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Determining situation of groundwater vulnerability plays a crucial role in studying the groundwater resource management. Generally, the preparation of reliable groundwater vulnerability maps provides targeted and practical scientific measures for the protection and management of groundwater resources. In this study, in order to evaluate the groundwater vulnerability of Kerman–Baghin plain aquifer, two developed indicators including composite DRASTIC index (CD) and nitrate vulnerability index (NVI) based on DRASTIC index were considered. Soft computing methods, including Gene Expression Programming (GEP), Evolutionary Polynomial Regression (EPR), Multivariate Adaptive Regression Spline (MARS), and M5 Model Tree (MTM5) have been used to provide formulations for prediction of NVI. Soft computing techniques were fed nine input parameters: depth to water level, net recharge, aquifer environment, soil environment, topography, effect of unsaturated area, hydraulic conductivity, land use, and potential risk related to land use. After calculating the vulnerability by soft computing methods, the results showed that the EPR model with Correlation Coefficient (R) of 0.9999 and Root Mean Square Error (RMSE) = 0.2105 has the best performance in the testing stage in comparison with MARS (R = 0.9966 and RMSE = 2.408), M5MT (R = 0.9956 and RMSE = 2.988), and GEP (R = 0.9920 and RMSE = 3.491). Although the EPR and GEP models have more complex mathematical computations than other soft computing models, the MARS and MT model that have quadratic polynomial and multivariable linear structures respectively, can be considered as the best alternative. According to the MARS model, the vulnerability of the region is divided into two categories: very low vulnerability (73.06%) and low vulnerability (26.94%). Overall, the statistical results of soft computing techniques were indicative of effective formulations for evaluating the DRASTIC index. [ABSTRACT FROM AUTHOR]

Groundwater resource management in drylands, characterized by climate variability and population growth, is difficult. Exploration and exploitation of groundwater, due to inadequate surface water is very costly. This study employed the analytic hierarchy process (AHP) and GIS to identify groundwater potential (GWP) areas in a semi-arid region of Nigeria. Land-use-land-cover, drainage density, slope, rainfall, static water level, soil, lithology, and aquifer were selected for GWP analysis. Parameter weights were determined using AHP and ranked based on their contribution to GWP by experts. The parameters were then integrated using the weighted overlay tool in ArcGIS 10.5 to produce a GWP map of the study area. Borehole yield data from 245 wells were collected to determine the model accuracy and model validation. Results classified the study area into very high GWP (1.9%), high GWP (8.8%), moderate GWP (62%), low GWP (20.70%) and very low GWP (6.6%). Areas with better GWP include Gurun, Dugol, Zago, Kumbo, Dukku, Doguwa, Riruwai, Dambazau, etc. Moderate GWP areas are widely spread across the state while areas with poor GWP include Sharawa, Kadewa, Koya, Dagar, Jigilawa, Galwanga, Yanganau, Kunchi, Tofa, Tsanyawa, etc. Validation of the AHP model with borehole yield data shows a correlation coefficient of 71.3% giving a good prediction. AHP and GIS can be used to successfully map GWP areas which could serve as an exploration guide for sustainable management of groundwater resources in semi-arid areas. [ABSTRACT FROM AUTHOR]

The integration of different sources of geological and hydrogeological information and the application of interdisciplinary methods have informed the origin of the thermal springs of Alhama de Aragón and Jaraba, as well as other associated semi thermal springs (1200 L/s of combined flow, 711 L/s at over 30 °C), which is the main objective of this article. These springs come mainly from the autogenous recharge that occurs in the Cretaceous calcareous outcrops that border the Almazán Basin to the north, both in the Ebro Basin (Jalón Valley) and in the Duero Basin. The aquifer, shaped by upper Cretaceous limestones under the Palaeogene and Neogene rocks of the Almazán Basin, has extensive depths of more than 4000 m in the NE sector. This hydrostratigraphic unit has been affected by a generalized pre-Paleogene karstification that provides the main porosity to the aquifer. The underground flow moves in a NW–SE direction, crossing the Duero–Ebro divide, favoured by the topographic difference in elevation between the two basins. The regional flow is coherent with the progressive increase in temperature, infiltrating recharge water age (about 20–25 years in the semi-thermal springs, and more than 60 years in the Alhama and Jaraba springs), mineralization, and flow of the springs through which the system discharges. This issue is key to being able to design any sustainable conservation strategy in terms of quantity and quality of resources within the recharge area of the most important thermal springs in Spain. The Jaraba and Alhama de Aragón hot springs share the same or similar temperature, chemical composition, and geological contact of the spring. Their tritium isotopic composition and its evolution over time are practically the same. Their isotopic composition in D and 18O is also very similar. Both springs share the same recharge zone of similar altitude and constitute the end of flow tubes of similar length and flow rate. [ABSTRACT FROM AUTHOR]

Abstract Determining situation of groundwater vulnerability plays a crucial role in studying the groundwater resource management. Generally, the preparation of reliable groundwater vulnerability maps provides targeted and practical scientific measures for the protection and management of groundwater resources. In this study, in order to evaluate the groundwater vulnerability of Kerman–Baghin plain aquifer, two developed indicators including composite DRASTIC index (CD) and nitrate vulnerability index (NVI) based on DRASTIC index were considered. Soft computing methods, including Gene Expression Programming (GEP), Evolutionary Polynomial Regression (EPR), Multivariate Adaptive Regression Spline (MARS), and M5 Model Tree (MTM5) have been used to provide formulations for prediction of NVI. Soft computing techniques were fed nine input parameters: depth to water level, net recharge, aquifer environment, soil environment, topography, effect of unsaturated area, hydraulic conductivity, land use, and potential risk related to land use. After calculating the vulnerability by soft computing methods, the results showed that the EPR model with Correlation Coefficient (R) of 0.9999 and Root Mean Square Error (RMSE) = 0.2105 has the best performance in the testing stage in comparison with MARS (R = 0.9966 and RMSE = 2.408), M5MT (R = 0.9956 and RMSE = 2.988), and GEP (R = 0.9920 and RMSE = 3.491). Although the EPR and GEP models have more complex mathematical computations than other soft computing models, the MARS and MT model that have quadratic polynomial and multivariable linear structures respectively, can be considered as the best alternative. According to the MARS model, the vulnerability of the region is divided into two categories: very low vulnerability (73.06%) and low vulnerability (26.94%). Overall, the statistical results of soft computing techniques were indicative of effective formulations for evaluating the DRASTIC index.

Groundwater is a valuable and universally distributed resource on Earth. Understanding the spatial and temporal dynamics of groundwater is of utmost importance for effective management. Normally, groundwater levels are recorded at arbitrary points, but groundwater modeling requires interpolating the measured values at specific grid nodes. This study aims to dentify and evaluate the geographical variations of groundwater levels in Türkiye using three geostatistical interpolation techniques. Data from 355 groundwater wells from 1970 to 2019 were used for this purpose. In addition, an investigation of changes in annual average temperature and precipitation was conducted for two different time periods: 1985–2000 and 2001–2016. The results show an increase in the annual average temperature in Türkiye by 0.82 °C during the reference period (1985–2000). Despite regional differences in the precipitation regime, the average annual precipitation in Türkiye has not changed significantly overall. Especially in the Meriç-Ergene, Konya Closed (Konya Kapalı), and Euphrates-Tigris basins, a significant decrease in groundwater levels was observed, even though this decrease is less than 100 m in some wells. After a comprehensive analysis of all these data, possible explanations for the changes in groundwater levels were considered. [ABSTRACT FROM AUTHOR]

The main aim of the study is to perform a high-precision mapping of geological features (lineaments and faults) using advanced gravity processing methods. The main techniques used for gravity data processing are the tilt angle of horizontal gradient (TAHG), the improved logistic filter (ILF), the fast sigmoid edge detector filter (FSF), and an edge detection filter based on the arcsine function (ASF). Before applying these edge detection filters to major geological units of North Cameroon, their effectiveness and performance have been assessed on synthetic gravity data and on random noise incorporated synthetic data. In addition, the Euler deconvolution has been used to estimate the position and depth of anomalous gravity sources in the study region. Using these edge detection techniques, a precise mapping of structural lineaments in the region has been established. It appears that the main structural features are trending along the N-S, NNE-SSW and NE-SW directions. The deepest density anomalies in the region are identified in the NW–SE direction, which coincides well with the extension of the Central and West African rift system in the study area. The advanced edge detection techniques and the Euler deconvolution method have both identified a network of superficial lineaments around longitude 13oN and latitude 8oN, and located between 0 and 4 km depth. The NW–SE trending crustal features outlined in the northeast of the region indicate that the area would have been the target of a uniform tectonic activity. This study is crucial to improve the knowledge of the configuration of fractures network, and to a better exploitation of groundwater resources available in the region. [ABSTRACT FROM AUTHOR]

This study investigates the Batha endorheic basin in Chad, situated east of the Lake Chad basin in the arid to semi-arid Sahelian zone. This region has not yet undergone comprehensive geological and hydrogeological studies. More broadly, the transition zone between semi-arid and arid climates has been minimally explored. This research aims to evaluate the resources and dynamics of this multi-layered system using a combined geology-hydrogeology-hydrochemistry-isotopes approach. The multilayer system includes sedimentary layers (Quaternary, Pliocene, and Eocene) over a crystalline basement. A piezometric investigation of the system shows a general SE–NW groundwater, indicating an interconnection between all layers. Hydrochemical analyses identifies four main facies (calcium-bicarbonate, sodium-bicarbonate, sulphate-sodium, and mixed), primarily controlled by water–rock interaction with secondary influences from base-exchange and evaporation. Saturation indices indicate that these waters are close to equilibrium with the calcite-Mg phases, gaylussite and gypsum. Stable isotopes (oxygen-18 and deuterium) categorize groundwater into three groups: ancient water, recent and older meteoric water mixtures affected by evaporation, and mixtures more heavily impacted by evaporation. Tritium contents reveal three groups: current rainwater, modern water, and sub-modern water. These results indicate that ionic and isotopic differentiations cannot be strictly linked to specific layers, confirming the interconnected nature of the Batha system. The observed heterogeneity is mainly influenced by lithological and climatic variations. This study, though still limited, enhances significantly the understanding of the basin's functioning and supports the rational exploitation of its vital resources for the Batha area's development. Future investigations to complete the present study are highlighted. [ABSTRACT FROM AUTHOR]

This research examines the integration of geological and hydrogeological data in numerical aquifer model simulations, with a particular focus on the urban area of Torino, Italy. The role of groundwater resources in urban sustainability is analysed. The objective is to integrate open-loop geothermal plants into the district heating network of IREN S.p.A. Two case studies are examined: the Torino Nord area and the Moncalieri area, both of which host district heating plants. The work entails the collection and analysis of data from a variety of sources, including geognostic surveys and permeability tests, in order to construct a three-dimensional numerical model of the surface aquifer. Models were built using the public MODFLOW 6 (model of groundwater flow) code and calibrated using PESTHP (High Performance of Model Independent Parameter Estimation and Uncertainty Analysis). Results indicate the potential of urban aquifers as renewable energy sources and the necessity of comprehensive geological and hydrogeological assessments for optimal ground water heat pump (GWHP) system installation. This paper emphasises the significance of sustainable water management in the context of climate change and urbanisation challenges. [ABSTRACT FROM AUTHOR]

Due to the growth of population and industrial advancements in Iran, especially Birjand, the use of groundwater makes the aquifer's balance becomes negative. This negatively affects both quantity and quality conditions of groundwater. To prevent this, suitable water management is necessary for Birjand aquifer. In this study, to overcome negative groundwater balance, the concept of "adjustment factors" is presented. These factors are applied to all types of consumption and make the groundwater balance to be positive. For this aim, a dynamic model of groundwater resources in Birjand aquifer is created in Vensim software. This model helps to determine the groundwater balance. Then, with using dynamic model and particle filter approach in MATLAB software, minimum adjustment factors are achieved. All data and information of Birjand aquifer between 2004 and 2021 are entered into Vensim model; then, under three scenarios, the groundwater balance is computed for the next 5 years (2022–2026). Three scenarios are normal, dry, and wet conditions. In the next step, with the help of particle filter, the minimum adjustment factors for two types of consumptions including agricultural and industrial are computed. The results show that the adjustment factors for all consumptions in dry conditions are much higher than others. For instance, in 2026, the adjustment factor for agriculture in dry conditions is 0.081 while in normal and wet conditions is 0.75 and 0.031, respectively. Also, the findings indicate that applying these adjustment factors to groundwater model has successful results and make the groundwater balance to be positive. [ABSTRACT FROM AUTHOR]

Groundwater resource management in drylands, characterized by climate variability and population growth, is difficult. Exploration and exploitation of groundwater, due to inadequate surface water is very costly. This study employed the analytic hierarchy process (AHP) and GIS to identify groundwater potential (GWP) areas in a semi-arid region of Nigeria. Land-use-land-cover, drainage density, slope, rainfall, static water level, soil, lithology, and aquifer were selected for GWP analysis. Parameter weights were determined using AHP and ranked based on their contribution to GWP by experts. The parameters were then integrated using the weighted overlay tool in ArcGIS 10.5 to produce a GWP map of the study area. Borehole yield data from 245 wells were collected to determine the model accuracy and model validation. Results classified the study area into very high GWP (1.9%), high GWP (8.8%), moderate GWP (62%), low GWP (20.70%) and very low GWP (6.6%). Areas with better GWP include Gurun, Dugol, Zago, Kumbo, Dukku, Doguwa, Riruwai, Dambazau, etc. Moderate GWP areas are widely spread across the state while areas with poor GWP include Sharawa, Kadewa, Koya, Dagar, Jigilawa, Galwanga, Yanganau, Kunchi, Tofa, Tsanyawa, etc. Validation of the AHP model with borehole yield data shows a correlation coefficient of 71.3% giving a good prediction. AHP and GIS can be used to successfully map GWP areas which could serve as an exploration guide for sustainable management of groundwater resources in semi-arid areas.

Asia stands out as the most populous and geographically diverse region globally. The pressing issues of water resource development and the resulting ecological impacts are exacerbated by the region's rapid population growth and economic expansion. Groundwater, a vital source of water in Asia, faces significant disparities in distribution and suffers from unsustainable exploitation practices. This study applies groundwater system theory and categorizes Asia into 11 primary groundwater systems and 36 secondary ones, based on intercontinental geological structures, climate, terrain, and hydrogeological characteristics. As of the end of 2010, Asia's assessed groundwater resources totalled 4.677×109 m3/a, with exploitable resources amounting to 3.274×109 m3/a. By considering the geological environmental impacts of groundwater development and the distinctive characteristics of terrain and landforms, six categories of effect zones with varying distribution patterns are identified. The current research on Asia's groundwater resources, environmental dynamics, and human impacts aims to provide a theoretical foundation for sustainable groundwater management and environmental conservation in the region.

This study aims to examine the causes of the decline in groundwater resources in the perspective of the concept of Islamic economic law, through selected article sources. This research uses a normative doctrinal approach or normative juridical legal research that examines the internal aspects of law or positive regulations. Data collection techniques are carried out through literature studies in the form of secondary data in the form of published articles in journals as basic research material. The condition of the Groundwater Basin (CAT) in Bandung City is now entering a critical condition, one of the visible indications is the decline in groundwater levels by 60-80 percent each year. According to Islamic economic law, everything related to water resources management is believed to be a trust from Allah SWT that must be managed and utilized properly. Islam allows freedom for humans to utilize water resources that are public (general) on the condition that the management must be fair and balanced, not damaging and polluting the environment and natural resources.

Geothermal energy is considered renewable energy that is environmentally friendly and sustainable compared to the conventional energy from fossil fuels. However, uncontrolled geothermal exploitation can cause a decrease in the groundwater table and reservoir temperature, such as in the Jaboi volcano on Weh Island, where a power plant has been built to generate electrical energy with an estimated power of 50 MWe but still has not been operated. A geophysical survey is needed to determine the local hydrothermal system, including groundwater reserves under the surface which can be used to refill the hydrothermal wells during exploitation. This study measured vertical electrical sounding (VES) data at 15 points near the crater and geothermal power plant. In addition, very-low-frequency (VLF) data that pass through the crater were also collected to determine the presence of other hydrothermal resources such as fractures and faults. The results of the 1D least-square inversion show three subsurface models where groundwater resources with low resistivity (< 1.5 Ωm) are found at a depth of 50–100 m. The same results are also obtained from the 2D cross-section model that impermeable resistive anomalies in alluvial and tuff rocks dominate the near-surface area. The layer after groundwater is an impermeable rock in the form of breccia. The results of 2D VES and VLF modeling also show the presence of the Ceunohot and Leumomate faults, which are beneficial as fluid access to the surface. Based on the data analysis, the combination of VES and VLF data can be used to image shallow hydrothermal systems such as groundwater resources and faults in the Jaboi volcano. [ABSTRACT FROM AUTHOR]

Groundwater resilience on small islands, especially low-lying carbonate islands like Tunda, is vulnerable to an expanding population, demand exceeding supply, contamination from human and animal waste, and climate change-related impacts. This study aims to evaluate the resilience of groundwater resources on Tunda Island, Banten, Indonesia, in response to anthropogenic activities and climate change-induced consequences. The data were compiled and collected from the official Indonesian government websites and direct field observations. Typically, the aquifer system of Tunda Island's Quaternary Reef limestone is formed through fissures, fractures, and dissolution, which has low productivity, low to high transmissivity, and a discharge rate of more than 10 L per second. Analysis of climate data reveals that January has the highest average monthly precipitation, with 283 mm, while August has the lowest, with 50 mm. This is proportional to monthly potential water recharge, with amounts of 156,386 m3 in January and only 27,706 m3 in August. The groundwater levels are higher than the mean sea level, ranging from 1.07 to 8.71 m, with flow directions from the inland (recharge) to the coast (discharge). The water quality is generally good, especially on higher terrain located some distance from the coast. However, overall coliform and E. coli levels were marginally elevated. Population growth from the last decade (2012–2022) and ten drought events caused by El Nino and a positive Indian Ocean Dipole (IOD) from 1979 to 2022 have not yet had a significant impact on Tunda Island's groundwater resilience. Similarly, the increase in the number of visitors between 2019 and 2021 has had no effect on the island's water security. However, these anthropogenic and natural stresses will inevitably deplete the island's water supply in the future. Hence, water management strategies, including rainwater harvesting, enhancing water-use efficiency, conserving water through an artificial recharge system, and protecting and restoring coastal ecosystems, were required to maintain the water supply and its sustainability. [ABSTRACT FROM AUTHOR]

This study focuses on identifying fluoride (F‒) concentrations and its health risk assessment (HRA) in drinking water sources in south-eastern Türkiye. Groundwater quality was assessed using some graphical approaches such as Schoeller and Piper diagrams and GIS mapping. Average daily exposure dosages through oral and dermal contact exposure routes were considered to determine the potential health risk of F‒ in groundwater. Groundwater samples were taken from 53 points in spring, summer, autumn, and winter seasons. The results showed that the average annual F‒ concentrations in water resources in the study area were 0.26‒3.62 mg/L. According to the HRA results, the highest F‒ health risk in this region was observed in children, followed by teenagers and adults. This study indicated that there is a strong relationship between the high health risk (4.28 > 3.5) in children and dental fluorosis caused by high F‒ concentration in groundwater. [ABSTRACT FROM AUTHOR]

The availability of groundwater is essential for agriculture, households, and industry. Concerns about its sustainability have been raised due to depletion and pollution in various parts of China. To address this, a life cycle assessment (LCA) is the most suitable approach for implementing integrated sustainability in groundwater resources. This research aimed to investigate the LCA of groundwater in China by analyzing its economic, environmental, and social sustainability based on various research papers conducted between 1999 and 2022, providing insights into the current state of research and suggesting sustainable measures for safeguarding groundwater resources in specific regions and industries in China. The study indicates that specific sector-wise measures should be taken to ensure sustainable groundwater protection in China. Intercropping and drip irrigation systems can be sustainable and effective methods for protecting groundwater in the agricultural sector. New power plants should be constructed in the water-rich southern regions, and long-term water-saving measures should be implemented in China's coal mining industry. All water resources should be integrated into the regional water supply system to reduce dependence on groundwater. Furthermore, more research is needed to investigate all elements of sustainable development in provinces that consume high amounts of groundwater but have limited storage capacity. These recommendations can be helpful to policymakers in promoting the sustainable development of groundwater resources in China. [ABSTRACT FROM AUTHOR]

Abstract The growth of the world population and the problem of food supply have led to the development of agricultural land, particularly in the Third World and in Iran, and thus to a sharp increase in water consumption regardless of the existing water resources. On the other hand, the ever-increasing growth of industries and factories, regardless of the impact on the environment, together with the increase in water consumption, has disturbed the balance of the environment and caused climate change with rising temperatures and increasing pollution. Unfortunately, the management of water resources and the environment is incompatible with the development of agricultural land and the development of industries, and therefore in most countries of the world a situation has arisen in which surface and groundwater resources are at risk. The two main variables, precipitation and water consumption, control groundwater levels. The area studied in this research is the Sarab Plain aquifer located in East Azerbaijan province, Iran. In the Sarab Plain and other plains of Iran, indiscriminate harvesting has led to a significant decline in the groundwater level (in other words, piezometric depth) and subsidence of the plain. The area under cultivation of various agricultural crops such as beans, cucumbers and alfalfa and gardens is about 38,176 ha, irrigated by 739 licensed wells. Agricultural uses on the one hand and industrial and animal uses on the other led to a progressive lowering of the piezometric level of the plain. The average water consumption from the table is currently 53 million cubic meters per year, while the amount of renewable water is 35.81 million cubic meters per year. The data used in the study are monthly precipitation from 19 rain gauge stations, monthly piezometric codes from 78 piezometers converted to piezometric depth, and monthly water consumption from 1886 consumable wells between 2007 and 2022. Individual regression relationships were created between the piezometric depth variable and consumption and precipitation variables. In the first step, a general hybrid exponential relationship between piezometric depth, consumption and precipitation was found. The correlation coefficient value between the calculated and observed piezometric depth was 0.69. Furthermore, the root mean square error and Kling-Gupta were 2 m and 0.57, respectively. In order to apply the hybrid exponential relationship to predict piezometric depth in the coming years, it was necessary to predict precipitation and consumption. To predict monthly precipitation based on its periodicity, the Thomas and Fiering (T&F) consumption forecasting method was used. 20% of the data was compared with calculated data. The result showed, R = 0.815 and RMSE = 0.07 mm between calculated and observed data. Additionally, to predict consumption in the coming years, a suitable regression relationship between consumption and time was constructed, showing a correlation of 0.97 and a root mean square error of 0.0008 mcm with observations. In the second step, precipitation and consumption were predicted for the next 3 years (2023–2025) and piezometric depth were determined for this period by applying them in the hybrid model. The forecast for the next three years shows that the upward trend of the piezometric level will continue. The application of the regression method resulted in a final equation, which is particularly important in view of the stabilization of the piezometric level of the reservoir. This method has no particular limitations and is an appropriate method when accurate consumption water and precipitation statistics are available. The only limitation that can be considered with this method is the movement around the average values and does not take into account the positional fluctuations. This work is new because it calculates groundwater simultaneously using two parameters: precipitation and water consumption. Other similar studies did not use groundwater consumption data.

Groundwater is essential for living earth including ecosystem functioning and development of society worldwide. In recent times, demand and pressure on groundwater resources are progressively increasing over time. Thus, the assessment and management of groundwater resources particularly in semi-arid region are very much crucial. Therefore, the principal objective of the present study is to categorize the groundwater potential areas using advanced machine learning (ML) approaches. In this study, random forest (RF), support vector machine (SVM), and extreme gradient boosting (XGBoost) algorithms have been applied. The accuracy of each model has been estimated using the receiver operating characteristics (ROC) curve. About 60.63%, 65.39%, and 53.75% of areas come under moderate to very low groundwater potential. XGBoost indicates the highest predictive capacity (AUC 0.97). The innovation of this study lies in the combination of hydrological, topographical and geological datasets into machine learning platform. This research will support water resource management worldwide.

In recent decades, geophysical and remote sensing monitoring techniques have advanced to the point where they can be utilized. It is possible to investigate the spatiotemporal mass fluctuations induced by groundwater changes over the Southern Arabian Peninsula (SAP) by combining time-variable gravity data with land surface model outputs and rainfall data. Here are the findings: The average annual precipitation rates for the whole study region were 91.11, 87.6, and 96.61 mm yr−1 during the entire period (2002–2021), period before 2013, and period after 2012, respectively. The southern and eastern parts (Zone I) of the investigated region show modest rainfall rates of 109.6, 105, and 117 mm yr−1 during the whole period, period before 2013, and period after 2012, respectively. The Rub El Khali region (Zone II) is receiving lower precipitation rates of 54.6, 53.3, and 56.5 mm yr−1 throughout the whole period, period before 2013, and period after 2012, respectively. Based on the three distinct gravity solutions, the average Terrestrial Water Storage (ΔTWS) values are computed through the entire period to be − 0.21 ± 0.011, − 0.15 ± 0.013, and − 0.32 ± 0.0107 cm yr−1 for the whole study region, Zone of the southern and eastern regions, and Zone of Rub El Khali, respectively. The whole study region, Zone of the southern and eastern parts, and Zone of Rub El Khali are showing highly negative ΔTWS in the period before 2013, in comparison to slightly negative to slightly positive ΔTWS trends in period after 2012. The average annual change in groundwater storage for the entire study area was calculated at − 0.21 ± 0.011, − 0.29 ± 0.024, and − 0.091 ± 0.038 cm yr−1 throughout the investigated period, period before 2013, and period after 2012, respectively. Zone of Rub El Khali is showing higher negative groundwater storage trend (ΔGWS) averaged at − 0.32 ± 0.104 cm yr−1 throughout the investigated period, whereas Zone of southern and eastern regions is showing lower negative groundwater storage trend of − 0.15 ± 0.013 cm yr−1. Most of the recharge rate occurs in Zone of the southern and eastern regions reaching up to + 0.77 ± 0.092 cm yr−1 by taking the average groundwater withdrawal rate of + 0.92 ± 0.092 cm yr−1 during the whole period. This integrated approach is a valuable and economical method for more effectively assessing the variations of groundwater resources across wide areas.

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In recent decades, geophysical and remote sensing monitoring techniques have advanced to the point where they can be utilized. It is possible to investigate the spatiotemporal mass fluctuations induced by groundwater changes over the Southern Arabian Peninsula (SAP) by combining time-variable gravity data with land surface model outputs and rainfall data. Here are the findings: The average annual precipitation rates for the whole study region were 91.11, 87.6, and 96.61 mm yr−1 during the entire period (2002–2021), period before 2013, and period after 2012, respectively. The southern and eastern parts (Zone I) of the investigated region show modest rainfall rates of 109.6, 105, and 117 mm yr−1 during the whole period, period before 2013, and period after 2012, respectively. The Rub El Khali region (Zone II) is receiving lower precipitation rates of 54.6, 53.3, and 56.5 mm yr−1 throughout the whole period, period before 2013, and period after 2012, respectively. Based on the three distinct gravity solutions, the average Terrestrial Water Storage (ΔTWS) values are computed through the entire period to be − 0.21 ± 0.011, − 0.15 ± 0.013, and − 0.32 ± 0.0107 cm yr−1 for the whole study region, Zone of the southern and eastern regions, and Zone of Rub El Khali, respectively. The whole study region, Zone of the southern and eastern parts, and Zone of Rub El Khali are showing highly negative ΔTWS in the period before 2013, in comparison to slightly negative to slightly positive ΔTWS trends in period after 2012. The average annual change in groundwater storage for the entire study area was calculated at − 0.21 ± 0.011, − 0.29 ± 0.024, and − 0.091 ± 0.038 cm yr−1 throughout the investigated period, period before 2013, and period after 2012, respectively. Zone of Rub El Khali is showing higher negative groundwater storage trend (ΔGWS) averaged at − 0.32 ± 0.104 cm yr−1 throughout the investigated period, whereas Zone of southern and eastern regions is showing lower negative groundwater storage trend of − 0.15 ± 0.013 cm yr−1. Most of the recharge rate occurs in Zone of the southern and eastern regions reaching up to + 0.77 ± 0.092 cm yr−1 by taking the average groundwater withdrawal rate of + 0.92 ± 0.092 cm yr −1 during the whole period. This integrated approach is a valuable and economical method for more effectively assessing the variations of groundwater resources across wide areas. • Gravity application in groundwater storage estimation. • Geophysical monitoring of groundwater resources. • GRACE and GLDAS applications to groundwater storage variation in the Southern Arabian Peninsula. [ABSTRACT FROM AUTHOR]

In order to deal with the increase in human-caused impacts, Saudi Arabia is exploring new groundwater sources. Significant agricultural development in Wadi Al Dawasir has resulted in an overuse of groundwater resources. Constant monitoring of the wadi's groundwater is necessary in order to make informed decisions about the future of the wadi's groundwater resources and the local economy. The rate of groundwater depletion in the Wadi Al Dawasir drainage basin in northern Saudi Arabia was calculated by combining data from the advanced Gravity Recovery and Climate Experiment (GRACE) mission with outputs from a land surface model. The analysis covered the period from April 2002 to December 2021. The results are as follows: (1) the average terrestrial water storage fluctuation (ΔTWS) was calculated at −0.48 ± 0.02 cm yr−1; (2) the average soil moisture storage change (ΔSMS) was calculated at + 0.0008 ± 0.0002 cm yr−1; (3) the average groundwater depletion rate was computed at −0.48 ± 0.02 cm yr−1; (4) the average yearly rainfall data for the Wadi Al Dawasir was 90.1 mm; (5) The surface relief is creating eastward streams that carry surface water downstream; (6) Significant agricultural expansions over the past few decades can be observed through Landsat change detection; (7) Higher sediment accumulation varying from 400 to more than 3000 m is observed in the east, near the Wadi's downstream, where the Wajid aquifer can be found. The integrated approach is a cost-effective and efficient tool for accurately evaluating the variability of groundwater resources over large regions.

The main objective of the study was to delineate Ground Water Potential Zones (GWPZ) in Mberengwa and Zvishavane districts, Zimbabwe, utilizing geospatial technologies and thematic mapping. Various factors, including geology, soil, rainfall, land use/land cover, drainage density, lineament density, slope, Terrain Ruggedness Index (TRI), and Terrain Wetness Index (TWI), were incorporated as thematic layers. The Multi Influencing Factor (MIF) and Analytical Hierarchical Process (AHP) techniques were employed to assign appropriate weights to these layers based on their relative significance, prioritizing GWPZ mapping. The integration of these weighted layers resulted in the generation of five GWPZ classes: Very high, high, moderate, low, and very low. The MIF method identified 3% of the area as having very high GWPZ, 19% as having high GWPZ, 40% as having moderate GWPZ, 24% as having low GWPZ, and 14% as having very low GWPZ. The AHP method yielded 2% for very high GWPZ, 14% for high GWPZ, 37% for moderate GWPZ, 37% for low GWPZ, and 10% for very low GWPZ. A strong correlation (ρ of 0.91) was observed between the MIF results and groundwater yield. The study successfully identified regions with abundant groundwater, providing valuable target areas for groundwater exploitation and high-volume water harvesting initiatives. Accurate identification of these crucial regions is essential for effective decision-making, planning, and management of groundwater resources to alleviate water shortages.

Abstract Introduction: Due to the lack of rainfall and the negative balance of groundwater aquifers in recent years, the use of unconventional water sources such as effluents and sewage for artificial feeding is one of the important methods to deal with decline in groundwater aquifers. In the Borujen-Faradonbeh plain, in order to reduce the effects of drought on groundwater resources, the aquifer of this plain has been artificially fed using the effluent of the Borujen treatment plant. The aim of this study was to investigate the effects of the effluent of Borujen water treatment plant on the quality of groundwater resources in this plain. Methods: To investigate the quality of effluent and its effect on the downstream water of the treatment plant, water wells downstream and upstream were sampled. The samples were immediately transferred to the laboratory and analyzes including the concentrations of Mg, Ca, K Li, Na, S, St, Si, Sc, V, Ba, Cr and V were performed on the samples. Findings: The results showed that except for calcium, potassium and chromium elements which were not statistically significant differences between the water samples taken from the upstream and downstream of the treatment plant (sig> 0.05) but the number of other elements differed between the upstream and downstream wells of the treatment plant. Were significant (sig

In this study, we upscale and simplify hydrostratigraphic information from a detailed model for Denmark to a pan-European scale. This is part of a larger project to develop a harmonised overview of the volume and depth of groundwater resources in a quasi-3D European groundwater resource model. A 10 km grid and a maximum of c. 10 hydrostratigraphic layers were chosen as the common scale for the European database. The Danish information is based on the national water resources model (the DK-model), where the information is significantly more detailed (100 m grid and up to 26 layers). Information was transferred from the DK-model to the quasi-3D model by a method involving computations of mean volumes and expert assessment to reduce layers in each cell. In this process, detailed hydrostratigraphic information is lost, which could otherwise be used for local groundwater flow modelling in Denmark. However, the strength of the quasi-3D model is that it still contains the volumes of all hydrostratigraphic units, both the saturated and unsaturated parts. Hence, the upscaled model can contribute to a relatively precise calculation of European groundwater resources for the quantitative assessment of groundwater status across Europe at a 10 × 10 km scale.

The Songnen Plain is a crucial agricultural area in China, and in the past 20 years, a large number of dry fields have been developed into paddy fields in order to improve land output efficiency. As a result, the effective irrigation area of agriculture has increased annually, and the conversion mode and quantity between surface water and groundwater have changed considerably. It is essential to identify the changes in groundwater resources and their influencing factors for the sustainable development of economy and society. This study evaluates groundwater resources in the Songnen Plain using the water balance method based on meteorological, hydrological and groundwater monitoring data from 2000 to 2020. The results show that the groundwater resources in the region amount to 15.945 billion m3 with precipitation infiltration being the most important component, accounting for 73.09%, which is followed surface water irrigation infiltration and river and ditch infiltration, constituting 14.55% and 10.32%, respectively. Different factors influence groundwater resources in different periods. Compared to 1985, the increase of surface water irrigation infiltration is the primary factor responsible for the increase of groundwater resources, while other recharge sources have decreased during the same period. Compared to 2005, all groundwater resources have increased, with the increase of surface water irrigation infiltration and river channel infiltration being the primary factors.

The evaluation of groundwater quality plays an important role in the management of groundwater. The main objectives of the present work are to develop a novel soft computing framework including Adaptive Neuro-Fuzzy Inference System (ANFIS), Wavelet-ANFIS (WANFIS), Gene Expression Programming (GEP), and Wavelet-GEP (WGEP) for the temporal and spatial estimation of groundwater electrical conductivity (EC) in the East Azerbaijan province, Iran over 2001–2020. The results demonstrate the importance of wavelet transform application; the performance percentage enhancement of the WANFIS and WGEP models compared to the ANFIS and GEP, using the RMSE criterion, ranged from 15.48 to 51.09% and from 5.06 to 86.95%, respectively. All the developed models showed the WGEP superior compared to others. The impact of land use characteristics, climatic conditions, and geological features on groundwater quality showed that there is a direct relationship between the extent of agricultural land, semi-arid climate conditions and groundwater EC amounts. The results demonstrated that the values of EC increase from east to west, indicating the direct exchange of surface and groundwater in the study area. Moreover, groundwater quality changes significantly across the width of the fault, with groundwater EC in the northern part of the fault higher than that in the southern part. HIGHLIGHTS The EC variable of groundwater resources was estimated via single and hybrid-wavelet soft computing approaches.; The impact of land use characteristics, climatic conditions, and geological features on groundwater quality was investigated.; The data de-noising by wavelet approaches have the ability to improve the performance of EC estimation at spatial–temporal scales.;

In the last decade, North Africa has witnessed significant population growth, particularly those bordering the Mediterranean Sea. This led to increased demand for groundwater, which is an essential source for various water uses such as drinking water supplies and irrigation. Generally, human activities play a crucial role in the different quantitative and qualitative changes in groundwater. Now, climate changes such as a decrease in precipitation have also led to a shortage of water resources and a decline in the groundwater table. This paper presents the impact of climate changes on groundwater resources in the Ain Azel region, Setif, northeastern Algeria. The analysis of long-term spatiotemporal variability in rainfall over 63 years (1958–2021) revealed a significant decline in groundwater recharge, especially after 2013. In contrast, the Pettitt and Mann–Kendall tests show increased temperatures with breaks between 1984 and 1986. A piezometric analysis of the alluvial aquifer demonstrated a significant decline in groundwater levels in the last 20 years. Hydrochemical analysis showed that groundwater in the region is dominated by Ca–Mg–Cl water type, which indicates the presence of water salinity phenomenon. Water Quality Index (WQI) analysis showed the deterioration of groundwater in the area, which may be caused by several factors: brine intrusion from the Salt Lake (Sebkha) in the north; the dissolution of evaporites (Triassic) and/or anthropogenic sources of agricultural and industrial origin. Our findings provide an overview summarizing the state of groundwater, which will help improve groundwater resource management in the region in the coming years. [ABSTRACT FROM AUTHOR]

In Iran, similar to other developing countries, groundwater quality has been seriously threatened. Therefore, this study aimed to apply Machine Learning Algorithms (MLAs) in Groundwater Quality Modeling (GQM) and determine the optimal algorithm using the Best–Worst Method (BWM) in Ardabil province, Iran. Groundwater quality parameters included calcium (Ca2+), magnesium (Mg2+), sodium (Na+), potassium (K+), chlorine (Cl−), sulfate (SO4−), total dissolved solids (TDS), bicarbonate (HCO3−), electrical conductivity (EC), and acidity (pH). In the following, seven MLAs, including Support Vector Regression (SVR), Random Forest (RF), Decision Tree Regressor (DTR), K-Nearest Neighbor (KNN), Naïve Bayes, Simple Linear Regression (SLR), and Support Vector Machine (SVM), were used in the Python programming language, and groundwater quality was modeled. Finally, BWM was used to validate the results of MLAs. The results of examining the error statistics in determining the optimal algorithm in groundwater quality modeling showed that the RF algorithm with values of MAE = 0.28, MSE = 0.12, RMSE = 0.35, and AUC = 0.93 was selected as the most optimal MLA. The Schoeller diagram also showed that various ion ratios, including Na+K, Ca2+, Mg2+, Cl−, and HCO3+CO3, in most of the sampled points had upward average values. Based on the results of the BWM method, it can be concluded that a great similarity was observed between the results of the RF algorithm and the classification of the BWM method. These results showed that more than 50% of the studied area had low quality based on hydro-chemical parameters of groundwater quality. The findings of this research can assist managers and planners in developing suitable management models and implementing appropriate strategies for the optimal exploitation of groundwater resources. [ABSTRACT FROM AUTHOR]

The evaluation model of coordinated development of groundwater resources and environmental economy plays a vital role in studying the relationship and ensuring their effective implementation. However, the current research on this evaluation model still has some limitations. In order to solve these problems, this study introduced geographic information system (GIS) technology into the CD evaluation model of GR and environmental economy. A GIS-based evaluation model was proposed and compared with the traditional evaluation model. The effectiveness of GIS in evaluating CD between GR and environmental economy was verified by comparative experiments. The results show that the accuracy of traditional evaluation model (Model 1) on training samples (sample size was 200) was 60.58%. In contrast, the GIS-based evaluation model (Model 2) achieved a higher accuracy of 81.64% in the training sample. When the sample size was increased to 3200, the evaluation accuracy of Model 1 and Model 2 reached 79.66% and 98.68%, respectively. In the test sample size of 800, the accuracy of Model 1 and Model 2 was 74.34% and 98.35%, respectively. These results highlight the validity and applicability of GIS-based evaluation models in evaluating the ecological balance of natural resources and environmental economy. This model provides valuable theoretical support and reference for researchers in this field. [ABSTRACT FROM AUTHOR]

Effective assessment of any region's groundwater resources depends greatly on the levels of the sub-surface water. Since groundwater resources are being overused, the availability of groundwater is in a critical scenario. Quality of the groundwater is deteriorating in numerous regions as a result of the worrisome rate of groundwater table depletion. Depending on how frequently the aquifer under the earth surface is recharged by surface water supplies, groundwater can be kept underground for days, weeks, months, years, centuries, or even millennia. Currently, the utility is increased as compared to availability. The current water demand exceeds the surface water supply. As a result, for the effective management and usage of the priceless natural resources, groundwater potential zones' systematic evaluation is now essential. The understanding about monitoring and a suitable sustainable development strategy for water resources is provided by groundwater potential zoning. The delineation of groundwater potential zoning is influenced by various factors, including rainfall, land-use cover, geological formations, geomorphology, drainage features, slope, etc. To ensure the sustainable groundwater management in the basin, it is essential to locate groundwater potential zones, so that series of recharge structures may be built there to manage aquifer recharge. Remote sensing and GIS are recent techniques that become very crucial tools in accessing, monitoring, and conserving groundwater resources because of their advantages of spatial, spectral, and temporal availability and interpolation of data covering big and inaccessible areas in short amount of time. [ABSTRACT FROM AUTHOR]

Water resources in arid and semi-arid areas are limiting factors for ecosystem health and economic development. Therefore, an accurate and reasonable assessment of ecological water demand is crucial for efficient water resource utilization. In this study, we used vegetation coverage and groundwater depth to assess the state of vegetation growth in the Zhenglanqi, located at the southeastern edge of Otindag Sandy Land. Our results indicate the existence of a statistical power index function between vegetation coverage and groundwater depth scatter plots, where even minor changes in groundwater depth can have a significant impact on vegetation growth. In order to quantitatively assess the impact of subsidence on vegetation ecology, we propose a maximum allowable subsidence level under conditions that maintain normal ecological conditions, based on the initial subsidence depth and ecological guarantee rate. Our findings suggest that regions with shallower initial groundwater depths are more sensitive to changes in their environment than regions with deeper groundwater depths. The total groundwater consumption in the study area was 83 million cubic meters while maintaining an ecological guarantee rate of 80%; thus, while ensuring normal environmental conditions, human exploitation of shallow groundwater accounts for only 16 percent. [ABSTRACT FROM AUTHOR]

Aim and Introduction The health and food security of a country depends on the production of the agricultural sector, and any disturbance in the production process of this sector can threaten the food security of households. Among the challenges affecting the agricultural sector, climate change is of double importance due to its direct impact on crop yield and water resources. The occurrence of climate change through changes in the supply and price of crops, overshadows the producer surplus in this sector. This is despite the fact that, according to previous studies, climate change in the coming decades will be a visible phenomenon in most plains of Iran, and this issue will have negative consequences on water resources and, as a result, on the production of crops and food security. Therefore, considering the importance of food supply in the process of economic development, it is necessary to investigate the impact of food security on climate change and the welfare effects of this phenomenon in Iran. According to this approach, in the present study, the potential effects of different climatic scenarios on the cultivation pattern of the Hamadan-Bahar plain, considering 2018 as the base year, were investigated, and the impact of water resources, production, income and food security in the agricultural sector of this plain was evaluated. Methodology In this study, the dynamic positive mathematical programming(PMP) approach in endogenous price conditions was used. The experimental model, consisting of 18 crops and two types of irrigation technologies, was developed based on the information of 2018 as the base year and in a 20-year planning horizon. This model's objective function is to maximize the present value of net farm income. Resource constraints used in the experimental model include water, land, capital, labor, and chemical fertilizers, with chemical fertilizer restrictions repeated for each nitrogen, phosphate, and potash fertilizers. Finally, the GAMS software and CONOPT3 algorithm were used for data analysis. In the meteorological dimension of the model, the climatic measurement of rainfall was studied in the form of SSP climatic scenarios. Accordingly, the rate of evapotranspiration of crops and, consequently, the production and yield of crops in the region due to climate change were estimated and integrated into the PMP model. Each of these relationships is responsible for providing some of the information needed in the experimental research model. Finally, the dynamic endogenous price optimization framework was estimated as a unit pattern. After evaluating the changes in the income of farmer households and crop pattern in the face of climate change, the food security index was calculated in the different climate scenarios. In the final stage of the research, management strategies were evaluated in the agricultural sector of the Hamadan-Bahar plain to reduce the negative effects of climate change on the food security. Results and Discussion The results showed that the annual cumulative rainfall values of the Hamadan-Bahar plain in the next 20-year period would have a decreasing trend in all climate scenarios, so that in the SSP1, SSP2 and SSP3 scenarios, the average rainfall would be 303, 272 and 252 mm, respectively. Meanwhile, the amount of precipitation in the base year of this research (2018) is reported as 323 mm. Also, the results showed that with the considering an optimistic approach in predicting climate changes (SSP2 scenario), along with the increase of extraction from underground water sources by 13%, the increase in average price of agricultural products by 34% and the decrease in production by 5% in the 20-year planning period compared to the base year, the present value of net producer income and the food security index in the agricultural sector of the region would decrease by 17 and 11 percent, respectively. However, the adoption of management strategies such as the optimal deficit irrigation would improve the food security of the plain by 11 to 15 percent. Conclusion The change in the climate conditions in the coming years would have negative effects on the food security conditions in the agricultural sector of the Hamadan-Bahar plain. In this situation, considering that it is impossible to avoid different forms of climate scenarios, it is necessary to apply strategies to adapt to the mentioned phenomenon. Based on this, the optimal deficit irrigation, as a management strategy, was investigated, and the results confirm the positive effect of this strategy in improving the food security index in the region. Therefore, according to the results, management strategies with emphasis on deficit irrigation in the agricultural sector of Hamadan-Bahar plain should be put on the agenda. Keywords: Rainfall, Production, Groundwater Resources, Dynamic Pattern, Food Insecurity JEL Classification: C02, C22, C33, C46, C61, Q25, Q54

This paper presents updated water handpump functionality estimates for eight councils in the Mvila Division, southern region of Cameroon. The methodological approach was based on a technical inspection of 647 water points (181 boreholes and 466 wells) and semi-structured interviews with 500 stakeholders, including 103 water point committee members, 389 water users, and 8 water experts. According to the findings, one out of every three hand pumps is inoperable. Based on this rate, approximately 1.3 billion CFA francs (approximately 2 million US dollars) invested by the government, communities, and development partners are immobilized and do not generate any benefit for affected rural communities. This high level of handpump non-functionality is due to the low economic viability of water point management, the poor functionality of water point committees, and the poorly structured handpump maintenance chain. The pooling of water point management at the scale of the Mvila Division appears to be an avenue to be explored to improve the functionality of the handpump. HIGHLIGHTS This paper presents updated water handpump functionality estimates for eight councils in the Mvila Division, southern region of Cameroon.; Results show that one out of three handpumps is non-functional.; The factors that influence the functionality of handpumps are economic, institutional, managerial, and technical.;

This research examines the integration of geological and hydrogeological data in numerical aquifer model simulations, with a particular focus on the urban area of Torino, Italy. The role of groundwater resources in urban sustainability is analysed. The objective is to integrate open-loop geothermal plants into the district heating network of IREN S.p.A. Two case studies are examined: the Torino Nord area and the Moncalieri area, both of which host district heating plants. The work entails the collection and analysis of data from a variety of sources, including geognostic surveys and permeability tests, in order to construct a three-dimensional numerical model of the surface aquifer. Models were built using the public MODFLOW 6 (model of groundwater flow) code and calibrated using PESTHP (High Performance of Model Independent Parameter Estimation and Uncertainty Analysis). Results indicate the potential of urban aquifers as renewable energy sources and the necessity of comprehensive geological and hydrogeological assessments for optimal ground water heat pump (GWHP) system installation. This paper emphasises the significance of sustainable water management in the context of climate change and urbanisation challenges.

Groundwater temperature is a critical control on groundwater quality, geothermal system efficiency and ecosystem dynamics in receiving surface waters. Despite the known importance of groundwater temperature, there is a lack of dedicated aquifer thermal monitoring across spatial and temporal scales. Pressure transducers and other sensors installed in groundwater monitoring well networks often record temperature as a secondary function, but these comprehensive groundwater temperature data sets are seldom analysed. In this study, we analysed seasonal, interannual and spatial patterns of shallow groundwater temperatures from a regional groundwater monitoring network in Nova Scotia, Canada and compared these subsurface temperature data to air temperature data from nearby climate stations using linear regressions and Fourier analysis. The results showed that seasonal groundwater temperatures were damped (with seasonal amplitudes 3.6%–42% of air temperature amplitudes) and lagged (phase shifted 43–145 days) compared to air temperature, with notable year‐to‐year variations in both damping and lagging. Results also highlighted the role of snowpack thickness on the lowest mean monthly groundwater temperatures. Given potential impacts of climate change, land cover change, urbanization and geothermal energy development on groundwater temperatures, we encourage water authorities and regulators to begin or enhance aquifer thermal monitoring and provide guidance for capitalizing on existing monitoring well infrastructure to track temperature dynamics and changes. [ABSTRACT FROM AUTHOR]

The recent study presents main results of a re-evaluation of the mineral water and geothermal energy of the Devin hydro-mineral deposit, Smolyan region. The deposit occupies an area of about 16 km³, and coincids with the narrow valley of the Devinska River. Hydrochemical methods are applied and chloro-alkaline relations are determined to evaluate the ion exchange and the genesis of the mineral water. The reservoir occurred in a Paleogene tectonic graben filled with breccia-conglomerates, conglomerates, sandstones, and argillites. The mineral water has a composition expressed in equivalent units for cations: Na+ > Mg2+ > Ca2+ > K+, and for anions: (CO3- + HCO3-) > SO42- > Cl-. The water is of NaHCO3- type, fluorine with a fluoride concentration of 3.7-7.0 mg/L and H2SO3 from 44.62 to 64 mg/L. The TDS content of 247 to 316 mg/l, isothermal to hyperthermal in depth. The regional resources are estimated at 21 l/s and the local resources are estimated at 17.23 l/s. The local geothermal energy of the Devin reservoir reaches 1.212 M J/s. [ABSTRACT FROM AUTHOR]

Water harvesting is a critical component of any approach to alleviating India's water crisis. Traditional rainwater harvesting systems are found in every region of the country. Haveli is one such system found in almost every village in the Bundelkhand region, Uttar Pradesh, India. A defunct Haveli in the Parasai-Sindh watershed of Jhansi district, Uttar Pradesh, was rejuvenated by providing a cement concrete core wall to the earthen embankment to address the problem of breaching, and the existing outlet was also expanded. This study was conducted from 2013 to 2019 to analyse the hydrology of the rejuvenated Haveli and to understand its impact on surface-water availability and recharging groundwater. The study period was divided based on long-term southwest monsoon (SWM) as wet (SWM > 20%), normal (SWM ± 20%) and dry (SWM < 20%) years. It was found that the Haveli could harvest about 1.91-2.0 times, 1.13-1.72 times and 0.2 times its capacity during a wet, normal and dry year, respectively. There was a 1.41 m difference in hydraulic head between pre- and post-Haveli rejuvenation in a wet year, whereas, a normal year, the difference was 2.71 m. [ABSTRACT FROM AUTHOR]

Water shortage is a universal resource problem worldwide, especially in arid and semi-arid regions. The Hami Basin is one of the most water-scarce areas in China, with low average annual precipitation and high evaporation. In order to effectively monitor groundwater problems, this paper proposes a study on the status and change characteristics of groundwater resource pollution in the Hami area based on sustainable development strategies, aiming to study the changes in groundwater in the Hami area and propose corresponding measures to reduce pollution and save water resources. The method of this article is to introduce the groundwater quality evaluation method, analyze the environmental carrying capacity and then study the evolution process of the groundwater environment in the Hami area. The function of the method is to assess the ecological risk of groundwater and the risk of groundwater pollution, and to analyze the changes in the carrying capacity of the local environmental system. This paper uses groundwater detection experiments to detect the current status of groundwater resource pollution and the characteristics of groundwater changes in the Hami area, and establish a groundwater numerical model in the Hami area.