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Water Management (water + management)
Kinds of Water Management Terms modified by Water Management Selected AbstractsEFFECTS OF INCREASED DELTA EXPORTS ON SACRAMENTO VALLEY'S ECONOMY AND WATER MANAGEMENT,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 6 2003Stacy K. Tanaka ABSTRACT: Exports from the Sacramento-San Joaquin Delta are an important source of water for Central Valley and Southern California users. The purpose of this paper is to estimate and analyze the effects increased exports to south of Delta users would have on the Sacramento Valley economy and water management if water were managed and reallocated for purely economic benefits, as if there were an ideal Sacramento Valley water market. Current Delta exports of 6,190 thousand acre-feet per year were increased incrementally to maximum export pumping plant capacities. Initial increases in Delta exports did not increase regional water scarcity, but decreased surplus Delta flows. Further export increases raised agricultural scarcity. Urban users suffer increased scarcity only for exports exceeding 10,393 taf/yr. Expanding exports raises the economic value of expanding key facilities (such as Engle bright Lake and South Folsom Canal) and the opportunity costs of environmental requirements. The study illustrates the physical and economic capacity of the Sacramento Valley to further increase exports of water to drier parts of the state, even within significant environmental flow restrictions. More generally, the results illustrate the physical capacity for greater economic benefits and flexibility in water management within environmental constraints, given institutional capability to reoperate or reallocate water resources, as implied by water markets. [source] Intra- and interlaboratory calibration of the DR CALUX® bioassay for the analysis of dioxins and dioxin-like chemicals in sedimentsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2004Harrie T. Besselink Abstract In the Fourth National Policy Document on Water Management in the Netherlands [1], it is defined that in 2003, in addition to the assessment of chemical substances, special guidelines for the assessment of dredged material should be recorded. The assessment of dredged material is based on integrated chemical and biological effect measurements. Among others, the DR CALUX® (dioxin responsive,chemically activated luciferase expression) bioassay has tentatively been recommended for inclusion in the dredged material assessment. To ensure the reliability of this bioassay, an intra- and interlaboratory validation study, or ring test, was performed, organized by the Dutch National Institute for Coastal and Marine Management (RIKZ) in cooperation with BioDetection Systems BV (BDS). The intralaboratory repeatability and reproducibility and the limit of detection (LOD) and quantification (LOQ) of the DR CALUX bioassay were determined by analyzing sediment extracts and dimethyl sulfoxide (DMSO) blanks. The highest observed repeatability was found to be 24.1%, whereas the highest observed reproducibility was calculated to be 19.9%. Based on the obtained results, the LOD and LOQ to be applied for the bioassay are 0.3 and 1.0 pM, respectively. The interlaboratory calibration study was divided into three phases, starting with analyzing pure chemicals. During the second phase, sediment extracts were analyzed, whereas in the third phase, whole sediments had to be extracted, cleaned, and analyzed. The average interlaboratory repeatability increased from 14.6% for the analysis of pure compound to 26.1% for the analysis of whole matrix. A similar increase in reproducibility with increasing complexity of handlings was observed with the interlaboratory reproducibility of 6.5% for pure compound and 27.9% for whole matrix. The results of this study are intended as a starting point for implementing the integrated chemical,biological assessment strategy and for systematic monitoring of dredged materials and related materials in the coming years. [source] Effects of atmospheric circulation on ice conditions in the southern Baltic coastal lagoonsINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 13 2001Józef Piotr Girjatowicz Abstract Relationships between atmospheric circulation patterns and ice conditions in the southern Baltic coastal lagoons were explored. Ice data consisted of number of ice days (L) and duration of ice season (S) in the Szczecin Lagoon (off Karnin), the Puck Bay (off Puck) and the Vistula Lagoon (off Krasnoflotskoye) from 1950/1951 to 1989/1990. Atmospheric circulation patterns for the period studied were extracted from Lity,ski's ,Calendar of atmospheric circulation types' developed at the Institute of Meteorology and Water Management (IMWM). A circulation pattern was identified by three numerical parameters: the zonal circulation index, the meridional circulation index, both pertaining to a zone delimited by coordinates 40,60°N, 0,35°E, and the surface pressure index for Warsaw. The number of days with individual atmospheric circulation patterns occurring from October to March was calculated. Subsequently, the selected patterns were combined by wind direction sectors and several month-long periods that most closely correlated with ice conditions. The highest linear correlation coefficients (r>0.8) were obtained for the relationship between the number of days with winds from the east from December to February and December to March and the winter number of ice days (L). Somewhat higher were multiple correlation coefficients with winds from the east and west as circulation type predictors. Slightly lower correlation coefficients for the sectors and circulation periods mentioned were obtained for the duration of the ice season (S), although some of the coefficients were significant even at the probability level of ,=0.01. Higher correlation coefficients were obtained for correlations involving ,cold' circulation patterns (sector NE+E+SE winds) and ice conditions than for those involving ,warm' patterns (sector SW+W+NW). Copyright © 2001 Royal Meteorological Society [source] Book Reviews: Integrated Water Resources Management in Practice: Better Water Management for DevelopmentJOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 4 2010Richard H. McCuen No abstract is available for this article. [source] Integrated Water Resources Management in Practice: Better Water Management for Development , Edited by Roberto Lenton and Mike MullerNATURAL RESOURCES FORUM, Issue 4 2009Mirja Kattelus No abstract is available for this article. [source] Politics, Plurality and Problemsheds: A Strategic Approach for Reform of Agricultural Water Resources ManagementDEVELOPMENT POLICY REVIEW, Issue 6 2007Peter P. Mollinga Starting from the assessment that past efforts at reform in agricultural water management in developing countries have achieved very little, this article argues that a fundamental change is required in the approach to policy and institutional transformation if the present deadlock in the internalisation of ecological sustainability, human development/poverty alleviation and democratic governance into the ,core business' of water bureaucracies is to be overcome. ,Social engineering' approaches need to be replaced by ,strategic action' approaches that acknowledge the inherently political character and the plurality of actors, institutions and objectives of water management , a perspective operationalised here around the notions of ,problemshed' and ,issue network'. [source] Benthic macroinvertebrates in Swedish streams: community structure, taxon richness, and environmental relationsECOGRAPHY, Issue 3 2003Leonard Sandin Spatial scale, e.g. from the stream channel, riparian zone, and catchment to the regional and global scale is currently an important topic in running water management and bioassessment. An increased knowledge of how the biota is affected by human alterations and management measures taken at different spatial scales is critical for improving the ecological quality of running waters. However, more knowledge is needed to better understand the relationship between environmental factors at different spatial scales, assemblage structure and taxon richness of running water organisms. In this study, benthic macroinvertebrate data from 628 randomly selected streams were analysed for geographical and environmental relationships. The dataset also included 100 environmental variables, from local measures such as in-stream substratum and vegetation type, catchment vegetation and land-use, and regional variables such as latitude and longitude. Cluster analysis of the macroinvertebrate data showed a continuous gradient in taxonomic composition among the cluster groups from north to south. Both locally measured variables (e.g. water chemistry, substratum composition) and regional factors (e.g. latitude, longitude, and an ecoregional delineation) were important for explaining the variation in assemblage structure and taxon richness for stream benthic macroinvertebrates. This result is of importance when planning conservation and management measurements, implementing large-scale biomonitoring programs, and predicting how human alterations (e.g. global warming) will affect running water ecosystems. [source] Using framing parameters to improve handling of uncertainties in water management practiceENVIRONMENTAL POLICY AND GOVERNANCE, Issue 2 2010Nicola Isendahl Abstract Management of water resources is afflicted with uncertainties. Nowadays it is facing more and new uncertainties since the pace and dimension of changes (e.g. climatic, demographic) are accelerating and are likely to increase even more in the future. Hence it is crucial to find pragmatic ways to deal with these uncertainties in water management. We argue for an analytical yet pragmatic approach to enable decision-makers to deal with uncertainties in a more explicit and systematic way and allow for better informed decisions. Our approach is based on the concept of framing, referring to the different ways in which people make sense of the world and of the uncertainties. We apply recently developed parameters of the framing of uncertainty in two sub-basins of the Rhine, the Dutch Kromme Rijn and the German Wupper. We present and discuss the results of a series of stakeholder interactions in the two basins aimed at developing strategies for improving dealing with uncertainties. The strategies are amended and synthesized in a check-list based on the uncertainty framing parameters as a hands-on tool for systematically identifying improvement options when dealing with uncertainty in water management practice. We conclude with suggestions for testing the developed check-list as a tool for decision aid in water management practice. Copyright © 2010 John Wiley & Sons, Ltd and ERP Environment. [source] Regional development, nature production and the techno-bureaucratic shortcut: the Douro River catchment in PortugalENVIRONMENTAL POLICY AND GOVERNANCE, Issue 6 2008Antonio A. R. Ioris Abstract The introduction of the Water Framework Directive in Europe represents a unique opportunity to promote more inclusive strategies for the long-term preservation of (socionatural) water systems. However, the analysis of the Portuguese experience, using the River Douro as a case study, reveals still considerable shortcomings in the assessment of problems and the formulation of solutions. Instead of promoting a meaningful dialogue between social groups and spatial areas, there is a systematic attempt to conform to legal requisites by taking a ,techno-bureaucratic' shortcut that largely reproduces the distortions of previous regulatory approaches. Decisions on water management are part of political disputes about regional development and state reform, such as in relation to the provision of water and electricity by public utilities. Nonetheless, these broader issues have been kept tacitly away from the WFD agenda, which has been concentrated on adjusting established procedures to the (formal) requirements of the new regulation. Copyright © 2008 John Wiley & Sons, Ltd and ERP Environment. [source] Criteria for the assessment of processes for sustainable river basin management and their congruence with the EU Water Framework DirectiveENVIRONMENTAL POLICY AND GOVERNANCE, Issue 4 2008Beatrice Hedelin Abstract In order to manage the increasing pressure on the world's water resources, new planning methodologies/processes for sustainable river basin management are currently being developed. For such processes to work well, however, the legal context must allow, or support, such processes. In this study, a set of criteria relating to methodologies/processes for sustainable water management is used to assess the EU Water Framework Directive (WFD). The study suggests that the WFD erects few formal barriers to good planning practices. However, planning processes will need to be adapted to compensate for the weak legal support in a number of important areas, namely the use of knowledge from beyond the natural sciences, the use of methodologies for the explicit handling of values and the use of procedures for democratic participation. In so doing the issues identified here provide a basis for systematic thinking about how to design the necessary planning processes. Copyright © 2008 John Wiley & Sons, Ltd and ERP Environment. [source] Multiple stressors and regime shifts in shallow aquatic ecosystems in antipodean landscapesFRESHWATER BIOLOGY, Issue 2010JENNY DAVIS Summary 1. Changes in land management (land use and land cover) and water management (including extraction of ground water and diversion of surface waters for irrigation) driven by increases in agricultural production and urban expansion (and fundamentally by population growth) have created multiple stressors on global freshwater ecosystems that we can no longer ignore. 2. The development and testing of conceptual ecological models that examine the impact of stressors on aquatic ecosystems, and recognise that responses may be nonlinear, is now essential for identifying critical processes and predicting changes, particularly the possibility of catastrophic regime shifts or ,ecological surprises'. 3. Models depicting gradual ecological change and three types of regime shift (simple thresholds, hysteresis and irreversible changes) were examined in the context of shallow inland aquatic ecosystems (wetlands, shallow lakes and temporary river pools) in southwestern Australia subject to multiple anthropogenic impacts (hydrological change, eutrophication, salinisation and acidification). 4. Changes in hydrological processes, particularly the balance between groundwater-dominated versus surface water-dominated inputs and a change from seasonal to permanent water regimes appeared to be the major drivers influencing ecological regime change and the impacts of eutrophication and acidification (in urban systems) and salinisation and acidification (in agricultural systems). 5. In the absence of hydrological change, urban wetlands undergoing eutrophication and agricultural wetlands experiencing salinisation appeared to fit threshold models. Models encompassing alternative regimes and hysteresis appeared to be applicable where a change from a seasonal to permanent hydrological regime had occurred. 6. Irreversible ecological change has potentially occurred in agricultural landscapes because the external economic driver, agricultural productivity, persists independently of the impact on aquatic ecosystems. 7. Thematic implications: multiple stressors can create multiple thresholds that may act in a hierarchical fashion in shallow, lentic systems. The resulting regime shifts may follow different models and trajectories of recovery. Challenges for ecosystem managers and researchers include determining how close a system may be to critical thresholds and which processes are essential to maintaining or restoring the system. This requires an understanding of both external drivers and internal ecosystem dynamics, and the interactions between them, at appropriate spatial and temporal scales. [source] Climatic influences and anthropogenic stressors: an integrated framework for streamflow management in Mediterranean-climate California, U.S.A.FRESHWATER BIOLOGY, Issue 2010THEODORE E. GRANTHAM Summary 1. In Mediterranean and other water-stressed climates, water management is critical to the conservation of freshwater ecosystems. To secure and maintain water allocations for the environment, integrated water management approaches are needed that consider ecosystem flow requirements, patterns of human water demands and the temporal and spatial dynamics of water availability. 2. Human settlements in Mediterranean climates have constructed water storage and conveyance projects at a scale and level of complexity far exceeding those in other, less seasonal climates. As a result, multiple ecological stressors associated with natural periods of flooding and drying are compounded by anthropogenic impacts resulting from water infrastructure development. 3. Despite substantial investments in freshwater ecosystem conservation, particularly in California, U.S.A., success has been limited because the scales at which river management and restoration are implemented are often discordant with the temporal and spatial scales at which ecosystem processes operate. Often, there is also strong social and political resistance to restricting water allocation to existing consumptive uses for environmental protection purposes. Furthermore, institutions rarely have the capacity to develop and implement integrated management programmes needed for freshwater ecosystem conservation. 4. We propose an integrated framework for streamflow management that explicitly considers the temporal and spatial dynamics of water supply and needs of both human and natural systems. This approach makes it possible to assess the effects of alternative management strategies to human water security and ecosystem conditions and facilitates integrated decision-making by water management institutions. 5. We illustrate the framework by applying a GIS-based hydrologic model in a Mediterranean-climate watershed in Sonoma County, California, U.S.A. The model is designed to assess the hydrologic impacts of multiple water users distributed throughout a stream network. We analyse the effects of vineyard water management on environmental flows to (i) evaluate streamflow impacts from small storage ponds designed to meet human water demands and reduce summer diversions, (ii) prioritise the placement of storage ponds to meet human water needs while optimising environmental flow benefits and (iii) examine the environmental and social consequences of flow management policies designed to regulate the timing of diversions to protect ecosystem functions. 6. Thematic implications: spatially explicit models that represent anthropogenic stressors (e.g. water diversions) and environmental flow needs are required to address persistent and growing threats to freshwater biodiversity. A coupled human,natural system approach to water management is particularly useful in Mediterranean climates, characterised by severe competition for water resources and high spatial and temporal variability in flow regimes. However, lessons learned from our analyses are applicable to other highly seasonal systems and those that are expected to have increased precipitation variability resulting from climate change. [source] Top-down control of phytoplankton: the role of time scale, lake depth and trophic stateFRESHWATER BIOLOGY, Issue 12 2002JÜrgen Benndorf SUMMARY 1.,One of the most controversial issues in biomanipulation research relates to the conditions required for top-down control to cascade down from piscivorous fish to phytoplankton. Numerous experiments have demonstrated that Phytoplankton biomass Top-Down Control (PTDC) occurs under the following conditions: (i) in short-term experiments, (ii) shallow lakes with macrophytes, and (iii) deep lakes of slightly eutrophic or mesotrophic state. Other experiments indicate that PTDC is unlikely in (iv) eutrophic or hypertrophic deep lakes unless severe light limitation occurs, and (v) all lakes characterised by extreme nutrient limitation (oligo to ultraoligotrophic lakes). 2.,Key factors responsible for PTDC under conditions (i) to (iii) are time scales preventing the development of slow-growing inedible phytoplankton (i), shallow depth allowing macrophytes to become dominant primary producers (ii), and biomanipulation-induced reduction of phosphorus (P) availability for phytoplankton (iii). 3.,Under conditions (iv) and (v), biomanipulation-induced reduction of P-availability might also occur but is insufficient to alter the epilimnetic P-content enough to initiate effective bottom-up control (P-limitation) of phytoplankton. In these cases, P-loading is much too high (iv) or P-content in the lake much too low (v) to initiate or enhance P-limitation of phytoplankton by a biomanipulation-induced reduction of P-availability. However, PTDC may exceptionally result under condition (iv) if high mixing depth and/or light attenuation cause severe light limitation of phytoplankton. 4.,Recognition of the five different conditions reconciles previous seemingly contradictory results from biomanipulation experiments and provides a sound basis for successful application of biomanipulation as a tool for water management. [source] The Empire Meets the New Deal: Interwar Encounters in Conservation and Regional PlanningGEOGRAPHICAL RESEARCH, Issue 4 2005J.M. POWELL Abstract British imperial and American experiences in conservation and planning are providing fresh interdisciplinary challenges for university teaching and research. The Roosevelt administration's ,New Deal' included government-sponsored interventions in soil erosion and water management and sophisticated regional development agendas. Reviewing samples of the latter areas of concern, this article explores the proposition that, although the British Empire was scarcely bereft of comparable interwar programmes and was becoming somewhat preoccupied with centrifugal tendencies, persistent porosity, exhausting struggles with postwar reconstruction, and comprehensive economic depression, New Deal evangelism was in fact variously anticipated, harnessed, challenged and ignored. A discussion of widely separated national and regional examples locates a layered interplay between uneven imperial and US pulsations, independent local manoeuvres, and critical inputs from key individual agents. The most important filters included the presence of comparatively robust bureaucratic infrastructures and the cultivation of international relationships by scientists and technologists. Encounters with convergent revisionism suggest cautionary leads for students, researchers and teachers alike. Reconstructions of selected contexts underline the presence of familiar posturing, opportunism, and astute patriotic deployment during the emergence of modern styles of globalization. [source] Isotope Methods for Management of Shared Aquifers in Northern AfricaGROUND WATER, Issue 5 2005Bill Wallin Access to fresh water is one of the major issues of northern and sub-Saharan Africa. The majority of the fresh water used for drinking and irrigation is obtained from large ground water basins where there is minor contemporary recharge and the aquifers cross national borders. These aquifers include the Nubian Aquifer System shared by Chad, Egypt, Libya, and Sudan; the Iullemeden Aquifer System, extending over Niger, Nigeria, Mali, Benin, and Algeria; and the Northwest Sahara Aquifer System shared by Algeria, Libya, and Tunisia. These resources are subject to increased exploitation and may be severely stressed if not managed properly as witnessed already by declining water levels. In order to make appropriate decisions for the sustainable management of these shared water resources, planners and managers in different countries need an improved knowledge base of hydrological information. Three technical cooperation projects related to aquifer systems will be implemented by the International Atomic Energy Agency, in collaboration with the United Nations Educational, Scientific and Cultural Organization and United Nations Development Programme/Global Environmental Facility. These projects focus on isotope hydrology studies to better quantify ground water recharge and dynamics. The multiple isotope approach combining commonly used isotopes 18O and 2H together with more recently developed techniques (chlorofluorocarbons, 36Cl, noble gases) will be applied to improve the conceptual model to study stratification and ground water flows. Moreover, the isotopes will be an important indicator of changes in the aquifer due to water abstraction, and therefore they will assist in the effort to establish a sustainable ground water management. [source] Highly Fluorinated Comb-Shaped Copolymers as Proton Exchange Membranes (PEMs): Improving PEM Properties Through Rational Design,ADVANCED FUNCTIONAL MATERIALS, Issue 14 2006B. Norsten Abstract A new class of comb-shaped polymers for use as a proton conducting membrane is presented. The polymer is designed to combine the beneficial physical, chemical, and structural attributes of fluorinated Nafion-like materials with higher-temperature, polyaromatic-based polymer backbones. The comb-shaped polymer unites a rigid, polyaromatic, hydrophobic backbone with lengthy hydrophilic polymer side chains; this combination affords direct control over the polymer nanostructure within the membrane and results in distinct microphase separation between the opposing domains. The microphase separation serves to compartmentalize water into the hydrophilic polymer side chain domains, resulting in effective membrane water management and excellent proton conductivities. [source] Wetlands with controlled drainage and sub-irrigation systems,modelling of the water balanceHYDROLOGICAL PROCESSES, Issue 14 2007Ottfried Dietrich Abstract Over the past centuries, the agricultural use of wetlands in Central Europe has required interference with the natural wetland water balance. Often this has consisted of drainage measures alone. In low-precipitation areas, it has also involved the operation of combined drainage and sub-irrigation systems. Model studies conducted as part of planning processes, or with a view to finding out the impact of changing climate conditions on the water balance of wetlands, must take these facts into account. For this reason, a water balance model has been devised for wetlands whose water balance is governed by water resources management systems. It is based on the WBalMo model system. Special modules were integrated into WBalMo to calculate the water balance of wetland areas (WABI module) and to regulate inflow partitioning within the wetland (REGINF module). When calculating the water balance, the WABI module takes into account precipitation and potential evapotranspiration, groundwater levels below surface, soil types, land-use classes, inflows via the running water system, and data for target water levels. It provides actual evapotranspiration, discharge into the running water system, and groundwater levels in the area. The example of the Spreewald, a major wetland area in north-eastern Germany, was used to design and test the WBalMo Spreewald model. The comparison of measured and calculated water balance parameters of the wetland area confirms the suitability of the model for water balance studies in wetlands with complex water resources management systems. The results reveal the strong influence of water management on the water balance of such areas. The model system has proved to be excellently suited for planning and carrying out water management measures aimed at the sustainable development of wetlands. Furthermore, scenario analyses can be used to assess the impact of global change on the water balance of wetlands. Copyright © 2006 John Wiley & Sons, Ltd. [source] Water fluxes at a fluctuating water table and groundwater contributions to wheat water use in the lower Yellow River flood plain, ChinaHYDROLOGICAL PROCESSES, Issue 6 2007Jianfeng Yang Abstract Capillary upflow from and deep percolation to a water table may be important in crop water supply in irrigated areas of the lower Yellow River flood plain, north China. These fluxes at the water table and the variations of the capillary upflow in relation to crop evapotranspiration need to be investigated to quantify the effect of a water table on soil water balance and to improve agricultural water management. A large weighing lysimeter was used to determine daily crop evapotranspiration, daily capillary upflow from and daily percolation to a fluctuating water table during a rotation period with wheat growing in a dry season and maize in a rainy season. The water table depth varied in the range 0·7,2·3 m during the maize growth period and 1·6,2·4 m during the wheat growth period. Experimental results showed that the capillary upflow and the percolation were significant components of the soil water balance. Three distinctly different phases for the water fluxes at the water table were observed through the rotation period: water downward period, the period of no or small water fluxes, and water upward period. It implied that the temporal pattern of these water fluxes at the water table was intimately associated with the temporal distribution of rainfall through the rotation period. An empirical equation was determined to estimate the capillary upflow in relation to wheat evapotranspiration and root zone soil water content for local irrigation scheduling. Coupled with the FAO-Penman,Monteith equation, the equation offers a fast and low cost solution to assess the effect of capillary upflow from a water table on wheat water use. Copyright © 2007 John Wiley & Sons, Ltd. [source] Water problems and hydrological research in the Yellow River and the Huai and Hai River basins of ChinaHYDROLOGICAL PROCESSES, Issue 12 2004Changming Liu Abstract This paper deals with hydrological research in regard to the water resources crisis in the vulnerable areas found in the northern part of China. This area includes three main river basins, namely the basins of the Yellow (Huang) River, the Hai River and the Huai River. Several water problems are becoming very severe. Among them, two are the most critical: the Yellow River has been drained dry in the main course of its lower reaches and along its major tributaries, and the groundwater table has rapidly declined in the floodplains of the three rivers' downstream areas. To counter the problems, particularly the critical issues mentioned above, hydrological research, which serves as the basis of water development and management, has been carried out in the last two decades. This paper addresses three basic scientific problems in North China, namely: (a) water consumption and the capacity for saving water; (b) the changes in hydrological processes and water resources caused by natural change and human activities; and (c) the ability to supply water resources and water safety in terms of both quantity and quality within a changing environment. However, opportunities and challenges for ameliorating the problems exist, and new ideas and methodology to solve the problems have been proposed, such as the interface process study on the interactions in the soil,root interface, the plant,atmosphere interface, the soil,atmosphere interface, and the interface of soil water and groundwater. In order to manage water resources in a sustainable manner, the study of water resources' renewal ability as affected by natural change and human activity is addressed from the viewpoint of both water quantity and quality, and their integration. To reduce the vulnerability of water resources in regional water management, a paradigm of sustainable water resources utilization is also proposed, using water,heat balance, water,salt balance, water,sediment balance, and water supply,demand balance. This approach may help reveal the basic problems and point to possible approaches to solving the water problems in North China in the 21st century. Copyright © 2004 John Wiley & Sons, Ltd. [source] Assessment of the water,salinity crop production function of wheat using experimental data of the Golestan province, Iran,IRRIGATION AND DRAINAGE, Issue 4 2009A. R. Kiani stress hydrique; stress de salinité; fonctions de production; blé Abstract Optimisation of agricultural water management in arid and semi-arid regions requires the availability of water,salinity crop production functions. A two-year experiment was conducted in the northern Golestan province of Iran to assess the water,salinity production function of wheat. The treatments in the experiment consisted of four levels of irrigation water, i.e. 50 (W1), 75 (W2), 100 (W3) and 125 (W4) % of crop water requirement, and four levels of water salinity, respectively 1.5 (S1), 8.5 (S2), 11.5 (S3) and 14.2 (S4) dS,m,1. The plots were arranged in a randomised complete block design with three replications and water quantity as main plot treatment and water quality as subplot treatment. The data were analysed using linear, quadratic, Cobb,Douglas and transcendental functions, complemented with an economic analysis. The results indicate that for the given climate,soil conditions, transcendental functions best predict wheat yield under both water and salinity stress conditions. Yield reduction caused by a unit increase of matric potential is found to be larger than that caused by a unit increase of osmotic potential. The marginal rate of technical substitution indicates that each one of the two factors studied, namely soil salinity and water supply, can be substituted with the other in a wide range in order to achieve equal amount of yield. Copyright © 2008 John Wiley & Sons, Ltd. L'optimisation de la gestion de l'eau agricole dans les zones arides et semi-arides nécessite de savoir la relation entre l'apport d'eau selon sa salinité et la production végétale. Une expérience de deux ans a été menée dans le nord de la province du Golestan en Iran pour évaluer la fonction de production de l'eau saline sur le blé. Les traitements expérimentaux consistaient en quatre niveaux d'apports d'eau soit 50% (W1), 75% (W2), 100% (W3) et 125% (W4) des besoins en eau des cultures, et quatre niveaux de salinité de l'eau, respectivement 1.5 (S1), 8.5 (S2), 11.5 (S3) et 14.2 (S4) dS,m,1. Les parcelles ont été disposées dans un bloc de Fisher randomisé avec trois répétitions avec la quantité de l'eau comme variable principale et la qualité de l'eau comme variable secondaire. Les données ont été analysées en utilisant les fonctions linéaires, quadratiques, Cobb,Douglas et transcendantes, complétées par une analyse économique. Les résultats indiquent que, pour un climat et un état du sol donnés, les fonctions transcendantes donnent les meilleures prédictions du rendement de blé en condition de salinité et de stress hydrique. La baisse de rendement causée par une augmentation d'une unité de potentiel hydrique est plus importante que celle causée par l'augmentation d'une unité de potentiel osmotique. Le taux marginal de substitution technique indique que chacun des deux facteurs étudiés, à savoir la salinité des sols et l'apport d'eau, peuvent être largement substitués l'un à l'autre pour viser rendement identique. Copyright © 2008 John Wiley & Sons, Ltd. [source] Similarities and differences in the historical development of flood management in the alluvial stretches of the Lower Mississippi Basin and the Rhine Basin,§IRRIGATION AND DRAINAGE, Issue S1 2006Dick de Bruin ingénierie hydraulique fluviale; développement historique des bassins du Rhin et du Mississippi inférieur; plaines alluviales Abstract Although the rivers Rhine and Mississippi cannot be compared as features of nature,the Mississippi River as a feature of nature is much bigger and more impressive than the Rhine,one can still observe striking similarities on flood management in both river basins, in particular in the alluvial flat reaches. But there are also some fundamental differences, not only technically but also institutionally. Since industrialization (around 1800), inland navigation became a major user on both river systems and later flood control started developing more fundamentally. Large intervention works were needed, mainly developed and based on trial and error. In both cases it has led to irreversible effects, which demand continuous attention. For the alluvial stretches in both river basins, a review is given on the most important developments in river engineering over the last two centuries. For both rivers, nautical management and flood control were held in one institutional hand at national/federal level, because both uses/sectors need the creation and regular maintenance of one similar issue: a stable and deep main channel. But the way in which in particular flood management gradually developed institutionally, as an essential part of integrated water management in the alluvial flat lower reaches of both river systems, has diverged. Discussions on financing, priorities, public disclosure, multifunctional aspects, etc. have led in both basins to lengthy procedures and complicated policy making. This paper elaborates on the historic development of fundamentals in river engineering and river management in the alluvial plains of the Rhine Basin and the Lower Mississippi Basin, more in particular focusing on the development of flood protection dikes, and on the stabilization of major channels. Copyright © 2006 John Wiley & Sons, Ltd. Bien que le Rhin et le Mississippi ne puissent pas être comparés en termes physiques,le Mississippi est beaucoup plus grand et impressionnant que le Rhin,on peut pourtant observer des similitudes saisissantes dans la protection contre les inondations des deux bassins, en particulier dans les plaines alluviales. Mais il existe également quelques différences fondamentales, non seulement techniques mais institutionnelles. Depuis les débuts de l'industrialisation (vers 1800), la navigation est devenue un usage très important sur les deux fleuves et la protection contre les inondations à commencer à se mettre en place de façon plus systématique. De grands travaux d'intervention ont été nécessaires, principalement basés sur la règle empirique de l'essai/erreur. Dans les deux cas, ceci a entraîné des effets irréversibles, qui nécessitent une surveillance permanente. Pour les plaines alluviales des deux bassins, l'article passe en revue la plupart des développements de l'ingénierie hydraulique fluviale des deux cent dernières années. Pour les deux fleuves, la gestion de la navigation et la protection contre les inondations ont été regroupées dans une même institution au niveau national/fédéral, parce que les deux usages/secteurs demandaient la création et l'entretien régulier d'une même infrastructure: un canal principal stable et profond. Mais la manière dont la protection contre les inondations s'est progressivement développée sur le plan institutionnel, comme élément essentiel de la gestion intégrée de l'eau dans les plaines alluviales des deux fleuves, s'est différenciée. Des débats sur le financement, les priorités, l'information du public, les aspects multi fonctionnels, etc., ont conduit les deux bassins à mettre en place des procédures lourdes et des prises de décision complexes. Cet article présente le développement historique des principes fondamentaux de l'hydraulique fluviale et de la gestion de fleuve dans les plaines alluviales du bassin du Rhin et du bassin inférieur du Mississippi, en mettant l'accent sur le développement des digues de protection et la stabilisation des canaux principaux. Copyright © 2006 John Wiley & Sons, Ltd. [source] The role of economics in irrigation water management,,IRRIGATION AND DRAINAGE, Issue 2 2006Petra J. G. J. Hellegers allocation optimale de l'eau; fonction de satisfaction sociale; instruments économiques Abstract Economic literature and international conferences have extensively discussed the importance of treating irrigation water as an economic good, but there is still confusion about the role of economics in irrigation water management. Economics provides us with two contributions: analytical tools that help predict and interpret implications of various allocation procedures, and economic instruments that can assist in guiding users towards socially desirable outcomes. In this article the potential role of both contributions to improved irrigation water management is discussed, which is an extension of conventional work in this field. It becomes clear that, at this point in time, there is little empirical evidence of the effectiveness of economic instruments in irrigation water management. Economics mainly plays a role in understanding the implications of different procedures for allocating water, and guiding policymakers in defining appropriate allocation rules. Copyright © 2006 John Wiley & Sons, Ltd. La littérature économique et les conférences internationales ont débattu en détail de l'importance de traiter l'eau d'irrigation comme un bien économique, mais il règne encore une certaine confusion sur le rôle de l'économie dans la gestion de l'eau en irrigation. La science économique nous fournit deux contributions: des outils analytiques qui aident à prévoir et à interpréter les implications de diverses procédures d'allocation, et des instruments économiques qui peuvent aider à guider les usagers vers des effets socialement souhaitables. Dans cet article le rôle potentiel de ces deux apports dans l'amélioration de la gestion de l'eau en irrigation est examiné, ce qui va plus loin que l'approche traditionnelle dans ce domaine. Il devient clair que, à ce jour, il existe peu de preuves empiriques de l'effectivité des instruments économiques dans la gestion de l'eau en irrigation. L'économie joue surtout un rôle dans la compréhension des implications des différentes procédures d'allocation de l'eau, et dans la définition des règles d'allocation appropriées. Copyright © 2006 John Wiley & Sons, Ltd. [source] A model for optimisation of water management in rice polders in Thailand,IRRIGATION AND DRAINAGE, Issue 5 2005Preecha Wandee modèle mathématique; polders de riz; polder système de gestion de l'eau; optimisation Abstract This paper presents a mathematical model for the determination of optimal values for the main components of water management systems in rice polders in Thailand. The aim of the water management system in a rice area is to create good growing conditions for the crops. Under the hydrological conditions of Thailand the average rainfall during the rainy season is more than enough for growing rice or other crops. However, during the dry season there is a very small amount of rainfall. Thus the farmers are confronted with two quite different conditions and water management has to deal with irrigation and drainage issues. The main components of the water management system in a rice polder are the water level in the canals, the percentage of open surface water, discharge capacity from the field and discharge capacity of the pumping station or sluice. A model has been developed that takes into account damage due to flooding and drought as well as construction and maintenance cost for irrigation and drainage systems based on the hydrological conditions. Optimising of such a water management system means determining the main components in such a way that the equivalent annual costs are minimal. A case study has been done for a rice polder in Suphanburi province. It was found that the polder water level for rice under rainfed conditions could be kept above ground level to minimise loss of water from the rice field, whereas under irrigated conditions the polder water level has to be kept below ground level to get good drainage conditions. Copyright © 2005 John Wiley & Sons, Ltd. Cet article présente un modèle mathématique pour l'optimisation des composants principaux du système de gestion de l'eau dans des polders de riz en Thaïlande. Le but du système de gestion de l'eau dans un secteur de riz est de créer de bonnes conditions de croissance pour les récoltes. Dans la situation hydrologique de la Thaïlande les précipitations moyennes pendant la saison des pluies sont plus que suffisantes pour cultiver du riz croissant ou d'autres récoltes. Cependant, durant la saison sèche il y a très peu de précipitations. Ainsi les fermiers sont confrontés à deux conditions tout à fait différentes. Par conséquent la gestion de l'eau doit prendre en compte des problèmes d'irrigation et de drainage. Les composants principaux du système de gestion de l'eau dans un polder de riz sont le niveau d'eau dans les canaux, le pourcentage de l'eau ouverte, la capacité de décharge du champ et capacité de décharge de la station de pompage ou d'écluse. On a développé un modèle qui tient compte des dommages dus à l'inondation et à la sécheresse aussi bien que du coût de construction et d'entretien pour l'irrigation et à la canalisation basée sur les conditions hydrologiques. La linéarisation d'un tel système de gestion de l'eau implique de déterminer les composants principaux de telle manière que le système entier ait le coût équivalent annuel minimum. Une étude de cas a été faite pour un polder de riz dans la province de Suphanburi. On a constaté que le niveau d'eau du polder pour le riz irrigué à l'eau de pluie pouvait être gardé au-dessus du niveau du sol pour réduire au minimum la perte d' eau de la rizière, tandis que dans des conditions irriguées le niveau d'eau de polder doit être gardé au-dessous du niveau du sol pour obtenir de bonnes conditions de drainage. Copyright © 2005 John Wiley & Sons, Ltd. [source] Optimization of water management in the RUT Irrigation District, Colombia,IRRIGATION AND DRAINAGE, Issue 1 2004Herman Depeweg canaux d'irrigation; régulation de canaux; simulation des écoulements en canal Abstract The RUT Irrigation District is a flat polder area with an infrastructure for irrigation, drainage and flood protection. Water is pumped out for drainage, mainly during the wet season and is pumped in for irrigation during the two growing seasons. The RUT Irrigation District is one of the 16 districts that were transferred by the Colombian government to a water users' association. During this process the farmers agreed to take over the management and to give up governmental subsidies. It appeared that the farmers grossly underestimated the future energy costs and nowadays they complain about high costs for operation and maintenance of the pumping stations. In addition, the service provided is not adequate and the condition of the pumps is declining. The supplementary irrigation is based on the rainfall deficit, but a distinct criterion to supply water according to daily rainfall and cropping calendar does not exist. Hence, it is possible that more water than required is supplied to the area, affecting not only the pumping costs for irrigation but also for drainage. The present situation has been evaluated with a water balance at scheme level and an analysis of the measured groundwater fluctuations. Consecutively, a water balance at field level with an unsaturated groundwater flow model has been simulated to determine the irrigation requirements, yield reduction and drain flow based on a 20-year analysis. The water balance at field level and the one-, two- and three-day rainfall with a return period of 5 years resulted in design drain flows. Finally, these flows were used in hydrodynamic simulations to analyse the pumping requirements for optimal drainage. The simulations also indicated the inundated areas to be expected for different rainfall intensities and frequencies. Copyright © 2004 John Wiley & Sons, Ltd. Le district de RUT possède un système d'irrigation et de drainage avec une protection contre les inondations. L'eau est non seulement pompée pour assurer le drainage du polder durant la saison humide, mais aussi pour alimenter le système d'irrigation durant les deux saisons agricoles. Le district de RUT est l'un des seize districts transférés par le gouvernement colombien à une association d'usagers de l'eau. Durant ce transfert, les exploitants agricoles ont accepté de prendre en charge la gestion et d'abandonner les aides gouvernementales. Il est apparu alors que les exploitants agricoles se plaignent des couts élevés pour l'opération et la maintenance des stations de pompages. De plus, le service fourni n'est pas adéquat et les pompes se détériorent. L'irrigation de complément est fonction des précipitations, mais il n'existe pas de critère précis pour la fourniture d'eau en fonction de précipitations quotidiennes ou du calendr des récoltes. Il est ier possible qu'une quantité d'eau supérieure à celle requise soit apportée au système, affectant non seulement les exigences de pompage pour l'irrigation mais aussi pour le drainage. L'évaluation de la situation actuelle est basée sur un bilan hydrique à l'échelle de système et sur une analyse des fluctuations des eaux souterraines. Par la suite, un bilan hydrique a l'échelle de la campagne délivré par le model WASIM a été utilisé pour déterminer les exigences d'irrigation, la réduction des récoltes et le débit dans le drain basé sur une simulation de 20 ans. Enfin, le drain principal fut simulé avec DUFLOW pour analyser les caractéristiques du pompage pour le drainage utilisant le débit de drainage fourni par un bilan hydrique pour des durées deun, deux et trois jours de pluie fréquence de quinquennale. La simulation a aussi permis d'identifier les étendues des inondations pour différentes intensités et fréquences de pluie. Copyright © 2004 John Wiley & Sons, Ltd. [source] Non,Market Interventions in Water,Sharing:Case Studies from West Bengal, IndiaJOURNAL OF AGRARIAN CHANGE, Issue 4 2002Vikas Rawal This paper deals with two issues that are important areas of concern in the recent literature on water management in less,developed countries: forms of ownership of groundwater resources and alternatives to anarchy in the exploitation and use of groundwater. The emergence of a market for irrigation water has been argued to have the potential to provide irrigation water to large numbers of small cultivators in developing countries. The development of free markets for water, however, has also been shown to be associated with the emergence of ,water,lords' and with contracts for the purchase and sale of water that are biased against the poor. By contrast, this paper presents two examples of viable non,market interventions in water,sharing , regulation of water markets by village councils and cooperative tubewell groups , from villages in West Bengal, India. These interventions both improved the efficiency of water,use and represented relatively equitable arrangements for water,sharing. [source] Kootenai River velocities, depth, and white sturgeon spawning site selection , a mystery unraveled?JOURNAL OF APPLIED ICHTHYOLOGY, Issue 6 2009V. L. Paragamian Summary The Kootenai River white sturgeon Acipenser transmontanus population in Idaho, US and British Columbia (BC), Canada became recruitment limited shortly after Libby Dam became fully operational on the Kootenai River, Montana, USA in 1974. In the USA the species was listed under the Endangered Species Act in September of 1994. Kootenai River white sturgeon spawn within an 18-km reach in Idaho, river kilometer (rkm) 228.0,246.0. Each autumn and spring Kootenai River white sturgeon follow a ,short two-step' migration from the lower river and Kootenay Lake, BC, to staging reaches downstream of Bonners Ferry, Idaho. Initially, augmented spring flows for white sturgeon spawning were thought to be sufficient to recover the population. Spring discharge mitigation enhanced white sturgeon spawning but a series of research investigations determined that the white sturgeon were spawning over unsuitable incubation and rearing habitat (sand) and that survival of eggs and larvae was negligible. It was not known whether post-Libby Dam management had changed the habitat or if the white sturgeon were not returning to more suitable spawning substrates farther upstream. Fisheries and hydrology researchers made a team effort to determine if the spawning habitat had been changed by Libby Dam operations. Researchers modeled and compared velocities, sediment transport, and bathymetry with post-Libby Dam white sturgeon egg collection locations. Substrate coring studies confirmed cobbles and gravel substrates in most of the spawning locations but that they were buried under a meter or more of post-Libby Dam sediment. Analysis suggested that Kootenai River white sturgeon spawn in areas of highest available velocity and depths over a range of flows. Regardless of the discharge, the locations of accelerating velocities and maximum depth do not change and spawning locations remain consistent. Kootenai River white sturgeon are likely spawning in the same locations as pre-dam, but post-Libby Dam water management has reduced velocities and shear stress, thus sediment is now covering the cobbles and gravels. Although higher discharges will likely provide more suitable spawning and rearing conditions, this would be socially and politically unacceptable because it would bring the river elevation to or in excess of 537.66 m, which is flood stage. Thus, support should be given to habitat modifications incorporated into a management plan to restore suitable habitat and ensure better survival of eggs and larvae. [source] Ecologically Functional Floodplains: Connectivity, Flow Regime, and Scale,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 2 2010Jeffrey J. Opperman Opperman, Jeffrey J., Ryan Luster, Bruce A. McKenney, Michael Roberts, and Amanda Wrona Meadows, 2010. Ecologically Functional Floodplains: Connectivity, Flow Regime, and Scale. Journal of the American Water Resources Association (JAWRA) 46(2):211-226. DOI: 10.1111/j.1752-1688.2010.00426.x Abstract:, This paper proposes a conceptual model that captures key attributes of ecologically functional floodplains, encompassing three basic elements: (1) hydrologic connectivity between the river and the floodplain, (2) a variable hydrograph that reflects seasonal precipitation patterns and retains a range of both high and low flow events, and (3) sufficient spatial scale to encompass dynamic processes and for floodplain benefits to accrue to a meaningful level. Although floodplains support high levels of biodiversity and some of the most productive ecosystems on Earth, they are also among the most converted and threatened ecosystems and therefore have recently become the focus of conservation and restoration programs across the United States and globally. These efforts seek to conserve or restore complex, highly variable ecosystems and often must simultaneously address both land and water management. Thus, such efforts must overcome considerable scientific, technical, and socioeconomic challenges. In addition to proposing a scientific conceptual model, this paper also includes three case studies that illustrate methods for addressing these technical and socioeconomic challenges within projects that seek to promote ecologically functional floodplains through river-floodplain reconnection and/or restoration of key components of hydrological variability. [source] Delving into the "Institutional Black Box": Revealing the Attributes of Sustainable Urban Water Management Regimes,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 6 2009Susan J. Van De Meene van de Meene, Susan J. and Rebekah R. Brown, 2009. Delving into the "Institutional Black Box": Revealing the Attributes of Sustainable Urban Water Management Regimes. Journal of the American Water Resources Association (JAWRA) 45(6):1448-1464. Abstract:, This paper is based on the proposition that the transition to sustainable urban water management has been hampered by the lack of insight into attributes of a sustainable urban water regime. Significant progress has been made in developing technical solutions to advance urban water practice, however it is the co-evolution of the socio-institutional and technical systems that enable a system-wide transition. A systematic analysis of 81 empirical studies across a range of practice areas was undertaken to construct a schema of the sustainable urban water regime attributes. Attributes were identified and analyzed using a framework of nested management regime spheres: the administrative and regulatory system, inter-organizational, intra-organizational, and human resources spheres. The regime is likely to involve significant stakeholder involvement, collaborative inter-organizational relationships, flexible and adaptive organizational cultures, and motivated and engaging employees. Comparison of the constructed sustainable and traditional regime attributes reveals that to realize sustainable urban water management in practice a substantial shift in governance is required. This difference emphasizes the critical need for explicitly supported strategies targeted at developing each management regime sphere to further enable change toward sustainable urban water management. [source] Review of Urban Stormwater Quality Models: Deterministic, Stochastic, and Hybrid Approaches,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 6 2007Christopher C. Obropta Abstract:, The growing impact of urban stormwater on surface-water quality has illuminated the need for more accurate modeling of stormwater pollution. Water quality based regulation and the movement towards integrated urban water management place a similar demand for improved stormwater quality model predictions. The physical, chemical, and biological processes that affect stormwater quality need to be better understood and simulated, while acknowledging the costs and benefits that such complex modeling entails. This paper reviews three approaches to stormwater quality modeling: deterministic, stochastic, and hybrid. Six deterministic, three stochastic, and three hybrid models are reviewed in detail. Hybrid approaches show strong potential for reducing stormwater quality model prediction error and uncertainty. Improved stormwater quality models will have wide ranging benefits for combined sewer overflow management, total maximum daily load development, best management practice design, land use change impact assessment, water quality trading, and integrated modeling. [source] EVALUATION OF A STREAM AQUIFER ANALYSIS TEST USING ANALYTICAL SOLUTIONS AND FIELD DATA,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 3 2004Garey A. Fox ABSTRACT: Considerable advancements have been made in the development of analytical solutions for predicting the effects of pumping wells on adjacent streams and rivers. However, these solutions have not been sufficiently evaluated against field data. The objective of this research is to evaluate the predictive performance of recently proposed analytical solutions for unsteady stream depletion using field data collected during a stream/aquifer analysis test at the Tamarack State Wildlife Area in eastern Colorado. Two primary stream/aquifer interactions exist at the Tamarack site: (1) between the South Platte River and the alluvial aquifer and (2) between a backwater stream and the alluvial aquifer. A pumping test is performed next to the backwater stream channel. Drawdown measured in observation wells is matched to predictions by recently proposed analytical solutions to derive estimates of aquifer and streambed parameters. These estimates are compared to documented aquifer properties and field measured streambed conductivity. The analytical solutions are capable of estimating reasonable values of both aquifer and streambed parameters with one solution capable of simultaneously estimating delayed aquifer yield and stream flow recharge. However, for long term water management, it is reasonable to use simplified analytical solutions not concerned with early-time delayed yield effects. For this site, changes in the water level in the stream during the test and a varying water level profile at the beginning of the pumping test influence the application of the analytical solutions. [source] | |||||||||||||||||||||||||