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Beyşehir Lake is the largest freshwater lake in the Mediterranean region of Turkey that is used for drinking and irrigation purposes. The aim of this paper is to examine the potential for data-driven methods to predict long-term lake levels. The surface water level variability was forecast using conventional machine learning models, including autoregressive moving average (ARMA), autoregressive integrated moving average (ARIMA), and seasonal autoregressive integrated moving average (SARIMA). Based on the monthly water levels of Beyşehir Lake from 1992 to 2016, future water levels were predicted up to 24 months in advance. Water level predictions were obtained using conventional time series stochastic models, including autoregressive moving average, autoregressive integrated moving average, and seasonal autoregressive integrated moving average. Using historical records from the same period, prediction models for precipitation and evaporation were also developed. In order to assess the model’s accuracy, statistical performance metrics were applied. The results indicated that the seasonal autoregressive integrated moving average model outperformed all other models for lake level, precipitation, and evaporation prediction. The obtained results suggested the importance of incorporating the seasonality component for climate predictions in the region. The findings of this study demonstrated that simple stochastic models are effective in predicting the temporal evolution of hydrometeorological variables and fluctuations in lake water levels.

China is an extremely water-scarce country with an uneven distribution of regional water resources. We define two absolute sustainability indicators, using the multi-regional input‒output (MRIO) model to outline the contribution of China's physical and virtual water transfers in mitigating the problem of regional water boundary-exceeding. Although the overall use of freshwater resources is within the safe operation space, 55% of province's water resource development transgresses the local water planetary boundary. Physical and virtual water transfers effectively mitigate the stress of water supply to the water planetary boundary in China's water-scarce regions. Among them, the role of virtual water transfers occupies the main part. The cost of using physical water in water-receiving regions and the situation of virtual water flowing from water-scarce regions to developed water-rich regions cannot be ignored, and a small number of provinces are responsible for most of the virtual water net imports and exports. The obtained results are helpful for the redistribution of water planetary boundary transgressing responsibilities among provinces and the formulation of absolute sustainable water resources management policies. [ABSTRACT FROM AUTHOR]

The South China Sea throughflow (SCSTF) connects the South China Sea (SCS) with neighboring seas and oceans, transferring surface water of the global thermohaline circulation between the Pacific and Indian oceans. A configuration of the SYMPHONIE ocean model at high resolution (4 km) and including an explicit representation of tides is implemented over this region, and a simulation is analyzed over 2010–2018. Comparisons with in situ and satellite data and other available simulations at coarser resolution show the good performance of the model and the relevance of the high resolution for reproducing the spatial and temporal variability of the characteristics of surface dynamics and water masses over the SCS. The added value of an online computation of each term of the water, heat, and salt SCS budgets (surface, lateral oceanic and river fluxes, and internal variations) is also quantitatively demonstrated: important discards are obtained with offline computation, with relative biases of ∼40% for lateral oceanic inflows and outflows. The SCS water volume budget, including the SCSTF, is analyzed at climatological and seasonal scales. The SCS receives on average a 4.5 Sv yearly water volume input, mainly from the Luzon Strait. It laterally releases this water to neighboring seas, mainly to the Sulu Sea through Mindoro Strait (49 %), to the East China Sea via Taiwan Strait (28 %), and to the Java Sea through Karimata Strait (22 %). The seasonal variability of this water volume budget is driven by lateral interocean exchanges. Surface interocean exchanges, especially at Luzon Strait, are all driven by monsoon winds that favor winter southwestward flows and summer northeastward surface flows. Exchanges through Luzon Strait deep layers show a stable sandwiched structure with vertically alternating inflows and outflows. Last, differences in flux estimates induced by the use of a high-resolution model vs. a low-resolution model are quantified. [ABSTRACT FROM AUTHOR]

Inter-basin water transfer projects are the main measure to address the water deficit crisis caused by uneven distribution of water resources. The current water transfer operation mainly tends to be present in areas with small water transfer costs and is prone to encounter the problem of spatial and temporal imbalances in water allocation. To address these issues, this paper defines a water deficit evenness index (WDEI), aimed at minimizing regional differences in water scarcity and sharing the pressure of water scarcity as a social demand objective. This index is incorporated into a joint optimization model for the Jiangsu section of the South-to-North Water Diversion Project (J-SNWDP), which comprises both the ecological objective of the total water deficit (TWD) and the economic objective of the pumping water (PW). Further, the Nondominated Sorting Genetic Algorithm III (NSGA-III) and multi-attribute decision-making were applied to solve the model and obtain an optimal operation strategy. The results showed the following: (1) the WDEI defined in this paper can mitigate the synchronized water scarcity in certain water users. In typical normal years (wet year and dry year), the WDEI shows a reduction of 94.2 % (81.8 %, 76.7 %) compared to the historical operation strategy. (2) The optimized operation strategy can significantly reduce TWD and PW by 82.06% (37.69 %, 52.36 %) and 45.13 % (3.25 %, 21.51 %) compared with the historical values, respectively, which can improve the water supply satisfaction and reduce the project cost. At the same time, the lake storage capacity of the optimal operation strategy performs well, and the water transfer efficiency of the river is significantly improved. (3) In this paper, targeted optimal operation strategies and potential ways to secure the project tasks are proposed for different natural flow. Overall, it is of great significance to study the water supply equity in the J-SNWDP to alleviate the concentrated water deficit in Jiangsu Province and other similar regions. [ABSTRACT FROM AUTHOR]

The flow routing process plays a crucial role in underpinning the execution of real-time operations within interbasin water transfer projects (IWTPs). However, the water transfer process within the supplying area is significantly affected by the time lag of water flow over extended distances, which results in a misalignment with the water demand process in the receiving area. Hence, there is an imperative need to investigate the flow routing patterns in long-distance water transfer processes. While MIKE11(2014 version) software and the Muskingum method are proficient in simulating flow routing within a water transfer network, they fall short in addressing issues arising from mixed free-surface-pressure flows in water transfer pipelines. This study enhanced the capabilities of the MIKE11(2014 version) software and the Muskingum method by introducing the Preissmann virtual narrow gap method to tackle the challenge of simulating mixed free-surface-pressure flows, a task unattainable by the model independently. This approach provides a clear elucidation of hydraulic characteristics within the water transfer network, encompassing flow rates and routing times. Furthermore, this is integrated with the Muskingum inverse method to compute the actual water demand process within the supplying area. This methodology is implemented in the context of the Han River to Wei River Diversion Project (HTWDP). The research findings reveal that the routing time for the Qinling water conveyance tunnel, under maximum design flow rate conditions, is 12.78 h, while for the south and north main lines, it stands at 15.85 and 20.15 h, respectively. These results underscore the significance of the time lag effect in long-distance water conveyance. It is noteworthy that the average errors between simulated and calculated values for the south and north main lines in the flow routing process are 0.45 m3/s and 0.51 m3/s, respectively. Compared to not using the Preissmann virtual narrow gap method, these errors are reduced by 59.82% and 70.35%, indicating a significant decrease in the discrepancy between simulated and calculated values through the adoption of the Preissmann virtual narrow gap method. This substantially improves the model's fitting accuracy. Furthermore, the KGE indices for the flow routing model are all above 0.5, and the overall trend of the reverse flow routing process closely aligns with the simulated process. The relative errors for most time periods are constrained within a 5% range, demonstrating the reasonability and precision of the model. [ABSTRACT FROM AUTHOR]

The transfer of stagnant water from the basement floor of the waste treatment building at the Fukushima Daiichi Nuclear Power Station is planned because of the possibility of water flowing out of the building if another tsunami occurs. However, the basement floor is installed with high-dose zeolite sandbags as adsorbents for radioactive materials, which renders their removal challenging. In this study, we conduct a field survey and field reproduction as well as develop a robot that can perform zeolite removal based on the results obtained. In addition, we perform verification tests in a full-scale mock-up test environment and extract issues for application to actual equipment. [ABSTRACT FROM AUTHOR]

Understanding the biogeochemical transformations that particulate organic matter (POM) undergoes from production in surface waters to deposition on the seafloor is fundamental for interpreting the paleoceanographic record preserved in sediments. Here we use compound-specific N isotope analysis of amino acids (δ15N AA) from two sediment traps (deployed at 150 m and 250 m water depth) and underlying push-core sediments to investigate temporal and depth related changes in the export flux on a continental shelf basin influenced by a prominent benthic nepheloid layer (BNL). Despite apparent isotopic similarities between traps, molecular data show distinct patterns between the shallower (150 m) and deeper (250 m) sediment traps – specifically, depth-related differences in the relative contributions of particles with different processing histories. The export flux in the shallower trap is dominated by animal sources rather than phytodetritus. Significant microbial degradation in the deeper trap and sediments emphasizes the key roles of resuspension-deposition cycles that are mainly (but not exclusively) facilitated by a thick year-around BNL in the region. The BNL acts as a 'microbial reactor' reworking sinking POM before its ultimate deposition, and also diluting exported material with previously deposited surface sediments. This heavy modification of POM during its passage through and residence in the BNL opens potentially important questions for our current understanding of OC preservation and interpretations of proxy δ15N records in BNL-influenced areas. [ABSTRACT FROM AUTHOR]

Simple Summary: The world's largest water diversion, the South-to-North Water Transfer Project (SNWTP) in China, diverts water from the Danjiangkou Reservoir in the Yangtze River basin to major cities such as Beijing and Tianjin in North China. This water diversion has effectively created an "invasion highway", facilitating the spread of non-native invasive species such as golden mussels (Limnoperna fortunei) to aquatic ecosystems in Beijing. Despite the significance of this development, the dynamics of the spread and colonization patterns of golden mussels in Beijing have remained largely unexplored. In this study, we used environmental DNA (eDNA)-based early detection to conduct comprehensive surveillance across all water bodies in five river basins from 2020 to 2023. Our results revealed a rapid spread of golden mussels in Beijing over the past four years. Starting with four infested sites identified through field surveys in 2019, the count of sites exhibiting positive eDNA signals experienced a gradual rise. Between 2020 and 2022, an additional 10–13 sites were confirmed, followed by a substantial increase to 28 additional sites in 2023. Conventional field surveys confirmed the presence of golden mussels at 16 sites between 2020–2023. To date, golden mussels have rapidly expanded their presence to four out of the five investigated river basins, with only the Daqing River remaining uninfested. The world's largest water diversion, the South-to-North Water Transfer Project (SNWTP) in China, has created an "invasion highway" to introduce invasive golden mussels (Limnoperna fortunei) from the Yangtze River basin to Beijing. To examine the spread and colonization patterns of this newly introduced invasive species, we conducted comprehensive environmental DNA (eDNA)-based early detection and conventional field surveys across all water bodies in five river basins in Beijing from 2020 to 2023. Our results indicated a rapid spread over the past four years. Among the 130 tested sites, the number of sites with positive signals from eDNA analysis exhibited an annual increase: Commencing with four infested sites identified through field surveys in 2019, eDNA analysis detected an additional 13, 11, and 10 positive sites in 2020, 2021, and 2022, respectively, and a substantial rise comprising an additional 28 sites in 2023. Conventional field surveys detected mussels 1–3 years later than eDNA-based analysis at 16 sites. Across all 16 sites, we detected a low population density ranging from 1 to 30 individuals/m2. These findings collectively indicate that the invasions by golden mussels in Beijing are still in their early stages. To date, golden mussels have successfully colonized four out of the five investigated river basins, including the Jiyun River (22.2% positive sites), North Canal River (59.6% positive sites), Chaobai River (40% positive sites), and Yongding River (63.6% positive sites), with the North Canal River and Yongding River being the most heavily infested. Currently, only the Daqing River basin remains uninfested. Given the significant number of infested sites and the ongoing transport of large new propagules via SNWTP, further rapid spread and colonization are anticipated across aquatic ecosystems in Beijing and beyond. Consequently, we call for the proper implementation of effective management strategies, encompassing early detection, risk assessment, and the use of appropriate control measures to mitigate the potential ecological and economic damages in invaded ecosystems. [ABSTRACT FROM AUTHOR]

In order to meet the downstream water demand in the open channel water transfer project, this paper considers it necessary to formulate the control scheme in advance. The design of feed forward control scheme is often complicated, and there are many influencing factors, which make it difficult for dispatchers to make decisions quickly. Based on the storage compensation method, this paper applies feed forward control to the section from Diaohe control gate to Jialihe control gate of the middle route of South-to-North Water Transfer Project. Based on the calculation results of storage compensation, the relationship between the initial flow, water diversion flow and feed forward control time is analyzed, and a fast calculation formula of feed forward control time with single and double variables is established. The influence of different factors on the downstream water level deviation of storage compensation control is explored, and the functional relationship between the initial flow, water diversion flow and the maximum deviation of the downstream water level is obtained. In order to solve the problem that the deviation of the downstream water level under the original storage compensation control is too large in the extreme working condition of engineering operation, the feed forward control of the channel pool is carried out by using the secondary storage compensation rule, which effectively reduces the downstream water level deviation. [ABSTRACT FROM AUTHOR]

Policies that improve drought resilience have heterogeneous effects on agricultural land values. We examine the value of surface water transfers and groundwater resources in a hedonic analysis of agricultural parcels in California. We find that parcels in irrigation districts, which engage in interbasin surface water transfers, experience an increase in value in subsequent years, but the gains are short-lived and unevenly distributed. Value of groundwater stock is higher in parcels outside irrigation districts. We also find that policies to restrict groundwater-substitution-based transfers, which aimed to reduce groundwater open-access externalities, have not been a deterrent against transfers in all areas. [ABSTRACT FROM AUTHOR]

This study presents a 35-year record of total mercury (Hg) concentrations in the detritivore fish Prochilodus nigricans (Curimatã) and the carnivore Cichla pleiozona (Tucunaré), two of the most widely distributed, ecologically important and consumed fish species in the upper Madeira River Basin in the Western Brazilian Amazon. Fish samples from the major Madeira River and marginal lakes and tributaries were compared. Irrespective of site, Hg concentrations were higher in the carnivore fish compared to the detritivore. Hg concentrations increased 5-fold in C. pleiozona in the past three decades, whereas they remained relatively constant in P. nigricans when analyzing the entire 35-year period. When analyzed separately, fish in the main river and marginal lake and tributaries presented the same pattern of Hg variation, with a significant increase in Hg concentrations in the carnivore and in the detritivore in marginal lakes and tributaries but not in the main river. This was in line with the increase in methyl-Hg production in tributaries, mostly associated with deforestation in the past decade in the basin. Although an increase in direct emissions from artisanal gold mining also occurred in the past decade, this caused virtually no impact on fish Hg concentrations, suggesting atmospheric emission and deposition in forests and further export to water systems as an intermediate link with fish Hg concentrations. [ABSTRACT FROM AUTHOR]

In order to increase the capability to understand and quantify the spatial differences in terrestrial water storage (TWS), and to reflect the unique energy balance processes and soil freeze–thaw mechanisms in the Qinghai‐Tibet Plateau (QTP), this study improved the energy balance processes of the water and energy transfer processes model, including its surface radiation calculations and snowmelt module. By integrating these improvements, a water and energy transfer processes model in Qinghai‐Tibet Plateau (WEP‐QTP) for the Yellow River source region (YRSR) is developed. Using the improved WEP‐QTP model to perform simulations, we assessed the daily changes in snow cover, soil moisture (SM), permafrost (PM), and groundwater storage (GWS) in the YRSR. Our analysis revealed an increase in TWS of 0.24 mm/yr from 1961 to 2020. Snow water equivalent (SWE), SM, PM, and GWS have proportional contributions of 8.33%, 216.67%, −154.17%, and 29.17% to the increased TWS, respectively. SM is the primary component of TWS. Temperature (T), precipitation (P), evapotranspiration (E), and solar radiation (Rs) influence the spatiotemporal variations in TWS, as well as those of its components. The increase in P is the primary cause for the rise in TWS, SWE, and SM, while the increase in T predominantly contributes to the decrease in PM. Furthermore, permafrost degradation and climate‐induced warming and humidification lead to increased infiltration, resulting in elevated GWS. [ABSTRACT FROM AUTHOR]

As key water suppliers and natural channels, large rivers have prospered production and trade. However, the emerging trade brought virtual water flows, which will change the physical water distribution. Accordingly, previous policies for water resources management at different scales should be adjusted to take this into account. Taking the Yangtze River Economic Belt (YREB) as a case study, a multi-scale analysis framework is here constructed to analyze the internal, domestic inter-regional and cross-border virtual water flow patterns. That is the base for the following policy design discussions. The World's and Chinese Muti-regional Input-output tables are nested and drivers for regional differences in virtual water flows are further disentangled by Structural decomposition analysis (SDA). Results show that current virtual water flows in the large-river economic belts worsen water distribution inequality if no management controls are implemented. Within the basin, net virtual water flows from the water-deficient reaches to upstream regions with abundant water. At an inter-regional scale, the YREB absorbs a net import of 8.44 × 109 m3 from the north with water shortage, but supplies about 6.7 × 108 m3 to the south. From a cross-border perspective, water stress in the YREB is strengthened by developed countries and alleviated by new emerging countries. Industrial structure effect and scale effect decide the direction of virtual water flows at a national scale, while regional structural effect counts more at a global scale. The water embodied in trades matters when carrying out water rights allocation, water transfer projects and water border adjustment mechanisms. [ABSTRACT FROM AUTHOR]

Inter-basin water transfer (IBWT) projects are an effective means of addressing regional water resource imbalances. However, owing to the long construction cycle, large investment amount, and wide impact range, water diversion projects exhibit delayed and complex benefits, often lacking clear comprehension. In this study, we established a multi-regional comprehensive benefit assessment framework for the IBWT, considering spatiotemporal and multi-dimensional value effects. Using the South-to-North Water Diversion Project (SNWDP) in China as an example, we assessed its comprehensive benefits from 2003 to 2020. The results showed that the comprehensive benefits of the project were USD 207 billion, encompassing economic and ecological benefits, accounting for 71.6% and 28.4%, respectively. In 2020, the benefits of the SNWDP amounted to USD 39.3 billion, with a per-unit area benefit range of USD −1.03 to 4.27. The operation of the SNWDP effectively alleviated groundwater overexploitation in water-receiving areas. However, without the SNWDP, the total loss caused by industrial development limitations due to water scarcity would have been USD 154.3 billion. These results indicate the importance of a practical framework for assessing IWBT project benefits, aiding managers in assessment tasks, and facilitating the prediction and adjustment of project benefits. [ABSTRACT FROM AUTHOR]

Freshwater fish are crucial components of aquatic ecosystems that are affected by a range of anthropogenic activities. Freshwater bodies in Nepal are under different threats affecting biodiversity. Inter-basin water transfer (IBWT) involving damming and diversion of water from one river basin to another is considered a major threat to aquatic biodiversity. Impact assessment of such projects include generation of baseline information on different biotic and abiotic variables. The aim of this study was to generate baseline information on fish diversity from the glacial-fed (Bheri) and the spring-fed (Babai) rivers and their selected tributaries from western Nepal in the wake of the first proposed inter-basin water transfer from the former to the latter. A total of 10 sampling sites, five each from Bheri and Babai River systems, were chosen strategically. Electrofishing was conducted encompassing different seasons in 2018 following the standard method. A total of 32 species with catch per unit effort (CPUE) of 47±24 from Bheri and 42 species with CPUE of 63±52 from Babai River were recorded. Cyprinidae, followed by Nemacheilidae, were the most dominant families in both river systems, and Barilius vagra and Schistura beavani were the most dominant species in both. Species richness and abundance showed a significant difference between rivers, and differences in fish assemblages reflects differences in ecological regimes. Failure to observe migratory species such as Anguilla bengalensis suggests that migratory routes may already have been affected. Of the total 52 species recorded, eight are in the threatened categories of the IUCN Red List and need active conservation measures. The findings provide a reference to assess the impacts of water transfers on fish assemblages in these river systems. [ABSTRACT FROM AUTHOR]

Structural optimization promotes water sterilization by low-voltage pulsed electric field. [Display omitted] • Cu 7 S 4 nanowire coated with N -doped carbon film is beneficial to the anchoring of Ag, and the loaded silver particles enhance the adsorption of O 2. • The successful coating of N -doped carbon layer and Ag particles improved the poor durability and conductivity of Cu 7 S 4. • The work function and electron difference density of different kinds of N -doped Cu 7 S 4 @NC@Ag demonstrate the direction of interface carrier transport. • The removal efficiency can still reach 99% after 8 h of continuous treatment at 6 V and 1000 mL min−1 flow rate. There are many methods of water disinfection, and how to realize low energy consumption, high efficiency and safety sterilization has always been a research hotspot. In this work, Cu 7 S 4 nanowires were grown on copper foam, and coated with N -doped carbon layer and Ag particles, which not only improved the conductivity and local field enhancement regions of the material, but also improved the durability and mechanical stability of Cu 7 S 4. DFT (Density functional theory) calculation shows that different kinds of N doping make the electron difference density and work function of the surrounding C different, which leads to high carrier transport capacity at the interface, and Ag anchored in N -doped carbon films can adsorb O 2. The band gap of the material is 2.12 eV, and the material has the potential to generate superoxide anion under energy excitation. Under the condition of 6 V voltage and 1000 mL min−1 water flow rate, the long-term water filtration sterilization of high-concentration bacteria can be realized, and the removal efficiency can still reach 99% after 8 h continuous treatment. This work has great application prospects for the purification of highly polluted water in the future. [ABSTRACT FROM AUTHOR]

During the operation of proton exchange membrane (PEM) fuel cells, water and heat are produced as two byproducts. A reliable and continuous operation of a PEM fuel cell requires an efficient water removal from the porous structure of the electrodes. In PEM fuel cells, gas diffusion layers (GDL) are used to effectively remove the produced water from the electrodes and also to supply reactant gases across them. The focus of this study is to characterize liquid water percolation within the plane of the GDL by utilizing a nondimensional energy ratio-time scale model (Ce-t ∗). The transport phenomena are investigated for various GDL compressions, GDL samples with the microporous layer (MPL), and a degraded GDL sample. The transition between flow regimes is characterized based on the variation of slopes in Ce-t ∗ curves. The flow regimes were observed to change from fingering and channeling in the capillary fingering regime to macro-transport along with uniform percolation in the stable displacement regime. It was observed that GDL compression can expedite flow regime transition and can cause faster energy dissipation during steady state periods. When MPLs were added to the GDL, the wetted areas were observed to occur at more dispersed locations. Finally, the experiment conducted with a degraded GDL without an MPL demonstrated higher slopes in the Ce-t ∗ curve, indicating more frequent liquid water flooding. This could ultimately result in reduced cell performance. • The study used a nondimensional energy ratio-time scale model to characterize water percolation in the GDL plane. • The transport phenomena was investigated for various GDL conditions. • GDL compression was observed to be able to expedite flow regime transition and cause faster energy dissipation at steady state periods. • Addition of MPLs to GDLs were observed to cause the formation of wetted areas at more dispersed locations. [ABSTRACT FROM AUTHOR]

Using an original methodological and technical approach, we studied the real-time dynamics of radial water transfer in roots and transpiration rate in intact maize plants in response to water stress. It was shown that the response of maize plants to water stress, induced by 10% PEG 6000, was accompanied by changes in the intensity and redistribution of water transfer along different pathways of radial water transport in the roots. It was shown that during the first minutes of water stress impact, the intensity of transcellular and symplastic water transport in the roots decreased with a parallel short-term increase in the transpiration rate in leaves and, presumably, in apoplastic transport in roots. Further, after a decrease in transpiration rate, the intensity of transcellular and symplastic water transport was restored to approximately the initial values and was accompanied by parallel upregulation of some PIP aquaporin genes in roots and leaves, changes in aquaporin localization in root tissues, and changes in xylem sap pH. Under water stress conditions, cell-to-cell water transport in roots becomes dominant, and aquaporins contribute to the simultaneous regulation of water transport in roots and shoots under water stress. [ABSTRACT FROM AUTHOR]

Long-distance water transfer is a critical engineering measure to rectify disparities in water resource distribution across regions. The effective operation and safety of such projects are paramount to their success, as localized issues can have cascading consequences, potentially disrupting the entire network. Conventional ground-based monitoring methods have limitations in measuring the deformation of large-scale structures. In this paper, InSAR is employed to monitor the deformation of the Shuangwangcheng (SWC) Reservoir, which features a long embankment dam as part of the South-to-North Water Diversion Project in China. We utilize data from both Sentinel-1 and TerraSAR-X satellites to derive 7-year deformation. Results reveal that the entire dam experiences continuous subsidence, with the maximum deformation in the line-of-sight direction measuring ~160 mm. While minor differential settlements are noted in different sections of the dam, the gradient is not significant due to the dam's substantial length. The InSAR deformation results from multiple geometries demonstrate good consistency, with the highest correlation observed between the Sentinel-1 ascending and descending datasets, exceeding 0.9. Validation against the GNSS observations of the three sites on the SWC Dam shows the accuracy of InSAR displacements is ~8 mm. Water level changes do impact deformation, but consolidation settlement appears to be the primary controlling factor during the monitoring period. This study underscores the potential of InSAR in long-distance water transfer projects and highlights that spatially continuous deformation is the most significant advantage. [ABSTRACT FROM AUTHOR]

In open-channel water transfer projects, hydrodynamic modeling has been one of the tools commonly used by the scheduling staff to perceive the changes in the water condition of the channel. The reliability of the flow monitoring data has not been guaranteed due to restrictions in the flow monitoring method. Flow monitoring errors directly reduce the accuracy of hydrodynamic modeling calculations, making it impossible to accurately grasp the real-time changes in the internal water conditions of the channel. In this paper, by utilizing the characteristics of the hydrodynamic model itself, which can be solved discretely with multiple boundary conditions, the method of correcting the boundary anomaly data is proposed by changing the combination of hydrodynamic boundaries. This solves the problem of the inaccuracy of hydrodynamic model calculations due to errors in the monitoring data and improves the accuracy of the hydrodynamic model calculations. In the actual operation process, it is found that the method proposed in this paper solves the problem of hydrodynamic model misalignment caused by flow observation errors by correcting the flow during the flow adjustment period, which greatly improves the calculation accuracy of the hydrodynamic model. Secondly, for a stable flow period, the method proposed in this paper can quickly capture and correct the local monitoring of abnormal data and improve the overall hydrodynamic simulation accuracy. [ABSTRACT FROM AUTHOR]

Climate change and evolving water management practices may have a profound impact on hydropower generation. While hydrological models have been widely used to assess these effects, they often present some limitations. A major challenge lies in the modeling of release decisions for hydropower reservoirs, which result from intricate trade-offs, involving power sector dispatch, competing water uses and the spatial allocation of power generation within the grid. To address this gap, this study introduces a novel demand-based approach for integrating hydropower within the routing module of land surface models. First, hydropower infrastructures are placed in coherence with the hydrological network and links are built between hydropower plants and their supplying reservoirs to explicitly represent water transfers built for hydropower generation. Then, coordinated dam operation is simulated by distributing a prescribed electric demand to be satisfied by hydropower over the different power plants on the power grid, while considering the operational constraints associated with the multipurpose nature of most dams. To validate our approach, this framework is implemented within the water transport scheme of a land surface model and assessed with the case study of the French electrical system. We drive the model with a high-resolution atmospheric reanalysis and prescribe the observed national hydropower production as the total power demand to be met by hydropower infrastructures. By comparing the simulated evolution of the stock in reservoirs to the observations, we find that the model simulates realistic operations of reservoirs and successfully satisfies hydropower production demands over the entire period. We highlight the roles of uncertainties in estimated precipitation and of the limited knowledge of hydropower networks on the estimation of production. Finally, we show that such an integration of hydropower operations in the model improves the simulations of river discharges in mountainous catchments affected by hydropower. [ABSTRACT FROM AUTHOR]

Water can be redistributed physically and virtually. We explored water allocation optimization to mitigate water stresses by constructing a physical–virtual dual water system and optimizing the 1987 Yellow River water allocation scheme. We calculated the virtual water volume, identified the virtual in-basin, out-of-basin, and export water volumes, and compared the total regional water demand (i.e., combined physical and virtual water volumes) with regional water planetary boundaries to optimize basin water allocation schemes. Virtual water accounted for > 90% of the total regional demands, whereas physical flows did not significantly impact them. Moreover, allocation quotas for Qinghai and Inner Mongolia should be reduced by 0.113 and 1.005 billion m3, respectively, for sustainability. Furthermore, improving the efficiency of water-intensive sectors and limiting virtual water outflows from heavy industry to out-of-basin sectors are vital to water intensification. Increased attention should be directed toward physical–virtual water demands than the current focus on supply-oriented water allocation. [ABSTRACT FROM AUTHOR]

• 11001 t of N, 68 t of P, and 73528 t of S were delivered in 2021. • Atmospheric deposition contributes 9% for N and 21% for P input to the Middle Route. • There were 988 t of N, 29 t of P and 2,540 t of S accumulated in the main channel. Nutrient levels in the artificial channel constructed for the Middle Route Project are significant indicators of water quality safety and aquatic ecological integrity for this large, inter-basin scheme. However, the distribution and transport of nutrients along the channel were poorly understood. Based on a time-series dataset as well as mass balance and material flow analysis methods, the water and nutrient transport fluxes in the Middle Route of the South-to-North Water Diversion Project were identified in this study. The results indicate that the nutrient concentrations varied considerably with time, but there was no significant difference among the 30 stations of the main channel. Seasonal temperature difference was the major factor in the large fluctuations of water quality indicators over time. The nutrient loadings varied with the water volume outputs from the main channel to the water-receiving cities. Atmospheric deposition was an important source of nutrients in the main channel, accounting for 9.13%, 20.6%, and 0.635% of the nitrogen, phosphorus, and sulfur input from the Danjiangkou Reservoir, respectively. In 2021, a net accumulation of 988 tons of N, 29 tons of P, and 2,540 tons of S, respectively, were present in the main channel. The increase of these external and internal nutrient loadings would cause water quality fluctuation and deterioration in some local sections of the main channel. Our study quantified the spatial and temporal patterns of nutrient transport in the Middle Route and revealed the ecological effects on the aquatic environment, assisting authorities on the project to develop effective water conservation strategies. [Display omitted] [ABSTRACT FROM AUTHOR]

Aiming at the shortcomings of traditional water level prediction methods such as insufficient information mining ability and unclear mechanism of heuristic algorithms, this paper proposes for the first time a water level prediction method based on blockchain technology fused with long short-term memory (LSTM) network. The method utilizes blockchain and LSTM neural network to build a combined model, and directly uploads monitoring data such as import and export water flow and water level to predict the water level, which avoids the secondary error brought by the indirect calculation of flow. In this paper, the flow compensation strategy is proposed for the first time, and the monitoring data with large deviations are compensated accordingly to reduce the prediction error from the source. The results show that the combined Blockchain-LSTM model has the smallest prediction error after adopting the compensation strategy, with the MAE of 0.290 and the RMSE of 0.490, which are smaller than those of other models, and has high prediction accuracy and practicability, which provides technical support for real-time scheduling of the South-to-North Water Diversion Reservoir. [ABSTRACT FROM AUTHOR]

The sluggish electron transfer kinetics in electrode polarization driven oxygen evolution reaction (OER) result in big energy barriers of water electrolysis. Accelerating the electron transfer at the electrolyte/catalytic layer/catalyst bulk interfaces is an efficient way to improve electricity-to-hydrogen efficiency. Herein, the electron transfer at the Sr3Fe2O7@SrFeOOH bulk/catalytic layer interface is accelerated by heating to eliminate charge disproportionation from Fe4+ to Fe3+ and Fe5+ in Sr3Fe2O7, a physical effect to thermally stabilize high-spin Fe4+ (t2g³eg¹), providing available orbitals as electron transfer channels without pairing energy. As a result of thermal-induced changes in electronic states via thermal comproportionation, a sudden increase in OER performances was achieved as heating to completely suppress charge disproportionation, breaking a linear Arrhenius relationship. The strategy of regulating electronic states by thermal field opens a broad avenue to overcome the electron transfer barriers in water splitting. [ABSTRACT FROM AUTHOR]

This viewpoint contends that the Arizona project, aimed at constructing a mega-desalination plant in the Gulf of California (also known as the Sea of Cortez), in Mexico, with the intention of exporting desalinated water to Arizona, poses an imminent threat to the environment. It points out that this project lacks a necessary environmental impact statement and has not received approval from Mexican authorities. Additionally, there appears to be no sufficient provision for compensating for the potential harm to natural resources, and the approval by the Mexican authorities remains unlikely. [ABSTRACT FROM AUTHOR]

The Weddell Gyre is one of the dominant features of the Southern Ocean circulation and its dynamics have been linked to processes of climatic relevance. Variability in the strength of the gyre's horizontal transport has been linked to heat transport toward the Antarctic margins and changes in the properties and rates of export of bottom waters from the Weddell Sea region to the abyssal global ocean. However, the precise physical mechanisms that force variability in the Weddell's lateral circulation across different time scales remain unknown. In this study, we use a barotropic vorticity budget from a mesoscale eddy active model simulation to attribute changes in gyre strength to variability in possible driving processes. We find that the Weddell Gyre's circulation is sensitive to bottom friction associated with the overflowing dense waters at its western boundary. In particular, an increase in the production of dense waters at the southwestern continental shelf strengthens the bottom flow at the gyre's western boundary, yet this drives a weakening of the depth-integrated barotropic circulation via increased bottom friction. Strengthening surface winds initially accelerate the gyre, but within a few years the response reverses once dense water production and export increases. These results reveal that the gyre can weaken in response to stronger surface winds, putting into question the traditional assumption of a direct relationship between surface stress and gyre strength in regions where overflowing dense water forms part of the depth-integrated flow. [ABSTRACT FROM AUTHOR]

In power applications, convection plays a dominant position in the transport of strength for the proper design to attain higher warmth transfer quotes. Where in the fluid movement is genuinely induced via density gradients. This has a look at what is involved with transient convection in an isosceles-superimposed triangular enclo sure. The walls were angled at θ = 45°. Critical Rayleigh numbers have been obtained: Ra = 106, especially for the fluid crushed between the two triangles where we can visualize the critical convection transaction between the air and water. The consequences in the quantitative dimension of average Nusselt quantity change and qualitative visualization of streamline and isotherms are examined. The air and water streamlines and the temperature fields had been obtained for the Rayleigh numbers 10³ ≤ Ra ≤ 108. Furthermore, the water fluid's natural convection case has the best heat transfer performance at the water fluid, whereas the dilatant fluid exhibits the lowest heat transfer performance. Heat transfer from the bottom to the top can be significantly improved by the triangle shape at first in a smooth and harmonious manner, and then it turns into a more complex and disorderly shape when the water reaches high temperatures. [ABSTRACT FROM AUTHOR]

The adsorption and reactions of water with surfaces is of immense importance in catalysis and corrosion. Charge transfer of ion scattering is sensitive to changes of work function and electronic structure caused by adsorption of water on a surface. In this work, as the model systems of metals and semiconductors the water adsorbed copper and silicon surfaces have been chosen and the research progress of charge transfer of the negative and positive ion scattering in our group were reviewed. [ABSTRACT FROM AUTHOR]

In global hydrological models, river discharge is accumulated by following the river network, which presumes that there is one downstream destination for each grid. Implementing "diversions" where there are multiple downstream destinations, such as bifurcations and inter-basin water transfers, requires an extension of river routing algorithms. Previous global water resources models that implemented diversions typically used a semi-implicit numerical scheme where river discharge should be calculated in an upstream-to-downstream order. The major obstacle to flexible application to any river network with diversions was that ad-hoc modification of the model's code was required because the river sequence map to specify calculation order was developed without considering diversions. To overcome this limitation, we developed two new river routing algorithms that can generally represent diversions. One is automatically updating river sequence considering diversions and the other is introducing the Forward Time Centered Space scheme. The former has the advantage of stability under longer time steps, while the latter's strength lies in its easy implementation and applicability where backwater happens. We confirmed that both algorithms efficiently handle the complex canal network in the Indus River. These approaches allow us to flexibly implement diversions in river routing algorithms. [ABSTRACT FROM AUTHOR]

Copyright of Ecological Applications is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Talus, as the product of movement and accumulation along the slope after the cracking of cliffs or steep rock walls, is a common landform in the mountain periglacial environment. Significant thermal anomalies within talus have been widely reported to be a result of cooling effects. During the cold season, the increased temperature difference between talus and the ambient environment strengthens the intensity of convection (vertical flows) and transforms into upward advection (lateral flows) and exhausts the internal warm current. During the warm season, heat is concentrated on the surface of the talus, and the internal dominant cold current moves downward along the slope by advection. The principle of the proactive cooling effects of talus has been widely utilized in railway construction within permafrost regions as embankments to alleviate degradation of the underlying permafrost. However, limited model studies have examined the cooling effects of blocky debris in nature, and in situ observations are rare. Therefore, it will be important to increase observations and develop process‐based models that couple heat conduction, convection/advection, water transfer processes, and even the latent heat of phase change. This will help to better understand the extent of the cooling effects and its impact on the thermal regime of permafrost. [ABSTRACT FROM AUTHOR]

Coastal estuaries globally, including the San Francisco Estuary (SFE), are experiencing significant degradation, often resulting in fisheries collapses. The SFE has undergone profound modifications due to population growth, industrialization, urbanization and increasing water exports for human use. These changes have significantly altered the aquatic ecosystem, favouring invasive species and becoming less hospitable to native species such as the longfin smelt (Spirinchus thaleichthys). With longfin smelt abundance declining to <1% of historical numbers, there is a pressing need for laboratory-based experiments aimed at investigating the effects of varying environmental conditions on their stress response and physiology. This study explored the impact of temperature (11 and 14°C) and turbidity maintained with algae (1, 4 and 11 nephelometric turbidity units (NTU)) on the physiological condition of juvenile longfin smelt. Fish were sampled after 2 and 4 weeks in experimental conditions and analysed for whole-body cortisol, glucose, lactate and protein. Condition factor was calculated using length and weight measurements. Critical thermal maximum trials were conducted to assess how prior rearing conditions affected upper thermal tolerance. Cortisol levels were significantly higher in fish held in low-turbidity conditions, whilst glucose levels were significantly greater at lower temperatures and higher turbidities. Protein-to-mass ratios were significantly greater in higher turbidity conditions, with a significant interaction between temperature and turbidity further influencing these ratios. Moreover, 14°C led to diminished condition factors but increased upper thermal tolerances (26.3 ± 0.05 vs 24.6 ± 0.18) compared to longfin smelt at 11°C, highlighting a potential trade-off between the induction of defense mechanisms and subsequent reductions in energy and growth. Data suggest that cooler temperatures (11°C) and elevated turbidities (11 NTU) can benefit juvenile longfin smelt by reducing stress and enhancing growth and energy. These findings hold significant implications for informing and optimizing future endeavours in the culturing and conservation of this species. [ABSTRACT FROM AUTHOR]

Copyright of Tikrit Journal of Engineering Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, hydrophilic cotton (CO) yarn and hydrophobic cross-section polyester (PET) filaments were used to prepare single-layer interwoven fabrics (CO/PET fabrics) with plain, 3/1 twill, and 8/5 satin to formulate a hydrophobicity–hydrophilicity gradient across the fabric for obtaining a good water transfer ability. The CO fabrics and PET fabrics were prepared for comparison. The contact angle and thermo-physiology properties of the fabrics, including the wicking property, moisture management ability, drying property, air permeability and water vapor permeability, thermal property, and dynamic cooling property, were investigated. The results show that the asymmetric hydrophobicity–hydrophilicity characteristic can be formed across CO/PET fabric with 3/1 twill and 8/5 satin. This can improve the water transfer ability from the inside to the outside of the fabrics, and the longer the floating length of the fabric is, the stronger the water transfer ability is. These two fabrics also exhibit excellent wicking properties, overall moisture management capability, and thermal comfort, and have good permeability, drying properties, and dynamic cooling properties compared to the corresponding fabrics. As a result, these two CO/PET interwoven textiles are more suitable for application as clothes worn in summer. The interweaving technique combining hydrophilic and hydrophobic yarns is an easy and cost-effective method to prepare fabrics that meet summer requirements. This work provides insight into the thermal and moisture comfort property of interwoven fabrics for summer garments. [ABSTRACT FROM AUTHOR]

The sinking of zooplankton fecal pellets is a key process in the marine biological carbon pump, facilitating the export of particulate organic carbon (POC). Here, we analyzed zooplankton fecal pellets collected by two time-series sediment traps deployed on mooring TJ-A1B in the northern South China Sea (SCS) from May 2021 to May 2022. The results show a seasonal variability in both fecal pellet numerical (FPN) flux and fecal pellet carbon (FPC) flux, with peaks in November to April and June to August. It implies that the fecal pellet flux is largely regulated by the East Asian monsoon system. Vertical analysis further shows that FPN and FPC fluxes are higher at 1970 than at 500 m water depth, with larger pellets occurring in the deeper water, indicating a significant influence of mesopelagic and bathypelagic zooplankton community and lateral transport on deep-sea FPC export. However, the biovolume of amorphous pellets decreases significantly from 500 to 1970 m water depth, implying that these fecal pellets are broken and fragmented during the sinking process, possibly due to zooplankton grazing and disturbance by deep-sea currents. The contribution of fecal pellets to total POC export in the northern SCS is on average 3.4 % and 1.9 % at 500 and 1970 m water depth, respectively. This study highlights that the sinking fate of fecal pellets is regulated by marine primary productivity, deep-sea-dwelling zooplankton communities, and deep-sea currents in the tropical marginal sea, thus providing a new perspective for exploring the carbon cycle in the world ocean. [ABSTRACT FROM AUTHOR]

Submarine canyons enhance shelf–slope sediment exchange and influence hydrodynamic processes, with consequences for biogeochemical cycles. This work documents variations in the vertical export of biogenic matter on the northern shore of the lower St. Lawrence Estuary (LSLE, Quebec, eastern Canada), which is characterized by the presence of an active submarine canyon system. A total of three moorings were deployed from November 2020 to September 2021. One nearshore mooring (PDMc) was deployed in the main axis of the Pointe-des-Monts (PDM) canyon system and was equipped with an acoustic Doppler current profiler (ADCP), and two moorings equipped with sediment traps were deployed in the distal PDM canyon system (PDM-154, PDM-224) and offshore Baie-Comeau (BC-133). The ADCP data revealed the occurrence of a minor sediment remobilization event (December 2020) and a small turbidity current (February 2021) in the canyon. Concurrent elevated fluxes of total particulate matter, particulate organic carbon, particulate nitrogen, and chloropigments showed that these events left a signature in sediment traps PDM-154 and PDM-224 located > 2.6 km further offshore by enhancing lateral dispersion of resuspended sediments. The composition of diatom and dinoflagellate assemblages was similar in the canyon system and offshore BC, but the diatom bloom occurred 2 weeks earlier (in mid-April) at the PDM site. A bloom of the potentially toxic diatom Pseudo-nitzschia seriata was also observed during the second half of September 2021 at the BC site. Annual diatom and dinoflagellate fluxes were almost 2 times lower at the PDM site than at the BC site, possibly due to differences in riverine input and the structure of the water column, as well as increased sediment input and resuspension at the PDM site, leading to limited light availability. This study notably helps identify the relationship between near-bed canyon processes and biogenic matter export in the water column, thereby directly influencing the ecosystem offshore PDM. The study period further covered an anomalously nearly ice-free winter, and thus, in the context of climate change, it provides valuable insight into future trends of biogenic matter export in the LSLE. [ABSTRACT FROM AUTHOR]

Proton‐coupled electron transfer (PCET) plays a crucial role in a diverse array of natural and artificial energy conversion processes. Herein, we will introduce the fundamentals of electrochemical PCET with a focus on its role in water splitting. Besides, perspectives of future development of PCET are presented with regard to the investigation of reaction mechanisms and the design of advanced electrocatalysts. [ABSTRACT FROM AUTHOR]

The North Atlantic meridional overturning circulation and its variability are examined in terms of the overturning in density space and diapycnal water mass transformation. The magnitude of the mean overturning is similar to the surface water mass transformation, but the density and properties of these waters are modified by diapycnal mixing. Surface waters are progressively densified while circulating cyclonically around the subpolar gyre, with the densest waters and deepest convection occurring in the Labrador Sea and Nordic Seas. The eddy-driven interaction between the convective interior and boundary currents is a key to the export of dense waters from marginal seas. Due to the multitude of pathways of dense waters within the subpolar gyre, as well as mixing with older waters, waters exiting the subpolar gyre have a wide range of ages, with a mean age on the order of a decade. As a result, interannual changes in water mass transformation are mostly balanced locally and do not result in changes in export to the subtropics. Only persistent changes in water mass transformation result in changes in export to the subtropics. The dilution of signals from upstream water mass transformation suggests that variability in export of dense waters to the subtropics may be controlled by other processes, including interaction of dense waters with the energetic upper ocean. This article is part of a discussion meeting issue 'Atlantic overturning: new observations and challenges'. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H2S) has many physiological and pathological roles in the human body. Sodium hydrosulfide (NaHS) is widely used as a pharmacological tool for assessing H2S effects in biological experiments. Although H2S loss from NaHS solution is a matter of minutes, some animal studies use NaHS in solution as an H2S-donating compound in drinking water. This study addresses whether 30 μM NaHS in drinking water prepared in rat/mouse water bottles remains stable for at least 12–24 h, as presumed by some authors. NaHS solutions (30 μM) were prepared in drinking water and immediately transferred to rat/mice water bottles. Samples were obtained from the tip of water bottles and from inside of the bottles at 0, 1, 2, 3, 4, 5, 6, 12, and 24 h for sulfide measurement using the methylene blue method. Furthermore, NaHS (30 μM) was administered to male and female rats for two weeks, and serum sulfide concentrations were measured every other day in the first week and at the end of the second week. NaHS solution was unstable in the samples obtained from the tip of water bottles; it declined by 72% and 75% after 12 and 24 h, respectively. In the samples obtained from the inside of the water bottles, the decline in the NaHS was not significant until 2 h; however, it decreased by 47% and 72% after 12 and 24 h, respectively. NaHS administration did not affect serum sulfide levels in male and female rats. In conclusion, NaHS solution prepared in drinking water can not be used for H2S donation as the solution is unstable. This route of administration exposes animals to variable and lower-than-expected amounts of NaHS. [ABSTRACT FROM AUTHOR]

Soil–hydrophysical research substantiating the mathematical models of water movement, taking into account the soil heterogeneity, due to the vertical change in texture, is considered. The vertical movement of water on large-size lysimeters of the Federal Scientific Center of Agroecology of the Russian Academy of Sciences (Volgograd) was studied. The influence of statistical heterogeneity of hydrophysical parameters of lysimeter substrates was studied on models of water transfer dynamics and formation of gravitational runoff developed in the HYDRUS-1D software package. The change in texture along the vertical profile of the lysimeters and the related variability of the main hydrophysical characteristic or water retention curve (WRC) were taken into account. The textural heterogeneity of the substrates was estimated by the scaling method, according to the scale factors of the WRC parameters, assuming a normal probability distribution of the logarithms of the pore space capillary radii between soil particles. The effect of texture on water holding capacity, boundary and initial conditions, intensity of gravitational runoff and cumulative accumulation of water were studied. [ABSTRACT FROM AUTHOR]

To study the effect of water jet assisted laser machining and waterless auxiliary laser machining of SiC on the processing results, the effects of water jets with different jet velocities on the impact force and convective heat transfer of water jet assisted laser processing are simulated by finite element (FE) modelling. During the experiment the laser parameters were kept unchanged while the jet velocity was changed. A comparison experiment of water jet assisted laser machining and water jet assisted laser machining of SiC was carried out. The results show that with the increased water jet velocity, the impact pressure and convective heat transfer of water jet impact material are gradually enhanced. When there is no water jet assisted laser machining of SiC material, there are more slag and recondensation layers on both sides and notches of the tank body, the heat affected zone (HAZ) is larger, and the surface processing quality is poor. Compared with water jet assisted laser machining, there are fewer almost no slag and re-condensation layers on both sides and notches of the tank, the HAZ is reduced, and the quality of the processing groove is better. In the 45° water jet assisted laser machining, the processing effect is better when the water jet velocity reaches 20 m/s. Water jet assisted laser machining can obtain better processing quality than waterless auxiliary laser machining. [ABSTRACT FROM AUTHOR]

Water transfers through a multilayered aquifer system are difficult to characterize. This study explores whether the conceptual model of water mixing at depth can be extrapolated over a hydrosystem extended across several tens of kilometers and including multiple aquifer layers. The processes are investigated using a combination of isotope tracers and piezometric monitoring over 10 years. The goal of this approach is to better understand how water transfer occurs throughout a complex and poorly documented hydrosystem of the Mahafaly Plateau in southwestern Madagascar. The results show a clear smoothing of isotopic variability with depth, associated with a smoothing of the recharge peaks. Isotopic values are strongly variable in the near surface (from -6.8 to -2.5‰ 18O) and stabilize at a critical depth (near 20 m) at around -4.7‰ 18O. These results indicate high vertical flows through the aquifer system, where there is neither obvious dominant recharge via preferential pathways nor lateral mixing. Such a strong smoothing effect on groundwater isotopic variability with depth has been rarely observed so clearly over a large spatial scale. These results provide information on a remote groundwater flow system at a scale pertinent to groundwater resource assessment. The results also indicate that the Neogene aquifers of the Mahafaly Plateau are poorly connected with other water resources (rivers, old sedimentary formations) except for the percolation of water towards the deep Eocene karst. This means that groundwater resources in the Ankazomanga Basin are limited and that it is essential to understand and quantify recharge for sustainable groundwater management. [ABSTRACT FROM AUTHOR]

For millennia, cities have invested in inter- and intra-regional infrastructure to transfer water from neighboring sources. This study analyzed how climate change can affect the balance of water supply and demand in the megacity of Istanbul, Turkey over the next 100 years. The Water Evaluation and Planning (WEAP) method was used to examine three long-term scenarios for water availability based on differences in water supply: 1) a continuation of current supply sources; 2) expansion of water resources based on construction of additional water infrastructure; and 3) reduction in water resources to rely on local resources only. Our findings show that extending dependence on inter-regional water supplies is not only likely to increase Istanbul's own water insecurity, but may also affect the human populations, biodiversity and economies of neighboring cities, representing an unsustainable solution that can only exacerbate regional water insecurity in the long run. [ABSTRACT FROM AUTHOR]

China's Yellow River, the nation's second-longest, grapples with severe water scarcity, impeding the high-quality development of its basin. Our study meticulously examines the intricate virtual water trade network inside and outside the basin, providing essential insights to combat its acute water scarcity. We calculated water consumption coefficients for seven pivotal sectors across diverse Chinese provinces, forming the foundational data for quantifying virtual water trade both inside and outside the basin. Utilizing the 2015 Multi-Regional Input-Output Table, we assessed the Yellow River Basin's reliance on external water resources. Despite enduring chronic water scarcity, the basin annually exports a substantial 27.2 billion m3 of virtual water, equivalent to half of its yearly runoff. This outflow predominantly flows to the economically advanced eastern coastal region, with Agriculture and Manufacturing sectors dominating. Significantly, an irrational industrial layout leads to a substantial transfer of virtual water from economically disadvantaged areas to more affluent regions, exacerbating water scarcity in the basin's less privileged areas. Our study yields critical insights for mitigating water shortages in the Yellow River Basin and provides a transferrable framework for regions worldwide grappling with analogous challenges. [ABSTRACT FROM AUTHOR]

Globally, a persistent decline of freshwater availability has been identified over a number of intensively irrigated agricultural regions. Large‐scale inter‐basin water transfer (IBWT) has been suggested as a key tool for stabilizing regional terrestrial water storage (TWS). However, IBWT projects are prohibitively expensive, and their large‐scale cost effectiveness remains unclear. Here we quantify the IBWT impacts on TWS trends in the North China Plain (NCP), a global hotspot for TWS depletion and IBWT. Based on in‐situ observations, remote sensing, and water balance principles, we provide a framework to disentangle complex climate and anthropogenic impacts on NCP TWS. Results show that the NCP TWS depletion rate was significantly attenuated in 2015–2021, which is primarily attributable to recently enhanced IBWT. Otherwise, the average NCP TWS would currently be 94.9 ± 4.9 mm (or 12.2 ± 0.6 km3) lower. However, the positive effect of IBWT is partly offset by increased crop water consumption (−24.1 ± 5.2 mm or −3.1 ± 0.7 km3). IBWT and agricultural management (i.e., reducing crop density) are both necessary for stabilizing future NCP TWS. Otherwise, a TWS declining trend exceeding 100 mm/year may occur under elevated CO2 conditions. As such, this study verifies the feasibility and effectiveness of IBWT for mitigating regional water shortages, as well as the crucial role of agricultural management in stabilizing regional TWS. Key Points: A new framework for reconstructing terrestrial water storage (TWS) is proposedThis framework physically distinguishes climate and human impacts on TWS anomaly variationsInter‐basin water transfer and agriculture management are critical for stabilizing TWS over the North China Plain [ABSTRACT FROM AUTHOR]