Water Resource Constraints Research Articles

ADOPTION OF WATER AND SOIL CONSERVATION PRACTICES: THEORETICAL FRAMEWORKS AND ATTITUDINAL COMPONENTS

Agricultural production requires two main resources; water, as a source of life, and soil, as a living environment. Water and soil conservation is a critical issue in areas facing water and soil resource constraints. The purpose of this review paper is to provide an overview on the theoretical frameworks used in the analysis of the adoption of water and soil conservation practices. Different models and frameworks have been used in the analysis of the acceptance and/or adoption of new technologies and practices; these include Technology acceptance model, Motivational model, Theory of reasoned action, theory of planned behavior, Innovation diffusion theory and the Unified theory of acceptance and use of technology. The Icek Ajzen’s Theory of Planned Behavior (TPB) has been used as a conceptual framework in many studies on the factors affecting the adoption of water and soil conservation practices. The TPB allows examining the impact of individual factors (i.e. attitude), social norms (cf. subjective norms) and situational factors (i.e. perceived behavioral control) on the adoption of practices. It posits that if a person assesses the suggested behavior as positive (cf. attitude) and if he/she thinks that others want them to perform the behavior (cf. subjective norm), these result in a higher intention and motivation to do so. However, the TPB has some limitations such as not considering environmental/contextual and economic factors that may affect the individual’s intention to perform a behavior. Therefore, despite the widespread use of the TPB model, the paper concludes that the UTAUT seems a better model in understanding the dynamics of acceptance and adoption of water and soil conservation practices.

Spatial and temporal analyses of potential land use conflict under the constraints of water resources in the middle reaches of the Heihe River

With the rapid urbanization in China, land resources are becoming increasingly scarce. Identifying and resolving land use conflict is essential for reasonably using land resources and achieving land sustainability. Taking the middle reaches of the Heihe River as an example, we included the constraints of local water resources to construct a multi-criteria evaluation system for assessing land use competitiveness in 2000 and 2015 based on land use, socio-economic, and nighttime light data. By comparing the competitiveness of cultivated land, construction land and ecological land, we then derived the spatiotemporal patterns of potential land use conflicts. Actual land use changes supported the hypothesis that land use tended to convert into the type with higher competitiveness at areas with intense conflict, which better indicated that our assessment model was effective. The results showed that the potential land use conflict was more acute in the central and northwest but weak in the southeast and northeast, and its pattern showed a significantly positive spatial autocorrelation. The conflict between cultivated land and construction land was most prominent and mainly occurred in the transitional zone from urban to rural areas. Rapid urban development and water shortage were the main causes of the potential land use conflict. Assessing land use multi-functions and making a tradeoff among ecological, economic, and social services will be an effective way to guide future land use to solve land use conflict. Our research provides scientific evidence for sustainable land use planning and management in the arid areas.

Simulation of water balance equation components using SWAT model in Samalqan Watershed (Iran)

The disparate temporal and local distribution of freshwater and the rapid growth of the population in recent decades have led to problems in providing water resources for various applications. Hence, the supply of water in many countries such as Iran has become one of the most important challenges of the present century. Modern mathematical models have been developed for studying the complex hydrological processes of a watershed. The application of conceptual hydrological models is an important issue in watersheds for researchers, especially in arid and semiarid regions. The hydrological behaviors are complicated in such watersheds, and their calibration is more difficult. In this research, the conceptual and semidistributed SWAT model is used for Samalqan watershed, Iran, with 1148 km2 area. Streamflow simulation is considered for 13 years. Samalqan watershed modeling led to 22 subbasins and 413 hydrologic response units. Water balance components have been computed, the results have been calibrated with the SUfI2 approach in the SWAT-CUP program, and finally, the performance of the model is evaluated. The sensitivity analysis was conducted using 26 SWAT parameters. The most sensitive parameters were CN2 (moisture condition II curve number), GWQMN (threshold water level in shallow aquifer for base flow), GW_Delay (delay time for aquifer recharge), GW_REVAP (Revap coefficient), and ESCO (Soil evaporation compensation coefficient). The model was calibrated from 2004 to 2012 and validated from 2012 to 2014. The coefficient of determination (R2) and Nash and Sutcliffe efficiency (NSE), On monthly basis, were between 0.60–0.80 and 0.80–0.95 respectively, for calibration, and 0.70–0.90 and 0.70–0.80, respectively, for validation periods, which indicates that the model results are satisfactory. Results show that the SWAT model can be used efficiently in semiarid regions to support water management policies and development of sustainable water management strategies. Due to the arid and semiarid climate of Iran and water resources constraints, the need for modeling is clear. It can be concluded that determination of the existing water potential is necessary for water planning and management of water resources in the watershed.

Eco-efficiency of oasis seed maize production in an arid region, Northwest China

Improving eco-efficiency in arid areas is the crucial to resolve the dual constraints of scarce water resources and the fragile carrying capacity of the ecological environment on agricultural production. This study investigated the eco-efficiency of seed maize production in Zhangye City, the largest seed maize producer in the arid northwestern region of China. The environmental impacts were assessed through a life cycle assessment and incorporated into a data envelopment analysis model, together with economic factors to evaluate ecological efficiency. A Tobit regression model was applied to identify the key elements affecting eco-efficiency and determine suggestions for further improvements. The results showed that the environmental acidification index of Zhangye was 1.2079–1.3978 times larger than the world per capita level, with the primary cause being the application of nitrogen fertilizer. Water consumption was lower than the world average level. The comprehensive environmental index was lower than the 2000 world per capita level but higher than that of other Chinese regions. A production eco-efficiency evaluation showed that 14.68% of households achieved relatively efficient production. Water was the most influential element. Each additional 100 units of water reduce eco-efficiency by 0.34%. A comparative study of small, medium and large farms was carried out to examine the effect of farm size. Small farms were the most eco-efficient, followed by medium-sized farms, with large farms having the lowest eco-efficiency. The results highlighted that certain targeted policy interventions may be inefficient, including interventions focusing on expansion of the production scale, and that restrictions on fertilizer use and improving water-saving facilities can improve eco-efficiency performance.

Varietal adaptations matter for agricultural water use – a simulation study on grain maize in Western Switzerland

Climate change is altering agricultural production conditions. Adaptation measures to reduce negative impacts of climate change and utilize emerging potentials may involve the increased use of irrigation water. With increased irrigation water consumption, water use conflicts and resource constraints may occur and aggravate under climate change. Estimates of expected changes in irrigation water demands are of great value to anticipate if and where such issues may arise. This study presents an analysis of projected changes in irrigation water demand and grain yield of maize subject to variation in cultivar choice, sowing dates, soil depth and texture, as well as climate projection uncertainty and crop model parameterization uncertainty. Study results suggest that varietal choice opens up a large scope for adaptation of future grain maize productivity with important implications for agricultural water use. Assuming that no mitigation measures are taken (RCP8.5), the cultivation of late-maturing varieties in combination with earlier sowing can be considered a suitable adaptation choice, even allowing for increasing yield levels until mid-century. However, with this adaptation choice, irrigation water demands could be expected to increase by up to 40% until the end of the century. While absolute estimates of irrigation water demands are strongly dependent on soil depth (and to a much smaller degree on soil texture), change signals of irrigation water demands were largely unaffected by variation in soil parameters. However, estimates of future changes in irrigation water demands are subject to large uncertainties originating from climate projection uncertainties, implying possible increases in irrigation water demands between <10% and>60%. Increases in irrigation water demands could be constrained by cultivating early-maturing varieties at the expense of lower production potentials. Selection and breeding efforts steered towards early varieties with extended grain filling duration may help to increase yield potentials.

Evaluating the impacts of water resources technology progress on development and economic growth over the Northwest, China.

Water technologies have become new solutions to water scarcity and could play an increasingly crucial role in the future. However, theoretic and empirical studies on the economic effect of water technologies which incorporate water resources into a sustainable economic growth model remain scarce in northwest China. This article attempts to build a water technology endogenous model based on “learning by doing” theory to identify the mechanisms of water technologies affect economic growth due to changing water consumption. Considering the case of Northwest China in this empirical research, we apply the stochastic production frontier model by using panel data from 1996 to 2017. The results shows that progress in water technologies has indeed increased GDP growth and the current level of water technologies is not a key factor in eliminating the constraints of water resources. In addition, water scarcity still constrains economic growth in Northwest China and progress in water science and technology is the main power of all water technologies. Finally, the speed of water science and technology slows as the amount of water consumption increase and the impact of water technical efficiency on economic growth depends on water institutions of different areas. This study may enhance the policy relevance of water technological governance and economic growth transformation, which were beneficial for informing policies towards sustainable water resource utilization in northwest China.

The Drag Effect of Water Resources on China’s Regional Economic Growth: Analysis Based on the Temporal and Spatial Dimensions

Studying the influencing factors of the drag effect of water resources and its temporal–spatial variation can help governments to solve the problem of water resource constraints on the economic growth of different regions. Based on Romer’s hypothesis, this paper uses panel data to empirically analyze the drag effect of water resources in China’s 31 provinces from 1987 to 2017. The research shows that: (1) Water resources have certain constraints on the economic growth of each region. Regional economic growth has declined by 0.23% (eastern), 0.07% (western), 0.43% (central) and 0.09% (northeastern) annually. (2) In provinces with rapid labor growth, water resources have a greater impact on economic growth. In provinces with low labor growth rates, the drag effect of water resources on economic growth is affected by the capital stock of the region. (3) Through the analysis of the water drag effect in different time periods, this paper finds that in some periods, the government’s mobilization of water resources for the economic growth in some regions will not only promote the transfer of labor between regions, but also cause changes in the regional water resources. According to the results of this paper, the following conclusions can be drawn: (1) It is necessary to vigorously develop water-saving agriculture, improve technical efficiency, and reduce the strong dependence of economic growth on water resources in the provinces which has a strong water drag effect on economic growth; (2) Provinces with moderate water resource constraints should take the lead in deploying strategic emerging industries, and accelerate the development of the tertiary industry; (3) Provinces with weakly water resource restrictions can promote the development of capital-based industries. Not only can the development of the economy be rational, but it can also reduce the economy’s dependence on resources, thereby achieving the sustainable use of water resources and sustainable economic growth.

China's Sandy Land Consolidation Engineering and Regional Agricultural Sustainable Development Practice under Water Resource Constraint: Case Study of Yulin City in Shaanxi Province, China

China's Sandy Land Consolidation Engineering and Regional Agricultural Sustainable Development Practice under Water Resource Constraint: Case Study of Yulin City in Shaanxi Province, China

Farmer adaptation to reduced groundwater availability

The sustainability of agriculture in the American West depends on the capacity of farmers to adapt to water resource constraints. Most US studies of agricultural adaptations measure farmers’ willingness to adopt various water use reduction strategies, meaning we have little empirical data on which strategies farmers implement and how these decisions impact their farms. We use survey data from 265 farmers in southeastern Idaho who, beginning in 2016, were required to cut annual groundwater withdrawals by 4%–20% to identify (1) the adaptation practices farmers implemented; (2) how reported crop yields and farm income were impacted; and (3) how adaptation practices varied by farm and farmer characteristics. We found the most commonly used adaptations were reduced spending, installation of more efficient irrigation systems or less frequent watering, and changing crop rotations. Farmers reported losing on average 7.6% of their yield and 8.4% of their income over the first two years of the water cuts. We found no systematic variation based on specific farm or farmer characteristics. Drawing on these results and prior research, we present a typology of adaptation categories intended to inform future research, allow comparisons to adaptation strategies elsewhere, and assist policymakers in designing effective policy interventions.

Life Cycle Water Use for Oxy Fuel Combustion Power Generation with CO2 Capture and Storage

The water scarcity is becoming a growing concern. Regarded as a potential CO emission mitigation technology for coal-fired power plants, oxy-fuel combustion, a typical CCS technology, theoretically consumes a large amount of water, which increases the severity of the water scarcity. Therefore, revealing the water use of oxy-fuel coal-fired power plants is of great importance for the deployment of CCS technologies under water resource constraint in the future. In this respect, the aim of this study is to evaluate the life cycle water use of oxy-fuel CO capture, transport and storage via a 600 MW coal fired oxy-fuel power plant in China. By using a tiered hybrid life cycle assessment, both direct and indirect water use are calculated. Results show 22.9L H O/kg of CO and the oxy-fuel power plant stage dominates the total water use, while the water intensity for power generation is calculated as 3233.3 L H O/MWh, which is higher than the conventional power plants. Sensitivity analysis is performed in this research and indicates that the variation of tap water use affects the water intensity immensely. Furthermore, the use of the membrane method for air separation decreases the overall water use 14.21% respectively. China is continually increasing its efforts to reduce carbon emissions due to both domestic and international pressure. Hence the development and implement of the CCS technology is of great urgency. At the end of this study possible solutions such as using wasted or discarded wind power for the separation of oxygen to minimize water use in oxy-fuel power plant stage are put forward.

Water resource assessment, gaps, and constraints of vegetable production in Robit and Dangishta watersheds, Upper Blue Nile Basin, Ethiopia

The vast majority of farmers in sub-Saharan Africa depend on rainfed agriculture for food production and livelihood. Various factors including but not limited to rainfall variability, land degradation, and low soil fertility constrain agricultural productivity in the region. The objectives of this study were to 1) estimate the water resources potential to sustain small-scale irrigation (SSI) in Ethiopia during the dry season so as to expand food supply by growing vegetables, and 2) understand the gaps and constraints of vegetable production. The case studies were conducted in the Robit and Dangishta watersheds of the Upper Blue Nile Basin, Ethiopia. To document farmers’ cropping practices, field-level data were collected from 36 households who had been cultivating tomato (Solanum lycopersicum L.) and onion (Allium cepa L.) during the dry season (November – April). Two components of the Integrated Decision Support System (IDSS) - the Soil and Water Assessment Tool (SWAT) and Agricultural Policy Environmental eXtender (APEX) – were respectively used to assess impacts of SSI at the watershed and field-scale levels. Results suggest that there is a substantial amount of surface runoff and shallow groundwater recharge at the watershed scale. The field-scale analysis in the Robit watershed indicated that optimal tomato yield could be obtained with 500 mm of water and 200 to 250 kg/ha of urea applied with 50 kg/ha of diammonium phosphate (DAP). In Dangishta, optimum onion yield can be obtained with 400 mm of water and 120 to 180 kg/ha of urea applied with 50 kg/ha of DAP. The field-scale simulation indicated that the average shallow groundwater recharge (after accounting for other groundwater users such as household and livestock use) was not sufficient to meet tomato and onion water demand in the dry season (October to April). The field-scale analysis also indicated that soil evaporation attributed a significant proportion of evapotranspiration (60% for onion and 40% for tomato). Use of mulching or other soil and water conservation interventions could optimize irrigation water for vegetable production by reducing soil evaporation and thereby increasing water availability in the crop root zone.

What should be the future industrial structure of the Beijing-Tianjin-Hebei city region under water resource constraint?An inter-city input-output analysis

Abstract Water scarcity is one of the greatest challenges to the coordinated development of the Beijing-Tianjin-Hebei (BTH) city region. This study thus investigates the optimized industrial structure and potential benefits of the BTH city region under the water resource constraint by developing a multi-city and multi-objective optimization model. The results verify that benefits in terms of economic growth and water savings are simultaneously achievable through the industrial restructuring, with an economic growth potential of Chinese Yuan (CNY) 302 billion and potential water savings of 8760 million m3. To achieve this “optimized” status, the output scale of the BTH city region should increase by CNY 1246 billion and the regional industrial structure be optimized by restricting the scale of water-intensive sectors and supporting technology-intensive industries. This study also emphasizes the significance of agricultural water use control in Hebei for water saving and suggests reconsidering the traditional positioning of Hebei as a national grain production base. The results provide useful information for the adjustment of the industrial structure of the BTH city region and are thus conducive for relevant policy formulation.

The Impacts of Water Pricing and Non-Pricing Policies on Sustainable Water Resources Management: A Case of Ghorveh Plain at Kurdistan Province, Iran

As with other regions of Iran, due to excessive extraction of groundwater for intense agricultural activity, Ghorveh plain, a water-scarce irrigation district in the west of Iran, has faced a serious water crisis during the last decade. The present study investigates the impacts of two scenario policies, namely, non-price policy (as a supply-oriented policy) and water pricing policies (as a demand-oriented policy) on agricultural sector of Ghorveh Plain, using positive mathematical programming (PMP). The model was calibrated by using farm-level data for the crop years in 2016–2017. Our findings indicate that applying water supply constraint policy will change the land use and cropping pattern to the crops with higher water productivity. The increase of water resource constraints can lead to the increase of water economic return which indicates a rising value of water resources shortage, warning the producers of the agriculture sector to allocate water to the crops with higher economic value under the water resources shortage conditions. In addition, the findings underline that in a situation where the price of irrigation water is low due to the low elasticity of water demand in the agriculture sector, formulating the economic instruments such as rising water prices does not solely suffice to achieve sustainable water resource management. However, mixed scenarios emphasized that the water distribution policies should be aligned with the increases in water cost.

Exposure of urban food–energy–water (FEW) systems to water scarcity

Income and population growth increase demands for commodities such as food, energy, and water in cities. Water resources are used outside of cities to produce the food and energy goods that are eventually consumed in cities. In this way, urban water scarcity is impacted directly by local water shortages and indirectly by water scarcity in locations along the supply chain. Both direct and indirect water scarcity risks have important implications for urban water, food, and energy security. In this study, we develop a novel metric of the urban food–energy–water (FEW) nexus that quantifies both direct and indirect water scarcity exposure to urban areas. We quantify and visualize direct and indirect FEW water scarcity for 69 metropolitan statistical areas within the continental United States. We show that cities typically import commodities from nearby locations with similar water resource constraints, and generally have similar local and indirect water scarcity. In particular, cities in the western United States have scarce local water resources and also import commodities from other water-scarce western locations. This study improves our understanding of water scarcity exposure of critical food and energy resources in U.S. urban areas, enabling policy makers to improve the reliability of urban food and energy receipts.

Coupling the maximum overlap discrete wavelet transform and long short-term memory networks for irrigation flow forecasting

Many countries are suffering from water resource constraints due to rising demands from different water-consuming sectors and a changing climate. In some countries, such as Spain, operators of agricultural irrigation are under increasing pressure to improve efficiency. Accordingly, accurate forecasts of water demand are a pre-requisite for the successful implementation of water resources planning and management tools in irrigated areas. However, forecasting approaches based on traditional neural networks have challenges to capture temporal dependencies that generally characterize irrigation flow time series. In this study, for the first time, a recurrent long short-term memory network (LSTM) was coupled with the maximum overlap discrete wavelet transformation (MODWT) and bootstrap techniques, for accurate and robust irrigation flow forecasting. For comparative purposes, the study also explored the ability of an Artificial Neural Network (ANN), a Least Squares Support Vector Regression (LSSVR), an Extreme Learning Machine (ELM) and a Multi Linear Regression (MLR), to forecast irrigation flow in Palos de la Frontera, an irrigation district located in Huelva (southern Spain), for a one-day lead time. The autocorrelation function and partial autocorrelation function determined the most significant lagged time series of irrigation flow to be used as model inputs. The wavelet-LSTM (W-LSTM) and waveletbootstrap-ANN models (WB-ANN) had the most accurate forecasts, as measured by statistical metrics including the root mean square error (RMSE), mean absolute error (MAE), coefficient of determination (r2), mean relative error (MRE), mean absolute relative error (MARE), Willmott’s index, and Nash-Sutcliffe efficiency index (NASH). In this study, the capabilities of LSTMs, along with the MODWT transform analysis and bootstrap techniques, were benchmarked and could be further explored for forecasting other water resources variables in different climatic regions and for multi-step lead time forecasting.

Factors Associated with Water Service Continuity for the Rural Populations of Bangladesh, Pakistan, Ethiopia, and Mozambique.

Access to continuous water supply is key for improving health and economic outcomes in rural areas of low- and middle-income countries, but the factors associated with continuous water access in these areas have not been well-characterized. We surveyed 4786 households for evidence of technical, financial, institutional, social, and environmental predictors of rural water service continuity (WSC), defined as the percentage of the year that water is available from a source. Multiple imputed fractional logistic regression models that account for the survey design were used to assess operational risks to WSC for piped supply, tube wells, boreholes, springs, dug wells, and surface water for the rural populations of Bangladesh, Pakistan, Ethiopia, and Mozambique. Multivariable regressions indicate that households using multiple water sources were associated with lower WSC in Bangladesh, Pakistan, and Mozambique. However, the possibility must be considered that households may use more than one water source because services are intermittent. Water scarcity and drought were largely unassociated with WSC, suggesting that service interruptions may not be primarily due to physical water resource constraints. Consistent findings across countries may have broader relevance for meeting established targets for service availability as well as human health.

Adaptive management of water resources based on an advanced entropy method to quantify agent information

Abstract Adaptive management is currently an important method to optimize the management of complex water resources systems. Regional water resources adaptive management was conducted based on the advanced theory of a complex system multi-agent model; the state of an agent was tracked and modified by information entropy theory, which was improved by using individual standard deviations. With the goal of optimizing the adaptation of each agent of the region, water resources in the major grain production area of China were managed under the constraints of the total annual available water resources and water use efficiency requirements for 2015 and 2030. By introducing the adaptive water resources management in 2015, the domestic benefits and economic benefits increased by 2.90% and 14.81%, respectively, with respect to observed values. The ecological benefits declined by 3.63%, but ecological water demand was fully satisfied, and the ecological water environment was improved. Given the water use efficiency targets in 2030, applying adaptive management resulted in an increase of domestic, economic, and ecological benefits of 34.29%, 21.14%, and 1.78%, respectively. The results show that the adaptive management method presented can help managers to balance the benefits of various agents to determine the direction of water resources management decisions.

Farm-to-School Programs' Local Foods Activity in Southern Arizona: A Case Study

This analysis applies principles and methods from the U.S. Department of Agriculture (USDA) Local Foods Toolkit to demonstrate the moderating influence of countervailing effects on the economic impacts of local food purchases through farm-to-school programs in Southern Arizona using USDA Farm to School Census data. The analysis applies and expands upon recommendations in the Toolkit, introducing the concept of export substitution and exploring how water resource constraints create tradeoffs for farms through crop-shifting and cropping rotations. The analysis reveals that for fruit and vegetable exporting regions, export substitution can be a major countervailing effect. Furthermore, the analysis examines the usefulness of the Farm to School Census as a secondary data source for estimating the economic impacts of local food activities, allowing us to make recommendations for how the Census could be expanded and supplemented for regional economic applications.

Farm-to-School Programs' Local Foods Activity in Southern Arizona: A Case Study

This analysis applies principles and methods from the U.S. Department of Agriculture (USDA) Local Foods Toolkit to demonstrate the moderating influence of countervailing effects on the economic impacts of local food purchases through farm-to-school programs in Southern Arizona using USDA Farm to School Census data. The analysis applies and expands upon recommendations in the Toolkit, introducing the concept of export substitution and exploring how water resource constraints create tradeoffs for farms through crop-shifting and cropping rotations. The analysis reveals that for fruit and vegetable exporting regions, export substitution can be a major countervailing effect. Furthermore, the analysis examines the usefulness of the Farm to School Census as a secondary data source for estimating the economic impacts of local food activities, allowing us to make recommendations for how the Census could be expanded and supplemented for regional economic applications.

Regional Development in Conditions of Limitation of Water Resources: Correlation Interconnections

The main idea of the article is to study the problem of regional development in the conditions of limited water resources. The subject of the study is theoretical and methodological provisions and applied practical recommendations for the regulation of regional development in the conditions of limited water resources. The purpose of the article is to determine the connection between water supply (water potential) of Ukrainian regions and their specialization in production and trade in the conditions of water resource constraints and determine the further prospects for regional development.