Sustainable Use Of Groundwater Research Articles

Groundwater governance for improving city water resilience in Cape Town, South Africa

Until recently, Cape Town, South Africa's second largest city relied entirely on surface water for water supply. Low rainfall between 2015 and 2018 caused extreme water scarcity and water insecurity, even though the city is located on a number of significant aquifers. Water demand management measures instituted during the drought accelerated the transition to a decentralized, hybrid system. Groundwater played an important role in this transition, particularly for households, the bulk users of utility-supplied water. The current water governance and management is ill-equipped for the emergent hybrid system underpinned by an engineering approach that treats water narrowly as a resource for supply and use. This approach is problematic because it does not adequately consider water as one of multiple systems comprising the environment that supplies critical ecosystem services. Even though the City of Cape Town, as local government, effectively does not have a groundwater management role, its responsibilities for water and sanitation services, spatial planning, land-use management and environmental management all intersect with groundwater management. Significant water governance reform is therefore necessary for sustainable groundwater use and resilience in Cape Town and other South African cities.

Labor markets: A critical link between global-local shocks and their impact on agriculture

Labor markets can shape the impacts of global market developments and local sustainability policies on agricultural outcomes, including changes in production and land use. Yet local labor market outcomes, including agricultural employment, migration and wages, are often overlooked in integrated assessment models (IAMs). The relevance of labor markets has become more important in recent decades, with evidence of diminished labor mobility in the United States (US) and other developed countries. We use the SIMPLE-G (Simplified International Model of agricultural Prices, Land use, and the Environment) modeling framework to investigate the impacts of a global commodity price shock and a local sustainable groundwater use policy in the US. SIMPLE-G is a multi-scale framework designed to allow for integration of economic and biophysical determinants of sustainability, using fine-scale geospatial data and parameters. We use this framework to compare the impacts of the two sets of shocks under two contrasting assumptions: perfect mobility of agricultural labor, as generally implicit in global IAMs, and relatively inelastic labor mobility (‘sticky’ agricultural labor supply response). We supplement the numerical simulations with analytical results from a stylized two-input model to provide further insights into the impacts of local and global shocks on agricultural labor, crop production and resource use. Findings illustrate the key role that labor mobility plays in shaping both local and global agricultural and environmental outcomes. In the perfect labor mobility scenario, the impact of a commodity price boom on crop production, employment and land-use is overestimated compared with the restricted labor mobility case. In the case of the groundwater sustainability policy, the perfect labor mobility scenario overestimates the reduction in crop production and employment in directly targeted grids as well as spillover effects that increase employment in other grids. For both shocks, impacts on agricultural wages are completely overlooked if we ignore rigidities in agricultural labor markets.

Comparing water related indicators and comprehensively evaluating cropping systems and irrigation strategies in the North China Plain for sustainable production

The fully irrigated winter wheat–summer maize double cropping system (DWM) has caused groundwater overexploitation and aggravated water scarcity in the North China Plain (NCP). Therefore, it is necessary to select alternative cropping systems with effective irrigation strategies to maintain the sustainable use of groundwater and maintain crop productivity. However, the evaluation indicators, especially the water-related indicators of cropping systems and irrigation strategies in current studies are not consistent and it is difficult to obtain a comprehensive evaluation result. Hence, to overcome these challenges, this study reviewed and compared groundwater indicators, water use indicators, water production performance indicators and output indicators, and summarized twelve evaluation combinations. Four evaluation combinations with grain yield as output indicator were selected to comprehensively evaluate the cropping systems and irrigation strategies developed by Agricultural Production Systems sIMulator (APSIM) at a typical site in the NCP in the past 52 years. The indicator weights were determined by analytic hierarchy process, entropy weight method, random forest algorithm and principal component analysis. Evaluation results showed that when the main goal was to guarantee food safety or improve the beneficial water use, the DWM was selected as the best choice and the WMM (winter wheat–summer maize → spring maize system, three crops in two years) was the alternative cropping system. Under this condition, water saving irrigation should be vigorously developed to reduce groundwater exploitation. When the four indicator types had the same weight, the DWM under rainfed was the best choice to improve evapotranspiration use efficiency and precipitation use efficiency; the monocropping spring maize system under normal irrigation strategy was the best choice to reduce water footprint. The WMM under rainfed was the alternative choice to improve evapotranspiration use efficiency, improve precipitation use efficiency and reduce water footprint. The evaluation methods proposed in this study could be used as reference in the comparison of cropping systems and irrigation strategies in other water-related situations.

Alleviating groundwater depletion while realizing food security for sustainable development

Groundwater depletion was one of humanity's greatest challenges for both food and environmental security. Here we tried to address these challenges through a meta-analysis in three major global groundwater-depleted agricultural regions and a case study with the long-term field experiment with factorable and systematic solutions. We showed groundwater depletion was particularly evident in the important regions for global food production, such as the High Plains of the United States, the Ganges Plains of India, and North China Plain, resulting from a 262.5 mm gap between crop water demand and rainfall. In order to solve this problem, the long-term field study in North China Plain indicated that the factor adjustment (minimum irrigation) within the traditional system and systematic change from traditional wheat-maize rotation to double-cropped maize could achieve both sustainable groundwater use and high calorie yield, accompanying by low integrated environmental impacts. Our results provided essential insights in similar areas for the United Nations Sustainable Development Goals for food and environmental security.

Improvement of Water and Nitrogen Use Efficiencies by Alternative Cropping Systems Based on a Model Approach.

The conventional double cropping system of winter wheat and summer maize (WW-SUM) in the North China Plain (NCP) consumes a large amount of water and chemical fertilizer, threatening the sustainable development of agriculture in this region. This study was based on a three-year field experiment of different cropping systems (2H1Y-two harvests in one year; 3H2Y-three harvests in two years; and 1H1Y-one harvest in one year). The 2H1Y system had three irrigation-fertilization practices (FP-farmer's practice; RI-reduced input; and WQ-Wuqiao pattern in Wuqiao County, Hebei Province). A soil-crop system model (WHCNS-soil water heat carbon nitrogen simulator) was used to quantify the effects of different cropping systems on water and nitrogen use efficiencies (WUE and NUE, respectively), and to explore the trade-offs between crop yields and environmental impacts. The results showed that annual yield, water consumption, and the WUE of 2H1Y were higher than those of the 3H2Y and 1H1Y systems. However, local precipitation during the period of crop growth could only meet 65%, 76%, and 91% of total water consumption for the 2H1Y, 3H2Y and 1H1Y systems, respectively. Nearly 65% of irrigation water (groundwater) was used in the period of wheat growth that contributed to almost 40% of the annual yield. Among the three patterns of the 2H1Y system, the order of the WUE was 2H1Y_RI > 2H1Y_WQ > 2H1Y_FP. Compared to 2H1Y_FP, the total fertilizer N application rates in 2H1Y_WQ, 2H1Y_RI, and 3H2Y were reduced by 25%, 65%, and 74%, respectively. The 3H2Y system had the highest NUE of 34.3 kg kg-1, 54% greater than the 2H1Y_FP system (22.2 kg kg-1). Moreover, the 3H2Y system obviously reduced nitrate leaching and gaseous N loss when compared with the other two systems. The order of total N loss of different cropping systems was 2H1Y (261 kg N ha-1) > 1H1Y (78 kg N ha-1) > 3H2Y (70 kg N ha-1). Considering the agronomic and environmental effects as well as economic benefits, the 3H2Y cropping system with optimal irrigation and fertilization would be a promising cropping system in the NCP that could achieve the balance between crop yield and the sustainable use of groundwater and N fertilizer.

California’s groundwater overdraft: An environmental Ponzi scheme?

Groundwater levels have been decreasing in most agricultural areas, motivating research to find optimal solutions to balance socio-economical and environmental demands. Traditionally, groundwater optimization aims at long-term profit maximization, while accounting for the extraction costs. Following this approach, we find exploitation protocols characterized by pumping rates that slowly decrease in time toward a long-term sustainable value. However, the comparison of the model prediction with water extraction data for the period 1985–2021 from Kern County in California points out the inconsistencies between real management and long-term optimal behavior. Rather, the observed trajectory resembles those obtained by finite-time optimization horizons, which provide short-term high profits by over-drafting, while leading to long-term dilapidation of the capital and the exhaustion of the aquifer. Such myopic planning results in a Ponzi scheme for groundwater extraction. Like the infamous fraudulent scheme, ‘more-than-optimal’ profits are achievable by excessive short-term consumption by the early investors (the past and current aquifer exploiters), leaving the later comers (the future generations) with an impossible cost to sustain. Including the environmental costs of aquifer over-exploitation, the myopic nature of human planning can be corrected and reconciled with a more sustainable use of groundwater.

Determinants of water use saving behaviour toward sustainable groundwater management

Promoting GW saving behaviour is one of the strategies to support sustainable groundwater use and management and climate change adaptation. However, few studies paid attention to GW saving behaviours. To address this, we surveyed GW users (N = 338) to investigate factors influencing current GW saving attitudes and how GW saving behaviour is shaped in the community through the theory of planned behaviour (TPB). Participants were asked about the perception of their GW saving and water saving intentional behaviour. The probit regression use deployed explore factors influencing water users’ perception of GW saving. Structural Equation Model (SEM) was also used to construct the TPB variables to investigate psychological factors influencing GW saving intention behaviour. The findings show water users in the agricultural sector (β = −0.98, p = 0.01) are negative with GW saving bahavior. Changing to the users in the agricultural sector, the self-perception of GW saving tends to decrease in z-score by 0.98 at a statistical significance level. Awareness of GW extraction impacts (β = 0.89, p = 0.002), GW adequate knowledge and information (β = 1.16, p = 0.015) and GW tariff (β = 0.78, p = 0.02) have strongly influenced GW saving behaviour. The GW saving intentional behaviour has been influenced by subjective norms (β = 0.52, p < 0.001) and perceived behavioral control (β = 0.21, p < 0.001). Our findings suggest that GW policy options should pay attention to GW tariff application, awareness raising about GW impacts, GW knowledge dissemination to control GW abstraction in the community and enhance GW water saving attitude and behaviour in the community. The study also appeals to the engagement of local community in water governance to increase the social pressures on water-saving changing behaviors.

Analyzing past and future trends in Pakistan's groundwater irrigation development: implications for environmental sustainability and food security.

Since the last four decades, groundwater irrigation has played a critical role in improving crop production and rural livelihoods. However, the flawed policies have allowed farmers to install private tube wells relentlessly, resulting in a slew of water quality and environmental issues. This study aims to investigate the key trends in temporal development of groundwater irrigation and its consequences in Pakistan. The dataset, which spanned 38years (1981 to 2018), included variables such as the number of tube wells, wheat area and production, farm size, total cultivated area, and total irrigated area in Punjab province. Our results show that, while the number of government-installed tube wells has decreased over time, the number of private tube wells has increased by 579% since 1981. About 85% of these privately owned tube wells are diesel tube wells, while the remaining 15% are electric tube wells. The ARDL regression results show that groundwater development, as a result of growth in private tube wells, has significantly aided wheat production in both the short and long run. However, the results of ARIMA model show that, in the absence of any regulatory mechanism to limit private tube well growth, the number of private tube wells in Punjab will increase by 43% over the next two decades, potentially jeopardizing the country's groundwater sustainability and food security. To ensure the sustainability of groundwater use, farmers' incomes, and the food security of the population, there is an urgent need to devise policy options to limit the growth of probate tube wells in the province. In addition, the new regulations should consider the equity implications and the economic shock to poor farms and households.

Application of analytical hierarchical process, multi-influencing factor, and geospatial techniques for groundwater potential zonation in a semi-arid region of western India

Groundwater resources are alarmingly depleting due to over-exploitation and significant climate changes over time. Therefore, demarcation of groundwater potential zones is essential for addressing the needs of various industries in semi-arid area. Depleting groundwater resources, topography, aquifer features and climatic factors make it necessary to demarcate ground water potential zones in semiarid region of Rajasthan. The Analytical Hierarchy Process (AHP), Geographic Information System (GIS), and Multi Influence Factor (MIF) were used to determine the groundwater potential zones (GWPZs) in the semi-arid region of Jaipur, located in western Rajasthan. In present study, ten influential factors were employed i.e., geomorphology, land use/land cover (LULC), drainage density, rainfall, topographic wetness index (TWI), soil texture, slope, roughness, topographic position index (TPI) and curvature. In AHP technique, the pairwise comparison matrix was generated, and weightages were given to each thematic layer while for MIF, a proposed score for each layer was computed from the aggregate weight of major and minor effects. The GWPZ map generated by AHP technique was categorised into three parts: high, moderate and poor potential zones, covering 13%, 50.7% and 36.3% of the district. While, the GWPZ map produced with the MIF technique was also divided into the same poor, moderate, and high categories, encompassing 35.3, 44.1, and 20.6% of the district, respectively. The results of AHP and MIF techniques were then cross-validated with well depth data obtained from CGWB report, 2019–20. The receiver operating characteristics (ROC) were plotted and the findings shows that the Area under the Curve (AUC) was 79% and 76% for AHP and MIF, respectively which is considered as moderate to high in predictive precision. The study would be helpful in locating drilling sites for groundwater exploration and developing sustainable groundwater and land use policies.

A Framework for Sustainable Groundwater Management

This manuscript aims to present the framework for the development of a four-stage tool for sustainable groundwater management as one of the highly interactive three-day workshop products. The four stages in the tool are (1) representing the target system, (2) description of the target system using components of DPSIR framework (drivers, pressures, state, impact, responses), (3) development of causal chains/loops, and (4) identifying knowledge gaps and articulating next steps. The tool is an output from the two-day Indo-US bilateral workshop on "Integrated Hydrochemical Modeling for Sustainable Development and Management of Water Supply Aquifers”. Four case studies from the invited talks, panel discussions, and breakout sessions were selected to demonstrate the developed four-stage framework to a coastal aquifer (India) and in high plains in Floridian, Piedmont, and Blueridge aquifers (United States of America). The developed tool can be practically used in the development of strategies for the sustainable use of groundwater in various regions around the world (e.g., planning/building/maintaining groundwater recharging structures). Continued work can result in establishing a center for excellence as well as developing a network project. The recommendations from the workshop were: (1) developing vulnerability analysis models for groundwater managers; (2) treatment and new ways of using low-quality groundwater; (3) adopting groundwater recharge; (4) mitigating pollutants getting into the aquifer; and (5) reducing groundwater use. This study provides a framework for future researchers to study the groundwater table related to the effectiveness of water recharging structures, developing a quantitative model from the framework. Finally, recommendations for a future study are more data collection on groundwater quality/recharge as well as enhancing outreach activities for sustainable groundwater management.

Appraisal of groundwater pollution risk by combining the fuzzy AHP and DRASTIC method in the Burdur Saline Lake Basin, SW Turkey.

To ensure sustainable groundwater management, water resources must be protected in terms of quantity and quality. In this context, it is important to reveal the potential of existing groundwater resources to be affected by environmental and/or geogenic pollutants. In the present study, groundwater vulnerability assessment was performed using DRASTIC model by fuzzy AHP and GIS integration for Burdur Saline Lake basin, SW Turkey. In addition, validation and sensitivity analyses were performed in the study. Weight and rating values assigned for DRASTIC parameters and sub-parameters were determined by fuzzy AHP method, and these values were used in GIS analyses. In the validation analysis of the obtained groundwater vulnerability map, NO3 ion was considered since the agricultural activities are intense in the study area. In addition, sensitivity analyses were performed to determine the most effective parameter. According to the obtained results, 26.43% of the study area was determined as the highly vulnerable areas, while 11.44 and 62.13% were moderate vulnerable and low vulnerable, respectively. Impact of the vadose zone, depth to water table, and net recharge parameters were determined as more effective than other parameters. The nitrate concentrations of the groundwater in the region confirm the vulnerability map obtained by the study. Therefore, it is recommended to take realistic and urgent protection measures aimed at sustainable use of groundwater in highly vulnerable areas.

Assessment of Seasonal Changes on the Carbon Cycle in the Critical Zone of a Surface Water (SW)–Groundwater (GW) System

Groundwater is a valuable source of water for human consumption, and its quality is a current issue worldwide. Understanding carbon and water cycling presents the basis of biogeochemical reactions occurring in the aquifer; therefore, understanding their interaction is imperative for sustainable water management. In the paper, this interaction was investigated within the complex surface water (SW)–groundwater (GW) system in the Varaždin region (Croatia) by using a multi-parameter approach: δ13CDIC values, carbon species (DIC, DOC), δ18O and δ2H values, geochemical indicators (T, pH, DO, EC), and δ13C measurements in solids. Both δ18O/δ2H and δ13CDIC were recognized as good indicators to differentiate shallow and deep GW. Transit time of water (TT) was evaluated as an important parameter in controlling carbon cycling within the SW–GW system. Shallow GW is characterized by shorter TT, seasonal changes in carbon species and δ13CDIC, and lower possibility of carbon capture in the system. Deep GW has longer TT without pronounced seasonal changes in carbon species and δ13CDIC. The conceptual model of the carbon cycle revealed major sources and sinks of CO2 in the study area. Our results suggest that GW acts as both source and sink for CO2, depending on the prevailing geochemical process. Surface waters are primarily a source of CO2, excluding the gravel pit, which acts primarily as a sink for CO2. Our study shows that the current SW–GW dynamics regulate carbon balance without having negative impacts on groundwater quality but also demonstrates that implementing carbon cycle in water management studies is of vital importance for sustainable use of groundwater.

Individual to collective adaptation through incremental change in Colorado groundwater governance

Designing adaptive institutions for achieving sustainable groundwater use is a central challenge to local and state governments. This challenge is exacerbated by the growing impacts and uncertainty of climate change on water resources. Calls to reform water governance systems are often made in the context of these challenges, and reform efforts increasingly emphasize the need for solutions that are locally designed and administered. Such reforms often require fundamental institutional change that is difficult to achieve amid the myriad forces that stabilize and reproduce existing institutional structures and functions. In practice, governance change is instead overwhelmingly incremental and tends to be punctuated by periods of adjustment in response to social or environmental shocks and disturbances. We present a comparative study of four major Colorado river basins and examine how each has evolved distinct arrangements of groundwater governance in response to regulatory and drought disturbances over the past century. We interrogate concepts of path-dependence and apply a historical lens to understand why locally designed institutions for self-regulation emerge in some Colorado groundwater basins but not in others. We uncover a pattern of collective action by groundwater users that first seeks to oppose state regulation, followed by acceptance and efforts to comply, and eventual attempts to get ahead of state regulation by enacting local institutions for self-regulation. We report these findings and discuss the insights they offer for understanding how adaptive natural resources institutions are shaped through time by the constraints and opportunities of path-dependence and local contexts.

Does water accounting support sustainable water management? A review

The business risks experienced by clean water companies include losses and decreased loyalty of water users. This risk occurs due to the absence of accountability, reliability, and transparency in sustainable clean water management. It can be overcome by implementing water accounting. This narrative review explains a sustainable water management model using a water accounting approach. The narrative review method consists of compilation, tabulation, comparison of research results, and summarizing. The literature review study collected articles from accredited journal sites (Sinta, Emerald, Science Direct). After searching for research keywords criteria, 29 articles were taken as samples. The results show that water accounting, in addition to reducing business risk for clean water service providers, also supports sustainable water management. Water accounting components such as gross inflow, net inflow, available water, water depletion, and outflow provide transparent and accountable information. The components of water accounting can analyze water use, scarcity, and productivity to predict the need for clean water because the amount of water discharge produced and used in one day can be known with certainty. Management and community commitment are needed to realize sustainable groundwater use conservation to ensure that the community enjoys the long-term supply of clean water.

Research into the Optimal Regulation of the Groundwater Table and Quality in the Southern Plain of Beijing Using Geographic Information Systems Data and Machine Learning Algorithms

The purpose of this paper is to provide new ideas and methods for the sustainable use of groundwater in areas with serious groundwater overexploitation and serious groundwater pollution. Geographic information systems (GIS) were combined with machine learning algorithms, water resources optimization technology, and groundwater numerical simulation to optimize the regulation of the groundwater table and quality beneath the Daxing District in the southern plain of Beijing. By collecting local consumption and supply data and observations of the groundwater table and quality in the connected aquifer beneath Daxing for the years 2006–2020, the corresponding water demands and groundwater impact were extrapolated for the years 2021–2025 based on the basis of the existing development model. Through the combination of GIS and machine learning algorithms, the NO3-N concentration of local groundwater monitoring points in wet years, normal years, and dry years were predicted. With respect to NO3-N pollution, three new groundwater exploitation regimes were devised, which we numbered 1 to 3. The optimal allocation of water resources was then calculated for wet year, typical year, and dry year scenarios for the year 2025. By comparing the water shortage, groundwater utilization rate, and NO3-N pollution under the new groundwater exploitation regimes, the optimal groundwater exploitation mode for the three different types of hydrological year was determined. The results indicate that NO3-N pollution was greatly reduced after the adoption of the optimal regimes and that the groundwater table demonstrated rapid recovery. These results can be of great help in realizing the management, supervision, and regulation of groundwater by combining GIS with machine learning algorithms.

Geospatial analysis of groundwater quality using GIS: A case study of Ahafo Kenyasi, Ghana

The exploitation and sustainable use of groundwater has received much attention with the sudden decline in quantity and quality of surface water. Knowledge on the current status of the physico-chemical parameters of groundwater becomes important in ensuring the sustainable use of the resource. This study used Geographic Information System (GIS) to assess groundwater quality in Ahafo-Kenyasi with particular focus on determining the spatial distribution of groundwater quality parameters and also produce groundwater quality map of the area. Physico-chemical analyses of groundwater quality parameters were made after collection of water samples from 24 community boreholes. The results of analysis carried out showed the following concentration ranges: pH (5.12-6.54), EC (71.6-952μS/cm), TDS (35.08-465.59mg/l), Turbidity (0-6.25NTU), Ammonia (0.01-0.61mg/l), Nitrate (0.1-4.12mg/l), Sulphate (1-65.5mg/l). All the samples analysed were above the guidelines set by World Health Organization (WHO, 2011) except for pH and Turbidity. Spatial distribution maps of the individual water quality parameters were developed using kriging interpolation technique and accepted based on the prediction performances of Stable, Exponential, K-Bessel semivariogram models. Overall water quality of the study area was assessed using Water Quality Index (WQI). The results showed that groundwater quality in the area decreases from north-western to south-eastern. However, groundwater from Ahafo-Kenyasi is good for domestic purposes.

Groundwater metabolome responds to recharge in fractured sedimentary strata

Understanding the sources, structure and fate of dissolved organic matter (DOM) in groundwater is paramount for the protection and sustainable use of this vital resource. On its passage through the Critical Zone, DOM is subject to biogeochemical conversions. Therefore, it carries valuable cross-habitat information for monitoring and predicting the stability of groundwater ecosystem services and assessing these ecosystems’ response to fluctuations caused by external impacts such as climatic extremes. Challenges arise from insufficient knowledge on groundwater metabolite composition and dynamics due to a lack of consistent analytical approaches for long-term monitoring. Our study establishes groundwater metabolomics to decipher the complex biogeochemical transport and conversion of DOM. We explore fractured sedimentary bedrock along a hillslope recharge area by a 5-year untargeted metabolomics monitoring of oxic perched and anoxic phreatic groundwater. A summer with extremely high temperatures and low precipitation was included in the monitoring. Water was accessed by a monitoring well-transect and regularly collected for liquid chromatography-mass spectrometry (LC-MS) investigation. Dimension reduction of the resulting complex data set by principal component analysis revealed that metabolome dissimilarities between distant wells coincide with transient cross-stratal flow indicated by groundwater levels. Time series of the groundwater metabolome data provides detailed insights into subsurface responses to recharge dynamics. We demonstrate that dissimilarity variability between groundwater bodies with contrasting aquifer properties coincides with recharge dynamics. This includes groundwater high- and lowstands as well as recharge and recession phases. Our monitoring approach allows to survey groundwater ecosystems even under extreme conditions. Notably, the metabolome was highly variable lacking seasonal patterns and did not segregate by geographical location of sampling wells, thus ruling out vegetation or (agricultural) land use as a primary driving factor. Patterns that emerge from metabolomics monitoring give insight into subsurface ecosystem functioning and water quality evolution, essential for sustainable groundwater use and climate change-adapted management.

Alternative cropping systems and optimized management practices for saving groundwater and enhancing economic and environmental sustainability

Rapid decline in groundwater table due to excessive withdrawal of water for irrigation has been posing a serious threat to sustainable agricultural production in hot arid region of India. Alternative cropping systems having low irrigation requirement have been proposed to resolve unsustainable groundwater use but trade-off with other dimensions such as yield, profitability, and environmental impacts is not well-documented. An integrated analysis of amount of groundwater use, productivity, profitability, resource-use efficiency (RUE), and environmental impacts of three cluster bean-based cropping systems [conventional cluster bean (Cyamopsis tetragonoloba)–wheat (Triticum aestivum) (CB–W), and two alternative cropping systems, namely cluster bean-Indian mustard (Brassica juncea) (CB–IM) and cluster bean–blond psyllium (Plantago ovata) (CB–BP)] under different soil management practices [two tillage types, i.e., conventional (CT), and deep tillage (DT); and three farmyard manure (FYM) application rates, i.e., 0, 5, 10 Mg ha-1] was carried out. Based on a three-year field experiment, compared to conventional CB–W, alternative cropping systems produced 28.6–47.4 % lower seed yield, but enhanced economic returns (7.6–31.1 %), while reduced amount of irrigation (− 27.9 to − 37.2 %), energy (− 22.4 to − 37.0 %), and nutrient (− 17.4 to − 46.1 %) used, global warming potential (− 20.2 to − 45.9 %) and greenhouse gas intensity (− 27.3 to − 57.7 %). Alternative cropping systems saved 1.87–2.50 × 103 m3 per year per hectare of groundwater than conventional cropping systems. Soil management practices influenced agro-economic and environmental dimensions of cropping systems. Deep tillage (DT) enhanced yield (14.0 %), economic profit (18.8 %), RUE (13.2 %, 13.8 % and 8.5 % for nutrient, water and energy use efficiency, respectively). Addition of FYM increased yield (up to 23.0 %), economic net return (up to 21.8 %), RUE (up to 22.7 %, 16.5 %, 91.0 % in water, energy and nutrient use efficiency), and reduced global warming potential (up to − 7.9 %). The CB-BP cropping system with DT and FYM addition offered the best balance of yield, profit, saving of irrigation water, energy and nutrient, while minimizing GWP. This study provides empirical evidence of the opportunities for alternative cropping systems which balance the multiple objectives of sustainable groundwater use, farmer profitability and environmental sustainability for arid region of India. The results have direct implications for sustainable utilization of underground water for similar regions of the world facing water shortage.

Irrigation water demand and elasticities: a case study of the High Plains aquifer

The agriculture of the Texas High Plains (THP) region is primarily dependent on groundwater irrigation. Changing weather patterns along with competing demands for water resources and other anthropogenic effects have dramatically increased withdrawals from the Ogallala aquifer. In addition to on-farm changes, policy tools based on off-farm mechanisms are equally indispensable in addressing sustainable groundwater use in the THP. One such policy tool is water pricing using estimates of price elasticity of irrigation water demand. This paper estimates the elasticity of irrigation water demand in the THP and assesses the influence of water price on major inputs used in dominant irrigated crops such as corn and cotton. Using the translog profit function on an annual county-level dataset of THP crop production, spanning 23 years (1998–2020), we find that irrigation water demand is price elastic for cotton (η = – 1.58) but inelastic for corn (η = – 0.81). Our findings suggest that a non-uniform pricing policy could be a useful tool to promote the efficient use of groundwater for irrigation.

FRACTURING AND PERMEABILITY OF CRYSTAL ROCKS AND THEIR FRACTURE ZONES, HYDROGEOLOGICAL ASPECT

Fractured rock aquifers are regarded as of particular scientific and practical interest because of their importance for underground water supply, energy storage and safety radioactive waste disposal. The study of fissure waters of crystalline rocks in the context of global warming to address issues of drinking water supply is highly relevant today. It has potential practical importance for the future.The sustainable use of groundwater in fractured rock aquifers requires a detailed knowledge of their hydraulic properties. The complexity of hydrogeological conditions in massive fractured rocks results from uncertainties about the configuration of the fractures, while the potential for groundwater movement in such rocks is primarily determined by their permeability and, consequently, hydraulic conductivity. Fractures (fracture networks) have different permeability properties, which is one of the key parameters required for understanding and predicting fluid and water flow. This paper reviews and analyses the results of global studies of fracturing and permeability of crystalline rock massifs and the fault zones occurring in them. Since the study of permeability of crystalline rocks concerns many disciplines — including structural geology, tectonophysics, petrophysics, hydrogeology, and hydrology — this review highlights information about the distribution of groundwater in fractured crystalline rocks in the context of their potential exploitation. This study consists of two parts: generalization of research results concerning fracturing and permeability of crystalline rocks, and particularities of structure of fracture zones in crystalline rocks and of the presence of groundwater in them. Based on this review of the structure and development of fracture zones (including their evolution under the influence of weathering and other secondary processes), recommendations are given for using tectonophysical reconstructions to improve hydrogeological field works and mathematical modeling.