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AbstractSeedlings of 95 greenhouse-grown interior Douglas-fir half-sibling families originating from four breeding zones were subject to overwatering and periodic underwatering and compared to an optimally watered control (15 per family = 1425 seedlings total). Averaged over all trees, annual height was reduced by 4% and 11% compared to controls for overwatering and periodic underwatering, respectively. Family overwatered seedling height was 135–75%, and underwatered height was 100–75% of their respective control heights. Shorter families under stress grew like their control compared to taller families, but this was reversed in taller families when the watering conditions were ideal. A survival analysis indicated that after 30–50 days without water, family survival varied from 25% to 90%, and most trees died after 60 days. The breeding zone had little effect on the tolerance to suboptimal water or survival during complete water withdrawal and did not interact with watering treatments. Family traits for tolerance to overwatering favoured root biomass, traits for underwatering favoured reduced stem biomass, especially in ratio to roots, and traits for survival favoured belowground biomass over aboveground biomass. No tradeoffs between tolerance to over- and underwatering were found. Some families did well in all three conditions and some in one or the other. The study results suggest that variation in family growth and survival to suboptimal watering partly relate to root and stem biomass partitioning in the interior Douglas-fir population of British Columbia. [ABSTRACT FROM AUTHOR]

This article focuses on water security in Mykolaiv, a city of 0.5 million inhabitants in southern Ukraine, in the situation of scarcity of usable water resources caused by climate change and military operations. This problem arose after the Dnipro-Mykolaiv water pipeline was destroyed in April 2022 as a result of military operations and the supply of drinking water to the city was cut off. To ensure that the city's population has constant access to sufficient water of acceptable quality, a search for alternative water sources and a climate risk assessment were carried out for the new municipal water supply system from the Southern Bug River. The possible change in flow and its intra-annual distribution under the influence of climate change was modeled using the WaterGAP2 hydrological model and climate projections under the SSP1-2.6 and SSP5-P8.5 scenarios. It was found that under the SSP1-2.6 scenario, the reduction in river flow will be insignificant (up to a maximum of 14% in the far future) and there will be no restrictions on the city's water supply from this section of the river in the near (2021-2050) and far (2051-2080) period. The maximum water withdrawal for municipal water supply and the minimum environmental flow will reach their maximum value only in August (56% of the projected flow), which is not critical. Under the SSP5-8.5 scenario, in the long-term perspective of 2051-2080, the largest decrease in runoff will occur from May to October, and the water withdrawal will increase to 40-79% of the projected flow. The use of the research results not only in water management, but also in municipal administration, and their dissemination in territorial communities will contribute to the successful adaptation of socioeconomic and environmental processes in the region and can bring successful benefits not only to the economy, but also to communities. [ABSTRACT FROM AUTHOR]

Water resource planners and managers in the Mid‐Atlantic United States typically determine the sufficiency of water supplies to meet demand by comparing (1) water use as reported to the state by individual water users to (2) metrics of water availability calculated from observed water monitoring networks. This paper focuses on determining whether this means of measuring water use is sufficient for proactive and sustainable management of water resources. The Potomac basin study area illustrates the point that, while state‐reported water use databases typically cover the largest individual water users, unreported water uses can cumulatively comprise a substantial portion of the overall water use. If left unaccounted for, the system is vulnerable to human demand exceeding supplies, with attendant detrimental effects to aquatic habitats and organisms, especially given the exacerbating effects of climate change on the variability of water supplies. Planners and managers are therefore encouraged to consider the full spectrum of water uses, regardless of state reporting requirements. [ABSTRACT FROM AUTHOR]

Organisms have adapted to dynamic river flows as part of the natural flow regime. However, climate change and humans' use of fresh water are associated with decreases in the quality and quantity of surface waters. In addition, river impoundments and water withdrawals for human use regulate and dampen the dynamism of flow in many rivers. These changes to the natural flow regime can impact the spawning migrations of lampreys (Petromyzontiformes). Here, our goal is to review the ecology of lamprey spawning migrations associated with river flows, with considerations for controlling invasive sea lamprey (Petromyzon marinus) and conserving native lampreys (including native, anadromous sea lamprey). We identify five common themes: (1) natural flow regimes provide a competitive edge to native fishes over non‐native fishes; (2) high flows (up to a threshold) attract adult lamprey and large streams attract large numbers of lamprey; (3) larval lamprey pheromones attract adult lampreys; (4) behavioral responses by adult lamprey to flow (including localized hydraulics) can inform dam passage and trapping methods; and (5) changes to rivers induced by climate change have been implicated in changing the phenology of run timing and spawning location. Controlling invasive sea lamprey and conserving native lampreys can be done with pheromones and flow management. Pheromones may be of more use under focused management efforts to control invasive sea lamprey, whereas flow management can provide a foundation for conservation of native lampreys. [ABSTRACT FROM AUTHOR]

The study shows variations in the volumes of water consumption and disposal, as well as the mass of pollutant discharges in the Russian part of the Ural River basin under changing socioeconomic and technological conditions and gives estimates of water quality transformations in the river. It was found that since 1990 to 2022, water withdrawal for meeting the needs of the population and economy in the Russian part of the Ural River basin decreased by 3.9 times. The water turnover factor in the basin increased from 70.3 to 91.6%. The mass of most pollutants in the discharged wastewater has decreased by 3–20 times, though five pollutants show an appreciable increase in their discharge volumes. In the upper reaches of the Ural River, the water quality estimated by the specific value of combinatory water pollution index has practically not changed in 2008–2020, while in its middle reaches, an increase in water quality was recorded. [ABSTRACT FROM AUTHOR]

Following the Environmental Kuznets Curve hypothesis, an inverted U-shaped relationship is expected between economic growth and water utilization and pollution. As economic growth increases, so do water use and pollution. However, above a certain growth level (turning point), further growth has beneficial impacts, using less water and improving its quality. Recently, N-shaped relationships seem to prevail over inverted U curves — there is a rebound effect. However, the empirical evidence shows conflicting results, partly explained by the mobility and aggregation of economic activities across a large space (the whole country). Accordingly, we build a unique dataset with measures of water use (the ratio of water withdrawals to renewable water resources) and pollution (biological oxygen demand) to estimate water utilization and pollution equations using panel data from the 32 Mexican states (2005–2020). The article's contributions are threefold. First, it introduces methodological innovations to address endogeneity using advanced panel data econometric techniques. Second, it provides new insights into the economic growth-water relationship, identifying N-shaped patterns for water use and inverted N-shaped patterns for water pollution. Third, it discusses policy implications and future research directions in environmental management and sustainable development. The findings suggest improvements for inter-regional water trade and indicate that economic growth may lead to sustainable water pollution patterns, highlighting the potential for regulatory interventions to mitigate pollution and promote efficient water use. [ABSTRACT FROM AUTHOR]

Water withdrawals are expected to continue growing, further straining available freshwater resources for economies. This review focuses on two key relationships between water and economic growth for developed and developing countries. Rising freshwater withdrawals and stress are directly related to how our economies use water to develop and grow. There is also concern that increasing water scarcity will impact economic growth across countries and regions. Unless there is a marked improvement in the water intensity of countries, economic growth will be the most important driver of increasing water withdrawals and scarcity. Although analysis of the impact of freshwater stress on the growth of economies is inconclusive, there is mounting evidence of an impact at the river basin and sub-national level. Decoupling rising water use from growth will require major water management reforms. Two of them are discussed here: Ending excessive subsidization of irrigation and reallocating subsidies for water supply and sanitation to expand delivery in developing countries. [ABSTRACT FROM AUTHOR]

Synergetic energy-water-carbon pathways are key issues to be tackled under carbon-neutral target and high-quality development worldwide, especially in ecologically vulnerable regions (EVRs). In this study, to explore the synergistic pathways in an EVR, a water-energy-carbon assessment (WECA) model was built, and the synergistic effects of water-energy-carbon were comprehensively and quantitatively analyzed under various scenarios of regional transition. Shaanxi Province was chosen as the representative EVR, and Lower challenge (LEC) and Greater challenge (GER) scenarios of zero-carbon transition were set considering the technological maturity and regional energy characteristics. The results showed that there were limited effects under the zero-carbon transition of the entire region on reducing water withdrawals and improving the water quality. In the LEC scenario, the energy demand and CO2 emissions of Shaanxi in 2060 will decrease by 70.9% and 99.4%, respectively, whereas the water withdrawal and freshwater aquatic ecotoxicity potential (FAETP) will only decrease by 8.9% and 1.6%, respectively. This could be attributed to the stronger demand for electricity in the energy demand sector caused by industrial transition measures. The GER scenario showed significant growth in water withdrawals (16.0%) and FAETP (36.0%) because of additional biomass demand. To promote the synergetic development of regional transition, EVRs should urgently promote zero-carbon technologies (especially solar and wind power technologies) between 2020 and 2060 and dry cooling technology for power generation before 2030. In particular, a cautious attitude toward the biomass energy with carbon capture and storage technology in EVRs is strongly recommended. [ABSTRACT FROM AUTHOR]

Ensuring the protection of the aquatic environment and addressing the water scarcity and degradation of water quality in the Mediterranean region pose significant challenges. This study specifically aims to assess the impact of urban and industrial pollution on the ZAT River water quality. The study exploits a combination of field measurements and mathematical simulations using the PEGASE model. The objective is to evaluate how water quality changes throughout the different seasons and to determine whether olive oil factories discharge industrial wastewater into the river. The study reveals that the river water quality remains relatively stable along its course, up to km 64 in winter and km 71.77 in summer, where poor water quality is recorded. This degradation can be attributed to multiple factors. One of these factors is the discharge of industrial wastewater, which accounts for 47% of the COD pollution load. This industrial wastewater is released into the river without treatment during the production period (January–February) and inactivity period (March–May). The combined impact of urban and industrial wastewater is also associated with the decrease in water flow resulting from water withdrawals due to irrigation canals and groundwater recharge, which both contribute to the observed changes in river water quality. Importantly, field measurements combined with results obtained from the calibrated model provide compelling evidence of unauthorized wastewater discharges from the olive oil factories into the river. These results emphasize the need for stricter regulation, such as developing water quality monitoring strategies based on the use of modeling methodologies. They also emphasize the importance of improving wastewater management practices, such as setting up treatment plants for different sources of pollution or developing a co-treatment plant to mitigate the adverse impact of industrial pollution on river water quality. [ABSTRACT FROM AUTHOR]

Central Asia (CA) is a young integrated region formed after the collapse of the Soviet Union, with most of its infrastructure based on fossil fuels. The traditional energy and water infrastructure is facing huge inefficiency and technical losses. This study investigates the transition of the green, blue, and energy economies in Central Asia using a small-dimensional panel dataset on five countries, Uzbekistan, Kazakhstan, Kyrgyzstan, Tajikistan, and Turkmenistan, over the period 1995–2018. The authors analyze the impact of ecological footprint, water withdrawal, and energy consumption on gross domestic product. In applying the Panel Vector Error Correction Model, evidence was found supporting the long-running association between variables. Furthermore, the adjustment coefficients suggest that only GDP growth will adjust toward equilibrium. Overall, the findings suggest a more effective role of green transition compared to blue and energy transitions. [ABSTRACT FROM AUTHOR]

Carbon capture, utilization, and storage (CCUS) technologies are an integral part of the carbon-neutral technology portfolio at the present phase. However, large-scale implementation of CCUS technologies may increase urban water consumption and raise urban water security issues. In this paper, 596 large-scale coal-fired power plants were investigated in terms of water withdrawal and water consumption. To minimize total water withdrawal and total water consumption, a source-sink matching model for CCUS projects under water resource constraints was established to optimize the layout of CCUS projects in China. The results show that there is a mismatch between the distribution of coal-fired power plants in a spatial location and water resources. The annual increase in water withdrawal of about 27.6 billion tons and water consumption of about 2.4 billion tons is needed to achieve the 2 °C target, which will aggravate the water scarcity in the north-central cities. Implementation of CO2-enhanced water recovery (CO2-EWR) technology can offset some of the increase in urban water consumption owing to CCUS deployment. This study can provide data support for site selection in the large-scale deployment of CCUS technology and provide the theoretical basis for decision-makers to lay out CCUS projects. [ABSTRACT FROM AUTHOR]

Reflecting on the 2023 assertion by the Global Commission on the Economics of Water that the depletion of blue water by irrigation contributes to the global water crisis, we critique two previous contributions by one of its authors, Johan Rockström. First, to bridge agro-meteorological drought, rainfed (green water) farmers should irrigate. If not regulated, this increases water withdrawals and depletion. Second, the continuum of agricultural water management is a field-scale emphasis on rainfall and/or irrigating to top up soil moisture. This emphasis hinders taking a multi-scale irrigation systems approach to resolve blue water depletion and its inequitable impacts. [ABSTRACT FROM AUTHOR]

Maize is vital in Ethiopia, particularly in Jimma. However, the benefits of deficit irrigation (DI) under varying nitrogen rates (NRs) for maize remain unknown. A 3-year field experiment assessed maize response to different NRs (N0=0 kg ha−1 , N23=23 kg ha−1 , N46=46 kg ha−1 , N69=69 kg ha−1 , and N92=92 N kg ha−1) under three DI levels (I50=50 , I75=75 , and I100=100% ETc). Factors such as rain-fed findings, soil testing, and local recommendations were considered in determining these rates. The results showed significant effects of DI, NR, and their interactions on grain yield, biomass, water-use efficiency (WUE), nitrogen-use efficiency (NUE), and harvest index (HI). Without nitrogen, 50% DI led to a greater than 50% reduction in yield and biomass compared with that at I100×N0. However, WUE and HI increased at I50×N92 compared with I100×N0. Increasing irrigation and nitrogen levels improved yield and biomass. Optimal WUE was achieved with irrigation close to 75% ETc without compromising yields. Agronomic yield significantly improved with NR above 92 kg N ha−1 under mild deficit and full irrigation, but higher rates did not provide additional benefits under severe deficit conditions. The economically optimum nitrogen rate ranged from 78 to 80 kg N ha−1 for irrigation levels ranging from 50% to 100% ETc. The study suggests that applying 80 kg N ha−1 with 75%–100% ETc levels is the best approach to enhance maize yield and achieve economic benefits. Further research is needed to explore DIs below 50% and above 100% ETc, as well as nitrogen fertilization rates above 92 kg ha−1 , in order to optimize maize production in the region. Practical Applications: This study examined the benefits of deficit irrigation and fluctuating nitrogen rates for maize production in Jimma, Ethiopia. By adopting deficit irrigation strategies and adjusting nitrogen rates, producers can reduce water withdrawal by approximately 25%. This approach optimizes both water-use efficiency and nitrogen-use efficiency without compromising yields. Increasing irrigation and nitrogen rates above I100×N92 improves agronomic yield, whereas reducing them below I50×N46 significantly decreases yield and WUE. Economically optimum nitrogen rates range from 78 to 80 kg N ha−1 with 50%–100% full irrigation. Balancing input costs and potential benefits is crucial for optimizing irrigation and nitrogen rates for maize production. To maximize agronomic yield, full irrigation with 92 kg N ha−1 (less than 96 kg N ha−1) is advisable. To optimize water use, 75% of full irrigation with 92 kg N ha−1 is recommended. To optimize nitrogen (economic yield) and achieve higher net returns, fully irrigating the maize crop with 80 kg ha−1 of nitrogen fertilization is advised. Farmers should adapt these findings to local conditions, considering factors such as soil characteristics, nitrogen price, and water price, and should consult local experts. Further research is needed to explore the effects of more or less than 50% full irrigation and of nitrogen doses exceeding 92 kg ha−1. [ABSTRACT FROM AUTHOR]

Lake Urmia in the northwest of Iran is one of the largest vanishing lakes in the world. Several water-saving strategies have been implemented in the lake basin over the last decade, but they are not producing efficient results. This study employed a modified version of the Soil and Water Assessment Tool (SWAT), an agrohydrological model, to investigate the basin-scale effectiveness of some water-saving plans implemented at the farm scale. Data collected from 301 monitoring sites in the Lake Urmia basin were applied to the modified SWAT model. The modified SWAT model was used to estimate water balance components and was coupled with the Water Accounting Plus framework (WA+). Six discharge stations, crop yields, evapotranspiration, and groundwater level tables were calibrated and validated from 1987 to 2015 within the Zarrineh Rud Basin (ZRB), the most crucial subbasin in the Lake Urmia basin. Next, four individual water-saving plans—changes in irrigation management and developments in irrigation systems, changes in fertilizer type and regime, changes in the type and method of cultivation, and farm size and shape adjustments—as well as seven combinations of the water-saving plans, were applied to the agrohydrological model. The results reveal that assessing restoration plans for Lake Urmia without considering both farm and basin scales provides no reliable results. With changes in management and the development of irrigation systems, considerable differences in water withdrawal were observed. Developing irrigation systems leads to enhanced water consumption and evapotranspiration, which is expected to improve water yield and crop productivity. However, individual plans such as developments in irrigation systems cannot increase the inflow to Urmia Lake, and combined water-saving strategies can help restore the lake only to a limited extent, because the changes in inflow are not substantial. [ABSTRACT FROM AUTHOR]

Global forest plantations are expanding, causing land-use changes and impacting the water cycle. This study assesses whether eucalyptus plantations reduce groundwater levels compared to grasslands in paired subtropical watersheds. The hydrological dynamics of surface and subsurface water were compared in three small watersheds in southern Brazil, mainly occupied by Eucalyptus saligna (Es-W, 79.9 ha), Eucalyptus benthamii (Eb-W, 82.1 ha), and degraded anthropized natural grassland (G-W, 109.4 ha). Rainfall, flow, and piezometric levels were monitored. Runoff, evapotranspiration, and water balance in the soil profile were estimated, and the subsurface environment was characterized using electrical resistivity tomography. During higher accumulated rainfall, water surplus increased for all watersheds. In the wet period (accumulated rainfall of 1098.0 mm), evapotranspiration was higher for eucalyptus (624.3 mm for Eb-W and 512.5 mm for Es-W) than for the grassland watershed (299.5 mm), resulting in the highest runoff in G-W (649.6 mm). During the dry period (accumulated rainfall of 478.5 mm), water deficit and withdrawal were mainly observed in forested watersheds, decreasing groundwater. Combining water balance and electrical resistivity tomography estimations results in a better understanding of the hydrological dynamics in paired watersheds with different land uses. This information is useful for developing best-practice management strategies for sustainable water resource use and forest production. [ABSTRACT FROM AUTHOR]

The knowledge of factors that influence the waters present in the hydrographic basins is extremely important for efficient management, considering its multiple uses. In this regard, the present work aims to apply mathematical modeling tools, expressed by the HRI-Hydro Tools, the hydrological model of large basins and WARM-GIS Tools, to carry out the physical characterization, hydrological modeling, and the quantitative water balance, for the Jaguarão River hydrographic basin (JRhb). In two scenarios, monthly-based, the reference flow adopted was Q90. Further the water stress index (WSI) was applied for each section of the JRhb drainage network, with emphasis on the analysis of the influence of multiple uses of water in the basin, especially for irrigation. The water withdrawal index (WWI) was used to develop a diagnosis of the watershed level of scarcity, taking into account the annual water commitment, to improve the quantitative representation of water for the JRhb. The results of the hydrological modeling performed showed that, in general, the model presented a good performance both in the calibration and in the validation of the studied periods. The WSI representation showed that in the current scenario (realistic scenario) the basin has been suffering great water stress in the months that comprise the summer season (December, January, February, and March). In addition, the application of the WSI exposed the great influence of water use in the production of irrigated rice in this territory. This result was supported by WWI, which revealed sub-basins that were in a vulnerable state, requiring intensive management and major mitigation efforts. [ABSTRACT FROM AUTHOR]

Objective To explore the clinical effect of umbilical moxibustion on chronic heart failure with yang deficiency and blood stasis and water retention syndrome. Methods 80 patients with chronic heart failure who were hospitalized in the Department of Cardiology, Shenzhen Hospital (Longgang), Beijing University of Chinese Medicine from January 1, 2021 to December 31, 2022 were selected as research samples and randomly divided into control group (40 cases, 40 cases completed) and observation group (40 cases, 40 cases completed) . The control group received standard drug treatment, while the observation group received umbilical moxibustion treatment on the basis of drug treatment. Ten days after treatment, NT-proBNP, NYHA cardiac function classification, cardiac color Doppler indexes (including LVEF, LVEDD, LVSD), Minnesota quality of life score, 6-minute walking distance and TCM syndrome score were compared between the two groups before and after treatment, and the occurrence of adverse reactions was monitored and recorded. Results The total effective rate in the observation group was higher than that in the control group (χ2 = 3.865, P = 0.049) . NYHA cardiac function classification, NT-proBNP, LVEF, LVEDD, LVESD and 6-minute walking distance in both groups were significantly improved compared with those before treatment, and the improvement of the above indexes in the observation group was more significant (P < 0.05) . The Minnesota quality of life score and TCM syndrome score of the two groups decreased compared with those before treatment, and the decline of the patients in the observation group exceeded that of the control group (P < 0.05) . During the treatment, the two groups had adverse reactions (such as gastrointestinal reaction, hypotension, skin allergy, etc.), and there was no difference between the two groups (P > 0.05). Conclusion On the basis of drug therapy, umbilical moxibustion is better than simple drug therapy in treating chronic heart failure with yang deficiency, blood stasis and water stagnation, which can improve the cardiac function and quality of life of patients with chronic heart failure. [ABSTRACT FROM AUTHOR]

Groundwater numerical modeling is a crucial scientific tool for understanding groundwater circulation and supporting regional water resource planning and management. The effectiveness of these models depends largely on the accuracy of hydrogeological parameters within aquifers, which are often spatially heterogeneous and randomly distributed due to complex geological and tectonic factors. Traditional modeling approaches frequently overlook this randomness, compromising the precision and resolution of groundwater simulations. This study focuses on a section of the Qingshui River in the Huaihe River Basin. Using field and laboratory data, probability distribution functions for key parameters like hydraulic conductivity, specific yield, and specific storage were developed. These functions were integrated into the groundwater model to reflect the inherent stochastic nature of aquifer properties. This integration significantly enhanced model accuracy, reducing the root mean square error of simulated water levels from 0.47-1.43 m to 0.13-0.16 m and improving the Nash-Sutcliffe efficiency coefficients (NSE) from -2.96-0.73 to 0.94-0.98. Additionally, the model facilitated analysis of the interactions between river and groundwater, particularly in the hyporheic zone, under various scenarios. It identified spatial and temporal variations in groundwater recharge dynamics and delay effects at different distances from the river channel. For instance, recharge rates at 50 m and 150 m from the river were 0.295 m/day and 0.015 m/day, respectively, indicating stronger recharge closer to the river. The study also assessed the impact of varying river flows, riverbed permeability, and irrigation practices on water exchanges between the river and groundwater. These factors were found to significantly influence the intensity of water exchange, seepage, and groundwater reserves. This research provides valuable insights for managing river-groundwater interactions and analyzing the ecological environment of surrounding groundwater systems, underscoring the importance of incorporating stochastic characteristics into groundwater modeling. [ABSTRACT FROM AUTHOR]

Efforts to predict long‐term changes in continental runoff at both global and basin scales generally remain ambiguous. Here we use a global runoff reconstruction and a Bayesian statistical method to narrow uncertainties in runoff projections from the latest generation of global climate models. Three representative tropical river basins are used to illustrate the application and showcase the potential for substantial reduction in modeling uncertainty. Yet, results are fairly sensitive to the selected reconstruction thus highlighting the need for reliable and homogeneized gridded runoff data sets or river discharge measurements. Moreover, climate models do not account for water withdrawals, whose effect on observed runoff should also be removed in order to detect and attribute the hydrological effect of climate change. Finally, and more importantly, most models fail at capturing the observed recent decrease in runoff ratio, which may highlight either model deficiencies or increasing water derivation over the selected river basins. Plain Language Summary: The response of river discharge under the effect of climate change generally remains very uncertain. Bayesian statistical tools and global runoff reconstructions, constrained by flow observations, can nevertheless be used to evaluate the capacity of climate models to simulate the historical runoff and, thus, constrain its future changes at the basin scale. Three representative tropical river basins help illustrate the method. The results are nevertheless sensitive to the choice of the runoff reconstruction, thus emphasizing the need to have good quality flow data, if possible corrected for the direct effects of water withdrawals from the rivers or the aquifers which supply them. Worryingly, the latest generation of global climate models show a systematic underestimation of the downward evolution of the ratio between runoff and precipitation, which could reflect the increasing importance of these withdrawals or the inability of models to capture the rapidly increasing land surface evapotranspiration under climate change. Key Points: Global 21st century projections of basin‐scale runoff remain highly model‐dependent within the latest generation of Earth System ModelsGridded runoff reconstructions and precipitation observations can however be used to constrain the projections through Bayesian statisticsA model‐observation mismatch is underlined regarding recent changes in the annual runoff to precipitation ratio over specific river basins [ABSTRACT FROM AUTHOR]

Agriculture water use accounts for 70% of the total water withdrawal worldwide. The evapotranspiration during crop growth is one of the important hydrological processes in the agricultural water cycle. This study proposed the concept of artificial irrigation evapotranspiration of irrigated crops to describe that the evapotranspiration caused by irrigation water use. Irrigated crops rely on two kinds of water sources: precipitation and irrigation water. With the construction of irrigation schemes, the artificial irrigation evapotranspiration plays an increasingly important role in the dualistic water cycle system of irrigated cropland. To reveal the amount of artificial irrigation evapotranspiration of 17 categories of irrigated crops in China, this study proposed a new quantitative model system which was established based on traditional evapotranspiration models and soil water balance models. Based on the new model system, we calculated the annual artificial irrigation evapotranspiration of irrigated crops for the period 2013 to 2017 in China. The results showed that the proportion of artificial irrigation evapotranspiration to the total evapotranspiration of irrigated crops was 41.3%, whose value was 228.1 km3 a−1. The artificial irrigation evapotranspiration in different agricultural water management regions were 90.0 km3 a−1 in the northeast region, 86.0 km3 a−1 in the southeast region, and relatively low 52.2 km3a−1 in the west region. The results of this study can provide methods for water management and policy–making in agricultural irrigated areas, and it can also provide a preliminary understanding of the influence of human activities on the dualistic water cycle in cropland. [ABSTRACT FROM AUTHOR]

Drought is a major factor affecting crops, thus efforts are needed to increase plant resilience to this abiotic stress. The overlapping signaling pathways between drought and cell wall integrity maintenance responses create a possibility of increasing drought resistance by modifying cell walls. Here, using herbaceous and woody plant model species, Arabidopsis and hybrid aspen, respectively, we investigated how the integrity of xylan in secondary walls affects the responses of plants to drought stress. Plants, in which secondary wall xylan integrity was reduced by expressing fungal GH10 and GH11 xylanases or by affecting genes involved in xylan backbone biosynthesis, were subjected to controlled drought while their physiological responses were continuously monitored by RGB, fluorescence, and/or hyperspectral cameras. For Arabidopsis, this was supplemented with survival test after complete water withdrawal and analyses of stomatal function and stem conductivity. All Arabidopsis xylan-impaired lines showed better survival upon complete watering withdrawal, increased stomatal density and delayed growth inhibition by moderate drought, indicating increased resilience to moderate drought associated with modified xylan integrity. Subtle differences were recorded between xylan biosynthesis mutants (irx9, irx10 and irx14) and xylanaseexpressing lines. irx14 was the most drought resistant genotype, and the only genotype with increased lignin content and unaltered xylem conductivity despite its irx phenotype. Rosette growth was more affected by drought in GH11- than in GH10-expressing plants. In aspen, mild downregulation of GT43B and C genes did not affect drought responses and the transgenic plants grew better than the wild-type in drought and well-watered conditions. Both GH10 and GH11 xylanases strongly inhibited stem elongation and root growth in well-watered conditions but growth was less inhibited by drought in GH11-expressing plants than in wild-type. Overall, plants with xylan integrity impairment in secondary walls were less affected than wild-type by moderately reduced water availability but their responses also varied among genotypes and species. Thus, modifying the secondary cell wall integrity can be considered as a potential strategy for developing crops better suited to withstand water scarcity, but more research is needed to address the underlying molecular causes of this variability. [ABSTRACT FROM AUTHOR]

In this study, the agro-hydrological model Soil and Water Assessment Tool + (SWAT+) is used to simulate runoff in an uncontrolled agricultural catchment with paddy fields irrigated by plots submersion. The objectives are to evaluate the ability of this new, improved version of the SWAT model to reproduce the flows in a complex catchment and to analyse the evolution of these flows over the historical period 1986-2020 (35 years). Sensitivity analysis, calibration and validation were carried out with monthly flow data. The decision tables for irrigation operations and reservoir water release were filled in the SWAT+ Editor to establish the reservoir water balance. The Mann-Kendall trend test with the threshold of the standard normal statistic = 1.96, was applied to the time series of flows to the Nanan Reservoir. The results reveal that SWAT+ is more sensitive to eight parameters, including the new CN3_SWF parameter (-0.04329), which gave the user control of the soil saturation level. Good performances were obtained during calibration and validation, respectively: NSE (0.78; 0.69); R² (0.81; 0.70); PBIAS (-18.58; -23.9) and RSR (0.47; 0.56), with a tendency to slightly overestimate flows. The analysis shows that flows to the Nanan Reservoir are highly variable yearly, with a non-significant upward trend (|Z|=1.3<1.96) from 1986 to 2020. The water balance reveals that the runoff inflow generated will compensate for water withdrawals for irrigation of the Nanan paddy scheme during this period. Furthermore, this study provides a methodological framework for SWAT+ reservoir model calibration in an uncontrolled catchment. [ABSTRACT FROM AUTHOR]

This paper examines the prospects for developing and implementing a binational water management agreement for the transboundary Santa Cruz River that crosses the US–Mexico boundary near the sister cities of Nogales, Sonora–Nogales, Arizona. After considering the geography, history, socio-economic context, and binational agreements affecting utilization of the Santa Cruz River, we review the conditions influencing recent binational progress on another transboundary river, the Tijuana River. Specifically, we ask what conditions created a favorable environment in which a binational agreement for management of the Tijuana River Watershed (TRW) was developed, what specific actions by relevant policy officials took place, and how the final agreement was reached. We then compare the dynamics that unfolded in the TRW with conditions in the Santa Cruz River to identify obstacles hindering progress towards achieving an International Boundary and Water Commission (IBWC) agreement (Minute) on shared management of the Santa Cruz River in its international reach. We find that the required political conditions that favored an agreement on the Tijuana River are not yet met on the Santa Cruz, although several favorable conditions do exist. We conclude with an assessment of current prospects for advancing binational cooperation that can inform discussion of how an IBWC Minute could be drafted to address water resource management issues in the Santa Cruz River Basin. [ABSTRACT FROM AUTHOR]

Estimation of human water withdrawals is more important now than ever due to uncertain water supplies, population growth, and climate change. Fourteen percent of the total water withdrawal in the United States is used for public supply, typically including deliveries to domestic, commercial, and occasionally including industrial, irrigation, and thermoelectric water withdrawal. Stewards of water resources in the USA require estimates of water withdrawals to manage and plan for future demands and sustainable water supplies. This study compiled the most comprehensive conterminous United States water withdrawal data set to date and developed a machine learning framework for estimating public supply withdrawals and associated uncertainty for the period 2000–2020. The modeling approach provides service area resolution estimates to allow for annual and monthly water withdrawal estimation while incorporating a complex array of driving factors that include hydroclimatic, demographic, socioeconomic, geographic, and land use factors. Model results reveal highly variable and lognormally distributed per‐capita water withdrawal, spanning from 30 to 650 gallons per capita per day (GPCD), across community, regional, and national scales, with pronounced seasonal variations. Analysis of estimated withdrawal trends indicates that the national annual average withdrawal experienced a decline at a rate of 0.58 GPCD/year during the period from 2000 to 2020. Model interpretation reveals a complex interplay between public supply withdrawal and key predictors, including population size, warm‐season precipitation, counts of large buildings and houses, and areas of urban and commercial land use. The developed models can forecast future public supply driven by various climate, demographic, and socioeconomic scenarios. Key Points: Consistent, reproducible estimates of monthly water withdrawals were generated at the spatial resolution of USA water service areasSpatial and temporal variability of public supply withdrawal is driven by a complex array of explanatory featuresAn operational machine learning framework was developed to estimate water withdrawals, prediction uncertainty, and feature importance [ABSTRACT FROM AUTHOR]

Swimming venues provide various services based on water as the carrier, but studies on their water use are few. This study constructed a stochastic model to quantify the water use efficiency of indoor swimming venues under different scenarios based on Monte Carlo simulation. It explored the impact of shower behavior, swimming pool replenishment rate, and appliance water efficiency on water use efficiency in swimming venues. The results show that the indoor swimming pool replenishment volume and shower water use accounted for relatively high proportions and are relatively stable, with a total of about 81 % of the total water use; the model could effectively quantify the water demand in swimming pools under different scenarios. The theoretical water withdrawal of the swimming pool per unit volume under the saving mode and the reasonable mode are 26.32 m3 /(m3 ·a) and 34.71 m3 /(m3 ·a) respectively, which are comparable to the water use quota values of swimming venues by region in China. Conclusions could be drawn from sensitivity analysis that replenishment rate is the most important factor affecting the water withdrawal per unit volume of the swimming pool, followed by shower duration. This study provides theoretical basis for water-saving management to swimming venue managers, and reference for different industries to carry out research on the mechanism of water use behavior and water demand analysis. [ABSTRACT FROM AUTHOR]

This work studies the multiple sources of impacts and disturbances in the Laja River (Central Chile) and evaluates the changes in water and sediment flows and planimetric geomorphic changes. The disturbances sources correspond to hydroelectric plants, water withdrawals for irrigation and the sustained decrease trend in rainfall in the basin. The changes in the plan‐view shape of the river reach were quantified using remote sensing techniques, through a supervised classification of Landsat 5 TM and 8 OLI satellite images, identified Water (W), Islands and Riverine Vegetation (IRV) and Bars and Banks Without Vegetation (BBWV), obtained a Kappa index>0,83 for a period of 15 years (2006–2021). Compared with historical records, the period of analysis shows a decrease in annual rainfall by 17.5%. In addition, water withdrawals for irrigation have contributed to a 64% decrease in monthly stream discharge during the dry season. As a consequence of the decrease in annual rainfall and water withdrawals for irrigation, the sediment transport capacity has also decreased by 10.5%. The changes in morphological driving variables (stream flows and sediment transport regimes) have manifested themselves in morphological changes, where it was possible to establish that a change in the channel form occurred in the last 15 years, going from a river with a single channel to a braided one. An important vegetation establishment has accompanied this morphological change on both riverbanks and the central bars. The colonizing vegetation corresponds to fast‐growing non‐native species (Salix spp., Populus spp. and Alnus spp). A stabilization of the channel form is expected, consolidating itself as a braided section with alternating vegetated bars. [ABSTRACT FROM AUTHOR]

There is a growing concern about limited water supply and water scarcity in many river basins across the world. The agricultural sector is the largest user of freshwater on the planet, with a growing amount of water extracted for livestock systems. Here, we use data from the GLEAM model to advance previous studies that estimated livestock water footprints by quantifying water use for feed production, animal drinking water, and animal service water. We additionally account for the role of trade in accounting for feed water allocations to different animals in different countries and make use of a hydrologic model to estimate feed irrigation water requirements for individual crops at a high spatial resolution. Lastly, we estimate the contribution of livestock water abstractions to water stress at a small river basin scale for the entire globe. We find that feed production water accounts for the majority (>90%) of global livestock water withdrawals, though there is regional variation. Similarly, we find large regional variation in the water consumption per head by livestock species. Despite consuming >200 km3 of water per year, we find that reducing water use in the livestock system alone will rarely reduce water stress in high-stress basins. This study highlights the need for quantifying locally relevant water use and water stress metrics for individual livestock systems. [ABSTRACT FROM AUTHOR]

Many states in the Eastern U.S. have limited water withdrawal regulations, posing significant risks to water supply management during periods of low flows. While these states require water withdrawal permits, exemptions for grandfathered withdrawals that allow unregulated access to surface water are common. Such permit exemptions present a challenge to water supply management, as full utilization of allowable withdrawals by permit‐exempt users could pose risks to maintaining adequate water supplies for current and projected demand. This study used reported permit exemption data in Virginia to understand the extent, volume, and potential impact of permit‐exempt withdrawals on 30‐ and 90‐day low flows. The permit‐exempt withdrawal values used in this study were obtained from Virginia Department of Environmental Quality. Maximum permit‐exempt withdrawal volumes were significantly higher than projected future demands in permitted users. The impacts of these withdrawals on drought flows were compared with the impacts presented by climate change and demand growth. Widespread reduction in flows was observed with the "dry" future climate change scenario, while impacts were more localized in the exempt users and the demand growth scenarios. The impacts of exempt users exceeded the impact of climate change and demand growth scenarios in many regions during low‐flow periods. Therefore, more comprehensive water planning, policy and research is needed to address the impact of permit exemptions. [ABSTRACT FROM AUTHOR]

Interbasin water transfer projects (IBWTPs) have become an important measure to alleviate regional water stresses by artificially regulating water resources between water-rich and water-scarce areas. However, there are many conflicting objectives and complex practical operational constraints that complicate the derivation of water allocation schemes for IBWTPs. Here, we propose a multiobjective optimization methodology for deriving water allocation schemes for IBWTPs, which includes three modules: (1) formulating a multiobjective optimal water allocation problem for IBWTPs based on practical operational constraints; (2) proposing a novel multiobjective cuckoo search (NMOCS) algorithm and combining it with a simulation-optimization approach to solve the water allocation problem; and (3) filtering the Pareto solutions using the analytic hierarchy process (AHP)-entropy method. Based on the multiobjective cuckoo search (MOCS) algorithm, the NMOCS employs four improvement strategies, including a population initialization strategy, flock search strategy, multistrategy external archive maintenance strategy, and adaptive parameters, to improve the convergence property and diversity of solutions. To test the performance of the NMOCS, we considered the MOCS and four widely used multiobjective evolutionary algorithms (MOEAs) as a comparison and employed these six MOEAs to solve 11 multiobjective mathematical benchmark problems as well as the water allocation problems of the Jiangsu Province, China, section of the South-to-North Water Diversion Project under normal, dry, and extremely dry hydrological conditions. The results show that the NMOCS outperformed other MOEAs in handling multiobjective mathematical benchmark problems, especially in ZDT1, ZDT2, ZDT6, DTLZ2, DTLZ4, and DTLZ7. Compared with other MOEAs, the NMOCS did not always capture the highest percentage of the reference water allocation schemes, but it provided more than 18% (greater than one-sixth) of effective water allocation schemes for all hydrologic conditions. Meanwhile, compared with optimal water allocation schemes derived from other MOEAs, the NMOCS effectively improved the operational performance under normal and drought hydrological conditions, especially in the total water pumping and the water withdrawn from the Yangtze River. This research can help to update our understanding of MOEAs, particularly the MOCS, and serve as a reference for better-allocating water resources in IBWTPs. [ABSTRACT FROM AUTHOR]

The increasing temperature in the Yellow River Basin has led to a rapid rise in the melting level height, at a rate of 5.98 m yr-1 during the cold season, which further contributes to the transition from snowfall to rainfall patterns. Between 1979 and 2020, there has been a decrease in snowfall in the Yellow River Basin at a rate of -3.03 mm dec-1, while rainfall has been increasing at a rate of 1.00 mm dec-1. Consequently, the snowfall-to-rainfall ratio (SRR) has decreased. Snowfall directly replenishes terrestrial water storage (TWS) in solid form until it melts, while rainfall is rapidly lost through runoff and evaporation, in addition to infiltrating underground or remaining on the surface. Therefore, the decreasing SRR accelerates the depletion of water resources. According to the surface water balance equation, the reduction in precipitation and runoff, along with an increase in evaporation, results in a decrease in TWS during the cold season within the Yellow River Basin. In addition to climate change, human activities, considering the region's dense population and extensive agricultural land, also accelerate the decline of TWS. Notably, irrigation accounts for the largest proportion of water withdrawals in the Yellow River Basin (71.8%) and primarily occurs during the warm season (especially from June to August). The impact of human activities and climate change on the water cycle requires further in-depth research. [ABSTRACT FROM AUTHOR]

The flow in the draft tube of the water turbine is affected by the upstream flow and the inherent structure accompanied by various undesirable characteristics, affecting the efficient and stable operation of the water turbine. Changing the flow structure downstream of the runner is an important measure to reduce hydraulic loss in the draft tube and improve stability. In this study, three downstream structures of the runner, namely, the non-locking nut, small locking nut, and extended locking nut are numerically calculated and verified using experimental results. The unstable flow characteristics of the draft tube are analyzed using variations in swirling flow, backflow, pressure gradient, and vortex strip. The results show the non-negligible effect of the locking nut, which significantly reduces the rotational momentum flux at the draft tube inlet, accelerates the decay rate of the swirling flow, and suppresses the generation of axial low pressure. The small locking nut significantly reduces the pressure gradient, shortens the backflow zone, and decreases the backflow velocity. The extended locking nut reduces the backflow zone in some sections and reduces the vortex zone of the straight section but prolongs the backflow zone and increases the backflow velocity. [ABSTRACT FROM AUTHOR]

Ensuring the sustainable management of water and sanitation for all is the primary goal of Sustainable Development Goal 6 (SDG 6). SDG indicator 6.4.2 (level of water stress) is critical for monitoring the progress toward SDG 6. The assessment of the SDG indicator 6.4.2 is currently based on statistical data at the national scale, i.e., one value for one country, which cannot reflect spatial variability in water stress in a country. The lack of data at sub-national scales limits the assessment of water stress in sub-national regions. This study developed a method of disaggregating national statistical renewable water resources (TRWR) and freshwater withdrawals (TFWW) to estimate the SDG 6.4.2 water stress indicator at a sub-national scale by combining satellite remote sensing data and model simulated data. Remote sensing (RS)-based precipitation (P); the difference between precipitation and evapotranspiration (P-ET); and the difference between precipitation, evapotranspiration, terrestrial water storage change (P-ET-dS), and model-simulated naturized runoff and withdrawal water use were used as spatial and temporal surrogates to disaggregate the national-scale statistics of TRWR and TFWW to the grid scale. Gridded TRWR and TFWW can be used to calculate the water stress of any interest regions. Disaggregated TRWR, TFWW, and water stress estimation were validated at three different spatial scales, from major river basins and provinces to prefectures in China, by comparing the corresponding statistical data. The results show that the disaggregation for TRWR is generally better than for TFWW, and the overall accuracy for water stress estimation can reach up to 91%. The temporal evolution of disaggregated variables also showed good consistency with statistical time series data. The RS-based P-ET and P-ET-dS have great potential for disaggregating TRWR at different spatiotemporal scales, with no obvious differences with the results using the model simulation as a surrogate for the disaggregation of SDG indicator 6.4.2. The disaggregation accuracy can be further improved when the sub-regional statistical data of TRWR and TFWW are applied to the disaggregation approach. [ABSTRACT FROM AUTHOR]

Multidisciplinary information such as geophysical, hydraulic, geological, and hydrogeological information combined with GIS can be a powerful tool to better understand aquifers. The aim of this paper is to assess groundwater pollution risk through regional hydrogeological and local hydrogeophysical models built from multidisciplinary information and geophysical well logs. Once the regional model of the Toluca Valley Aquifer (Mexico) was built, the critical area (CA) of the aquifer was identified through features such as fractures and faults, pollution sources, subsidence, groundwater table depletion, and well density, which were transformed into GIS with multicriteria analysis. With the CA a local hydrogeophysical model was set to extract lithological information and compute the intrinsic vulnerability (IV) through the Dar Zarrouk parameters according to the AVI-Fr method which considers the influence of fractures and faults as preferential paths for pollutants. On the other hand, the potential harmful load (PHL) of the different pollution sources was estimated with the POSH method. Finally, with the relation between the IV and PHL, risk pollution map could be made. The results of this study show that different areas are exposed to pollution risk due to their proximity to fractures, oil and gas subsurface infrastructure and high pumping ratios and their relationships. The available geophysical data and multidisciplinary information were powerful tools for identifying the critical area of the TVA and proposing actions to mitigate or control excessive withdrawals for sustainable management. [ABSTRACT FROM AUTHOR]

The intensity of global groundwater use rose from 124 m3 per capita in 1950 to 152 m3 in 2021, for a 22.6% rise in the annual per capita use. This rise in global per capita water use reflects rising consumption patterns. The global use of groundwater, which provides between 21% and 30% of the total freshwater annual consumption, will continue to expand due to the sustained population growth projected through most of the 21st century and the important role that groundwater plays in the water‐food‐energy nexus. The rise in groundwater use, on the other hand, has inflicted adverse impacts in many aquifers, such as land subsidence, sea water intrusion, stream depletion, and deterioration of groundwater‐dependent ecosystems, groundwater‐quality degradation, and aridification. This paper projects global groundwater use between 2025 and 2050. The projected global annual groundwater withdrawal in 2050 is 1535 km3 (1 km3 = 109 m3 = 810,713 acre‐feet). The projected global groundwater depletion, that is, the excess of withdrawal over recharge, in 2050 equals 887 km3, which is about 61% larger than in 2021. This projection signals probable exacerbation of adverse groundwater‐withdrawal impacts, which are worsened by climatic trends and the environmental requirement of groundwater flow unless concerted national and international efforts achieve groundwater sustainability. [ABSTRACT FROM AUTHOR]

Fresh surface water is increasingly becoming scarcer worldwide, leading to significant groundwater over-extraction. However, groundwater over-extraction could result in many environmental externalities including various land subsidence (LS) effects. LS causes the gradual reduction of the voids and the subsequent ground surface sinking. The loss of aquifer system storage capacity, owing to LS, is one such negative externality that is seldom discussed in the economic literature. In this paper, we investigate the indirect loss of the aquifer system storage capacity due to LS along with other direct LS negative externalities. We develop a dynamic economic optimization model for groundwater utilization and evaluate various policy instruments (quota systems, taxes on land sinking and aquifer storage loss, and packaging and sequencing of taxes and quotas) to prevent overexploitation externalities. The model is calibrated to South African data. We found that taxes on land sinking and aquifer system storage capacity reduction have a significant effect on withdrawals and water table levels. Taxes provide larger social welfare. In addition, under certain circumstances, quotas are preferable when it comes to supporting groundwater conservation practices. Packaging and sequencing provide the second largest social benefits. [ABSTRACT FROM AUTHOR]

In the context of China's freshwater crisis high-resolution data are critical for sustainable water management and economic growth. Yet there is a dearth of data on water withdrawal and scarcity regardless of whether total or subsector amount, for prefectural cities. In administrative and territorial scope, we accounted for water withdrawal of all 63 economic-socio-environmental sectors for all 343 prefectural cities in China, based on a general framework and 2015 data. Spatial and economic-sector resolution is improved compared with previous studies by partitioning general sectors into industrial and agricultural sub-sectors. Construction of these datasets was based on selection of 16 driving forces. We connected a size indicator with corresponding water-withdrawal efficiency. We further accounted for total blue-water withdrawal and quantitative water scarcity status. Then we compared different scopes and methods of official accounts and statistics from various water datasets. These disaggregated and complete data could be used in input-output models for municipal design and governmental planning to help gain in-depth insights into subsector water-saving priorities from local economic activities. [ABSTRACT FROM AUTHOR]

This document discusses a research paper that focuses on intermittent water supply systems in South Asian countries, specifically in India. The authors propose a model that uses dummy components to simulate water demands in these systems. However, the discussers argue that the proposed model is not advantageous compared to an earlier model and provides different results. They suggest that replacing an artificial reservoir with a dummy emitter leads to a different depiction of water consumption behavior. The discussers analyze two models representing water consumption behavior in Integrated Water Supply systems and find a lack of data to determine which model is more accurate. They also argue that the assumption of uncontrolled water demands in these systems needs to be reconsidered and that more research is needed to understand water consumption behavior. [Extracted from the article]

Phaseolus vulgaris is one of the most widely consumed legumes across the globe. It is rich in protein, carbohydrates, fiber, bioactive compounds, and mineral contents. Occurrences of drought under changing climate have posed a challenge to the quality and quantity of the crop yield. Our study, taking Phaseolus vulgaris as a test legume, reports that as a soil amendment, biochar and farmyard manure mitigated drought-induced damage in the plant. The experiment was set up in a greenhouse with 1 m2 blocks together arranged in factorial randomized block design. Water withdrawal was done for 15 days in either vegetative or reproductive stage of the crop to simulate drought conditions. Biochar or Farmyard manure was applied at the rate of 10t ha−1 as soil amendment and each treatment was replicated thrice. Higher photosynthesis (up to 23% and 16%, respectively), leaf protein (41% and 30%, respectively), grain protein (4% and 19%, correspondingly), and in-vitro protein digestibility (60% and 254%, respectively) were noted under application of both the amendments. Grain quality in terms of protein content, in-vitro protein digestibility, and protein fractions of Phaseolus vulgaris was improved under drought due to the addition of biochar and farmyard manure. However, the application of those amendments at the rate of 10t ha−1, especially farmyard manure, had a negative impact on the antinutritional factor (phytic acid) and mineral bioavailability. Between the two amendments studied, farmyard manure proved to be more efficient in promoting the overall grain quality of P. vulgaris, but its inimical effects must be concorded. [ABSTRACT FROM AUTHOR]

We provide a dataset of irrigation water withdrawals by crop, county, year, and water source within the United States. We employ a framework we previously developed to establish a companion dataset to our original estimates. The main difference is that we now use the U.S. Geological Survey (USGS) variable 'irrigation — total' to partition PCR-GLOBWB 2 hydrology model estimates, instead of 'irrigation — crop' as used in previous estimates. Our findings for Surface Water Withdrawals (SWW), total Groundwater Withdrawals (GWW), and nonrenewable Groundwater Depletion (GWD) are similar to those of prior estimates but now have better spatial coverage, since several states are missing from the USGS 'irrigation — crop' variable that was originally used. Irrigation water use increases in this study, since more states are included and 'irrigation — total' includes more categories of irrigation than 'irrigation — crop'. Notably, irrigation in the Mississippi Embayment Aquifer is now captured for rice and soy. We provide nearly 2.5 million data points with this paper (3,142 counties; 13 years; 3 water sources; and 20 crops). [ABSTRACT FROM AUTHOR]

Conjunctive use management of water resources is of paramount importance in the backdrop of the growing demand for freshwater resources. With this viewpoint, this study is aimed to present a methodological approach utilizing the combined use of simulation and optimization models for evolving strategies or policies for the management of water resources in a well-field connected to a stream. The proposed methodology incorporates the coupling of the groundwater simulation model with the optimization model for decision-making through the response matrix method. In this study, a numerical groundwater flow model using MODFLOW was used to simulate the response of stream-aquifer interactions. A linear optimization model was formulated to account for the best optimal groundwater withdrawal taking into consideration the allowable drawdown, permissible stream flow depletion, and satisfaction of the water demands. Such management options permit the investigation of alternative strategies for groundwater abstraction in a well-field hydraulically connected to a stream for sustainable development of water resources. The model was applied in a hypothetical well field study area hydraulically connected to a stream and satisfactory results were obtained. The methodology was also very important to understand the tradeoff between groundwater withdrawal and the depletion of flow to the nearby stream. This approach was applied to the Aynalem well field stream-aquifer system which is located in Northern Ethiopia. Results show that groundwater extraction from the Aynalem well field triggers stream flow depletion and it is possible to decrease the stream flow depletion by 3.5–4.5% by adjusting current groundwater withdrawal schedules and configuration of existing wells. [ABSTRACT FROM AUTHOR]

Water scarcity is often triggered by shifting climate patterns as well as rising water usage, yet state-of-the-art Earth system models typically do not represent human water demand. Here we present an enhancement to the Community Earth System Model (CESM) and its land (CLM) and river (MOSART) components by introducing sectoral water abstractions. The new module enables a better understanding of water demand and supply dynamics across various sectors, including domestic, livestock, thermoelectric, manufacturing, mining, and irrigation. The module conserves water by integrating abstractions from the land component with river component flows, and dynamically calculates daily water scarcity based on local demand and supply. Through land-only simulations spanning 1971–2010, we verify our model against known water scarcity hotspots, historical global water withdrawal trends, and regional variations in water use. Our findings reaffirm the role of irrigation in modulating local surface energy fluxes, while emphasizing the importance of including all sectors for water scarcity assessment capabilities. While the model captures global patterns, it also discerns regional nuances, expanding on the conventional focus on irrigation withdrawals in Earth system models (ESMs). Despite its advancements, the model's limitations, such as its exclusive focus on river water abstractions, highlight areas for potential future refinement. This research paves the way for a more holistic representation of human-water interactions in ESMs, aiming to inform sustainable water management decisions in an evolving global landscape. [ABSTRACT FROM AUTHOR]

The consistently low yield turnout of maize on farmers' fields owing to drought and the nutritional challenges attributable to the consumption of white endosperm maize pose a major threat to food and nutritional security in Sub-Saharan Africa (SSA). The objectives of this study were to assess the performance of newly developed extra-early maturing orange hybrids under managed drought and well-watered conditions, compare the outcomes of multiple-trait base index and multi-trait genotype–ideotype distance index selection procedures, and identify drought-tolerant hybrids with stable performance across contrasting environments for commercialization in SSA. One hundred and ninety orange hybrids and six checks were evaluated under managed drought and well-watered conditions at Ikenne for two seasons between 2021 and 2023. A 14 × 14-lattice design was used for the field evaluations under both research conditions. Drought stress was achieved by the complete withdrawal of irrigation water 25 days after planting. Results revealed significant differences among the hybrids under drought and well-watered conditions. Grain yield, ears per plant, and plant aspect under managed drought were correlated to the same traits under well-watered conditions, suggesting that the expression of these traits is governed by common genetic factors. Twenty-nine hybrids were identified as top-performing drought-tolerant hybrids by the multiple-trait base index and the multi-trait genotype–ideotype distance index. Of the selected outstanding 29 hybrids, 34% were derived from crosses involving the tester TZEEIOR 197, demonstrating the outstanding genetic potential of this inbred line. Further analysis of the 29 selected hybrids revealed TZEEIOR 509 × TZEEIOR 197 as the hybrid that combined the most drought-tolerant adaptive traits. However, the hybrids TZEEIOR 526 × TZEEIOR 97, TZEEIOR 384 × TZEEIOR 30, TZEEIOR 515 × TZEEIOR 249, TZEEIOR 510 × TZEEIOR 197, TZEEIOR 479 × TZEEIOR 197, and TZEEIOR 458 × TZEEIOR 197 were identified as the most stable hybrids across drought and well-watered conditions. These hybrids should be extensively tested in multi-location trials for deployment and commercialization in SSA. [ABSTRACT FROM AUTHOR]

Electricity distribution has become one of the most essential components of our society since the beginning of human civilization, relying on an abundant, reliable, and affordable power supply. Fossil fuels dominate the production of electricity (89.57 %), emitting 68.7 % of greenhouse gases, polluting water and soil, and depleting fossil fuels. Future energy needs are faced with growing demand for coal (772 million tonnes by 2040) and fluctuating fuel prices. The Indian power sector withdraws over 20 billion m³ of water, whereby coal power plants use around 35 % of freshwater. Among the seventeen sustainable development goals, Goal 7 emphasizes meeting the demand for electricity, the availability of clean fuels, and mitigating air pollution. In 2021, about 747 TWh of energy consumption was met by coal, oil (92 TWh), and solar energy (25 TWh). Renewable power would meet the world’s growing energy needs, reduce greenhouse gas emissions, boost the economy, and strengthen the society. Therefore, renewable energy has gained global attention as a sustainable electricity source. For this, a thorough examination of the economic and social implications of electricity generation technologies must be carried out. This study discusses how fossil fuel-based electricity generation affects global health and the environment and helps achieve Goal 7 of the sustainable development goals. All sectors must work together to stop global warming and water war and make electricity available worldwide for integrated development. [ABSTRACT FROM AUTHOR]

Water scarcity is a pressing global issue driven by increasing water demands and changing climate conditions. Based on novel estimates of water availability and water use in Chile, we examine the challenges and risks associated with groundwater (GW) withdrawals in the country's central-north region (27–35° S), where extreme water stress conditions prevail. As total water use within a basin approaches the renewable freshwater resources, the dependence on GW reserves intensifies in unsustainable ways. This overuse has consequences that extend beyond mere resource depletion, manifesting into environmental degradation, societal conflict, and economic costs. We argue that the "Day Zero" scenario, often concealed by the uncertain attributes of GW resources, calls for a reconsideration of water allocation rules and a broader recognition of the long-term implications of unsustainable GW use. Our results offer insights for regions worldwide facing similar water scarcity challenges and emphasize the importance of proactive and sustainable water management strategies. [ABSTRACT FROM AUTHOR]

To achieve sustainable development goals in Huangshui River Basin (HRB), strengthening adaptive water resources management under the dual impact of climate change (CC) and human interventions (HI) is of great significance. Multiple mathematical and statistical methods were employed to determine the runoff trend and breakpoint in HRB. The elasticity of CC and HI on the runoff decline and their contributions were quantitatively discerned based on the Budyko hypothesis, complementary method, and SWAT hydrological model. The results show that (1) the runoff showed a decreasing trend, with a runoff breakpoint in 1990; (2) the elasticity coefficients indicated a 1% increase in P, ET0, and n, leading to a 2.19% increase, a 1.19% decrease, and a 1.52% decrease in the runoff, respectively; (3) the Budyko framework determined the contribution of CC and HI to runoff decline in HRB to be 37.98-41.86% and 58.14-62.02%, respectively, and that estimated by SWAT hydrological model to be 38.72 and 61.28%, respectively; (4) HI were the primary factor for runoff decline in HRB, where direct anthropogenic disturbances such as water withdrawals and water conservancy project construction were the main drivers. The findings have important scientific significance for water resources planning and management in HRB. [ABSTRACT FROM AUTHOR]

This article emphasizes the importance of considering the vertical dimension in socio-hydrosystem studies, particularly in relation to groundwater and subsurface flows. The authors argue that vertical connectivity has often been overlooked in previous research and call for better integration of the vertical dimension in socio-hydrological frameworks. They highlight the social and environmental implications of subsurface flows, including impacts on river ecosystems and water quality. The article also discusses the hyporheic zone, the interface between aquifers and rivers, and its importance in understanding and managing water resources. Overall, the article emphasizes the need for interdisciplinary research and a more inclusive and equitable approach to water resource management. [Extracted from the article]

The application of the Thiem equation to support the interpretation of comprehensive long‐term monitoring datasets, made possible through modern datalogging technology, is presented as an alternative to constant‐rate aquifer testing to obtain representative transmissivity estimates in settings where controlled hydraulic testing may be impractical. Water levels logged at regular intervals can be readily converted to average water levels over time periods corresponding to periods of known pumping rates. By regressing average water levels during multiple time periods of known but variable withdrawal rates, steady‐state conditions can be approximated and Thiem's solution applied to estimate transmissivity, without performance of a constant‐rate aquifer test. Although the application is limited to settings where changes in aquifer storage are negligible, by regressing long data sets to parse interferences the method may characterize aquifer conditions over a much wider radius than short‐term, non‐equilibrium tests. As with all aquifer testing, informed interpretation is critical to identifying and resolving aquifer heterogeneities and interferences. [ABSTRACT FROM AUTHOR]

Irrigation activities are important for sustaining food production and account for 70 % of total global water withdrawals. In addition, due to increased evapotranspiration (ET) and changes in the leaf area index (LAI), these activities have an impact on hydrology and climate. In this paper, we present a new irrigation scheme within the land surface model ORCHIDEE (ORganising Carbon and Hydrology in Dynamic EcosystEms)). It restrains actual irrigation according to available freshwater by including a simple environmental limit and using allocation rules that depend on local infrastructure. We perform a simple sensitivity analysis and parameter tuning to set the parameter values and match the observed irrigation amounts against reported values, assuming uniform parameter values over land. Our scheme matches irrigation withdrawals amounts at global scale, but we identify some areas in India, China, and the USA (some of the most intensively irrigated regions worldwide), where irrigation is underestimated. In all irrigated areas, the scheme reduces the negative bias of ET. It also exacerbates the positive bias of the leaf area index (LAI), except for the very intensively irrigated areas, where irrigation reduces a negative LAI bias. The increase in the ET decreases river discharge values, in some cases significantly, although this does not necessarily lead to a better representation of discharge dynamics. Irrigation, however, does not have a large impact on the simulated total water storage anomalies (TWSAs) and its trends. This may be partly explained by the absence of nonrenewable groundwater use, and its inclusion could increase irrigation estimates in arid and semiarid regions by increasing the supply. Correlation of irrigation biases with landscape descriptors suggests that the inclusion of irrigated rice and dam management could improve the irrigation estimates as well. Regardless of this complexity, our results show that the new irrigation scheme helps simulate acceptable land surface conditions and fluxes in irrigated areas, which is important to explore the joint evolution of climate, water resources, and irrigation activities. [ABSTRACT FROM AUTHOR]