Capita Water Availability Research Articles

The Need to Maintain the Quality of Naturally Pure Water of Sarayu River

Rivers are a link between human life and nature. All the ancient developed cities are situated on the banks of some river or the other ancient civilizations of India have developed on the banks of rivers. The river is helpful in both, flood and drought conditions, works to balance nature by absorbing the flood water inside itself and giving water to animals and humans during drought. In the present scenario, due to the increasing population of cities and the pollution arising from it, the water of rivers is getting polluted rapidly. Many rivers of the country are slowly disappearing and some rivers have water only during monsoon. Our country is slowly moving towards water crisis. To get out of this crisis, we all need a corrective change in behaviour along with scientific remedial system. The per capita availability of water has decreased significantly in the last 75 years. According to one figure, in 1951 the per capita was 5177 cubic meters but in the year 2011 only 1545 cubic meters of water is available per person. According to a study by the National Institute of Hydrology, India will have only 814 cubic meters of usable water per capita in 2025. When we studied the water of Sarayu river, it was found that all the parameters and heavy metals present in the water raised after monsoon are within the processed limit. When the properties of the water of Sarayu river were studied, surprising results came out. All the elements present in the water like calcium, magnesium, chloride, fluoride, alkalinity, nitrate ion, sulphate ion, arsenic and manganese etc. were within the required limits. Desirable limits of calcium, magnesium, chloride, alkalinity, nitrate ion, sulphate ion are 75 mg/l, 30 mg/l, 25 mg/l, 200 mg/l, 200 mg/l, respectively. The maximum values in pre-monsoon were found to be 38.47 mg/l, 26.24 mg/l, 15.9 mg/l, 192 mg/l, 0.20 mg/l and 20.10 mg/l respectively and in post-monsoon its maximum value was found to be 28.86 mg/l, 12.49 mg/l, 17.99 mg/l, 128 mg/l, 1.5 mg/l and 41.30 mg/l, respectively. The desirable limit of arsenic is 0.01, found to be 0.01 at some places in pre-monsoon but found to be nil in post-monsoon.

Ensemble probability distribution of annual runoff for the past 70 years in two main watersheds of China

ABSTRACT Water resources in China, especially in the major basins of the Songhua and Yangtze Rivers, are characterized by uneven distribution both temporally and spatially, leading to notable challenges in per capita water availability. In this study, we investigate the ensemble probability distribution of annual runoff over the past 70 years in two of China's major watersheds: the Songhua River and the Yangtze River. By dividing each basin into several regions from upstream to downstream, based on annual mean discharge as a proxy for annual runoff, we observed a significant correlation between the annual runoff of the control sections and that of the upstream and downstream regions in these large watersheds. Consequently, this study establishes the probability distribution of annual runoff for each region within the basins, anchored on the design annual runoff of the control sections, using the joint bivariate logarithmic normal distribution of two interrelated random variables. Furthermore, we developed a relationship between the conditional probability distribution and correlation diagram data, and a regression equation correlating regional annual runoff with the watershed control section's runoff. This investigation into the historical patterns of runoff over the past 70 years provides a comprehensive understanding of the dynamics in these critical watersheds.

How does virtual water influence the water stress pattern in Africa? A research perspective from the perspectives of production and trade

Northern Africa has become the first region in the world to exhaust its water resources, with a 40 % decrease in per capita water availability south of the Sahara over the past decade. While adjusting production structures and consumption can regulate the supply-demand dynamics of water resources, the extent of the impact of virtual water-induced pressure on both the regional and national levels in Africa remains largely understudied. Applying the standard Penman formula, this research calculates the water footprint of eight cereal crops in 54 African countries from 1990 to 2021. By integrating corresponding data on cereal trade, the study analyzes changes in virtual water stress. The findings indicate a decline in the per-unit production and consumption water footprints for African cereals. However, the continuous expansion of cultivation areas contributes to a rising water stress. In comparison to 1990, the water stress for soybeans, sorghum, rice, maize, and cassava increased by 149.72 %, 146.88 %, 133.89 %, 123.30 %, and 90.8 %, respectively, in 2021. Only barley showed a reduction in water stress by 23.22 %. The study underscores the growing interconnectedness of virtual water trade (VWT) among African nations from 1990 to 2021, leading to a more balanced trade distribution. VWT has reduced water stress by 7.65 %, 2.08 %, and 1.8 % in Western, Central, and Northern Africa, respectively, while increasing pressure in Southern and Eastern Africa by 10.51 % and 1.01 %. The flow of virtual water in Africa is most influenced by spatial proximity, primarily occurring between adjacent countries or regions. Forecasts for water stress under the five scenarios of SSPs-RCP8.5 have been conducted, revealing a continuous increase in water stress across Africa. Furthermore, analysis of the SSP2-RCP8.5 scenario indicates that by 2030 and 2040, African cereal crops are projected to face virtual water resource stress increases of 7 % and 18.76 %, respectively, compared to 2020 levels. During the same period, Sierra Leone is anticipated to experience a growth rate in virtual water stress of approximately 1903.38 %. Consequently, altering crop cultivation structures and enhancing VWT are poised to alleviate water resource pressure, promoting the scientific management of agricultural water resources in Africa.

Evaluation of gridded precipitation data in water availability modeling in CONUS

Water availability estimates are affected by the quality of data used. In this study precipitation data from meteorological forcing datasets specifically compiled for large-scale hydrological modeling are evaluated over the Conterminous United States (CONUS). The performance of the datasets was evaluated using Pearson Correlation (r), Nash Sutcliff Efficiency (NSE), Percent Bias (PBIAS), and Kling Gupta Efficiency (KGE) criterion. Three observation-based gridded precipitation data from the Inter-Sectoral Impact Model Intercomparison Project – ISIMIP (EartH2Observe, WFDEI and ERA-Interim data Merged and Bias-corrected for ISIMIP (EWEMBI), WATCH Forcing Data methodologyapplied to ERA-Interim data (WFDEI), and WFDE5 over land merged with ERA5 over the ocean (W5E5)) and one regional dataset (GRIDMET) were compared. The datasets were compared using more than 3300 gage precipitation observations. For grid-level comparisons, the Climate Prediction Center's Unified gage-based gridded precipitation dataset (CPC) was used as a reference dataset after verification with gage observations. The grid-to-grid comparison was made on daily, monthly, annual, and seasonal time steps. Grid runoff and discharge were simulated using the Community Water Model (CWatM) model. The flow estimations using the datasets were compared with CPC estimations and with more than 900 discharge observations distributed over the nine climate regions of CONUS. Furthermore, the per capita water availability was estimated and compared. In comparison with gage precipitation observation, CPC had superior performance, followed by GRIDMET. CPC resulted in daily KGE, NSE, and r above 0.5, and PBIAS within 25 % in 79 %, 69 %, 87 %, and 90 % of the stations, respectively. Grid-to-grid precipitation comparisons resulted in overall comparable performance between the datasets. In grid discharge estimation, GRIDMET (median KGE = 0.68) had the highest correlation with CPC. WFDEI, W5E5, and EWEMBI show close performance to each other in estimating grid discharge with median KGE values of 0.43, 0.25, and 0.45 respectively. The performance of the datasets as compared to observed stream flow gages also showed comparable performance with above zero KGE in 73, 56, 71, 60, and 70 stations by GRIDMET, EWEMBI, W5E5, and WFDEI, and CPC respectively. In estimating water availability per capita, W5E5 showed an overestimation as compared to ISMIP datasets. The estimations from CPC and GRIDMET were close to each other. This study serves as a valuable resource for guiding the selection of a suitable dataset for large-scale modeling over the CONUS. By providing performance information for the compared datasets, it assists in making informed data selection and contributes to our understanding of how the selection of input datasets affect water availability modeling.

Impact of Climate Change on Water in Pakistan

“The water issue is critically related to climate change. People say that carbon is the currency of climate change. Water is the teeth.” Jim Yong Kim, Former President, World Bank
 1. INTRODUCTION
 Water is the prime channel through which the impacts of climate change on the world’s ecosystems and livelihoods will be felt. Pakistan is already a water-stressed country, ranking 14 among the 17 ‘extremely high water risk’ countries. Climate change in the form of rising temperatures and extreme and less predictable weather patterns are projected to affect patterns of rainfall, snowmelt, river flows, groundwater and water quality in Pakistan. This can lead to an increase in both inter- and intra-country disputes over water sharing arrangements.
 Over the last two decades, Pakistan has been ranked among the top 10 most vulnerable countries of the world to climate change, with 10,000 fatalities due to climaterelated disasters and financial losses amounting to about $4 billion from 173 extreme weather events. The country is already facing climate-related threats to water resources as is evident from the change in monsoon patterns, receding glaciers, rising temperatures and recurrence of floods and droughts. The floods of 2010, 2011 and 2012 not only incurred human cost but also economic costs, resulting in economic growth on average at a rate of 2.9 percent instead of its potential rate of 6.5 percent. Prolonged droughts in Tharparkar in Sindh and Balochistan also caused loss to human life and livelihoods. Since mid of June 2022, Pakistan has been affected by worst floods caused by record monsoon rains and melting glaciers, costing the economy over US$30 billion. Over 33 million people have been affected out of total population of 222 million, and around 1,400 people have been killed. One-third of the country is under water, with over 80 districts (out of 160 districts) in the country having been officially notified as ‘calamity hit’ – 31 in Balochistan, 23 in Sindh, 17 in KP, 06 in GB and 03 in Punjab. The paper aims to address the impact of climate change on water systems and people.
 2. MAIN SOURCES OF WATER IN PAKISTAN
 With 2.8 percent of the global population, Pakistan accounts for 0.5 percent of global renewable water resources. In other words, with the fifth largest population in the world, Pakistan ranked 36 out of 184 countries in total renewable water resources compared to India’s rank at 8 th and Bangladesh’s at 12th in 2017.
 Pakistan is a ‘water scarce’ country with a per capita water availability of less than 1,000 cubic metres. In 1951, Pakistan had an abundance of water with 5,260 cubic metres per capita, however, the country became ‘water vulnerable’ in 1981 with less than 2,500 cubic metres of water availability per capita to ‘water stress’ in 1991 with less than 1,700 cubic metres of water (see figure 1). By 2025, Pakistan could face droughts as its per capita water availability is going to become ‘absolutely scarce’ with less than 500 cubic metres.
 Indus Basin accounts for 96 percent of total available freshwater resources in Pakistan and around 80 percent of the country’s freshwater originates from outside the country, making it extremely risky and vulnerable (see Table 1). Glacier melt, snow melt and rainfall runoff account for 10 percent, 55 percent and 35 percent of total water in the upper Indus respectively. Over 85 percent of total water in the Indus originates from the Upper Indus and is shared between Pakistan (53 percent of the total area of Indus), India (33.5 percent), China (6.7 percent) and Afghanistan (6.3 percent). Stream flow in the upper Indus basin is highly seasonal: approximately 80 percent of the volume of annual stream flow in the tributaries of the upper Indus basin occurs during the summer months of midJune to mid-September.

Quantifying the Long-Term Performance of Rainwater Harvesting in Cyclades, Greece

South European and Mediterranean countries traditionally suffer from water scarcity, especially the regions around the Mediterranean. In Cyclades, the effects of drought have historically been observed and tackled with small-scale applications, with the most efficient method being rainwater harvesting (RWH). RWH is an inherent aspect of the local population’s culture and architecture, since most houses have built-in water tanks and flat roofs to harvest as much rainwater as possible. In recent decades, the increase in local population and tourism have added additional stress to the limited water resources of the Cycladic islands. To overcome water shortages, most of the islands are equipped with desalination plants. Despite the use of these plants, RWH is still a vital source of water that is free and has zero carbon footprint. Thus, it is important to compare, assess and quantify the performance of this traditional water conserving method as a key water source for the islands’ water resources management, today and for the coming decades. In this research, we investigate and quantify the future performance of rainwater harvesting applications and their contribution to continuous, sustainable, and climate-resilient water supply. The results show a decrease in rainwater harvesting potential in most of the islands, as well as the negative effect of touristic activity on per capita water availability on the islands.

Sustainable Water Harvesting for Improving Food Security and Livelihoods of Smallholders under Different Climatic Conditions of India

In India, the per capita availability of water is projected to be 1465 m3 and 1235 m3 by the years 2025 and 2050, respectively, and hence, India would be a water-stressed country as per the United Nations’ standard of less than 1700 m3 per capita water availability. India is predominantly an agricultural-dominant country. Rainfed agriculture in the country contributes 40% of food grain production and supports half of the human population and two-thirds of the livestock population. The country has 15 different agro-climatic zones, and each agro-climatic region has its own constraints of water availability and management along with the potential for their optimum utilization. Such situations warrant the formulation of regional-level strategies. Efforts were made to integrate and evaluate the feasibility of water harvesting and its utilization at twelve different sites representing six different agro-climatic conditions spanning pan India. It was found that water harvesting through tanks/ponds is a feasible approach and can increase the crop production as well as diversification. The results reveal that the range of crop diversification index increased from 0.49–0.85 to 0.65–0.98; the crop productivity index increased from 0.28–0.66 to 0.66–0.90; the cultivated land utilization index increased from 0.05–0.69 to 0.34–0.84; and the crop water productivity index increased from 0.20–0.51 to 0.56–0.96, among other production and diversification indices, due to additional water availability through rainwater harvesting intervention. Moreover, the gross return increased from INR 43,768–704,356 to INR 220,840–1,469,108 ha−1, representing a 108 to 400% increase in the returns due to the availability of water. The findings of this study suggest that the water harvesting in small ponds/tanks is economical and feasible, requires less technological intervention, and increases crop diversification in all the studied agro-climatic conditions, and hence, the same needs to be encouraged in the rainfed areas of the country.

Novel Vertical Flow Wetland Filtration Combined with Co-Zeotype Material Based Catalytic Ozonation Process for the Treatment of Municipal Wastewater

Municipal wastewater treatment to recycling level is an important means to conserve water resources. Untreated wastewater leads to a reduction in per capita availability of water and an increase in environmental pollution. Therefore, in the current study, a filtration process based on Typha Angustifolia planted vertical flow wetland and Rice husk (VFCW) in combination with catalytic ozonation based on Cobalt loaded zeotype catalyst was used for the first time to treat municipal wastewater. The results at optimized conditions show that about 89%, 93%, and 97% of BOD5, COD, and TKN respectively were removed based on combined VFCW/Co-zeotype/O3 processes. More than 90% elimination of heavy metals including Cr, Cu, Cd, Fe, Ni, and Zn was also observed. Hence, it is concluded that the VFCW/Co-zeotype/O3 process has potential as an alternative to conventional treatment for municipal wastewater treatment.

GLOBAL WATER SCARCITY DUE TO CLIMATE CHANGE AND ITS CONSERVATION STRATEGIES WITH SPECIAL REFERENCE TO INDIA : A REVIEW

The strategic importance of fresh water for global water and food security will probably intensify under climate change which worsen the situation as it leads to increased frequency and intensity of climatic extremes such as flood, drought, cyclone, heat/ cold waves, alteration in water cycle, water resources depletion, increased variability of precipitation, salt water intrusion in aquifers, increasing irrigation demand, decreasing soil moisture and rapid evaporation of surface water and many more. This review provides an insight about climate change and its impact on quantity and quality of water, water scarcity on a global scale with emphasis on Indian water resources, its availability and conservation strategies to mitigate water scarcity. Global warming resulting in climate change is expected to account for about 20% of the global increase in water scarcity. Global water consumption has increased six fold in last century and in coming decades is expected to grow rapidly. By 2025, 1.8 billion people will be living in countries or regions with absolute water scarcity, and two-thirds of the world's population could be living under water stressed conditions. African continent is the worst affected by the scarcity of water. The gross per capita water availability in India will decline from about 1820 m3 per year in 2001 to as low as about 1140 m3 per year in 2050. It is estimated that the country would need 1180 billion cubic meters (BCM) of water annually by 2050. So, there is an urgent need of sustainable utilization of water resources, formulation of climate adaption strategies, making the people and government aware about shrinking water resources as well as taking urgent action for conservation and harvesting of water at local, national and global scale.

Water Federalism, Tribunalization of Water Justice and Hydro-Politics: India’s Inter-State River Water Disputes Act at 65 Years

India’s water federalism is at a crossroads. It is a unique two-tier system that has the constitutional and enabling provisions for water management and inter-state water dispute resolution as its base. These support the tribunal system that adjudicates inter-state river water disputes and administers water justice. More than six decades have elapsed since its establishment. At the same time, during this period, the per capita water availability has fallen drastically. India is now one of the world’s most water-stressed countries. Water disputes between States are becoming more animated and highly volatile. This article examines water federalism in India in terms of two questions: 1) Should water be transferred from the State List to the Concurrent List? 2) Should India persist with the tribunal system or replace it with the judicial process at the Supreme Court level? The first assumes importance as India persists with the river linking project. The second is relevant because the Inter-State River Water Disputes Act is almost 65 years old. In 2016, India’s Supreme Court re-wrote the law, and, more recently, the Union Government sought to revamp the Inter-State River Water Disputes Act through amendments. All these impel the need to re-look the idea of water federalism as it operates in India in its entirety.

Sustainability of the Water-Energy-Food Nexus in Caribbean Small Island Developing States

The sustainability of small island developing states (SIDS) of the Caribbean is fragile because of island size and topography, limited resources, population growth, natural disasters, and climate change. Current and projected sustainability in 2050 were assessed within the framework of the water–energy–food (WEF) nexus for 10 of 16 SIDS with the best databases. Values for each WEF sector below either Falkenmark indicators or regional averages were considered unsustainable (failing) for that sector. Overall, SIDS were considered unsustainable if they failed at least two of three sectors. Projected water sustainability for 2050 was based on population growth and climate change effects on precipitation and per capita water availability. All SIDS failed the food sector, and four failed the energy sector. Water was considered the ultimate control for long-term sustainability. Five SIDS currently fail the water sector, but all but the largest two SIDS are likely to fail this sector by 2050. The role of poor governance and associated lack of long-term planning for population growth, disasters, and climate change, adaptative management strategies, infrastructure investment with an emphasis on nature-based solutions, decentralized energy grids emphasizing renewable energy, and local food production are clearly impediments for reaching sustainability goals for Caribbean SIDS.

Standardization of fertigation scheduling in broccoli (Brassica oleracea var italica)

Efficient use of water and fertilizer is extremely critical to sustain the agricultural production, in the context of declining per capita land and water availability, pollution and increasing cost of fertilizers. A field experiment was conducted at Vegetable Research Centre of G.B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, India during the rabi 2016-17 and 2017-18 to study the effect of fertigation with levels and scheduling on growth, yield and economics of broccoli (Brassica oleracea var italica). The experiment was laid out in two factorial RBD with one additional treatment consisting of five fertigation levels and three fertigation scheduling along with one control (soil application of RDF with flooding) replicated thrice. The outcome of study revealed that fertigation of broccoli with water soluble fertilizer gave significantly higher plant growth, net return and benefit cost ratio as compared to the soil application of RDF with flooding (control). Fertigation treatments registered a significantly higher yield of 13.74 t/ha and it was higher by 15.96% over the conventional method of fertilization (11.85 t/ha).

A coupled human–natural system analysis of freshwater security under climate and population change

Limited water availability, population growth, and climate change have resulted in freshwater crises in many countries. Jordan's situation is emblematic, compounded by conflict-induced population shocks. Integrating knowledge across hydrology, climatology, agriculture, political science, geography, and economics, we present the Jordan Water Model, a nationwide coupled human-natural-engineered systems model that is used to evaluate Jordan's freshwater security under climate and socioeconomic changes. The complex systems model simulates the trajectory of Jordan's water system, representing dynamic interactions between a hierarchy of actors and the natural and engineered water environment. A multiagent modeling approach enables the quantification of impacts at the level of thousands of representative agents across sectors, allowing for the evaluation of both systemwide and distributional outcomes translated into a suite of water-security metrics (vulnerability, equity, shortage duration, and economic well-being). Model results indicate severe, potentially destabilizing, declines in freshwater security. Per capita water availability decreases by approximately 50% by the end of the century. Without intervening measures, >90% of the low-income household population experiences critical insecurity by the end of the century, receiving <40 L per capita per day. Widening disparity in freshwater use, lengthening shortage durations, and declining economic welfare are prevalent across narratives. To gain a foothold on its freshwater future, Jordan must enact a sweeping portfolio of ambitious interventions that include large-scale desalinization and comprehensive water sector reform, with model results revealing exponential improvements in water security through the coordination of supply- and demand-side measures.

Virtual Water and Its Share in Per-capita Water Availability (Case Study of Ethiopia)

Today, the security, stability and environmental sustainability of developing nations are threatened by the growing global water crisis. This crisis is partly due to water governance. Improving water infrastructure must be a priority, as water conservation and efficiency are key components of sustainable water management. The idea of virtual water import/export as a method to ease the pressure on the available domestic water resources is a concern for sustainable water management. This concept of virtual water further extends the scope of water resources management beyond the boundary of natural watershed. Since the water use of a given watershed can be influenced by water use outside of the watershed through virtual water transfers, it is not sufficient to confine the water resources management to the basin or catchment scale. The role of virtual water in bridging the gap between supply and demand of water is underestimated. Although invisible, the importance of ‘virtual water' can be an effective means for water-scarce countries to preserve their domestic water resources. This paper examines the virtual water concepts in relation to per capita water availability taking 2000 to 2015 years as the period of analysis. The results of the study showed that the total exported and imported virtual water in the period of analysis in Ethiopia is 113 billion m³ and 10.9 billion m³ respectively. These values showed that Ethiopia is a net virtual water exporter. The maximum and minimum per-capita water availability during the analysis period was 2590 m³/cap/year and 1740 m³/cap/year respectively. These results indicated no water stress in the period of analysis.

Application of System Thinking Causal Loop Modelling in understanding water Crisis in India: A case for sustainable Integrated Water resources management across sectors

India is one among the high risk countries susceptible to water stress and as a result of exponential population growth, industrialization and rapid urbanization the per capita water availability is fast diminishing and adding to this climate change is further expected to exacerbate the problem resulting in more frequent and prolonged drought. Water is considered to be a wicked problem and hence relying on a linear and reductionist approach may no longer seems relevant in solving such complex systems. This paper adopts a system thinking principle to understand various water management challenges across sectors. System thinking has its roots in mental models and has been evolving and increasingly being used to understand Complex Dynamic Systems. Based on a systematic review of literature, the present study has developed a series of Causal Loop Diagrams (CLDs) capturing key variables pertaining to water sector. CLDs are believed to create a broader and holistic understanding of the water management challenges by clearly exhibiting the relationship between the key variables. The proposed CLDs serve as a decision making tool to understand the challenges of integrated water resources management through the complex interactions of the variables between balancing and reinforcing loops. The CLDs highlights the existing water related challenges in India and proposes a pathway for sustainable management of water resources across agriculture, industry and domestic sectors. Though the CLD discussion in this paper is based on Indian scenario, it holds good for any developing countries context.

Specification a Model for Study of Sustainable Development

In the year 2025 the per capita water availability will decrease to 1 50 liters per day in the best case for communities near an aquifer. The water situation will worsen as population density deepens and the shortage exacerbates unhealthiness, the main cause of death in children with hydrotransmitted diseases. Such a scenario requires a reconceptualization theoretical approaches that allow public policies, the book s environmental, public opinion and social work. In this sense, the objective of the present work is to expose the water situations to conceptualize them from the thought of Enrique Leff (2002; 2004; 2008)and analyze its transformation into a public agenda. The understanding of the existing between the water situations, public opinion, political initiatives, scientific diagnoses, tecno-hydrologic innovations and media coverage will be crucial for social work professionals in the near future.

Determinants of Households’ Budget Allocation to Water Consumption: Evidence from Urban Pakistan

Per capita availability of water is a serious challenge for Pakistan, like other countries. The objectives of this study are to investigate the different sources of water supply use by Pakistan’s urban households, their willingness to pay and modelling the determinants of the households’ budget allocation for water consumption. The study employed Pakistan Social and Living Standards Measurement (PSLM) 2015–2016 data set, which revealed that more than 60 per cent of households rely on piped water. The result of the variable filtration plant shows that urban households take less care of their health because the tendency of filtered water use is low. The regression result shows negative effect of per capita income, and positive effect of square of per capita income reflects that measures to accelerate income will help to increase budget allocation for water supply at the households’ level. The findings call for accelerating the water filtration plants, water availability in tap and higher incomes while controlling the population size and shared common washroom can help to save water in the case of urban Pakistan.

Challenges and Prospects of Using Treated Wastewater to Manage Water Scarcity Crises in the Gulf Cooperation Council (GCC) Countries

The Gulf Cooperation Council (GCC) countries are located in the driest part of the world with an annual per capita water availability of 500 m3 compared to the world average of 6000 m3. Agricultural water demand, which is more than 80% of the total water consumption, is primarily met through the massive exploitation of groundwater. The enormous imbalance between groundwater discharge (27.8 billion m3) and recharge (5.3 billion m3) is causing the excessive lowering of groundwater levels. Therefore, GCC countries are investing heavily in the production of nonconventional water resources such as desalination of seawater and treated wastewater. Currently, 439 desalination plants are annually producing 5.75 billion m3 of desalinated water in the GCC countries. The annual wastewater collection is about 4.0 billion m3, of which 73% is treated with the help of 300 wastewater treatment plants. Despite extreme water poverty, only 39% of the treated wastewater is reused, and the remaining is discharged into the sea. The treated wastewater (TWW) is used for the landscape, forestry, and construction industries. However, its reuse to irrigate food and forage crops is restricted due to health, social, religious, and environmental concerns. Substantial research evidence exists that treated wastewater can safely be used to grow food and forage crops under the agroclimatic conditions of the GCC countries by adopting appropriate management measures. Therefore, GCC countries should work on increasing the use of TWW in the agriculture sector. Increased use of TWW in agriculture can significantly reduce the pressure on freshwater resources. For this purpose, a comprehensive awareness campaign needs to be initiated to address the social and religious concerns of farming communities and consumers. Several internal and external risks can jeopardize the sustainable use of treated wastewater in the GCC countries. These include climate change, increasing costs, technological and market-driven changes, and regional security issues. Therefore, effective response mechanisms should be developed to mitigate future risks and threats. For this purpose, an integrated approach involving all concerned local and regional stakeholders needs to be adopted.

How High-Quality Urbanization Affects Utilization Efficiency of Agricultural Water Resources in the Yellow River Basin under Double Control Action?

To promote the high-quality development of the Yellow River Basin, the total amount and intensity of agricultural water must be controlled. Further speaking, an urbanization development system should be established that is compatible with water resources and the water environment. We adopted the stochastic frontier analysis model to measure the agricultural water utilization efficiency of the Yellow River Basin from 2007 to 2017. We also adopted the dynamic panel difference generalized method of moments (GMM) and system GMM models to verify the driving factors, in which population urbanization, economic urbanization, and equilibrium urbanization levels were selected as the key variables. The results show that the overall efficiency of agricultural water utilization maintained a steady upward trend during the research period. The spatial differentiation was generally characterized by higher efficiency levels in the eastern region and lower levels in the western region. The variation coefficient of water utilization efficiency showed a downward trend in general, which indicates a space spillover effect. Agricultural water utilization efficiency continued to converge from 2007 to 2017, and the upper reaches area converged relatively more quickly. Regarding the influencing factors, the population urbanization, economic urbanization, balanced urbanization, crop planting ratio, and rice planting ratio had negative effects on agricultural water utilization efficiency. Urbanization did not positively affect agricultural water use efficiency as the related theories, so urbanization quality and urban–rural integration should be paid more attention. However, technology innovation was significantly positive in agricultural water utilization efficiency. The influencing factors of per capita water availability and annual precipitation did not pass the significance test. Therefore, the government should vigorously promote the development of high-quality new-type urbanization, scientifically formulate the scale and speed of urbanization, strengthen the urban, rural, and industrial integration, and promote the adjustment of planting structures and agricultural deep processing.

Tourism and inequality in per capita water availability: is the linkage sustainable?

This paper shows the bilateral association between tourism development and inequality in per capita availability of water. The study is conducted on the countries with high tourism receipt, and thereafter, this study shows whether the directions of tourism development in these countries are going to be sustainable or not. In order to achieve this, we have used tourism investment and tourism receipt as two indicators of tourism development and have assessed their differential impacts on the disparity in water availability by applying DOLS and causality analysis approach. Empirical results show long-run impact of tourism on inequality in per capita availability of water, along with the presence of bidirectional causal association among the tourism development and inequality parameters. This study further reveals the impact of tourism on the regional disparity in distribution of water that can appear due to the differential approach taken toward tourism development. Based on study outcomes, several policy directions where offered for the investigated blocs.