving stream ecosystem structure and function are finding little evidence for measurable ecological improvement. While designed channels may have less-incised banks and greater sinuousity than the degraded streams they replace, these reach-scale efforts do not appear to be effectively mitigating the physical, hydrological, or chemical alterations that are responsible for the loss of sensitive taxa and the declines in water quality that typically motivate restoration efforts. Here we briefly summarize this new literature, including the collection of papers within this Invited Feature, and provide our perspective on the limitations of current restoration. PMID:21939034
Flipo, Nicolas; Even, Stéphanie; Poulin, Michel; Théry, Sylvain; Ledoux, Emmanuel
Nitrates fluxes in the Grand Morin basin (1200 km(2)), that is subjected to intense agricultural pressure, are considered using in-stream observations (around 250 sampling days over 5 years) and physically based simulations using the CAWAQS model (CAtchment WAter Quality Simulator). In-stream nitrate concentration averaged 6 mg N L(-1), increasing by approximately 0.2 mg N L(-1) yr(-1) around this value (period 1991-1996). Our results show that, over the period of 1991-1996, the differences between in-stream observed nitrate concentrations and simulated nitrate concentrations result from nitrate losses at the basin scale. These losses are due to denitrification by transfer through wetlands, alluvial plains, the hyporheic zone, and by benthic processes in rivers. A mean annual mass balance at the basin scale indicates that 40% of the infiltration flux (3360 kg N km(-2) yr(-1)) is removed from the system via the river network, 40% is stored in aquifers and 20% is lost by denitrification (period 1991-1996). PMID:17331565
Dolan, Tom; Pullan, Stephanie; Whelan, Mick; Parsons, David
Diffuse inputs from agriculture are commonly the main source of pesticide contamination in surface water and may have implications for the quality of treated drinking water. After privatisation in 1991, UK water companies primarily focused on the provision of sufficient water treatment to reduce the risk of non-compliance with the European Drinking Water Directive (DWD), under which all pesticide concentrations must be below 0.1µg/l and UK Water Supply Regulations for the potable water they supply. Since 2000, Article 7 of the Water Framework Directive (WFD) has begun to drive a prevention-led approach to compliance with the DWD. As a consequence water companies are now more interested in the quality of 'raw' (untreated) water at the point of abstraction. Modelling (based upon best available estimates of cropping, pesticide use, weather conditions, pesticide characteristics, and catchment characteristics) and monitoring of raw water quality can both help to determine the compliance risks associated with the quality of this 'raw' water resource. This knowledge allows water companies to prioritise active substances for action in their catchments, and is currently used in many cases to support the design of monitoring programmes for pesticide active substances. Additional value can be provided if models are able to help to identify the type and scale of catchment management interventions required to achieve DWD compliance for pesticide active substances through pollution prevention at source or along transport pathways. These questions were explored using a simple catchment-scale pesticide fate and transport model. The model employs a daily time-step and is semi-lumped with calculations performed for soil type and crop combinations, weighted by their proportions within the catchment. Soil properties are derived from the national soil database and the model can, therefore, be applied to any catchment in England and Wales. Various realistic catchment management
P. G. Whitehead; Heathwaite, A. L.; N. J. Flynn; Wade, A. J.; Quinn, P. F.
International audience A semi-distributed model, INCA, has been developed to determine the fate and distribution of nutrients in terrestrial and aquatic systems. The model simulates nitrogen and phosphorus processes in soils, groundwaters and river systems and can be applied in a semi-distributed manner at a range of scales. In this study, the model has been applied at field to sub-catchment to whole catchment scale to evaluate the behaviour of biosolid-derived losses of P in agricultural ...
Hearne, Robert R.
Mexico's water management institutions are undergoing a gradual but dramatic change that corresponds to other changes in Mexican society. Implementing these changes has led to the creation of new institutions, including river basin councils, state water commissions, aquifer management committees, and water user associations. Established institutions such as the National Water Commission have accepted new roles. Some of these changes can be considered to be superficial, but this institutional change is impressive. Successful practices can be identified. These include the transfer of the management of large irrigation districts to the users, the periodic practice of establishing a national water plan, the cautious approach to private sector participation in water supply and sanitation, and the national registry of water use. Remaining challenges include weak river basin and aquifer management organizations, overexploitation of key aquifers, polluted surface water, and the inability of water markets to facilitate intersectoral water transfers.
Skaugen, T.; Mengistu, Z.
In this study we propose a new formulation of subsurface water storage dynamics for use in rainfall-runoff models. Under the assumption of a strong relationship between storage and runoff, the temporal distribution of storage is considered to have the same shape as the distribution of observed recessions (measured as the difference between the log of runoff values). The mean subsurface storage is estimated as the storage at steady-state, where moisture input equals the mean annual runoff. An important contribution of the new formulation is that its parameters are derived directly from observed recession data and the mean annual runoff and hence estimated prior to calibration. Key principles guiding the evaluation of the new subsurface storage routine have been (a) to minimize the number of parameters to be estimated through the, often arbitrary fitting to optimize runoff predictions (calibration) and (b) maximize the range of testing conditions (i.e. large-sample hydrology). The new storage routine has been implemented in the already parameter parsimonious Distance Distribution Dynamics (DDD) model and tested for 73 catchments in Norway of varying size, mean elevations and landscape types. Runoff simulations for the 73 catchments from two model structures; DDD with calibrated subsurface storage and DDD with the new estimated subsurface storage were compared. No loss in precision of runoff simulations was found using the new estimated storage routine. For the 73 catchments, an average of the Nash-Sutcliffe Efficiency criterion of 0.68 was found using the new estimated storage routine compared with 0.66 using calibrated storage routine. The average Kling-Gupta Efficiency criterion was 0.69 and 0.70 for the new and old storage routine, respectively. Runoff recessions are more realistically modelled using the new approach since the root mean square error between the mean of observed and simulated recessions was reduced by almost 50 % using the new storage routine.
Davenport, I. J.; Silgram, M.; Robinson, J. S.; Lamb, A.; Settle, J. J.; Willig, A.
Remote sensing can potentially provide information useful in improving pollution transport modelling in agricultural catchments. Realisation of this potential will depend on the availability of the raw data, development of information extraction techniques, and the impact of the assimilation of the derived information into models. High spatial resolution hyperspectral imagery of a farm near Hereford, UK is analysed. A technique is described to automatically identify the soil and vegetation endmembers within a field, enabling vegetation fractional cover estimation. The aerially-acquired laser altimetry is used to produce digital elevation models of the site. At the subfield scale the hypothesis that higher resolution topography will make a substantial difference to contaminant transport is tested using the AGricultural Non-Point Source (AGNPS) model. Slope aspect and direction information are extracted from the topography at different resolutions to study the effects on soil erosion, deposition, runoff and nutrient losses. Field-scale models are often used to model drainage water, nitrate and runoff/sediment loss, but the demanding input data requirements make scaling up to catchment level difficult. By determining the input range of spatial variables gathered from EO data, and comparing the response of models to the range of variation measured, the critical model inputs can be identified. Response surfaces to variation in these inputs constrain uncertainty in model predictions and are presented. Although optical earth observation analysis can provide fractional vegetation cover, cloud cover and semi-random weather patterns can hinder data acquisition in Northern Europe. A Spring and Autumn cloud cover analysis is carried out over seven UK sites close to agricultural districts, using historic satellite image metadata, climate modelling and historic ground weather observations. Results are assessed in terms of probability of acquisition probability and implications
Effective irrigation management is key to obtaining the most crop production per unit of water applied and increasing production in the face of competing demands on water resources. Management methods have included calculating crop water needs based on weather station measurements, calculating soil ...
Kimball, Keith R.; Middlebrooks, E. Joe
What Quality Management in Utah Mountain Streams: Several years of thorough monitoring of water quality parameters in Little Cottonwood Creek in Salt Lake County, Utah, measured the natural levels of the major water constituents, spotted significant (largely nonpoint) pollution sources, identified the pollutants deserving primary attention, and suggested the approaches to land and water management for pollution co...
E. BEILICCI; R. BEILICCI
Water management system include all activities and works which providing the administration of public domain of water, with local / national interest, and qualitative, quantitative and sustainable management of water resources. Hydrotechnical arrangements, consisting of a set of hydraulic structures, produce both a favorable and unfavorable influences on environment. Their different constructive and exploitation solutions exercise a significantly impact on the environment. Therefore the advan...
World Bank Group
This note provides guidance for cities in developing countries for managing the urban water cycle in a sustainable manner by using an Integrated Urban Water Management (IUWM) approach. After a brief introduction to the concept of IUWM, this note profiles the different IUWM approaches applied in three types of cities: a water-scarce, fast-developing city (Windhoek, Namibia), an expanding city ...
Aldaya, Maite; Hoekstra, Arjen
In a context where water resources are unevenly distributed and, in some regions precipitation and drought conditions are increasing, enhanced water management is a major challenge to final consumers, businesses, water resource users, water managers and policymakers in general. By linking a large range of sectors and issues, virtual water trade and water footprint analyses provide an appropriate framework to find potential solutions and contribute to a better management of water resources. The water footprint is an indicator of freshwater use that looks not only at direct water use of a consumer or producer, but also at the indirect water use. The water footprint of a product is the volume of freshwater used to produce the product, measured over the full supply chain. It is a multi-dimensional indicator, showing water consumption volumes by source and polluted volumes by type of pollution; all components of a total water footprint are specified geographically and temporally. The water footprint breaks down into three components: the blue (volume of freshwater evaporated from surface or groundwater systems), green (water volume evaporated from rainwater stored in the soil as soil moisture) and grey water footprint (the volume of polluted water associated with the production of goods and services). Closely linked to the concept of water footprint is that of virtual water trade, which represents the amount of water embedded in traded products. Many nations save domestic water resources by importing water-intensive products and exporting commodities that are less water intensive. National water saving through the import of a product can imply saving water at a global level if the flow is from sites with high to sites with low water productivity. Virtual water trade between nations and even continents could thus be used as an instrument to improve global water use efficiency and to achieve water security in water-poor regions of the world. The virtual water trade
Zhuo, Lu; Han, Dawei
Soil moisture has been widely recognized as a key element in hydrological processes and plays a significant role in hydrological modelling, which is now possible to be measured by satellite techniques. However most previous papers only discussed on their evaluations against point-based ground measurements and analyzed only one orbit (i.e. ascending overpass). It is known that the global Level-3 soil moisture dataset generated from the Soil Moisture and Ocean Salinity (SMOS) observations has been released lately by the Barcelona Expert Center. In order to solve the aforementioned problems, this study particularly focused on catchment scale assessment, where the Soil Moisture Deficit (SMD) derived from the three-layer Xinanjiang (XAJ) model was employed as a hydrological benchmark for all the evaluations and comparisons. Moreover both ascending and descending overpasses were analyzed for a more comprehensive comparison. It was interesting to find that the SMOS soil moisture accuracy was not improving with time as we would have expected. Moreover none of the overpasses provided reliable soil moisture estimates in the frozen season, especially for the ascending orbit. When frozen periods were removed, both overpasses presented significant improvement (i.e. the correlations increased from r = -0.53 to r = -0.65 and from r = -0.62 to r = -0.70, for ascending and descending overpasses respectively). Furthermore it was noted that SMOS retrievals from descending overpass were consistently about 11.7% by volume wetter than ascending retrievals. The overall evaluation demonstrated that descending orbit surpassed the ascending orbit, which contradicted the results found in many studies. Finally, the potential reasons were discussed.
Full Text Available Seven species of crayfish are present in Swiss waters: three native ones (Astacus astacus, Austropotamobius pallipes, Austropotamobius torrentium and four exotic ones (Astacus leptodactylus, Orconectes limosus, Pacifastacus leniusculus, Procambarus clarkii. The occurrence of each species is known and distribution maps have been drawn at national level. Many of the non-native populations have been identified as carriers of the crayfish plague, acting as a vector for Aphanomyces astaci. Crayfish are regulated by the Swiss Fisheries Legislation. The catching of the native species is allowed but the effective fishing pressure is low. The non-native species are considered as undesirable. For that reason importation, introduction and transportation of live specimens are forbidden with the exception of Cherax sp. which may be kept in cool boxes without any contact with water until consumption. A national management plan has been developed by the Federal Office for the Environment. It aims at increasing protective measures for the native species and enhancing population control for the non-native ones. The elimination measures are targeted on the most problematic species Pacifastacus leniusculus and Procambarus clarkii.
P. Gonzales; N. K. Ajami
Traditional urban water supply portfolios have proven to be unsustainable under the uncertainties associated with growth and long-term climate variability. Introducing alternative water supplies such as recycled water, captured runoff, desalination, as well as demand management strategies such as conservation and efficiency measures, has been widely proposed to address the long-term sustainability of urban water resources. Collaborative ef...
Molina-Navarro, Euginio; Trolle, Dennis; Martinez-Pérez, Silvia;
Water scarcity and water pollution constitute a big challenge for water managers in the Mediterranean region today and will exacerbate in a projected future warmer world, making a holistic approach for water resources management at the catchment scale essential. We expanded the Soil and Water...... recreational purposes. Simulations showed a noticeable impact of climate change in the river flow regime and consequently the water level of the limno-reservoir, especially during summer, complicating the fulfillment of its purposes. All the scenarios predicted a deterioration of trophic conditions in the...... Pareja Limno-reservoir and a switch from an oligo-mesotrophic to a mesotrophic state, which may threaten the maintenance of a favourable water quality. Our model framework may help water managers to assess and manage how climate change affects aquatic ecosystems....
Hanson, Randall T.; Schmid, Wolfgang
Disruption of water availability leads to food scarcity and loss of economic opportunity. Development of effective water-resource policies and management strategies could provide resiliance to local economies in the face of water disruptions such as drought, flood, and climate change. To accomplish this, a detailed understanding of human water use and natural water resource availability is needed. A hydrologic model is a computer software system that simulates the movement and use of water in a geographic area. It takes into account all components of the water cycle--“One Water”--and helps estimate water budgets for groundwater, surface water, and landscape features. The U.S. Geological Survey MODFLOW One-Water Integrated Hydrologic Model (MODFLOWOWHM) software and scientific methods can provide water managers and political leaders with hydrologic information they need to help ensure water security and economic resilience.
Land drainage has been central to the development of North America since colonial times. Increasingly, agricultural drainage is being targeted as a conduit for pollution, particularly nutrient pollution. The export of agricultural drainage water and associated pollutants to surface water can be mana...
Lyon, S. W.; H. Laudon; Seibert, Jan; Morth, M.; D. Tetzlaff; K. H. Bishop
Catchment-scale transit times for water are increasingly being recognized as an important control on geochemical processes. In this study, snowmelt water mean transit times (MTTs) were estimated for the 15 Krycklan research catchments in northern boreal Sweden. The snowmelt water MTTs were assumed to be representative of the catchment-scale hydrologic response during the spring thaw period and, as such, may be considered to be a component of the catchment's overall MTT. These snowmelt water M...
This book introduces biological waste water treatment with basic theory and activated sludge process, which includes chemical reaction engineering with reaction velocity and mass balance, an effector, characteristic of water treatment effector and biological waste water disposal such as flow pattern and tracer test. This is biological theory of steady on waste water treatment, design and management.
Water is a necessary resource for coal fired power plant and waste water is generated. The efficient management of water and waste water systems becomes an important operational environmental factor. This paper describes the development and implementation of a ten year water and waste water management strategy for the Latrobe Valley Group of brown coal fired power stations in Victoria. In early 1991, a team was put together of representatives from each power site to develop the strategy entitled 'SECV Latrobe Valley Water and Wastewater Management Strategy'. The strategy was developed with extensive public consultation, which was a factor in protracting the process such that the final document was not promulgated until late 1992. However, the final comprehensive document endorsed and agreed by management, has since attracted favourable comment as a model of its type. (author). 2 figs
Full Text Available To move towards sustainable development, the mining industry needs to identify better mine water management practices for reducing raw water use, increasing water use efficiency, and eliminating environmental impacts in a precondition of securing mining production. However, the selection of optimal mine water management practices is technically challenging due to the lack of scientific tools to comprehensively evaluate management options against a set of conflicting criteria. This work has provided a solution to aid the identification of more sustainable mine water management practices. The solution includes a conceptual framework for forming a decision hierarchy; an evaluation method for assessing mine water management practices; and a sensitivity analysis in view of different preferences of stakeholders or managers. The solution is applied to a case study of the evaluation of sustainable water management practices in 16 mines located in the Bowen Basin in Queensland, Australia. The evaluation results illustrate the usefulness of the proposed solution. A sensitivity analysis is performed according to preference weights of stakeholders or managers. Some measures are provided for assessing sensitivity of strategy ranking outcomes if the weight of an indicator changes. Finally, some advice is given to improve the mine water management in some mines.
Mikkelsen, Peter Steen; Viklander, M.; Linde, Jens Jørgen; Malmqvist, P.A.
Best Management Practices (BMPs) for control of stormwater runoff include structural elemts (structural BMPs) that can be applied on the local scale (e.g. infiltration), the drainage catchment scale (e.g. ponds and treatment, or wetlands) and the receiving water scale (e.g. retrofitting of river ...... review of recent experiences with selected stormwater BMPs in Denmark and Sweden is presented and discussed with respect to the current issues related to legislation and the forces driving future development in stormwater management.......Best Management Practices (BMPs) for control of stormwater runoff include structural elemts (structural BMPs) that can be applied on the local scale (e.g. infiltration), the drainage catchment scale (e.g. ponds and treatment, or wetlands) and the receiving water scale (e.g. retrofitting of river...... reaches), and non-structural BMPs, such as controls of chemicals or building materials, and street sweeping. The available knowledge of stormwater BMPs performance in pollution control is inconsistent and the effect of various BMPs on receiving water quality is either poorly understood, or not known. A...
Carter, Layne; Pruitt, Jennifer; Brown, Christopher A.; Schaezler, Ryan; Bankers, Lyndsey
Water management on ISS is responsible for the provision of water to the crew for drinking water, food preparation, and hygiene, to the Oxygen Generation System (OGS) for oxygen production via electrolysis, to the Waste & Hygiene Compartment (WHC) for flush water, and for experiments on ISS. This paper summarizes water management activities on the ISS US Segment, and provides a status of the performance and issues related to the operation of the Water Processor Assembly (WPA) and Urine Processor Assembly (UPA). This paper summarizes the on-orbit status as of May 2015 and describes the technical challenges encountered and lessons learned over the past two years.
Carter, Layne; Pruitt, Jennifer; Brown, Christopher A.; Bazley, Jesse; Gazda, Daniel; Schaezler, Ryan; Bankers, Lyndsey
Water management on ISS is responsible for the provision of water to the crew for drinking water, food preparation, and hygiene, to the Oxygen Generation System (OGS) for oxygen production via electrolysis, to the Waste & Hygiene Compartment (WHC) for flush water, and for experiments on ISS. This paper summarizes water management activities on the ISS US Segment and provides a status of the performance and issues related to the operation of the Water Processor Assembly (WPA) and Urine Processor Assembly (UPA). This paper summarizes the on-orbit status as of May 2016 and describes the technical challenges encountered and lessons learned over the past year.
van Griensven, Ann; Haest, Pieter Jan; Broekx, Steven; Seuntjens, Piet; Campling, Paul; Ducos, Geraldine; Blaha, Ludek; Slobodnik, Jaroslav
The European Union (EU) adopted the Water Framework Directive (WFD) in 2000 ensuring that all aquatic ecosystems meet ‘good status' by 2015. However, it is a major challenge for river basin managers to meet this requirement in river basins with a high population density as well as intensive agricultural and industrial activities. The EU financed AQUAREHAB project (FP7) specifically examines the ecological and economic impact of innovative rehabilitation technologies for multi-pressured degraded water bodies. For this purpose, a generic collaborative management tool ‘REACH-ER' is being developed that can be used by stakeholders, citizens and water managers to evaluate the ecological and economical effects of different remedial actions on waterbodies. The tool is built using databases from large scale models simulating the hydrological dynamics of the river basing and sub-basins, the costs of the measures and the effectiveness of the measures in terms of ecological impact. Knowledge rules are used to describe the relationships between these data in order to compute the flux concentrations or to compute the effectiveness of measures. The management tool specifically addresses nitrate pollution and pollution by organic micropollutants. Detailed models are also used to predict the effectiveness of site remedial technologies using readily available global data. Rules describing ecological impacts are derived from ecotoxicological data for (mixtures of) specific contaminants (msPAF) and ecological indices relating effects to the presence of certain contaminants. Rules describing the cost-effectiveness of measures are derived from linear programming models identifying the least-cost combination of abatement measures to satisfy multi-pollutant reduction targets and from multi-criteria analysis.
Environmental Protection Agency, Washington, DC. Office of Public Affairs.
This pamphlet addresses the problems associated with residuals and water quality especially as it relates to the National Water Pollution Control Program. The types of residuals and appropriate management systems are discussed. Additionally, one section is devoted to the role of citizen participation in developing management programs. (CS)
Algeria aspires to protect its water resources and to provide a sustainable answer to water supply and management issues by carrying out a national water plan. This program is in line with all projects the Algerian Government is implementing to improve its water sector performance. The water strategy focuses on desalination for the coastal cities, medium-sized dams to irrigate the inland mountains and high plateau, and ambitious water transfer projects interconnecting Algeria\\'s 65 dams to bring water to water scarce parts of the country. Waste water treatment and water reclamation technologies are also highly sought after. The main objective of the country\\'s water policy consists on providing sufficient potable water for the population supply. This objective is undertaken by increasing the water resources and availability. © 2012 Desalination Publications. All rights reserved.
One of the most pressing national and global issues is the availability of freshwater due to global climate change, energy scarcity issues and the increase in world population and accompanying economic growth. Estimates of water supplies and flows through the world's hydrologic c...
Tychon, Bernard; Balaghi, Riad; Jlibene, Mohammed
Water availability for agricultural activities will decrease in the twenty-first century. As a consequence, agricultural water management will have to improve in order to meet two challenges: satisfy the needs of an increasing world population; and alleviate the climate change impacts. One way to improve agricultural water management consists of including the ‘risk’ notion as much as possible at the different decision levels of: farmers, farmer corporations and states or associations of st...
Katherine A. Daniell; Rinaudo, Jean-Daniel; Chan, Noel; Nauges, Céline; Grafton, Quentin
International audience Understanding and managing water in the urban context is of vital global importance. Over half the world’s population now lives in urban environments (United Nations 2013) and the percentage is set to increase over coming decades. Quality urban living, like life anywhere, requires adequate quantities and qualities of water to support a range of social well-being, economic development, and environmental health. Managing water in cities, along with their linked energy,...
US Fish and Wildlife Service, Department of the Interior — Content includes 2008 weather summary, 2008 water management summaries, 2009 water availability forecast, and 2009 water management strategy.
US Fish and Wildlife Service, Department of the Interior — Content includes 2005 weather summary, 2005 water management summaries, 2006 water availability forecast, and 2006 water management strategy.
US Fish and Wildlife Service, Department of the Interior — Content includes 2007 weather summary, 2007 water management summaries, 2008 water availability forecast, and 2008 water management strategy.
US Fish and Wildlife Service, Department of the Interior — Content includes 2006 weather summary, 2006 water management summaries, 2007 water availability forecast, and 2007 water management strategy.
US Fish and Wildlife Service, Department of the Interior — Content includes 2003 weather summar, 2003 water management summaries, 2004 water availability forecast, and 2004 water management strategy.
Properly managed pasture water not only provides high-quality water which promotes healthy and productive livestock, but also contributes to maintaining water quality downstream. Riparian (streamside) areas serve as a transition between upland pastures and waterways. In other words, they link pastur...
Subsurface tile drainage is an essential water management practice on many highly productive fields in the Midwest. However, nitrate carried in drainage water can lead to local water quality problems and contribute to hypoxia in the Gulf of Mexico, so strategies are needed to reduce the nitrate load...
van Loenen, A.; van Dijk, M.; van Verseveld, W.; Berger, H.
Most of the Dutch large rivers, canals and lakes are controlled by the Dutch water authorities. The main reasons concern safety, navigation and fresh water supply. Historically the separate water bodies have been controlled locally. For optimizating management of these water systems an integrated approach was required. Presented is a platform which integrates data from all control objects for monitoring and control purposes. The Operational Management System for Regulated Water Systems (IWP) is an implementation of Delft-FEWS which supports operational control of water systems and actively gives advice. One of the main characteristics of IWP is that is real-time collects, transforms and presents different types of data, which all add to the operational water management. Next to that, hydrodynamic models and intelligent decision support tools are added to support the water managers during their daily control activities. An important advantage of IWP is that it uses the Delft-FEWS framework, therefore processes like central data collection, transformations, data processing and presentation are simply configured. At all control locations the same information is readily available. The operational water management itself gains from this information, but it can also contribute to cost efficiency (no unnecessary pumping), better use of available storage and advise during (water polution) calamities.
For many years, water resources management in Vietnam was concentrated on activities ensuring the available freshwater for agricultural production, including flood control. With the increase of water demands and the emergence of new water usages since the late 1980s, this has subsequently changed. During the past two decades, and within the context of a broad economic transition process, the water sector has undergone a series of reforms, including various attempts to integrate environmental ...
The course, Decision Support Techniques for Integrated Water Resources Management, is designed mainly for technical managers and staff of water resources management agencies at the international, national, regional, and local water board level, as well as consultants in other professions working in or interested in the field of water resources development, planning, and operation. It will be held in Wageningen, The Netherlands, June 10-15, 1991.The course objective is to promote better understanding and dissemination of techniques to be applied in “real-world” integrated water resources management. The course offers an introduction to the concepts of decision modeling, plus ample case studies to demonstrate their applicability. It covers decision theory, operations research and simulation methods, as well as certain aspects of law and psychology. Selected multiple objective techniques will be presented, followed by an overview of recent trends in the field. Computer-based techniques will be demonstrated.
Full Text Available To achieve an appropriate management strategy was monitored surface water quality in the county of Prahova. In this regard were determinate major physical and chemical indicators: pH, BOD5, COD, nitrates, nitrites, and suspended solids. Depending on the value of the data obtained was identified water quality classes corresponding to each surface water body studied. The correlation values obtained with the best solutions for water service and maintenance of water courses is a management plan for surface water in the county of Prahova. The novelty of the paper consists of study of water resources in the county and not in the Basin as is done at present by the Romanian Waters National Administration
In this paper the authors present an approach to the development of an accident management plan for adding water to a degraded core. Under certain degraded core conditions, adding water may lead to enhanced hydrogen production, changes in core geometry that would complicate recovery, steam explosions, or recriticality of the reactor core if unborated water is used. Therefore, a primary requisite for the development of an accident management plan for adding water to a degraded core is to ensure that undesirable consequences of water addition are understood so that: (1) their effects can be minimized and an accident can be terminated at the earliest possible stage, and (2) plant personnel can be better prepared to deal with plant responses that appear contrary to desired outcomes when water is added during a core degradation transient. The approach presented here addresses these concerns in the development of an accident management plan
Booman, Gisel Carolina; Calandroni, Mirta; Laterra, Pedro; Cabria, Fabián; Iribarne, Oscar; Vázquez, Pablo
Wetland loss is a frequent concern for the environmental management of rural landscapes, but poor disentanglement between climatic and land management causes frequently constrains both proper diagnoses and planning. The aim of this study is to address areal changes induced by non-climatic factors on lentic water bodies (LWB) within an agricultural basin of the Argentinean Pampas, and the human activities that might be involved. The LWB of the Mar Chiquita basin (Buenos Aires province, Argentina) were mapped using Landsat images from 1998-2008 and then corrected for precipitation variability by considering the regional hydrological status on each date. LWB areal changes were statistically and spatially analyzed in relation to land use changes, channelization of streams, and drainage of small SWB in the catchment areas. We found that 12 % of the total LWB in the basin had changed (P < 0.05) due to non-climatic causes. During the evaluated decade, 30 % of the LWB that changed size had decreased while 70 % showed steady increases in area. The number of altered LWB within watersheds lineally increased or decreased according to the proportion of grasslands replaced by sown pastures, or the proportion of sown pastures replaced by crop fields, respectively. Drainage and channelization do not appear to be related to the alteration of LWB; however some of these hydrologic modifications may predate 1998, and thus earlier effects cannot be discarded. This study shows that large-scale changes in land cover (e.g., grasslands reduction) can cause a noticeable loss of hydrologic regulation at the catchment scale within a decade. PMID:22990683
Klatt, S.; Butterbach-Bahl, K.; Kiese, R.; Haas, E.; Kraus, D.; Molina-Herrera, S. W.; Kraft, P.
The continuous growth of the human population demands an equally growing supply for fresh water and food. As a result, available land for efficient agriculture is constantly diminishing which forces farmers to cultivate inferior croplands and intensify agricultural practices, e.g., increase the use of synthetic fertilizers. This intensification of marginal areas in particular will cause a dangerous rise in nitrate discharge into open waters or even drinking water resources. In order to reduce the amount of nitrate lost by surface runoff or lateral subsurface transport, bufferstrips have proved to be a valuable means. Current laws, however, promote rather static designs (i.e., width and usage) even though a multitude of factors, e.g., soil type, slope, vegetation and the nearby agricultural management, determines its effectiveness. We propose a spatially explicit modeling approach enabling to assess the effects of those factors on nitrate discharge from arable lands using the fully distributed hydrology model CMF coupled to the complex biogeochemical model LandscapeDNDC. Such a modeling scheme allows to observe the displacement of dissolved nutrients in both vertical and horizontal directions and serves to estimate both their uptake by the vegetated bufferstrip and loss to the environment. First results indicate a significant reduction of nitrate loss in the presence of a bufferstrip (2.5 m). We show effects induced by various buffer strip widths and plant cover on the nitrate retention.
At present, Beijing's water resources are insufficient and will become the limiting factor for sustainable development for the city in the near future. Although efforts have been made to control pollution, water quality degradation has occurred in some of the important surface water supplies, aggravating the water resource shortage. At present, approximately three quarters of the city's wastewater is discharged untreated into the urban river system, resulting in serious pollution and negatively influencing the urban landscape and quality of daily life. To counteract these measures, the city has implemented a comprehensive "Water Quality Management Plan" for the region, encompassing water pollution control, prevention of water body degradation, and improved water quality.The construction of municipal wastewater treatment plants is recognised as fundamental to controlling water pollution, and full secondary treatment is planned to be in place by the year 2015. Significant work is also required to expand the service area of the municipal sewage system and to upgrade and renovate the older sewer systems. The limitation on available water resources has also seen the emphasis shift to low water using industries and improved water conservation. Whilst industrial output has increased steadily over the past 10-15 years at around 10% per annum, industrial water usage has remained relatively constant. Part of the city's water quality management plan has been to introduce a strict discharge permit system, encouraging many industries to install on-site treatment facilities.
The 1998 South African water reform is a good example of an attempt to democratize water resource management. It created new decentralised water management bodies and openly called for the participation of all individual water users. Yet, if the reform and discourses of the time unequivocally declared the intentions of the South African water law, the conditions surrounding the implementation of the reform left many grey areas in the materialisation of active user participation objectives, al...
Dumitru Florin FRONE
Full Text Available As we try to point out again in this paper, water is one of the most important and scarce environmental resources, with some particular characteristics that raise serious challenges for a good management and sustainable development. First we define the concept of Water Demand Management, as a part of a Sustainable Water Management, along with stating some of its main recent political and economic issues and objectives in the European Union. Here, agriculture has been identified as a major sustainable water management issue in the implementation of the Water Framework Directive (WFD. The scarcity of the water resource has become a concern only in more recent studies, reflecting the shift from the engineering perspective of increasing supply to satisfy demand, to the economic perspective of also managing demand through price to efficiently allocate the existing quantity of water supply. Therefore, as a first conclusion, economists should try to find the best theoretical and practical approaches to deal with these challenges, expressing awareness on the fact that water is no longer a free public good, but a rare and valuable economic good.
Brüschweiler, Sabine; Höggel, Udo; Kläy, Andreas
Due to their biodiversity, forests generate a range of products and services that are of economic, social or cultural value to human beings. Natural resource management provisions should ensure the creation and maintenance of these goods and services in the long term. However, unsustainable management practices of forests do not only generate short-term benefits but also considerable costs for society. Payment by the beneficiaries of the services would enable us to internalise external costs ...
until recently. This paper sets the stage with respect to perspective and management options related to implementation of water reuse. Water treatment has to be interpreted as the means by which to purify the water from any degree of impurity to any degree of purity that fits the desired use, including......The water resource is under increasing pressure, both from the increase in population and from the wish to improve the living standards of the individual. Water scarcity is defined as the situation where demand is greater than the resource. Water scarcity has two distinctly different dimensions......: water availability and water applicability. The availability is a question of quantitative demand relative to resource. The applicability is a question of quality suitability for the intended use of the water. There is a significant difference in this regard with respect to rural versus urban use of...