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In its 50 years of existence, the International Water Resources Association (IWRA) and its regionally and thematically diverse members have played a key role in producing and disseminating knowledg...

In the context of global warming and increasing human activities, the acceleration of the water cycle will increase the risk of basin drought. In this study, to analyze the spatial and temporal evolution characteristics of hydrological and meteorological droughts over the Hanjiang River Basin (HRB), the Standardized Precipitation Index (SPI) and Standardized Runoff Index (SRI) were selected and applied for the period 1961–2018. In addition, the cross-wavelet method was used to discuss the relationship between hydrological drought and meteorological droughts. The results and analysis indicated that: (1) the meteorological drought in the HRB showed a complex cyclical change trend of flood-drought-flood from 1961 to 2018. The basin drought began to intensify from the 1990s and eased in the 2010s. The characteristics of drought evolution in various regions are different based on scale. (2) During the past 58 years, the hydrological drought in the HRB has shown a significant trend of intensification, particularly in autumn. Also, the hydrological droughts had occurred frequently since the 1990s, and there were also regional differences in the evolution characteristics of drought in various regions. (3) Reservoir operation reduces the frequency of extreme hydrological drought events. The effect of reducing the duration and intensity of hydrological drought events by releasing water from the reservoir is most obvious at Huangjiagang Station, which is the nearest to Danjiangkou Reservoir. (4) The hydrological drought and meteorological drought in the HRB have the strongest correlation on the yearly scale. After 1990, severe human activities and climate change have not only reduced the correlation between hydrological drought and meteorological drought in the middle and lower reaches of the basin, but also reduced the lag time between them. Among them, the hydrological drought in the upper reaches of the basin lags behind the meteorological drought by 1 month, and the hydrological drought in the middle and lower reaches of the basin has changed from 2 months before 1990 to 1 month lagging after 1990. HIGHLIGHTS I discovered the evolution characteristics of meteorological and hydrological drought in the region.; I found the operating law of the reservoir has a greater impact on regional hydrology and drought.; I have identified the areas and times that are susceptible to drought.; I found the relationship between hydrological and meteorological drought.; I discovered the impact of human activities on the drought in the region.

Ensemble hydrologic forecasting which takes advantages of multiple hydrologic models has made much contribution to water resource management. In this study, four hydrological models (the Xin’anjiang model (XAJ), Simhyd, GR4J, and artificial neural network (ANN) models) and three ensemble methods (the simple average, black box-based, and binomial-based methods) were applied and compared to simulate the hydrological process during 1979–1983 in three representative catchments (Daixi, Hengtangcun, and Qiaodongcun). The results indicate that for a single model, the XAJ model and the GR4J model performed relatively well with averaged Nash and Sutcliffe efficiency coefficient (NSE) values of 0.78 and 0.83, respectively. For the ensemble models, the results show that the binomial-based ensemble method (dynamic weight) outperformed with water volume error reduced by 0.8% and NSE value increased by 0.218. The best performance on runoff forecasting occurs in the Hengtang catchment by integrating four hydrologic models based on binomial ensemble method, achieving the water volume error of 2.73% and NSE value of 0.923. Finding would provide scientific support to water engineering design and water resources management in the study areas.

In the context of global warming and increasing human activities, the acceleration of the water cycle will increase the risk of basin drought. In this study, to analyze the spatial and temporal evolution characteristics of hydrological and meteorological droughts over the Hanjiang River Basin (HRB); the Standardized Precipitation Index (SPI) and Standardized Runoff Index (SRI) were selected and applied for the period 1961–2018. In addition, the cross-wavelet method was used to discuss the relationship between hydrological drought and meteorological droughts. The results and analysis indicated that: (1) the meteorological drought in the HRB showed a complex cyclical change trend of flood-drought-flood from 1961 to 2018. The basin drought began to intensify from 1990s and eased in 2010s. The characteristics of drought evolution in various regions are different based on scale. (2) During the past 58 years, the hydrological drought in the HRB has shown a significant trend of intensification, particularly in autumn season. Also, the hydrological droughts had occurred frequently since the 1990s, and there were also regional differences in the evolution characteristics of drought in various regions. (3) Reservoir operation reduces the frequency of extreme hydrological drought events. The effect of reducing the duration and intensity of hydrological drought events by releasing water from the reservoir is most obvious at Huangjiagang Station, which is the nearest to Danjiangkou Reservoir. (4) The hydrological drought and meteorological drought in the HRB have the strongest correlation on the yearly scale. After 1990, severe human activities and climate change are not only reduced the correlation between hydrological drought and meteorological drought in the middle and lower reaches of the basin, but also reduced the lag time between them. Among them, the hydrological drought in the upper reaches of the basin lags behind the meteorological drought by 1 month, and the hydrological drought in the middle and lower reaches of the basin has changed from 2 months before 1990 to 1 month lagging after 1990.

Wastewater reuse is identified as strategic to help ameliorate scarcity in water-stressed regions around the world. However, to develop it, there is a need to better understand the social, institutional and technological contexts in which it takes place. This article develops a novel socio-technical framework to inform such an analysis and applies it to current wastewater reuse in Egypt. Our analysis highlights the different actors, management activities and practices that shape wastewater collection, transfer, treatment, discharge and/or reuse in different social, technological and environmental contexts in Egypt. It points out bottlenecks of current wastewater reuse policies and programmes.

Four years since the adoption of the Sustainable Development Goals, UN-Water reports show the world is off track to achieve the water goal – the heart of the SDGs-, thus the same goes for all water related SDGs (only 10 years to harvest SDGs). Amid lots of highlights on what we need to do, governments must decide how to incorporate SDG 6 targets into national planning processes, policies and strategies and set their own targets, taking into account local circumstances and contexts including cultural. The SDGs anticipate substantial improvements in the efficiency, productivity and sustainability of water use; safe treatment and reuse of wastewater; integrated approaches to water management; and, the resilient food production systems. When well-adapted and well-implemented, water accounting provides countries and/or regions that face increasing water scarcity a sound and transparent basis for managing the scarce water resources and take actions to achieve relevant SDGs and other targets including evaluating water resources plan and developments.

To achieve a water‐secure world, water management should be approached from a multidimensional and integrative perspective, addressing the water‐related issues of health, household supply, economics, the environment, and resilience to water‐related and climate change hazards. Although water security has significantly improved since 2000 in Africa, there are still vast inequalities in access to water suitable in terms of quantity and quality, especially in rural areas. To achieve water‐related sustainable development of African economies, a broad scope of innovative technological and management solutions is required, involving governments, research institutions, private sector parties, and civil society. This special series, composed of 8 papers, illustrates a selection of the most relevant results achieved by the 7 research projects selected and financed by the European Union under 2 dedicated Horizon 2020 calls in 2015: Water‐5b‐2015 “A coordination platform” and Water‐5c‐2015 “Development of water supply and sanitation technology, systems and tools, and/or methodologies.” The innovations presented in this special series include both technological advancements and w'ater management approaches, given that the development of water‐related technologies in developing countries needs to be integrated into water management strategies and economic instruments. This special series aims to help policy makers take informed decisions on how to implement innovative approaches to increase water security in African countries. Integr Environ Assess Manag 2020;16:853–855. © 2020 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC), KEY POINTS To achieve a more water secure world, water management should be approached from a multidimensional and integrative perspective.This special series aims to help policy makers take informed decisions on how to implement innovative approaches to increase water security in African countries.

Investigating long-term streamflow changes pattern and its response to climate and human factors is of crucial significance to understand the hydrological cycle under a changing environment. Caijiazhuang catchment located within Haihe River basin, north China was selected as the study area. To detect the trend and changes in streamflow, Mann–Kendall test was used. Elasticity and hydrological simulation methods were applied to assess the relative contribution of climate change and human activities on streamflow variability under three periods (baseline (1958–1977), impact I (1978–1997), and impact II (1998–2012)). The long-term hydro-climatic variables experienced substantial changes during the whole study period, and 1977 was the breaking year of streamflow change. Attribution analysis using the two methods showed consistent results: for impact I, climate change impacts explained 65% and 68% of streamflow reduction; however for impact II, it only represented 49% and 56% of streamflow reduction. This result indicated that human activities were intensifying over time. Various types of human activities presented significant effects on streamflow regimes including volumes and hydrographs. The findings of this paper could provide better insights of hydrological evolution and would thus assist water managers in sustainably managing and providing water use strategies under a changing environment.

China is planning to expand its coal power generation to meet its energy demand and support the economic development. The current level of water use for thermal power generation is 8% of total water use, China is a water-stressed country which is facing many new challenges including climate change and population growth. China’s future coal power industry will add further pressures on already stressed water resources. This raised the key question on how the limited water resources can be managed to meet the demand of planned coal power expansion. A great level of understanding on the present status of water use and forecasting future demand in coal power plant is very important to answer this question. However, knowledge gap, data availability and accessibility are the major challenge in this regard. This paper attempts to improve the knowledge of the water demand in the coal power generation plant in China by using a simple water use model. Furthermore, a method is proposed to forecast future water demand in coal power plant. The proposed method is applied for forecasting water demand in Shaanxi coal power bases in Northern China under four scenarios. The results showed that the future water demand for Shaanxi coal power base will increase by 102–161% compared to current use under different scenarios in order to increase the production capacity by 206%. Adopting the optimum level of current status of water use, it is possible to limit the increase in water demand by 102% or 47.119 million-m3. It is expected that the finding of the study would help decision-making processes in water resources management in Chinese coal power generation.

Agriculture and agri-food systems of the highly vulnerable Middle East and North Africa (MENA) region needs a radical transformation under a changing climate. Based on a two-year effort, initially we developed a mega hypothesis on how to achieve climate-smart agri-food transformation in the region. In the study, we hypothesized that “Climate-Smart Lifts” implemented in the enabling environments can rapidly facilitate agri-food transformation in the region. In order to gather the stakeholders’ perception about this, we organized a collective conversation among ~400 stakeholders that represent various scales and sectors within the agriculture sector in MENA. These “listening cum learning consultations” were conducted through a survey followed by a series of webinars. The webinar discussions were strategically guided based on our hypothesis, the responses from the surveys and the regional needs. These discussions provided a forum to bring-out the stakeholders’ perspective on what new knowledge, partnerships, instruments and projects were needed in the MENA. The deliberation focused on the opportunities of public–private partnerships focusing in all the four major agroecosystems in MENA (irrigated, rainfed, rangelands, and deserts). In result, we developed an effective framework for strategic resource mobilization in the region, keeping in view the strong regional needs for climate actions and the requisite long-term commitments for the SDGs implementation.

Similar to other modelling methodologies, the potential of system dynamics to contribute to system understanding and decision making depends upon the practices applied by the modeller. However lessons about many of these practices are often unreported. This paper contributes to the methodology of system dynamics modelling of socio-ecological systems by 1) examining issues modellers face during the modelling process, and 2) providing guidance on how to effectively design and implement system dynamics modelling. This is achieved through an investigation of five case studies, drawing on lessons from these experiences. This is complemented by a literature review of system dynamics applied within the context of integrated modelling and environmental DSS. The case studies cover a variety of environmental issues and system dynamics modelling methods and tools. Although we used system dynamics as the common lens from which lessons are drawn, many of these insights transcend to other integrated modelling approaches.

A framework is proposed for forecasting industrial water demand in the context of climate change, economic growth, and technological development. The framework was tested in five sub-basins of Huaihe River of China, namely Upstream of Huaihe River (UH), Middlestream of Huaihe River (MH), Downstream of Huaihe River (DH), Yishusi River (YSSR), and Coastal River of Shandong Peninsula (CSP) to project future changes in industrial water demand under different environment change scenarios. Results showed that industrial water demand in Huaihe River basin will increase in the range of 10 to 44.6% due to economic development, water-saving technological advances, and climate change. The highest increase was projected by general circulation model (GCM) BCC-CSM1–1 (179.16 × 108 m3) and the lowest by GCM GISS-E2-R (132.4 × 108 m3) in 2020, while the GCM BNU-ESM projected the highest increase (190.57 × 108 m3) and GCM CNRM-CM5 the lowest (160.41 × 108 m3) in 2030. Among the different sub-basins, the highest increase was projected in MH sub-basin where industrial water demand is already very high. On the other hand, the lowest increase in industrial water demand was projected in UH sub-basin. The rapid growth of high water-consuming industries and increased water demand for cooling due to temperature rise are the major causes of the sharp increase in industrial water demand in the basin. The framework developed in the study can be used for reliable forecasting of industrial water demand which in turn can help in selection of an appropriate water management strategy for adaptation to global environmental changes.

Conducting water resource assessment and forecasting at a basin scale requires effective and accurate simulation of the hydrological process. However, intensive, complex human activities and environmental changes are constraining and challenging the hydrological modeling development and application by complicating the hydrological cycle within its local contexts. Six sub-catchments of the Yellow River basin, the second-largest river in China, situated in a semi-arid climate zone, have been selected for this study, considering hydrological processes under a natural period (before 1970) and under intensive human disturbance (2000&ndash, 2013). The study aims to assess the capacity and performance of the hydrological models in simulating the discharge under a changing environment. Four well-documented and applied hydrological models, i.e., the Xin&rsquo, anjiang (XAJ) model, GR4J model, SIMHYD model, and RCCC-WBM (Water Balance Model developed by Research Center for Climate Change) model, were selected for this assessment. The results show that (1) the annual areal temperature of all sub-catchments presented a significant rising trend, and annual precipitation exhibited insignificant decline trend, (2) as a result of climate change and intensive human activities, the annual runoff series showed a declining trend with abrupt changes mostly occurring in the 1980s with the exception of the Tangnaihai station, (3) the four hydrological models generally performed well for runoff simulation for all sub-catchments under the natural period. In terms of Nash&ndash, Sutcliffe efficiency coefficient, the XAJ model worked better in comparison to other hydrological models due to its detailed representations and complicated mechanism in runoff generation and flow-routing scheme, (4) environmental changes have impacted the performance of the four hydrological models under all sub-catchments, in particularly the Pianguan River catchment, which is could be attributed to the various human activities that in turn represent more complexity for the regional hydrological cycle to some extent, and reduce the ability to predict the runoff series, (5) the RCCC-WBM model, well known for its simple structure and principles, is considered to be acceptable for runoff simulation for both natural and human disturbance periods, and is recommended for water resource assessment under changing environments for semi-arid regions.

Summary In this study, the application of Artificial Neural Networks (ANN) and Multiple regression analysis (MR) to forecast long-term seasonal spring rainfall in Victoria, Australia was investigated using lagged El Nino Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) as potential predictors. The use of dual (combined lagged ENSO–IOD) input sets for calibrating and validating ANN and MR Models is proposed to investigate the simultaneous effect of past values of these two major climate modes on long-term spring rainfall prediction. The MR models that did not violate the limits of statistical significance and multicollinearity were selected for future spring rainfall forecast. The ANN was developed in the form of multilayer perceptron using Levenberg–Marquardt algorithm. Both MR and ANN modelling were assessed statistically using mean square error (MSE), mean absolute error (MAE), Pearson correlation ( r ) and Willmott index of agreement ( d ). The developed MR and ANN models were tested on out-of-sample test sets; the MR models showed very poor generalisation ability for east Victoria with correlation coefficients of −0.99 to −0.90 compared to ANN with correlation coefficients of 0.42–0.93; ANN models also showed better generalisation ability for central and west Victoria with correlation coefficients of 0.68–0.85 and 0.58–0.97 respectively. The ability of multiple regression models to forecast out-of-sample sets is compatible with ANN for Daylesford in central Victoria and Kaniva in west Victoria ( r = 0.92 and 0.67 respectively). The errors of the testing sets for ANN models are generally lower compared to multiple regression models. The statistical analysis suggest the potential of ANN over MR models for rainfall forecasting using large scale climate modes.

Water resources are an integral part of the socio-economic-environmental system. Water resources have dynamic interactions with related social, economic and environmental elements, as well as regulatory factors that are characterized by non-linear and multi-loop feedbacks. In this paper, a complex System Dynamic (SD) model is used to study the relationship among population growth, economic development, climate change, management strategies and water resources, and identify the best management strategy to adapt with the changing environment in the Tuwei river basin of Northwest China. Three management alternatives viz. business as usual, water supply management and water demand management are studied under different climate change scenarios. Results indicate that water shortage rate in Tuwei river basin may increase up to 80 % by the year 2030 if current management practices are continued or the supply based management strategy is adopted. On the other hand, water demand management can keep the water shortage rate within a tolerable limit and therefore can be considered as the sustainable strategy for water resources management to maintain the economic growth and ecological status of the Tuwei river basin.

Water Scarcity and drought are recurrent phenomena in China. In the context of environmental change, an increasing tendency in drought frequency and severity is observed in China in recent years. Therefore, it is imperative to take necessary initiatives to reduce the impacts of drought. In this paper, an attempt is made to identify the best water management strategies to cope with droughts. For this objective the records of historical droughts and their impacts in China over the period of 1950–2009 are analyzed. It is observed that the drought affected area has increased nearly by 12 folds and the drought damaged area has increased by about 22 times in China in last 60 years. Over 87,000 reservoirs were built with a total water storage capacity of about 7,064 billion m3 to cope with droughts. However, this structural supply-based management strategy was not enough to meet the increasing water demand caused by rapid economic development and population growth. A typical relationship between socio-economic development and water resources management strategy to attain sustainability in water management is developed in this study. The relationship shows that the demand-side water management strategies can be the best option to meet the challenges posed by increased severity of drought, population growth, economic development and possible climate change. The concept is later verified through the analysis of changing pattern of water consumptions by different sectors in last 60 years.

Despite the perceived value of DSS in informing environmental and natural resource management, DSS tools often fail to be adopted by intended end users. By drawing together the experience of a global group of EDSS developers, we have identified and assessed key challenges in EDSS development and offer recommendations to resolve them. Challenges related to engaging end users in EDSS development emphasise the need for a participatory process that embraces end users and stakeholders throughout the design and development process. Adoption challenges concerned with individual and organisational capacities to use EDSS and the match between EDSS and organisational goals can be overcome through the use of an internal champion to promote the EDSS at different levels of a target organisation; co-ordinate and build capacity within the organisation, and; ensure that developers maintain focus on developing EDSS which are relatively easy and inexpensive to use and update (and which are perceived as such by the target users). Significant challenges exist in relation to ensuring EDSS longevity and financial sustainability. Such business challenges may be met through planning and design that considers the long-term costs of training, support, and maintenance; revenue generation and licensing by instituting processes which support communication and interactions; and by employing software technology which enables easy model expansion and re use to gain an economy of scale and reduce development costs. A final group of perhaps more problematic challenges relate to how the success of EDSS ought to be evaluated. Whilst success can be framed relatively easily in terms of interactions with end users, difficulties of definition and measurability emerge in relation to the extent to which EDSS achieve intended outcomes. To tackle the challenges described, the authors provide a set of best practice recommendations concerned with promoting design for ease of use, design for usefulness, establishing trust and credibility, promoting EDSS acceptance, and starting simple and small in functionality terms. Following these recommendations should enhance the achievement of successful EDSS adoption, but more importantly, help facilitate the achievement of desirable social and environmental outcomes.

Due to freshwater supplement scarcity and heavy human activities, the fresh water wetland ecosystem in Yellow River Delta is facing disintegrated deterioration, and it is seriously affecting the health of the Yellow River ecosystem. This paper identifies the restoration objectives of wetland aiming to protect ecological and economic values and development as well as the water resources of the Yellow River. The hydraulic and groundwater coupling model and Landscape Ecological Decision and Evaluation Support System (LEDESS) of the Yellow River Delta were established to calculate environmental flows of degraded wetlands. LEDESS is a computer-based model developed and used to assess and evaluate the effects of land-use changes on nature. In this study, LEDESS is used to assess and evaluate the ecological effects and the restoration possibilities considering several environmental flows' supplement scenarios. This included the changes of suitable habitat conditions and its ecological carrying capacities for indicator species, e. g., Red-crowned crane (Grus japonensis), Oriental stork (Ciconia boyciana), and Saunder's gull (Larus relictus), and changing of ecological patterns. The results showed that replenishing fresh water to wetlands is one of the effective adaptive measures to mitigate wetland degradation and improve its habitat quality and carrying capacities. This study indicated that landscape ecology approach is not only considered as a good way to solve complex problems in ecosystem management but also can be used to decide on the environmental flows and assess its ecological effects in large-scale wetland rehabilitation. This integrated method could make environmental flows estimated and assessment more rational than the results of hydrologic methods. It could assist decision makers to "see" the ecological effects after water supplementing and so alleviate the contradictions between environmental flows and production water demands, and can facilitate the implementation of environmental flows in most countries with water resources shortage.

Climate change and human activities have changed a number of characteristics of river flow in the northwest of China. Numerous problems such as water resource shortage, drying up of rivers, water pollution are the direct consequences of these changes. In this paper, we used the example of Yulin city in northwest China to assess the spatio-temporal characteristics and driving forces of annual river flow changes. Our research was based on the long-term time series of hydrological data from 1956 to 2005, to analyse annual flow in four main rivers (Kuye River, Tuwei River, Wuding River and Jialu River). The river flow depends upon the runoff characteristics of the river catchment, therefore we used variation ratio, variation index, unevenness, Runoff-Concentration Degree (RCD) and Runoff-Concentration Period (RCP) to determine the change in runoff characteristics of the four main rivers flows of the Yulin city. We tested the tendency of runoff by the Mann-Kendall non-parameter statistical method to obtain the...

Yellow River, is designated as “the cradle of Chinese civilization” and played a key role not only in the country’s economic development but also in the historic and cultural identity of the Chinese people. With the rapid economic development and population growth, water demand for industry and households has increased significantly in the Yellow River basin; this has caused an increasing gap between water supply and demand. Competing water demands triggered conflicts between disparate water users on different scales such as the rich and the poor, or between different sectors and regions, such as domestic and agriculture, agriculture and industry, upstream and downstream, rural and urban areas, etc. Ensuring equity in water supply for conflicting water users is one of the major challenges that facing water managers and in particular water management in the Yellow River basin. In this paper, a method has been developed to calculate the Gini coefficient of water use as an indicator to measure the equality in domestic water supply. A dual domestic water use structure model is employed for this purpose. The developed method is subsequently applied to assess the equality in domestic water supply in the Yellow River. Data of population growth, domestic water use and economic development over the time period 1999-2006 are used to calculate the Gini coefficient of water use over the same length of period. The result shows a decreasing trend in Gini coefficient of domestic water use in the Yellow River basin after 2001 which means domestic water use is becoming more and more equitable in the basin. The study justifies that the Gini coefficient of water use can be used and recommended as a useful tool for the water management especially in the context of global change.

Water security is an integral aspect of the socio-economic development in China. Nevertheless, water resources are under persistent pressures because of the growing population, heavy irrigation, climate change effects and short-term policies. Traditional management approaches narrowly focus on increasing supply and reducing demand without considering the complex interactions and feedback loops that govern water resource behaviour. Whereas these approaches may provide quick fix solutions, they often lead to unanticipated, sometimes catastrophic, delayed outcomes. Therefore, water management needs to take a holistic approach that caters to the interdependent physical (e.g. water inflows, outflows) and behavioural (e.g. decision rules, perceptions) processes in the system. Unlike reductionist approaches, System Dynamics (SD) takes a system-level view for modelling and analysing the complex structure (cause–effect relationships, feedback loops, delays) that generates the systemic behaviour. Simulating the SD model allows assessing long-term system-wide impacts, exploring leverage points and communicating results to decision makers. In this paper, we follow an SD modelling approach to examine the future of water security in Yulin City. First, we present a conceptual model for integrating water supply and demand. Based on this, we build an SD model to simulate and analyse the dynamics of water resource over time. The model output is tested to ensure that it satisfactorily replicates the historical behaviour of the system. The model is used to quantitatively assess the effectiveness of various supply/demand management options. Three scenarios are designed and examined: business-as-usual, supply management, and demand management. Results show that current management regime cannot effectively meet the future water demand. Whereas supply acquisition provides short-term benefits, it cannot cope with the growing population. A combination of conservation measures and demand-management instruments is regarded the most effective strategy for balancing supply and demand.

An indicator defined as a function of the to- tal water diversion through the Coleambally canal and the potential irrigation demand is selected to represent the sus- tainability of the irrigation water system in the Coleambally irrigation area, Australia. A simulation procedure using a system dynamics approach was developed to evaluate the in- dicator. The procedure includes water diversion assessment, potential crop water demand and total gross margin. Three cases of water supply options (surface water, ground water pumping and water trading), two cases of changes in the total agricultural area and three cropping pattern sce- narios were simulated to better understand their impact on sustainability. The simulated results indicate that increasing the agricultural area reduces the sustainability of the irriga- tion system because the demand of water increased despite in- crease in the gross margin. The scenarios show that imposed water trading and ground water pumping would considerably increase the supply system having a positive impact on the sustainability. The paper concludes that a multi-objective sustainability indicator taking account of economic and envi- ronmental issues could be more useful.

A frame work was presented for the assessment of the quality of life through the development of different indicators applied for Egypt. This paper focuses on the assessment of the quality of life using previously developed indicators in the first part of the study. A GIS user-friendly interface was developed to enhance the presentation of the study. This enables non technical users to directly use the developed GIS application to explore different concerns. Three cases were demonstrated in this paper, where an assessment of the quality of life of farmers, civilians, and agricultural investors was attained under specific scenario in each case. Assessment for other cases can still be made by browsing through the dropdown menu for each interest group under the selected scenario. Based on the demonstrated results for the three groups of people, it was found that the quality of life for a certain group of people under the strict scenario is in general less than the quality of life for the same group under the relax scenario.

Improving the efficiency of water allocation has long been recognised as a key problem for the water resources management decision-makers. However, assessing the efficacy of management decision is difficult due to the complexity and interconnectivity of water resource systems. For this reason, it is vital that robust modelling approaches are employed to deal with the feedback loops inherent in the water resource systems. Whilst many studies have applied modelling to various aspects of water resource management, little attention has been given to innovations in modelling approaches to deal with the modelling challenges associated with improving decision-making. The aim of this study is to apply a System Dynamics modelling approach to improve the efficiency of water allocation incorporating a myriad of irrigation system constraints. The system dynamic approach allows the different system components to be organised as a collection of discrete objects that incorporate data, structure and function to generate complex system behaviour. Through the application of a system dynamic approach, a robust model (named the Economical Reallocating Water Model (ERWM)) was developed which was used to examine the options of re-allocating water resources that minimize the water cost all over an irrigated agricultural area. The ERWM incorporated a wide range of complexities likely to be encountered in water resource management: surface and ground water sources, water trading between sources, system constraint such as maximum ground water pumping, rates, maximum

The Gnangara Sustainability Strategy is a cross-government initiative that aims to ensure there is sufficient groundwater in the Gnangara Mound for drinking and commercial use, and to meet existing and future environmental needs. The Gnangara Groundwater System (GGS) is a large aquifer situated in the southwest region of Western Australia. Historically, the GGS has been considered to be an infinite reservoir for water, but this impression has quickly shifted following the realization that 45 GL of water has been lost per annum since the late 1990s. The main causes for this loss are lower rainfall since 1975; land uses that reduce recharge; and increased water extraction. As a result, many significant environmental features, especially wetlands, are declining in health and value. The GGS faces increasing demands for its water from several key users within the public water supply, environmental and agricultural sectors. However, declining water levels related to climate change, demand urgent prioritisation of a set of inter-sectoral and inter-temporal land use planning and water abstraction rules that would maximize societal welfare while ensuring the sustainability of this crucial water source and its dependant ecosystems. The sustainable management of the GGS is a major problem for water and environmental Innovative modelling approaches should be employed to assist in better decision making by modelling the feedback loops inherent in the system and analysing the impact of alternative land use and water policy scenarios. This paper details a systems approach to developing an integrated decision

The objective of this paper is to develop and present a GIS-based and software tool capable of data management, data visualisation, and data analysis. The developed software is proved to be a good tool in the initial assessment of the quality status of the Nile river water quality. In addition a Graphical User Interface (GUI) was fully designed and implemented to make the GIS tool very easy and handy for the decision maker. Spatial analysis and visualisation of water quality data can be easily presented through the interface. It is concluded that water quality along the main stem is much better than the quality along the two main branches, where more violations are observed.

Water sharing management is the major problem for water resources and irrigation management decision makers. However, irrigation systems are very complex and interconnected, posing significant difficulties in managing irrigation economically and environmentally. Therefore, it is imperative that innovative modelling approaches are employed to deal with the feedback loops inherent in these systems. Through the application of a system dynamics approach, a Network Simulation Model (NSM) was developed. The purpose of the NSM is to measure and identify the change in economic and environmental outputs of various allocations and demand scenarios. The aim of this study is to examine the use of two methods of auto calibration (single objective and multiobjective) over a variety of climatic and hydrological conditions. These methods have been compared and applied to three periods of calibration and validation using seven performance criteria. Results indicate that multiobjective method yields better identifiable parameters and an improved model structure