Rice (Oryza sativa L.) is a staple crop critical for food and nutritional security in India, but its cultivation under traditional puddled transplanted rice is highly resource-intensive, demanding excess water, labour and energy. With growing concerns about groundwater depletion, energy scarcity and rising production costs, resource-efficient alternatives such as dry direct-seeded rice (DDSR) and wet direct-seeded rice (WDSR), coupled with improved irrigation regimes, are gaining importance. The present field investigation was conducted during the kharif seasons of 2021 and 2022 at the Agricultural Research Station, Kampasagar, Telangana, to evaluate the energetics of rice under three establishment methods and three irrigation regimes [conventional submergence, saturation and alternate wetting and drying irrigation (AWDI)]. Results revealed significant differences among establishment methods for specific energy, energy productivity and energy efficiency ratio, whereas irrigation regimes showed non-significant effects. Among the establishment methods, WDSR recorded the lowest specific energy requirement (5.8 MJ kg-1), the highest energy productivity (0.18 kg MJ-1) and superior energy efficiency ratio (2.6), thereby outperforming transplanted rice (TPR) and DDSR. This advantage is particularly relevant under conditions of groundwater depletion and rising energy costs, as rice alone accounts for nearly 50–60 % of irrigation water withdrawals in India, while groundwater pumping contributes about 25 % of total farm energy costs. Across irrigation regimes, AWDI lowered specific energy by ~7–8 % compared to conventional submerged (CS) (5.9 vs. 6.4 MJ kg-1) and improved energy productivity by ~6–12 % (0.17–0.18 vs. 0.16–0.17 kg MJ-1), with efficiency ratio gains of ~4–9 % (2.4–2.6 vs. 2.3–2.4), although differences were statistically non-significant. Overall, WDSR combined with AWDI emerged as the most energy-efficient approach, ensuring sustainable resource utilization without compromising yield. Energetics evaluation thus highlights the potential of alternative establishment methods and water-saving irrigation practices to enhance energy-use efficiency, supporting eco-friendly and economically viable rice cultivation in semi-arid canal command regions.

This study aims to analyze the application of water accounting in supporting agricultural sustainability in North Gorontalo City, focusing on the issue of limited access to irrigation water faced by farmers. The scope of the research includes difficulties in obtaining water from irrigation channels due to sub optimal infrastructure, forcing farmers to rely on groundwater pumped at high cost. This condition directly increases production expenses and reduces farmers’ income. The study employs a descriptive qualitative approach, with data collected through field observations and in-depth interviews with farmers, irrigation managers, and relevant government officials. The collected data were analyzed thematically to identify the root causes and potential solutions for more efficient water management. The findings indicate that farmers urgently need a stable supply of water from irrigation channels to maintain crop productivity, particularly rice. The operational costs of groundwater pumping were proven to reduce farmers’ profit margins. Furthermore, there has been insufficient attention and no concrete steps from the local government to repair irrigation channels or provide alternative solutions. This study highlights the need for implementing a water accounting system as a basis for planning efficient water management, as well as encouraging active collaboration between the government and farmers to achieve sustainable agriculture.

This research examines both groundwater quality and hydrogeological characteristics of the Misurata locality on the Mediterranean Sea in Libya. The area is characterized by different land elevations, while its semi-arid climate exists with geological formations that span from the Miocene to the Quaternary periods. The water resources in this area experience problems because of excessive groundwater pumping, which causes saltwater to enter drinking water. Fifty groundwater samples were collected from wells across Misurata to perform chemical tests and contamination evaluations. The laboratory tests evaluated nitrates and chlorides, phosphates, and heavy metals (cadmium, lead, and zinc) against drinking water and irrigation water standards.The research data demonstrated that agricultural waste and wastewater entry into the ground caused nitrate and phosphate contamination to rise in the groundwater throughout Misurata, generally the southeastern and central parts have shown the highest contamination levels. The chloride measurement demonstrated that seawater intrusion followed the same pattern as other Libyan coastal aquifers, which experienced the intrusion due to excessive pumping. The industrial sections of the city displayed high values of Cadmium and lead concentrations, which endangered both environmental stability and human health. The zinc measurements in all wells exceeded established international limits because established that industrial activities which generate metal processing waste and air pollution lead to high zinc concentrations in surface water (IRC, 2014). The zinc measurements in all wells showed a consistent pattern throughout the entire study.The groundwater contamination in Misurata results from industrial operations and excessive groundwater extraction with an inadequate wastewater treatment practices. This research demonstrates that proper water resource management for drinking and agricultural requires a groundwater system with strict well management rules and ongoing water quality checks and public awareness programs.

99Tc is a long-lived radioactive fission productwhosesubsurface mobility is governed by redox conditions. Under oxic conditions,soluble Tc­(VII)­O4– is mobile, whereasunder reducing conditions, poorly soluble Tc­(IV) phases limit transport.Microcosm studies have frequently reported TcO2-like solidsand, less consistently, Tc­(IV)-sulfides. The stability of Tc­(IV)-sulfidesunder environmentally relevant conditions remains unclear. Here, weused flowing sediment columns representative of the Sellafield subsurfaceto examine Tc speciation and stability over ∼1 year. Underreducing conditions, >90% of added TcO4– (400 μg) was retained under both Fe­(III)- and sulfate-reducingconditions. X-ray absorption spectroscopy showed TcO2-likephases dominated in Fe­(III)-reducing columns, while Tc­(IV)-sulfidesdominated after sustained sulfate reduction. Sequential extractionsindicated that Tc in sulfidic sediments was more recalcitrant (≤23%released by weak acids) than in Fe­(III)-reducing systems (∼60%released). With oxic groundwater pumping, effluent Tc sourced fromthe sediments rose rapidly. Over 160 days, the sulfidic columns remobilized∼25% of their Tc inventory compared to ∼50% in Fe­(III)-reducingcolumns. The Tc­(IV)-sulfides also gradually oxidized to form TcO2 phases. While Tc­(IV)-sulfides may enhance Tc retention underreducing conditions, TcO2 phases more likely govern 99Tc mobility during long-term redox cycling. Our findingsprovide new constraints for modeling Tc fate at contaminated sitesand in radioactive waste disposal.

Simplified theoretical analyses of lagging Darcy flow and land subsidence in a groundwater pumping system of three horizontal layers: An elastic thin plate approach

ABSTRACT India's agricultural sector increasingly relies on groundwater for irrigation, leading to depleting groundwater resources in various parts of the country. Historically, surface water storage structures known as ‘tanks’ were used for millennia in India to store rainwater for irrigation. Their use declined over time and due to the increased groundwater pumping in the 20th century, but recent revitalisation efforts aim to improve water availability and support sustainable livelihoods. Despite this resurgence, the role of irrigation tanks in recharging groundwater is not yet fully understood. This study aims to evaluate the effectiveness of tanks in facilitating groundwater recharge using numerical modelling with Hydrus 2D. Time series for tank water levels were reconstructed using satellite images from Planet Labs. The findings confirm that irrigation tanks contribute to groundwater recharge, particularly when constructed in a cascade system. As the cascade of tanks, where water flows from upstream to downstream tanks, is supplied by rivers, both tanks are almost constantly filled with water. This causes recharge throughout the year, except on some days in the dry season. Recharge rates strongly depend on both the aquifer's hydraulic conductivity and the characteristics of the tank floor. The results show the effect of measures such as the removal of accumulated sediments and thus provide insights to optimise the tanks' dual function as reservoirs for irrigation as well as aquifer recharge structures.

Relief wells’ performance gradually decreases over time due to physical and chemical clogging during the operations. Pumping at relief wells is an economic and feasible method to improve the performance of relief wells instead of installing new wells. This paper proposed multi-objective optimization approaches for determining relief well pumping strategy (e.g., pumping rate and the number of pumping wells). Firstly, a three-dimensional transient seepage of Yangtze River levee with relief wells is simulated using MODFLOW model. The well pumping strategy is optimized by minimizing the average safety factor deficit to a defined threshold at the cross-section of relief wells, minimizing total pumping rate and minimizing the number of pumping wells. Then, non-dominated sorting genetic algorithm-II (NSGA-II) is used to derive the alternative optimal pumping strategies. To reduce enormous computational burden within the multi-objective optimization, a nonparametric regression procedure, i.e., multivariate adaptive regression splines (MARS), is used to establish an intelligent surrogate model for evaluating the safety factor of levee with relief wells instead of repetitive MODFLOW simulations. Finally, the best pumping strategy among Pareto solutions is selected by entropy weight and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). The proposed approaches are tested on the Yangxin Yangtze River Dike in Hubei Province. Results show that the proposed approaches can objectively determine the final optimal relief well pumping operation by balancing the safety of levee and economic efficiency. Compared with the traditional method, the proposed approaches only require pumping groundwater from two wells for the study area, where the number of pumping wells is reduced by 50%, and the total pumping rate is decreased by 37.5%. Moreover, the proposed approaches significantly reduce the computation time from several thousand hours of repetitive numerical simulations to just one minute, providing a feasible tool for relief well maintenance.

Coal remains the primary energy source in China despite its declining role in global energy consumption. While coal mining ensures energy security and economic growth, it has substantial environmental consequences. This study synthesizes secondary data and peer-reviewed literature to examine three major impacts of coal mining: geological disruption, water resource depletion and pollution, and atmospheric contamination. Results show that underground mining causes land subsidence and topographical deformation, while groundwater pumping accelerates aquifer depletion and acid mine drainage formation. Additionally, spontaneous combustion of coal gangue and emissions of SO₂, NOₓ, CO, and CH₄ contribute to severe air pollution and climate change. The analysis highlights the urgent need for improved mine water management, land reclamation, and methane mitigation strategies. Future research should integrate field-based monitoring with multi-dimensional ecological assessments to provide a scientific basis for sustainable mining practices and low-carbon transitions.

Abstract Springs are one of the most vital components of desert ecosystems and an essential element in the cultural traditions and heritage of indigenous peoples. Bonanza Spring on the flank of the Clipper Mountains is the largest freshwater spring in the Eastern Mojave Desert, California, USA and lies in the Mojave Trails National Monument. Like many isolated springs in the arid southwestern United States, it can be vulnerable to changes in climate, vegetative changes (particularly those associated with the encroachment of non-native species), and lowering of local piezometric surfaces due to groundwater extraction and pumping wells. There are proposals to export groundwater from this area to urban and suburban areas in southern California, making the potential relationship and hydrogeologic connectivity between Bonanza Spring and agricultural (Cadiz) irrigation wells a resource management concern. In this study, the similarity or dissimilarity of the chemistry and physical properties of groundwater issuing from Bonanza Spring versus Cadiz agricultural wells in the lower Fenner Watershed and Bristol/Cadiz Basin, located over 22 km (13.7 miles) to the southwest and approximately 400 m (1,315 feet) lower in elevation, is considered through a series of concurrent sampling and analysis of groundwater chemistry and isotopic content. Specifically, spring and well water in the Cadiz agricultural area were sampled and analyzed for over a year’s time, also involving evaluation of aqueous physical properties and related biological attributes in the spring ecosystem. Dissimilarities in water quality were found between spring and well waters, suggesting no or poor hydraulic connection between the two.

Integration of new methodologies in monitoring native fish habitat and populations in the southwestern U.S.

Land subsidence is widely present across the globe and brings catastrophic hazards. The well-acknowledged mechanism of subsidence is groundwater pumping, which leads to the reduction of hydraulic head and hence increases the effective stress, resulting in the vertical compaction of unconsolidated sediment. Here, we propose a hypothesis that subsidence in the coastal areas might be caused by osmotic effects, given the presence of seawater intrusion. The hypothesis is corroborated by simulating fluid flow, solute transport, and elastic deformation of multi-layered aquifer-aquitard systems. The simulations potentially cover a variety of natural environments by varying concentration, hydraulic head, thickness of aquitard, and hydraulic conductivity. We find that osmotic effects due to seawater intrusion play a non-negligible role in controlling subsidence in our studied cases, suggesting that future work on subsidence in areas impacted by seawater intrusion should fully incorporate osmotic effects to improve our understanding and prediction of subsidence.

The escalating pressure on water resources in agricultural regions has become a catalyst for water conflicts. The adoption of innovative approaches to estimate actual evapotranspiration (ETa) offers potential solutions to mitigate conflicts related to water usage. This research presents the application of a remote sensing-based methodology for estimating actual evapotranspiration (ETa) based on a two-source energy balance model (TSEB) for riparian vegetation in Nebraska, US using the Spatial EvapoTranspiration Modeling Interface (SETMI). Estimated results through SETMI and field data using the eddy covariance system (EC) considering the period 2008–2013 were used to validate the energy balance components and ETa. Modeled energy balance components showed a strong correlation to the ground data from EC, with ET presenting R2 equal to 0.96 and RMSE of 0.73 mm.d−1. In 2012, the lowest adjusted crop coefficient (Kcadj) values were observed across all land covers, with a mean value of 0.49. The years 2013 and 2012, due to the dry conditions, recorded the highest accumulated ETa values (706 mm and 664 mm, respectively). Soybeans and corn exhibited the highest ETa values, recording 699 mm and 773 mm, respectively. Corn and soybeans, together accounting for a substantial portion of the land cover at 15% and 3%, respectively, play a significant role. Given that most fields cultivating these crops are irrigated, both pumped groundwater and surface water directly impact the water source of the Republican River. The SETMI model has generated appropriate estimated daily ETa values, thereby affirming the model’s utility as a tool for assisting water management and decision-makers in riparian zones.

The Mekong Delta in Vietnam is a low - lying, densely populated, and agriculturally important region, making it highly vulnerable to subsidence and sea - level rise. Recent years have seen accelerated subsidence, reaching several centimeters per year, primarily due to intensive groundwater pumping. Previous large - scale InSAR studies have been limited to short timeframes , applied linear assumptions and simplified LOS - to - vertical projections, potentially misrepresenting actual subsidence dynamics. In this study, we assessed the feasibility of long - term (2015 - 2023) subsidence monitoring using Sentinel - 1 InSAR , processing a total of 708 descending - mode image s with Persistent Scatterer (PS) InSAR and Small Baseline Subset (SBAS) InSAR . Unlike earlier work, our analysis explicitly addresses the challenges of processing large datasets in a coherence - limited delta environment and provides the first systematic comparison of PS and SBAS performance over an eight - year period. We show that while PS InSAR identified ~ 56 4, 000 points, primarily in stable urban areas , it largely failed in non - urbanised regions . In contrast, SBAS InSAR yielded ~ 1,200, 000 coherent points , with superior sensitivity to spatially variable subsidence across the delta. By linking InSAR point densities to land cover classes, we further demonstrate that SBAS is particularly effective in vegetated and agricultural areas, whereas PS points remain concentrated in built - up zones. These finding s demonstrate that SBAS InSAR is more robust for delta - wide, long - term monitoring. Given the absence of in - situ validation over the studied period ( permanent GNSS stations , levelling benchmarks , extensometers ), InSAR currently remains the only comprehensive method for tracking deformation across the Mekong Delta. Our findings establish both the feasibility and the methodological requirements for reliable long - term InSAR - based monitoring in subsiding deltas, and highlight the need for future integration with independent ground - based measurements.

Enhanced toluene remediation in low-permeability zone by injecting rhamnolipid-coated ozone micro-nano bubble water combined with groundwater pumping

Can karst aquifer for public supply threatened by lead smelting be sustainably managed? Part II: Evidence from groundwater modeling.

ABSTRACT Groundwater pumping near large rivers is commonly used to prevent agricultural water shortages, yet the impacts of high extraction rates on groundwater systems require clarification. In Dalat County along the Yellow River, intensive extraction has reshaped groundwater flow patterns, forming a cone of depression that reversed groundwater discharge to recharge from the river. The values of groundwater δ18O, EC and Cl within the cone are lower than in the Yellow River irrigation zones. Paradoxically, groundwater in the cone exhibits an older groundwater age, confirming the shift of groundwater flow patterns. This stems from shallow, salinized aquifers in river-irrigated areas, where increased leaching after river recharge elevated EC/Cl despite younger groundwater ages. The cone's depleted δ18O signals suggest mountain-sourced recharge from southern highlands. These findings elucidate recharge dynamics critical for sustainable water management in changing environments.

Intensive groundwater extraction and a severe 2021 drought have worsened land subsidence in Taiwan's Choshui Delta, highlighting the need for effective predictive modeling to guide mitigation. In this study, we develop a machine learning framework for subsidence analysis using electricity consumption data from pumping wells as a proxy for groundwater extraction. A long short-term memory (LSTM) neural network is trained to reconstruct missing subsidence records and forecast subsidence trends, while an artificial neural network links well electricity usage to groundwater level fluctuations. Using these tools, we identify groundwater-level decline from pumping as a key driver of subsidence. The LSTM model achieves high accuracy in reproducing historical subsidence and provides reliable predictions of subsidence behavior. Scenario simulations indicate that reducing groundwater pumping, simulated by lowering well electricity use, allows groundwater levels to recover and significantly slows the rate of land subsidence. To assess the effectiveness of pumping reduction strategies, two artificial scenarios were simulated. The average subsidence rate at the Xiutan Elementary School multi-layer compression monitoring well (MLCW) decreased from 2.23 cm/year (observed) to 1.94 cm/year in first scenario and 1.34 cm/year in second scenario, demonstrating the potential of groundwater control in mitigating land subsidence. These findings underscore the importance of integrating groundwater-use indicators into subsidence models and demonstrate that curtailing groundwater extraction can effectively mitigate land subsidence in vulnerable deltaic regions.

Groundwater depletion is a critical global challenge, particularly in intensively cultivated drylands, with few documented cases of successful recovery. Here, we report a striking reversal of long-term groundwater decline in the North China Plain, one of the world's most severely depleted aquifers. Based on a comprehensive analysis of groundwater levels from over 2000 monitoring wells spanning the past two decades, we show that groundwater levels have risen at an average rate of ~0.7 m year-1 since 2020, surpassing 2005 levels by 2024. This recovery is driven by a combination of large-scale surface water diversion from the humid south and stringent groundwater pumping regulations, further amplified by wet years (e.g., 2021). From 2005 to 2023, these policies reduced annual groundwater abstraction by ~12 km3 and increased environmental water allocations to over 7 km3 since 2021, promoting aquifer recharge and restoring environmental flows. Our findings demonstrate that rapid, large-scale groundwater recovery is achievable through integrated water management and targeted policy interventions across extensive regions (~130,000 km2).

At the turn of the century, irrigators in San Luis Valley (SLV), Colorado confronted a reality of precipitously dropping water levels of their shared groundwater resource stemming from their collective overextraction. Rather than continuing with business as usual—risking further declines and potential state intervention—they decided to self-organize and agreed to adopt a pumping fee, substantially increasing the cost of water—one of their key agricultural inputs. This innovative approach to conservation departs from those commonly championed by many groundwater stakeholders, who tend to favor conservation policies that decrease—not increase—costs, such as subsidizing more efficient irrigation technology or paying farmers to fallow their land. Despite few empirical examples of the introduction of a pumping fee, there are sound economic reasons to consider this approach. In this article, we review the adoption of this home-made policy, discussing the process and reasoning behind the stakeholders’ choices, the economic theory that supports it, and some of the agricultural, hydrological, and social outcomes that have resulted from it. The case study illuminates the potential benefits of a groundwater fee but also highlights that policy choices are multifaceted and what works in one scenario does not imply it is a panacea. The article concludes with a discussion of a recent and surprising policy move: SLV farmers have decided to increase the primary groundwater pumping fee exponentially to $500 per acre-foot (10 times the original fee in 2009). We discuss how this new policy represents a shift from a Pigouvian tax structure to what resembles more of a cap-and-trade system. While the results of this latest policy innovation are still unknown, the eventual results promise to be instructive not only to SLV but also to other areas facing similar water scarcity issues.

ABSTRACT The Emilia-Romagna region, one of the most agriculturally productive regions in Italy, heavily relies on groundwater for irrigation. Climate change, with increasingly frequent and severe droughts, is expected to increase dependency on groundwater resources. To assess climate change impacts on the regional aquifer system, a high-resolution numerical groundwater flow model of a portion of Emilia-Romagna is implemented in MODFLOW 6, building on the data and previous model developed by the Regional Agency for Prevention, Environment and Energy of Emilia-Romagna (Arpae). The model simulates long-term scenarios, considering reductions of precipitation and increased groundwater abstraction over 12 years. Results indicate that the aquifer system is vulnerable to droughts, with intensified effects when groundwater pumping increases. Furthermore, areas where the impacts of reduced precipitation and higher abstraction are particularly pronounced are identified. These findings provide critical insights for the implementation of sustainable management strategies for the regional aquifer system during long-term droughts.