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Groundwater plays a crucial role in sustaining global food security but is being over‐exploited in many basins of the world. Despite its importance and finite availability, local‐scale monitoring of groundwater withdrawals required for sustainable water management practices is not carried out in most countries, including the United States. In this study, we combine publicly available datasets into a machine learning framework for estimating groundwater withdrawals over the state of Arizona. Here we include evapotranspiration, precipitation, crop coefficients, land use, annual discharge, well density, and watershed stress metrics for our predictions. We employ random forests to predict groundwater withdrawals from 2002 to 2020 at a 2 km spatial resolution using in situ groundwater withdrawal data available for Arizona Active Management Areas (AMA) and Irrigation Non‐Expansion Areas (INA) from 2002 to 2009 for training and 2010–2020 for validating the model respectively. The results show high training (R2≈0.9$$ {R}^2\approx 0.9 $$) and good testing (R2≈0.7$$ {R}^2\approx 0.7 $$) scores with normalized mean absolute error (NMAE) ≈ 0.62 and normalized root mean square error (NRMSE) ≈ 2.34 for the AMA/INA region. Using this method, we spatially extrapolate the existing groundwater withdrawal estimates to the entire state and observe the co‐occurrence of both groundwater withdrawals and land subsidence in South‐Central and Southern Arizona. Our model predicts groundwater withdrawals in regions where production wells are present on agricultural lands and subsidence is observed from Interferometric Synthetic Aperture Radar (InSAR), but withdrawals are not monitored. By performing a comparative analysis over these regions using the predicted groundwater withdrawals and InSAR‐based land subsidence estimates, we observe a varying degree of subsidence for similar volumes of withdrawals in different basins. The performance of our model on validation datasets and its favourable comparison with independent water use proxies such as InSAR demonstrate the effectiveness and extensibility of our combined remote sensing and machine learning‐based approach. [ABSTRACT FROM AUTHOR]

Metals are commonly characterized as commodities, as there are little to no differences across products. Despite this traditional view, there has been an increasing attempt to assess mineral production, including socioeconomic and environmental impacts, besides their financial performance. In this line, sustainability reports have been the fundamental tool to provide transparent and public information on these impacts, varying in quality and quantity across companies. Based on this premise, we analyze several indicators to assess the potential for differentiation in the copper mining industry. We consider mine site-level data on water withdrawal and greenhouse gas (GHG) emissions, publicly available from sustainability reports from companies operating in 20 countries representing almost 80% of global production. Socioeconomic and governance data is available nationally, which limits more detailed analysis in these aspects. Data gathering indicates that since 2017, copper companies have stabilized regarding the availability of data provided in sustainability reports. Results for copper mining show that water withdrawal is a leading indicator in terms of differentiation potential. Differentiation is higher when continental water is considered, creating a significant incentive for companies to invest in alternative water sources. Sustainability differentiation in copper mining disproportionately affects low-income countries when socioeconomic aspects are considered, mainly if governance measures are used. In this sense, high-income countries are more likely to support product differentiation based on responsible production standards. • Differentiation potential in copper mining through sustainability indicators. • Limited public data to differentiate mining based on broader environmental aspects. • Indicators reveal that water source provides higher differentiation. • Larger mines do not show better sustainability performance in aggregated analysis. [ABSTRACT FROM AUTHOR]

• Detailed modeling of water cycling system within green hydrogen chain. • Considering various water consumption, withdrawal, blowdown, and generation. • Closed-loop water system encompassing power-to-gas and gas-to-power. • Modeling and sizing a storage-integrated RO-based desalination plant. • Integrating water-conscious H2 subsystem in the planning of remote microgrids. • Testing the model with the real-life data and versatile sensitivity cases. Water plays a pivotal role in the production of green hydrogen, requiring meticulous management. Approximately 10 L of water are needed to produce one kilogram of hydrogen through electrolysis. Furthermore, roughly 10–20 L per kilogram are required for process cooling. A share of this water consumption is blowdown, which can be recirculated, while water is also generated as a byproduct of energy conversion in fuel cell. Although green hydrogen production via renewable-supplied electrolysis is a crucial focus for sustainable energy systems, its water implications are often overlooked. Understanding and addressing the water-hydrogen nexus as the global energy transition progresses is pivotal for successful green hydrogen deployment. This paper highlights the role of water in green hydrogen production to bridge this gap. Accordingly, it presents a systematic model of water generation, withdrawal, and blowdown cycles in the power-to-gas and gas-to-power processes within a green hydrogen chain system for long-term storage. The primary water intake of the system is saline water treated with a storage-integrated desalination unit. This water-conscious subsystem for seasonal storage based on green hydrogen is then incorporated into the planning process of a hybrid remote and renewable microgrid. The proposed model uses actual environmental data from Qeshm Island in south Iran as a case study. The simulation results and comparisons with previous research show that the proposed model is effective for managing real-world green hydrogen systems, especially in water-scarce regions. Also, the developed model is versatile enough to be used within any other energy system based on green hydrogen. [ABSTRACT FROM AUTHOR]

Irrigated agriculture is the dominant user of water globally, but most water withdrawals are not monitored or reported. As a result, it is largely unknown when, where, and how much water is used for irrigation. Here, we evaluated the ability of remotely sensed evapotranspiration (ET) data, integrated with other datasets, to calculate irrigation water withdrawals and applications in an intensively irrigated portion of the United States. We compared irrigation calculations based on an ensemble of satellite-driven ET models from OpenET with reported groundwater withdrawals from hundreds of farmer irrigation application records and a statewide flowmeter database at three spatial scales (field, water right group, and management area). At the field scale, we found that ET-based calculations of irrigation agreed best with reported irrigation when the OpenET ensemble mean was aggregated to the growing season timescale (bias = 1.6–4.9 %, R2 = 0.53–0.74), and agreement between calculated and reported irrigation was better for multi-year averages than for individual years. At the water right group scale, linking pumping wells to specific irrigated fields was the primary source of uncertainty. At the management area scale, calculated irrigation exhibited similar temporal patterns as flowmeter data but tended to be positively biased with more interannual variability. Disagreement between calculated and reported irrigation was strongly correlated with annual precipitation, and calculated and reported irrigation agreed more closely after statistically adjusting for annual precipitation. The selection of an ET model was also an important consideration, as variability across ET models was larger than the potential impacts of conservation measures employed in the region. From these results, we suggest key practices for working with ET-based irrigation data that include accurately accounting for changes in soil moisture, deep percolation, and runoff; careful verification of irrigated area and well-field linkages; and conducting application-specific evaluations of uncertainty. [Display omitted] • Compared ET-based irrigation volumes to reported water use data at multiple scales. • ET-based irrigation volumes and reports agreed best at field scale. • Uncertainties include water balance closure and linking irrigated area to wells. • Variation among ET models is substantial relative to irrigation management actions. • ET-based irrigation tracking is promising but application-relevant uncertainties exist. [ABSTRACT FROM AUTHOR]

The Crop-Hydrological-Agent Modeling Platform (PyCHAMP) is a Python-based open-source package designed for modeling agro-hydrological systems. The modular design, incorporating aquifer, crop field, groundwater well, finance, and behavior components, enables users to simulate and analyze the interactions between human and natural systems, considering both environmental and socio-economic factors. This study demonstrates PyCHAMP's capabilities by simulating the dynamics in the Sheridan 6 Local Enhanced Management Area, a groundwater conservation program in the High Plains Aquifer in Kansas. We highlight how a model, empowered by PyCHAMP, accurately captures human-water dynamics, including groundwater level, water withdrawal, and the fraction of cropland dedicated to each crop. We also show how farmer behavior, and its representation, drives system outcomes more strongly than environmental conditions. The results indicate PyCHAMP's potential as a useful tool for human-water research and sustainable groundwater management, offering prospects for future integration with detailed sub-models and systematic evaluation of model structural uncertainty. • PyCHAMP advances human-natural system modeling in agricultural landscapes. • PyCHAMP has expandable aquifer, field, well, finance, and behavior modules. • A case study application demonstrates capabilities for integrating human-water dynamics. [ABSTRACT FROM AUTHOR]

The efficient use of water must be enhanced and promoted to achieve the Sustainable Development Goal (SDG) 6. Thus, to contribute to the achievement of SDG Target 6.4 and close a research gap in SDGs' progress, this paper carries out a water usage efficiency analysis of 126 countries leveraging the AQUASTAT database maintained by the Food and Agriculture Organization of the United Nations (FAO), providing information that can help assess and promote the sustainable use and management of water. The methodology uses a conceptual model that considers a Water Withdrawal (WW) stage and a Water Productivity (WP) stage, each one with its own set of variables, designing a customised non-parametric frontier analysis solution that identifies the countries with the best practices and uses them as benchmarks for global efficient water usage. In particular, the proposed approach uses a non-radial Directional Distance Function (DDF) that estimates the inefficiency along the different dimensions, both desirable and undesirable, quantifying potential improvement and computing an efficiency score for each stage and for the whole system. Due to the heterogeneity of the sample, a metafrontier analysis has been carried out. The results indicate that there are significant differences between countries and regions in terms of water usage efficiency. The regions with highest efficiency include Australia, Western and Central Europe and Southern and Eastern Asia, while Central Asia has the lowest. Most of the inefficiency corresponds to the Gross Value Added dimension and the WW stage efficiency is generally higher than that of the WP stage. • The study has been framed within Design Science Research Methodology (DSRM). • The conceptual model considers two stages: Water Withdrawal and Water Productivity. • A customised, non-parametric metafrontier analysis solution has been designed. • This tool can help develop capacity development programmes at the country level. • This approach can help formulate evidence-based efficient water usage policies. [ABSTRACT FROM AUTHOR]

Carbon capture, utilization and storage (CCUS), a water resource-intensive technology, has been projected to be restricted by water resources in the future. However, the water-saving effects resulting from technology progress and CO 2 -Enhanced water recovery (CO 2 -EWR) process are not been fully considered. Based on the learning curve theory, this study proposes a new water accounting system for CCUS retrofitting of coal-fired power plants (CFPPs) from a dynamic perspective considering power generation, carbon capture, and CO 2 -EWR technology. The results show that the total water withdrawal per unit of CCUS retrofitting with the first-generation capture technology will decrease by 66.89 %, and the total water consumption per unit of that will decrease by 74.70 % from 2021 to 2050. By contrast, the water withdrawal and consumption per unit with the second-generation capture technology will decrease by 74.12 % and 82.51 %, with the overall unit water consumption below 0.5 m3/MWh. Moreover, the water usage caused by CCUS retrofitting will be greatly relieved through the progress of geological sequestration technology (especially the CO 2 -EWR). In addition, the water usage during the capture process for circulation cooling and air-cooling would present an "inverted U" shaped trend affected by the capture scale and technology progress. Remarkably, the water withdrawal and consumption intensity of CFPPs with air-cooling technology is significantly lower than those of the circulation cooling technology for power generation, while the opposite happens if the capture technology is applied. Even so, CCUS retrofitting for the CFPPs with air-cooling technology can save 60 × 104 m3 of water resource after 2040, which is positive for the CCUS deployment in the arid areas of China. [Display omitted] [ABSTRACT FROM AUTHOR]

The article discusses various topics in the field of science. It highlights the potential of geotourism in India and the need for infrastructure and protection of geological monuments. The article also examines how the Indian print media portrays mental illness and the interplay of genetic and epigenetic factors. It suggests that journalists covering mental health should read the research article to improve the quality of their news reports. Additionally, the article addresses groundwater pollution in a village in Karnataka and proposes a more sustainable solution through water harvesting and the use of surface water. Lastly, it discusses the design of artificial reefs in coral lagoons and provides valuable information for conservationists, marine biologists, and fishers. [Extracted from the article]

Lakes are indispensable to ecological balance, supporting biodiversity and human welfare. Despite their importance, lakes around the globe are diminishing at an alarming rate, presenting substantial environmental challenges exacerbated by climate variability and human-induced pressures, such as unsustainable land management and excessive water withdrawals. This study offers an extensive analysis of the desiccation phenomena affecting major lakes on the Iranian plateau, dissecting the complex interplay of contributing factors. We examine meteorological, hydrological, and agricultural drought conditions using indices like SPI, SDI, and SPEI to gain nuanced insights into drought dynamics. This study sheds light on the factors that contribute to the drying up of lakes and quantifies the impact of anthropogenic and climatic drivers on this phenomenon. The findings indicate that the area of all lakes has declined dramatically after the change point, ranging from 51% in the Urmia Lake to an impressive rate (i.e. 100%) in Southern Hamun. Despite the stable rate of meteorological droughts (increasing in temperature by about 1 °C since the 90s and stable precipitation patterns across most basins), the research highlights the ongoing struggle against severe hydrological and agricultural drought conditions. The study delineates the predominant role of anthropogenic activities in the diminishing lake inflows and the consequential drying of the lake, accounting for approximately 100 % in five of the seven lakes. [Display omitted] • A comprehensive examination of desiccation in major lakes across the Iranian plateau. • Anthropogenic drivers are the primary drivers of decreased lake inflows and desiccation. • Assess meteorological, hydrological, and agricultural drought conditions. [ABSTRACT FROM AUTHOR]

• We present a diagnostic approach to model development in human impacted watersheds. • We identify processes needed to model streamflow patterns at different time scales. • We demonstrate this approach by modeling the East Fork watershed (CA, USA). • We apply the model to test hypotheses of hydrological change. • In the East Fork, we identify processes needed to represent streamflow patterns. Most watersheds have human impacts that modify hydrological responses differently over a range of timescales. However, these impacts are not accounted for in most hydrological models. Human impacts in watersheds are diverse and case specific, unlike natural hydrologic processes. Incorporating all plausible human impacts comes at a high data acquisition and modeling cost. This raises the question, which human impacts do we need to incorporate to represent observed streamflow patterns at different timescales? To answer this question, we develop a diagnostic approach to modeling watersheds with human interference. This mixed methods approach is informed by the case history and builds on the top-down hydrological modeling approach where process complexity is incrementally added with changing timescales to identify and respond to changing dominant hydrological processes in a given watershed. Here we implement this modeling approach in the East Fork watershed in California, USA for which data on changes in water imports, withdrawals, irrigation and agriculture land cover is available from the early 1940′s, making it an ideal demonstration case. In the East Fork watershed, we find that incorporation of water imports and rights are sufficient to replicate annual patterns of runoff variability, and that adding crop water demand and irrigation enables replication of monthly and daily patterns, while incorporation of groundwater pumping results in negligible improvements. To demonstrate the capabilities of the diagnostic approach in and beyond this case we conducted two computational experiments: checking for needed model structural change and exploring a counterfactual scenario of intensified agriculture. [ABSTRACT FROM AUTHOR]

We provide a new generalized framework accounting for the effects of water and nutrient uptake by roots in the weathering zone on broad patterns of solute concentration - discharge relationships in rivers. As plants withdraw water from the subsurface, they decrease the area-normalized fluid drainage rate. This results in a discharge flux to springs and streams which is a function of water use by plants, leading to ecosystem regulation of the characteristic timescales of chemical weathering reactions and fluid flow rate. Our predictive framework quantifies the pore water and river solute chemistry generated from water-rock interactions, regulated by the effects of vegetation on water flow rates. To this we add the capacity for vegetation to enrich, passively admit, or discriminate against a given dissolved solute based on ecophysiological needs, thus further modifying the local concentration of a given chemical species in solution across a weathering profile. This uptake flux is not lost to the atmosphere in the same manner as water is removed from the subsurface via evapotranspiration. Rather, these extracted chemical species become incorporated into the topsoil as litter which may be partially or fully resolubilized, creating an upper boundary condition which depends on the uptake and recycling characteristics of the ecosystem. These processes are united through a new solution to the advection-reaction equation which allows vegetation to regulate broad patterns of stream concentration - discharge relationships. We show that ecosystems are capable of both accelerating and impeding water-rock reaction rates across the weathering profile, ultimately leading to both thermodynamic and ecological controls on the baseflow concentration of rock-derived solutes in rivers. • We offer a new predictive model for the water and nutrient demands of ecosystems. • Plants to both enhance and impede mineral weathering reactions. • Plants modulate the relationship between river chemistry and flow rate. • River chemistry reflects both thermodynamic and ecological controls. [ABSTRACT FROM AUTHOR]

Water loss control programs provide several important benefits to utilities. These programs help manage water resources by limiting unnecessary withdrawals, optimize revenue recovery and promote equity among ratepayers, minimize disruptions in the distribution system, optimize supply efficiency, and generate reliable performance data. They also contribute to system integrity by reducing the potential for contamination. Implementing water audits and loss control techniques can lead to financial improvements, savings in water purchase and operating costs, reduced leakage volumes, improved accuracy and integrity of water system input volumes and customer consumption, better water resources management, and the ability to stretch existing supplies to meet increasing needs. Additionally, the auditing process allows utilities to become familiar with their systems and respond quickly to emergencies, while also identifying gaps in billing operations. [Extracted from the article]

The article highlights the successful restoration of the Colorado River Delta in northwestern Mexico, driven by a decade-old water management agreement between the U.S. and Mexico. Topics discussed include the rebound of native bird and plant populations, the impact of conservation efforts by local communities and organizations, and the continuing collaboration between the two countries to maintain water flow and ecosystem health.

• The basin-scale hydrological model was developed for the endorheic lake basin. • The framework deepens understanding of basin water balance components. • The long-term desiccation of the Aral Sea was reproduced from 1961 to 2010. • Historical various water consumptions were quantified as human impact. • The model is physical, which can consider climate change and irrigation scenarios. The desiccation of the Aral Sea, a once vast endorheic lake, serves as a stark reminder of the consequences of unsustainable human water management. This study develops a modeling framework approach to quantify the impact of human activities on endorheic lake water balance. The model integrates a land surface model with an endorheic lake budget model based on basin water balance principles to reproduce past changes in the Aral Sea. We consider key human activities such as agricultural water supply, irrigation efficiency, inflow to terminal lakes, and external water withdrawals as main components impacting the lake. Our results reveal that increased water withdrawals for irrigation, particularly due to inefficient conveyance systems, are the primary drivers of the lake's shrinkage. Specifically, total water consumption for irrigation in the Aral Sea Basin increased from 56.7 Gt/yr in the 1960 s to 81.1 Gt/yr in the 2000 s, with irrigation inefficiency contributing to 30 % of this usage. From 2001 to 2010, water requirements for irrigation, losses due to conveyance inefficiencies, withdrawals to the Karakum Canal, and drainage to Lake Sarygamysh were calculated at 39.0 Gt/yr, 26.3 Gt/yr, 9.4 Gt/yr, and 6.5 Gt/yr, respectively. These various water usages significantly influence the equilibrium states of the endorheic lake. Our integrated physical model effectively demonstrates the balance shift between inflow and evaporation from the lake surface. By considering the impacts of human activities and climate change on watershed terrestrial water circulation, our model offers valuable insights into the causes of change and can help predict future projections and hypothetical scenarios. This research provides a valuable tool for understanding and predicting the fate of similar water bodies facing growing human activities pressures. [ABSTRACT FROM AUTHOR]

Machine learning (ML) models are increasingly popular in environmental and hydrologic modeling, but they typically contain uncertainties resulting from noisy data (erroneous or outlier data). This paper presents a novel probabilistic approach that combines ML and Markov Chain Monte Carlo simulation to (1) detect and underweight likely noisy data, (2) develop an approach capable of detecting noisy data during model deployment, and (3) interpret the reasons why a data point is deemed noisy to help heuristically distinguish between outliers and erroneous data. The new algorithm recognizes that there is no unique way to split the training data into noisy and clean data, and thus produces an ensemble of plausible splits. The algorithm successfully detected noisy data in synthetic benchmark problems with varying complexity and a real-world public supply water withdrawal dataset. The algorithm is generic and flexible, making it suitable for application across a broad range of hydrologic and environmental disciplines. • The study presents a new probabilistic method to identify and reduce the impact of noisy data in machine learning datasets. • The approach generates a supervised noise detection model to identify noisy data during both model development and deployment. • The supervised noise detection model is interpreted to identify factors causing data to appear as noisy. • Interpretation of the supervised noise detection model is used to heuristically distinguish between erroneous and outlier data. [ABSTRACT FROM AUTHOR]

Transboundary lakes are shared by multiple administrative regions. The key to balance the development and protection of transboundary lakes is to properly measure the value of water resources. Most of previous studies on the measurement of lake water resources value have not fully considered the ecosystem service function. This paper proposes a new concept "composite water value" to measure the value of transboundary lakes by integrating the external runoff value and the internal runoff value of water resources. The study constructs a composite water value measurement system for transboundary lakes, further analyzes its influencing factors,and applies the system to the case of Nansi Lake, a representative transboundary lake in eastern China. The results show that: (1) The composite water value of lakes is influenced by various factors, including industrial structure, water withdrawal, and water use methods, which impact the external runoff water value; meanwhile, the composite water quality and fluctuations in lake level are closely associated with the internal runoff water value. From 2008 to 2021, the average annual composite water value of Nansi Lake was 39.628 billion yuan, exhibiting a "rising-falling-fluctuating rising" trend due to pollution control policies, reduced precipitation, and enhanced water-saving technologies successively. (2) From a long-term perspective, it is necessary to focus on the internal runoff water use value of lakes. The internal runoff water value of Nansi Lake has been over 75% of the composite water value, and flood storage and water conservation are important manifestations of its ecosystem service value. (3) The external runoff water value of lake is closely related to the internal runoff water value, and relevant departments need to consider the balance between the water withdrawal of multiple cities along the lake and the retained water volume of the lake to achieve the maximum benefit of composite water value. [Display omitted] • Lake water value includes multiple values derived from external runoff water out of lakes and internal runoff water in lakes. • The ecosystem service value of internal runoff water is much higher than the economic value of external runoff water. • There is a tradeoff relationship between the internal runoff water and external runoff water. • Composite water value measurement can help balance transboundary lakes development and protection. [ABSTRACT FROM AUTHOR]

Population and water withdrawal data sets are currently faced with difficulties in collecting, processing and verifying multi-source time series, and the spatial distribution characteristics of long series are also relatively lacking. Time series is the basic guarantee for the accuracy of data sets, and the production of long series spatial distribution is a realistic requirement to expand the application scope of data sets. Through the time-consuming and laborious basic processing work, this research focuses on the population and water intake time series, and interpolates and extends them to specific land uses to ensure the accuracy of the time series and the demand of spatially distributed data sets. This research provides a set of population density and water intensity products from 1960 to 2020 distributed to the administrative units or the corresponding regions. The data set fills the gaps in the multi-year data set for the accuracy of population density and the intensity of water withdrawal. Measurement(s) distributed global population and water withdrawal Technology Type(s) mathematical statistics and analysis [ABSTRACT FROM AUTHOR]

A proper management of fresh groundwater lenses in small islands is required in order to avoid or at least limit uncontrolled saltwater intrusion and guarantee the availability of the resource even during drought occurrences. An accurate estimation of the freshwater volume stored in the subsoil is a key step in the water management decision process. This study focused on understanding the hydrogeological system behaviour and on assessing the sustainable use of the groundwater resource in Nauru Atoll Island (Pacific Ocean). A first phase, concerning the hydrogeological characterization of the island, highlighted the occurrence of few drought-resilient freshwater lenses along the seashore. The second part of the study focused on the characterization of a freshwater lens found in the northern coastal area and identified such area as the most suitable for the development of groundwater infrastructures for water withdrawal. The characterization activities allowed quantifying the freshwater lens thickness and volume in order to assess the capability to satisfy the population water demand. A geo-electrical tomography survey was carried out, and a 3D density-dependent numerical model was implemented in SEAWAT. The model results demonstrated that in small islands freshwater can unexpectedly accumulate underground right along the seashore and not in the centre of the island as is commonly believed. Furthermore, the model can constitute a useful tool to manage the groundwater resources and would allow the design of sustainable groundwater exploitation systems, avoiding saltwater intrusion worsening. [ABSTRACT FROM AUTHOR]

Background: Aggregations of cyanobacteria in lakes and reservoirs are commonly associated with surface blooms, but may also occur in the metalimnion as subsurface or deep chlorophyll maxima. Metalimnetic cyanobacteria blooms are of great concern when potentially toxic species, such as Planktothrix rubescens, are involved. Metalimnetic blooms of P. rubescens have apparently increased in frequency and severity in recent years, so there is a strong need to identify reservoir management options to control it. We hypothesized that P. rubescens blooms in reservoirs can be suppressed using selective withdrawal to maximize its export from the reservoir. We also expect that altering the light climate can affect the dynamics of this species. We tested our hypothesis in Rappbode Reservoir (the largest drinking water reservoir in Germany) by establishing a series of withdrawal and light scenarios based on a calibrated water quality model (CE-QUAL-W2). Results: The novel withdrawal strategy, in which water is withdrawn from a certain depth below the surface within the metalimnion instead of at a fixed elevation relative to the dam wall, significantly reduced P. rubescens biomass in the reservoir. According to the simulation results, we defined an optimal withdrawal volume to control P. rubescens blooms in the reservoir as approximately 10 million m3 (10% of the reservoir volume) during its bloom phase. The results also illustrated that P. rubescens growth can be most effectively suppressed if the metalimnetic withdrawal is applied in the early stage of its rapid growth, i.e., before the bloom occurs. In addition, our study showed that P. rubescens biomass gradually decreased with increasing light extinction and nearly disappeared when the extinction coefficient exceeded 0.55 m−1. Conclusions: Our study indicates the rise in P. rubescens biomass can be effectively offset by selective withdrawal as well as by reducing light intensity beneath the water surface. Considering the widespread occurrence of P. rubescens in stratified lakes and reservoirs worldwide, we believe the results will be helpful for scientists and managers working on other water bodies to minimize the negative impacts of this harmful cyanobacteria. Our model may serve as a transferable tool to explore local dynamics in other standing waters. [ABSTRACT FROM AUTHOR]

The aim of the work is to develop a mechanism for cross-border carbon regulation for countries importing products to the EU, which will equally allow importing countries to fulfill the conditions of the Carbon Border Adjustment Mechanism (CBAM), encourage manufacturers to reduce CO2 emissions, and also provide importing countries with opportunities to replenish their budget by introducing paid emission quotas greenhouse gases. The work makes a significant contribution to stimulating the reduction of CO2 emissions by producers due to the proposed tax mechanism and preventing the leakage of greenhouse gases on the territory of third countries according to the CBAM policy. The EU evaluates double taxation, so if a carbon tax has been withdrawn in the territory of the exporting country, then such a tax will not be levied again in the EU. All this involves stimulating exporting countries by creating their own taxation systems, which will have international qualifications and be recognized by countries around the world. When choosing a taxation mechanism, it is important to choose the specifics for visiting group gases. The study was conducted on the basis of methods of comparison, modeling, analysis and deduction. [ABSTRACT FROM AUTHOR]

In this paper, a comprehensive semi-distributed water balance model is presented for basins under anthropogenic impacts. It benefits from data in different time resolutions for estimation of surface and groundwater exchanges and water withdrawals for various purposes. Ground-based data such as vegetation cover and topography have been used to determine the model parameters. The performance of the proposed model was tested for 38 sub-basins in Iran representing various climate conditions, vegetation covers, and agricultural practices. The results demonstrated a good performance in terms of estimating streamflows at the basin outlet, with more than 90% of sub-basins having a correlation coefficient above 0.9. However, the model showed a relatively weaker performance in the estimation of annual aquifer storage volume change. Correlation coefficients above 0.6 were calculated for more than half of the aquifers in the study area. [ABSTRACT FROM AUTHOR]

One of the suggested mechanisms behind the success of non‐native plants in recipient ecosystems is competition avoidance with natives by means of different resource‐use strategies, such as deeper water uptake under dry conditions.We aimed at evaluating water source partitioning between native and non‐native tree species coexisting in central Spain floodplains; determining the dependency on drought stress of such water sources use; and assessing if the reliance on deeper water sources relates with physiological and growth performance.We assessed water uptake depth, leaf functional traits related to physiological performance and growth of native (Populus alba) and non‐native trees (Ailanthus altissima, Robinia pseudoacacia) coexisting in riparian forests under different drought conditions (drier, intermediate and wetter). We analysed δ2H and δ18O isotopes in xylem water and in soil water from top, mid and deep soil depths and determined the contribution of each water source to overall plant xylem water. Leaf traits related with resource use and secondary growth were assessed for each species.We found stronger differences between sites than between species, with all species taking more deep water in the driest site (~45% of the xylem water) than in the wettest (~15%). However, under drier conditions, species differences were significant for top‐soil water use, with R. pseudocacia withdrawing more superficial water (~22%) than A. altissima (~8%). These results indicate stronger water partitioning under drier conditions. Non‐native species showed a physiological strategy characterized by greater leaf N, water content, and enriched δ13C and δ15N values independently of the deep‐water uptake. However, a positive relationship between deep soil water use and such strategy was found for P. alba.We highlight that those native and non‐native species differences were more evident regarding physiological performance at leaf level than for deep‐water uptake or growth. Furthermore, our results suggest that differences in water sources used by coexisting species may increase under drier conditions. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Clarifying the response of the terrestrial water cycle to the influence of climate change and human activities and accurately grasping the variations in the water cycle and water resources under the changing environment are the scientific basis for achieving the sustainable development of the Yangtze River Economic Belt. In this paper, a dataset of rasterized water consumption in the Yangtze River Basin was constructed, and an artificial water withdrawal module considering the process of water intake, water consumption and drainage was designed, which was coupled with the land surface model CLM4.5. Based on the multi-scale validation in the Yangtze River Basin, two numerical simulation experiments were carried out to reveal the impact of artificial water withdrawal on the water cycle process in the Yangtze River Basin. The results indicate that artificial water withdrawal leads to an 0.1–0.3 m increase in groundwater table depth in most areas of the basin, and agricultural irrigation leads to a 0–0.03 mm3/mm3 increase in soil moisture in most areas. Climate change dominates the variation of discharge in the Yangtze River basin and leads to an increase in discharge at most stations. [ABSTRACT FROM AUTHOR]

The water governance discourse focuses on the use of water from rivers—and increasingly lakes and aquifers—for a variety of human uses, often in a competing manner. Largely missing from this discourse are wetlands. Despite an increased understanding of the benefits of wetlands, global wetland area continues to decrease. Particularly in international river basins, upstream water withdrawals are having negative impacts on wetlands, and the communities that rely on them downstream. Following the framework of transboundary water cooperation, the joint management of transboundary wetlands in the context of integrated basin management may prevent conflict and lead to further collaboration. As a first step to understand how wetlands may fit into water cooperation, this research employs spatial analysis and document analysis to identify transboundary wetlands and possible institutions to manage them, providing a basis for analyzing conflict and cooperation dynamics in them. The products of this research are a database and map of 300 transboundary wetlands, including the river basins (and, when applicable, the River Basin Organizations) they fall within. [ABSTRACT FROM AUTHOR]

This paper investigates the use of high resolution (~100 m) surface soil moisture (SSM) maps to detect irrigation occurrences, in time and space. The SSM maps have been derived from time series of Copernicus Sentinel-1 (S-1) and Sentinel-2 (S-2) observations. The analysis focused on the Riaza irrigation district in the Castilla y León region (Spain), where detailed information on land use, irrigation scheduling, water withdrawal, meteorology and parcel borders is available from 2017 to 2021. The well-documented data basis has supported a solid characterization of the sources of uncertainties affecting the use of SSM to map and monitor irrigation events. The main factors affecting the irrigation detection are meteo-climatic condition, crop type, water supply and spatial and temporal resolution of Earth observation data. Results indicate that approximately three-quarters of the fields irrigated within three days of the S-1 acquisition can be detected. The specific contribution of SSM to irrigation monitoring consists of (i) an early detection, well before vegetation indexes can even detect the presence of a crop, and (ii) the identification of the irrigation event in time, which remains unfeasible for vegetation indexes. Therefore, SSM can integrate vegetation indexes to resolve the irrigation occurrences in time and space. [ABSTRACT FROM AUTHOR]

The article focuses on the history of researching the hydrometeorological regime in the Danube mouth area. In the middle of the XIX century, the start of the investigations was related to the necessity of improving navigation conditions in the area. In the post-war years, hydrological works in the delta and the nearshore zone of the Danube mouth were conducted by hydrologists from the USSR and Romania within an agreed program, using common methodologies and instruments of measurement. The main goal of systematic hydrological research carried out by the Danube Hydrometeorological Observatory in 1958–1990 was to assess changes in the hydrological regime of the Danube mouth area under the influence of implemented and planned water management activities, such as dredging, channel straightening, construction of protective dikes and irretrievable water runoff withdrawal. In 1991–2021, the cooperation between Ukrainian and Russian hydrologists resulted in a joint monograph published in 2004 (it paid much attention to researching the impact of modern climate changes on the hydrological conditions in the basin and delta of the Danube River). In the last 30 years, a pressing political, socio-economic and environmental challenge in the Danube region has been to restore the national navigation canal Danube–Black Sea through the Ukrainian part of the delta. The prospects of further development of hydrological investigations in the Danube mouth area under global climate change consist in modernizing the system of hydrological and morphological monitoring by means of material and technical re-equipment of the Hydrometeorological Service of Ukraine, implementing basin principles of water resources management, along with strengthening international cooperation. [ABSTRACT FROM AUTHOR]

In this article, we present the use of the coupled land surface model and groundwater flow model SWAT-MODFLOW with the decision support tool WEAP (Water Evaluation and Planning software) to predict future surface-water abstraction scenarios in a complex river basin under conditions of climate change. The modelling framework is applied to the Dee River catchment in Wales, United Kingdom. Regarding hydrology, the coupled model improves overall water balance and low-streamflow conditions compared with a stand-alone SWAT model. The calibrated SWAT-MODFLOW is employed with high-resolution climate model data from the UKCP18 project with the future scenario of RCP85 from 2020 to 2040. Then, water supply results from SWAT-MODFLOW are fed into WEAP as input for the river reach in the downstream region of the river basin. This system is utilized to create various future scenarios of the surface-water abstraction of public water supply in the downstream region—maximum licensed withdraw, 50% authorized abstractions, monthly time series with 1% increases in water use, and maximum water withdraw per year based on historical records repeated every year with 1% increases in water use—to estimate the unmet demands and streamflow requirement. This modelling approach can be used in other river basins to manage scenarios of supply and demand. [ABSTRACT FROM AUTHOR]

This paper presents a low-cost and scalable method for providing a sustainable water allocation for enterprises based on the hydrological, economic, and demographic contexts of their facilities. Context-based performance indicators are vital for effectively monitoring and achieving the Sustainable Development Goals (SDGs). Currently, the SDGs consist of 17 goals that are associated with 169 targets and 232 indicators. Making valid and objective measurements of the 232 indicators represents a significant challenge for scientists and policy makers. Achieving the SDGs will likely involve significant efforts in developing and sustaining systems for monitoring status and progress, providing incentives, and conducting enforcement. Provision of low-cost Sustainable Development Performance Indicators (SDPIs) of progress at high spatial and temporal resolution is essential for effective management by governments and businesses. The water allocations we produce are based on a facility's total and consumptive use of water, their contribution to gross domestic product (GDP), their number of full-time employees, the population and GDP of several geographic contexts, and the annually specific hydrological balance (i.e., precipitation minus evapotranspiration) of those contexts. The allocations and related sustainability assessments are determined for a range of geographic contexts (circular regions centered on the facility with radii of 10, 50, 100, 200, and 300 km respectively). From the hydrological data we give priority to 'Water for Nature' and allocate a proportion of the remaining 'Water for Economy' to the facility based on their contribution to GDP and the number of full-time employees they have. This allocation is compared to their actual water withdrawals to provide an indication of the sustainability of their economic activity. [ABSTRACT FROM AUTHOR]

Forests are among the most important renewable natural resources. While having a great range of benefits, the crucial advantage of forests is the production of oxygen and the absorption of pollutants. Thus, the current article attempts to examine forest exploitation as a source of wood to prevent forest overexploitation. Three smugglers, residents, and timber companies exploit this resource. There is a competition for the perception of this common source between these factors. In this article, these interactions are considered a game in order to obtain the most probable solution in the real competition between these factors by examining this game. This answer is the balance of the game. In order to use this answer, the behavior of the players can be predicted and used in management planning. Since the amount of withdrawals of operating companies depends on the current inventory (t), the player's behavior is determined by the system's current state and then Markov equilibrium was obtained for them. [ABSTRACT FROM AUTHOR]

The pressure on freshwater resources is leading to diminishing flows in some of the critical river systems across the globe. India is no exception, and this is mainly because of water withdrawal for irrigation, which is often to the tune of 70% to 80% of the lean season flows, with some proportion for domestic and industrial use. While graduating from the concept of environmental flows and its assessment methodologies in India, the water-managers, the researchers and the conservationists are now moving towards answering the next question, if the rivers are to be revived, where will the water come from, especially in the case of over-allocated rivers, including the River Ganga. While the logical way is to look at the biggest user of water, i.e., irrigation, it remains to be seen whether the irrigation water savings will actually lead to enhancing flows in a river, complementing the efforts towards maintaining e-flows in rivers, or whether it will lead to more area under agriculture, bring changes in cropping patterns towards more water-intensive crops or result in something else. This is a growing debate across the globe, where India is no exception, and there has been a wide range of opinions in this regard. This paper discusses the process, findings and lessons from a joint initiative involving farmers, the Uttar Pradesh state Irrigation and Water Resources Department, Bijnor District Administration and a conservation organisation, WWF, to enhance flows in a sub-tributary, called the Karula River, which is part of the Ganga River system. Another objective of this paper is to look at the scalability and replicability of similar approaches in other irrigation command areas to benefit nearby river systems in general. Under this initiative, the team attempted to enhance flows in the river Karula by routing the saved water from irrigation supplies in a canal commanded area. This saving of water is being achieved due to supply-side and demand-side measures that are being adopted in the project area. With the objective of ensuring the sustainability of the initiative, efforts are made to form an institutional arrangement, through which this initiative can be sustained beyond the project support. [ABSTRACT FROM AUTHOR]

Measurements of the source levels of 9880 passes of 3188 different large commercial ships from the Enhancing Cetacean Habitat and Observation (ECHO) program database were used to investigate the dependencies of vessel underwater noise emissions on several vessel design parameters and operating conditions. Trends in the dataset were analyzed using functional regression analysis, which is an extension of standard regression analysis and represents a response variable (decidecade band source level) as a continuous function of a predictor variable (frequency). The statistical model was applied to source level data for six vessel categories: cruise ships, container ships, bulk carriers, tankers, tugs, and vehicle carriers. Depending on the frequency band and category, the functional regression model explained approximately 25%–50% of the variance in the ECHO dataset. The two main operational parameters, speed through water and actual draft, were the predictors most strongly correlated with source levels in all of the vessel categories. Vessel size (represented via length overall) was the design parameter with the strongest correlation to underwater radiated noise for three categories of vessels (bulkers, containers, and tankers). Other design parameters that were investigated (engine revolutions per minute, engine power, design speed, and vessel age) had weaker but nonetheless significant correlations with source levels. [ABSTRACT FROM AUTHOR]

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Flap-type wave energy converters (OWSCs) are used near the coast to generate electricity and pump water. The draft depth and incident wave frequency are parameters affecting the performance of this type of converter. In this paper, the effect of water draft depth and incident wave frequency on the performance of a converter at a scale of 1: 8 has been investigated experimentally. The power take-off system (PTO) is hydraulic. The Caspian Sea was also selected as the target sea. After calibration of equipment and uncertainty analysis, experimental tests were performed in the wave flume of Babol Noshirvani University of Technology by considering regular waves. Considering the predominant period of the waves of the Caspian Sea ([4-8] seconds), after Froud scaling, the tests were performed in the period interval of [1.6-2.5] seconds, which is equivalent to the frequency interval [0.4-0.63 ] Hz. Also, due to the importance of the converter's draft depth, the converter's performance was evaluated from the draft depth of -0.1 (submerged flap) to 0.6 m. According to the results, the best converter performance was at the lowest frequency; the converter performance decreased with increasing frequency. The best converter performance was obtained at the dimensionless draft depth of 0.43 (equivalent to 0.4 m draft depth), and the converter power was reduced at larger and smaller draft depths. It is worth noting that at a negative draft depth (submerged flap), the converter has the lowest performance. The maximum values of flow, power, and pressure on a laboratory scale were 0.14 liters per second, 21.3 watts, and 156.8 kPa, respectively, which were measured at 18 liters per second, 22.66 kW, respectively, using Froud scaling method and will be 1249/61 kPa. [ABSTRACT FROM AUTHOR]

Reports of the Intergovernmental Panel on Climate Change (IPCC) indicate that temperature rise is still the general trend of the global climate in the 21st century. Invasive species may benefit from the increase in temperature, as climate can be viewed as a resource, and the increase in the available resources favors the invasibility of invasive species. This study aimed to assess the overwintering growth of the cosmopolitan invasive plant water hyacinth (Eichhornia crassipes) at its northern boundary. Using E. crassipes as a model plant, a cross‐year mesocosm experiment was conducted to determine 17 plant functional traits, including growth, morphological, root topological, photosynthetic, and stoichiometric traits, under climate warming (ambient, temperature rises of 1.5°C and 3.0°C), and water drawdown or water withdrawal (water depths of 1, 10, and 20 cm) treatments. The overwintering growth of E. crassipes was facilitated by climate warming and proper water drawdown, and climate warming played a leading role. A temperature rises of 3.0°C and a water depth of 10 cm were the most suitable conditions for the overwintering and rooting behavior of the plant. Controlling the temperature to within 1.5°C, an ambitious goal for China, still facilitated the overwintering of E. crassipes. With climate warming, the plant can overwinter successfully, which possibly assists it in producing and spreading new ramets in the vernal flood season. The new rooting behavior induced by ambient low temperature may be viewed as a unique growth adaptation strategy for a niche change, as it helps these plants invade empty niches left by dead free‐floating plants on the water surface following winter freezes. With continued global warming, the distribution of the plant may expand northward, and eradication of the plant during the winter water drawdown period may be a more effective strategy. [ABSTRACT FROM AUTHOR]

In the United States, greater attention has been given to developing water supplies and quantifying available waters than determining who uses water, how much they withdraw and consume, and how and where water use occurs. As water supplies are stressed due to an increasingly variable climate, changing land‐use, and growing water needs, greater consideration of the demand side of the water balance equation is essential. Data about the spatial and temporal aspects of water use for different purposes are now critical to long‐term water supply planning and resource management. We detail the current state of water‐use data, the major stakeholders involved in their collection and applications, and the challenges in obtaining high‐quality nationally consistent data applicable to a range of scales and purposes. Opportunities to improve access, use, and sharing of water‐use data are outlined. We cast a vision for a world‐class national water‐use data product that is accessible, timely, and spatially detailed. Our vision will leverage the strengths of existing local, state, and federal agencies to facilitate rapid and informed decision‐making, modeling, and science for water resources. To inform future decision‐making regarding water supplies and uses, we must coordinate efforts to substantially improve our capacity to collect, model, and disseminate water‐use data. Research Impact Statement: To inform future decision‐making regarding water supplies and uses, we must coordinate efforts to substantially improve our capacity to collect, model, and disseminate water‐use data. [ABSTRACT FROM AUTHOR]

On the Arctic Coastal Plain (ACP) in northern Alaska (USA), permafrost and abundant surface‐water storage define watershed hydrological processes. In the last decades, the ACP landscape experienced extreme climate events and increased lake water withdrawal (LWW) for infrastructure construction, primarily ice roads and industrial operations. However, their potential (combined) effects on streamflow are relatively underexplored. Here, we applied the process‐based, spatially distributed hydrological and thermal Water Balance Simulation Model (10 m spatial resolution) to the 30 km2 Crea Creek watershed located on the ACP. The impacts of documented seasonal climate extremes and LWW were evaluated on seasonal runoff (May–August), including minimum 7‐day mean flow (MQ7), the recovery time of MQ7 to pre‐perturbation conditions, and the duration of streamflow conditions that prevents fish passage. Low‐rainfall scenarios (21% of normal, one to three summers in a row) caused a larger reduction in MQ7 (−56% to −69%) than LWW alone (−44% to −58%). Decadal‐long consecutive LWW under average climate conditions resulted in a new equilibrium in low flow and seasonal runoff after 3 years that included a disconnected stream network, a reduced watershed contributing area (54% of total watershed area), and limited fish passage of 20 days (vs. 6 days under control conditions) throughout summer. Our results highlight that, even under current average climatic conditions, LWW is not offset by same‐year snowmelt as currently assumed in land management regulations. Effective land management would therefore benefit from considering the combined impact of climate change and industrial LWWs. Key Points: Winter lake water withdrawal (LWW) reduces summer low‐ and average streamflow with the recovery time of up to 3 yrWinter LWW is not counterbalanced by same‐year snowmelt recharge as currently assumed in land management regulationsLow rainfall (21% of normal) combined with winter LWW lead to intermittently dry streams in the following three summers [ABSTRACT FROM AUTHOR]

This study aimed to analyze the available amount of water in the Dragaçina River to meet the different water needs in the Municipality of Suhareka. The water problems in this city are more pronounced, especially in the vegetation period of July-September, where the area is significantly affected by drought. The Dragacina River carries about 10 hm³ of water per year, and affected neither by urbanism nor massive deforestation of the basin. However, there are no multi-year measurements of inflows for this river, whether they are average, maximum or minimum ones. Therefore, the study is based on several multi-annual monthly rainfall measurements and some characteristics of the Dragaçina River Basin. Knowing the average annual flow coefficient η = Peff / Pbruto it is possible to convert these precipitations to Peff [mm] flow and then to monthly flow. The inputs for other years from 1983/84 onwards are obtained by simulating time series. Then, for such inflows, the probability distribution functions of small waters are assigned and the usable volume balance is carried out. Assuming an average annual withdrawal from the reservoir QAminmes. = 0.63 × Qmes. which should be constant throughout the years, then the length of the critical period will be 0.13 years or approximately 48 days, for PH = 95%. Starting from the initial acquired volume of 1 hm³ it is possible to achieve 95% < PH < 99%. Therefore, it follows from this analysis that this river can provide a significant amount of water for the needs of the Municipality of Suhareka. [ABSTRACT FROM AUTHOR]

Population growth is increasing the pressure on water resource availability. For useful assessment and planning for societal water availability impacts, it is imperative to disentangle the direct influences of human activities in the landscape from external climate‐driven influences on water flows and their variation and change. In this study we used the water balance model, a gridded global hydrological model, to quantify and distinguish human‐driven change components, modified by interventions such as dams, reservoirs, and water withdrawals for irrigation, industry, and households, from climate‐driven change components on four key water balance variables in the terrestrial hydrological system (evapotranspiration, runoff, soil moisture, storage change). We also analyzed emergent effect patterns in and across different parts of the world, facilitating exploration of spatial variability and regional patterns on multiple spatial scales, from pixel to global, including previously uninvestigated parts of the world. Our results show that human activities drive changes in all hydrological variables, with different magnitudes and directions depending on geographical location. The differences between model scenarios with and without human activities were largest in regions with the highest population densities. In such regions, which also have relatively large numbers of dams for irrigation, water largely tends to be removed from storage and go to feed increased runoff and evapotranspiration fluxes. Our analysis considers a more complete set of hydrological variables than previous studies and can guide further research and management planning for future hydrological and water availability trends, including in relatively data‐poor parts of the world. Plain Language Summary: The global population is growing, increasing demands for water use. Knowledge of how human activities affect water resources is available for some areas and water cycle components, but more data are needed for solid scientific understanding of climate and human‐driven effects on water resources in the past and present, and to underpin management approaches to future trends in hydrology and water availability. This study examined human activity effects on different components of the terrestrial water cycle, distinct from the effects of climate change. Results showed that human activities alter movements of water worldwide, with changes, magnitudes, and directions depending on world region. The greatest human‐driven changes emerged in regions with the highest population density, which also have relatively large numbers of dams providing water for agricultural use. Overall, the water changes in these regions tend to include water removal from storage going to feed increased evapotranspiration and/or runoff. Regions with such change trends will require solutions to overcome future negative impacts on society and ecosystems. This study showed how different water cycle components and land regions have been affected by changes in human activities, and findings can guide research and management planning for hydrological and water availability in future years. Key Points: Human activities affected all four hydrological variables studied (runoff, evapotranspiration, soil moisture, and storage change)Human‐driven hydrological effects emerged as considerable over the northern tropical to temperate latitudes, where most people liveHigher runoff was seen in areas with dams of various types, with additional hydrological effects depending on dam type [ABSTRACT FROM AUTHOR]

The valley of Cuatro Ciénegas in Coahuila, Mexico, has the highest degree of local endemism of any habitat in North America. Despite the arid desert climate, the basin harbours an extensive system of permanent streams, wetlands, and spring‐fed pools, and is divided into two sub‐basins by the central Sierra de San Marcos y Pinos.Microsatellite loci were surveyed to infer the genetic diversity and population structure of Gambusia marshi, a poeciliid fish endemic to the Cuatro Ciénegas basin and the Río Salado de Nadadores in north‐east Mexico.Bayesian clustering analysis revealed four genetic populations within G. marshi and a major east–west division corresponding to the Sierra de San Marcos y Pinos.Most sample sites exhibited high levels of genetic differentiation, although there is evidence for recent gene flow between some of these locations. The population of G. marshi in Poza Anteojo is extremely divergent, and appears to represent a remnant of a different historical system. The G. marshi in Poza Anteojo should be considered an independent management unit.Documenting the number and distribution of distinct populations of G. marshi provides additional justification for protecting the Cuatro Ciénegas basin from additional water withdrawals and further homogenization via the construction of additional canals.By analysing the population structure of a widespread species within a region containing many range‐restricted and endemic species, these results shed new light on historical connections among aquatic ecosystems and raise awareness of the possibility that units of conservation concern may exist in other, more range‐restricted taxa in the Cuatro Ciénegas basin and encourage the assessment of their conservation status.The results also have implications for species in arid regions in other parts of the world that may also harbour as yet unrecognized isolated populations worthy of conservation. [ABSTRACT FROM AUTHOR]

Mosses of the genus Sphagnum are the main components of peatlands, a major carbon-storing ecosystem. Changes in precipitation patterns are predicted to affect water relations in this ecosystem, but the effect of desiccation on the physiological and molecular processes in Sphagnum is still largely unexplored. Here we show that different Sphagnum species have differential physiological and molecular responses to desiccation but, surprisingly, this is not directly correlated with their position in relation to the water table. In addition, the expression of drought responsive genes is increased upon water withdrawal in all species. This increase in gene expression is accompanied by an increase in abscisic acid (ABA), supporting a role for ABA during desiccation responses in Sphagnum. Not only do ABA levels increase upon desiccation, but Sphagnum plants pre-treated with ABA display increased tolerance to desiccation, suggesting that ABA levels play a functional role in the response. In addition, many of the ABA signalling components are present in Sphagnum and we demonstrate, by complementation in Physcomitrium patens , that Sphagnum ABI3 is functionally conserved. The data presented here, therefore, support a conserved role for ABA in desiccation responses in Sphagnum. [ABSTRACT FROM AUTHOR]

Cooling towers have such a significant influence on work and efficiency that researchers and designers are working tirelessly to enhance their performance. A prototype design for a natural draft hybrid (wet/dry) cooling tower has been created, relying on geometrical, dynamic, and thermodynamic similarities. Based on Iraqi weather, experiments have been conducted using splash fill (150 mm) in summer (hot and dry) weather conditions. This study investigated heat transfer mechanisms of both air and water in a natural draft hybrid cooling tower model(NDHCTs), both directly (wet section) and indirectly (dry section). The tower is filled with splash-style packing, and the warm water is spread throughout the building using sprayer nozzles. The influences of water flow rates, fill thickness, and air velocity on the cooling range, approach, cooling capacity, thermal efficiency of the cooling tower, water evaporation loss into the air stream and water loss percentage were explored in this study. The experimental were carried out with four different water flow rates, ranging from 7.5 to 12 (Lpm) litres per minute, and eight different air velocities, all while keeping a constant inlet water temperature and a zero (m/s) crosswind. Data has been gathered, and performance variables have been determined. The findings demonstrate that the cooling tower's efficacy increases when the water flow rate is low, and the cooling range increases with increasing air velocity and decreases with increasing water flow rate; for a 7.5 Lpm water flow rate and a 2.4 m/s air velocity, it expanded to 19.5°C. The cooling capacity increased to 23.2 kW for a water flow rate of 12 Lpm and an air velocity of 2.4 m/s. [ABSTRACT FROM AUTHOR]