Geospatial irrigation suitability assessment of groundwater: A case study from Thar desert of India

The Sundarban region—located from the Hooghly River in India's state of West Bengal to the Baleswar River in Bangladesh—renowned for its distinctive ecosystem and agricultural techniques, heavily depends on groundwater for irrigation purposes. However, concerns arise regarding the suitability of groundwater for sustainable agriculture in this vulnerable coastal zone. This systematic review aims to comprehensively evaluate the quality and appropriateness of groundwater and surface water for irrigation in the Sundarban region. By extensively searching scientific databases and relevant literature, we identified eighteen studies meeting our inclusion criteria. These studies encompassed hydrological, hydrochemical, and agronomic parameters, facilitating a thorough assessment of groundwater quality and its potential impacts on crop productivity. The review evaluates key parameters such as total hardness, residual sodium carbonate, potential salinity, permeability index, Kelly's ratio, sodium absorption ratio, corrosivity ratio, and chloroalkaline indices. The results revealed that irrigation water displays an alkaline nature, and both surface water and groundwater were unsuitable for irrigation due to exceedingly high-quality parameters beyond the standard limits. Nevertheless, groundwater exhibited favorable physiochemical properties. The review identifies critical research gaps and proposes future directions to enhance the understanding of groundwater suitability for irrigation in the Sundarban region. The findings emphasize the necessity of a multidisciplinary approach to ensure sustainable agricultural practices and safeguard the delicate ecosystem of the Sundarban region.

A total of seventy irrigation water samples were collected from Leh, Ladakh, India, to determine their hydrochemistry profile and water quality for irrigation purposes. Water quality indices such as total hardness (TH), residual sodium carbonate (RSC), potential salinity (PS), permeability index (PI), Kelly's ratio (KR), sodium absorption ratio (SAR), corrosivity ratio (CR), and chloroalkaline indices (CAI) were measured. The Piper diagram, Durov's diagram, and United States Salinity Laboratory (USSL) diagram were drawn to determine the water types, ion exchange processes, and rock–soil–water interaction. The findings indicated that the hydrochemical characteristics of irrigation water are naturally alkaline. Furthermore, water quality parameters revealed that the study area’s surface water is suitable for irrigation purposes, despite relatively high TH and MH levels. The level of CR indicated that water should not be transported using metal pipes. The CAI and Durov's plot indicated direct ionic exchange processes controlling water chemistry. Additionally, this irrigation water is mainly dominated by the Ca2+–Cl−–SO42−, Na+–K+–CaCO3 + HCO3−, and Na+–K+–Cl− type, which indicates silicate rock weathering along with some anthropogenic input. The USSL salinity diagram indicated a medium salinity and low Na hazard. Hence, it is concluded that the rock weathering cycle is the natural source of all the cations and anions, and these ions pass directly from water to rock and vis-à-vis, along with some input of anthropogenic activity.

Regional study on the impact of variations in input rainfall over groundwater quality and its suitability for utilitarian purposes is essential for its extraction and management. Water chemistry from 456 observations wells for 2007–2011 period in hard rock Basaltic terrain of Upper Godavari basin is supported with 8 field samples (in 2014) in this analysis. Based on mean annual rainfall (MAR), four narrow climatic zones are identified in the basin, defined as “humid” (MAR > 1600 mm), “sub-humid” (1600–1000 mm), “semi-arid” (1000–600 mm), and “arid” (MAR 600 mg/L) and not acceptable for drinking. Suitability of groundwater for irrigation is studied using sodium percentage (Na %), Wilcox diagram, sodium absorption ratio (SAR), US salinity diagram, residual sodium carbonate (RSC), permeability index (PI), Kelly’s ratio (KR), ancd magnesium absorption ratio (MgAR). Na % in four zones is 75% (class 1). KR varied from 0.05 to 12.81, with 70–80% of the area having KR < 1. MgAR ratio ranged from 67% to 96%, with sub-humid, humid zones having higher Mg concentrations (increased salinity). Thus, 90% of the samples indicated non-alkaline water with 1% of normal alkalinity. Hence, the current study systematically analyzed the effect of precipitation and geology on groundwater quality and on its usability for various purposes. This stepwise procedure categorized the regions, and the same can be adopted for any regional hydrogeochemical studies.

Evaluation of the water suitability for irrigation purposes using conventional approaches is generally expensive because it requires several parameters, particularly in developing countries. Therefore, developing accurate and reliable models may be valuable to overcome this issue in the management of the water used in agriculture. To achieve this purpose, 8 Machine Learning (ML) models namely: Artificial Neural Network (ANN), Multiple Linear Regression (MLR), Decision Tree, Random Forest (RF), Support Vector Regression (SVR), k-Nearest Neighbour (kNN), Stochastic Gradient Descent (SGD) and Adaptive Boosting (AdaBoost) have been developed and validated for predicting of 10 Irrigation Water Quality (IWQ) parameters such as Sodium absorption ratio (SAR), adjusted SARa, Exchangeable Sodium Percentage (ESP), percentage of Sodium (%Na), Residual Sodium Carbonate (RSC), Permeability Index (PI), Kelly Ratio (KR), Chloride Cl−, Magnesium Absorption Ratio (MAR), and TDS dissolved in water surface of Bouregreg watershed in Morocco using electrical conductivity (EC) and pH as input variables. 300 samples are analysed at 9 monitoring stations across four main rivers, processed and selected to train and validate the models. The results have revealed that, except for SVR and k-NN models and MAR and PI parameters, all other models are highly accurate in predicting the other parameters with coefficients of correlations (r) with ranges of [0.56, 0.99], and [0.64, 0.99] for training and validation processes sequentially. Furthermore, this study attempts to generalize the 6 ML models developed and validated to the Cherrate and Nfifikh watersheds that are different from Bouregreg watershed. The results of the generalization attempt have shown that the ML models are fairly generalized for TDS, SAR, and SARa parameters to Cherrate watershed and for TDS, chloride, ESP and %Na parameter for Nfifikh watershed. The results of this study have also demonstrated that the machine learning models are efficient tools for accurately predicting the quality of irrigation water by only using the parameters that can be directly measured in a short time. Consequently, the implementation of the automated sensor technologies coupled with ML models improve the control of water quality and will help the farmers to manage the irrigation water quality.

The groundwater chemistry of a region is sensitive to climate change and to change of agricultural practice of the surrounding region. The water quality is also largely governed by the litho hydrological character of the region. Hence monitoring the hydrochemistry of the groundwater with respect to climate change is vital for detecting its suitability for irrigation of cropland and industrial use. The present study area Athgarh basin, belongs to upper Gondwana has a varied lithology. The regional scale data can be statistically related to climate change. Moreover, seasonal variation of water quality has been monitored after systematic collection of groundwater samples and their methodical physicochemical analysis. 75 water samples were collected during pre-monsoon, monsoon and post-monsoon period of 2015-2016. The quality assessment is made through the estimation of physicochemical parameters, cations and anions. Based on these analyses, the irrigational parameters like salinity hazard, sodium absorption ratio (SAR), sodium%, residual sodium carbonate (RSC), potential soil salinity (PS), magnesium ratio (MR), corrosivity ratio (CR) and permeability index (PI) were calculated to determine the suitability of groundwater for irrigational and industrial purpose. The groundwater falling under (Doneen’s) class-II is almost good for irrigation purpose whereas groundwater falling under class-III indicates poor water quality. The groundwater samples are excellent to good as per Wilcox diagram. From Gibb’s diagrams, it can be established that the groundwater of the study area is mainly dominated by the lithology of aquifer of the concerned region.Various classifications show that present status of groundwater is suitable for irrigation purpose, except few locations, with a caution that it may deteriorate in near future

The present study aims at analyzing groundwater quantity and quality simultaneously to identify its availability and suitability for irrigation. Various water quality indices were used to assess (i) origin of the groundwater sources (Gibbs diagram); (ii) salinity, alkalinity, and sodium hazard (sodium adsorption ratio, exchangeable sodium percentage, Kelly's ratio, US Salinity Laboratory diagram, Wilcox diagram); (iii) magnesium hazard (magnesium absorption ratio); (iv) carbonate and bicarbonate hazard (residual sodium carbonate); (v) hydro-chemical facie and evaluation (Piper diagram and Expanded Durov diagram); and (vi) statistical relationship among the variables, sample sites, and spatiotemporal grouping (principal component analysis and cluster analysis). The overall objective is to quantify the irrigation suitability of groundwater reserves. Gibb's diagram suggests that the groundwater quality is mainly controlled by rock-water interaction. Piper trilinear showed the presence of various types of hydro-chemical facies such as Ca-Mg-HCO3, mixed, and sodium bicarbonate. The expanded Durov diagram revealed the hydro-chemical evolution, grouping, and areal distribution of the groundwater samples. USSL diagram, Wilcox diagram, Kelly's ratio, magnesium hazard, and permeability index suggest that the groundwater quality is suitable for irrigation. Kaiser-Meyer-Olkin (KMO) and Bartlett's tests confirmed the applicability of principal component analysis (PCA), which indicates that groundwater quality is controlled by rock-water interaction mainly. It also suggests that the groundwater has carbonate dissolution, which indicates the groundwater's hardness increased. Cluster analysis (CA) from the year 2000 to 2010 shows 4 to 8 groups present within the study area. Irrigation water quality suitability map and predicted groundwater potential zone map together act as a master tool for deciding tube well location, pumping schedule, and crop planning for the sustainability of the agriculture eco-system in the study area. The implementation of the aforementioned activities in the study area will further stop the advancement of the seawater intrusion front. The methodology shows the potential applicability for similar coastal groundwater basins worldwide with or without modification.

Twenty (20) shallow wells were sampled during the dry season (October 2015) from the Guenniche plain (Northern Tunisia) and examined for their suitability for irrigation. The physicochemical analysis results are used to estimate 10 indexes: the sodium absorption ratio (SAR), percentage of sodium (Na %), residual sodium carbonate (RSC), permeability index (PI), magnesium ratio (MR), residual sodium bicarbonate (SBC), salinity hazard (SH), potential salinity (PS), soluble sodium percentage (SSP), and Kelley’s Ratio (KR). The majority of the criteria (SAR, %Na, RSC, PI, KR, and RSBC) indicate that 100% of the studied water is ‘permissible’ for irrigation. But the rest of criteria show different results. The PS results classify 90% of the samples into the “moderate to satisfactory” category due to high chloride (Cl−) values (average Cl− value 589 mg.l−1) and SH index shows that 65% of groundwater samples are falling in the ‘doubtful’ category. The use of the IDW method for the spatial distribution of the criteria points out that central area and East of Guenniche plain are characterized by the low groundwater quality for irrigation purposes. The improvement of the efficiency of irrigation fertilization in those areas’ practices would improve the water quality of the Guenniche shallow aquifer.KeywordsGuenniche plainShallow groundwater wellsAgricultureIrrigation water quality criteria

Land exploitation for mining sector may leave a series of environmental impacts on our ecosystem if not appropriately managed. Therefore, the present study attempts to evaluate the various environmental aspects due to abandoned metal mining including former iron ore, bauxite, and tin mining lands in view of its hydrogeochemical behavior. Mine-impacted waters and sediments were ascertained from former mining ponds, mine tailings, and impacted streams for interpretation of aqueous and sediment geochemistry, major and trace elements, hydrochemical facies, chemical weathering rate and CO2 consumption, and water quality classification. Results indicated that the environmental impact of the long-abandoned iron ore mine was still evident with some high concentration of metals and acidic pH. Higher concentrations of Fe and Mn in water were noticeable in some areas while other trace elements (Pb, Zn, As, Cd, Cr, and Cu) were found below the recommended guideline values. Sediment quality reflected the trend of water quality variables mainly associated with metal(loid) elements, resulting in potential ecological risk, classified as having low to moderate risk. There were variations in terms of hydrochemical facies of the waters suggesting the influence of minerals in water. The chemical weathering rate suggests that contribution of carbonate mineral weathering was more important (up to 60%) than silicate weathering. The resulting CO2 consumption by mineral weathering was estimated to be in the range of 1.7-9.8 × 107 mol/year (former bauxite and tin mining areas can act as temporary sinks for CO2). Water quality classifications according to several chemical indices (Kelly's ratio, sodium absorption ratio, soluble sodium percentage, residual sodium carbonate, magnesium absorption ratio, and permeability index) were also discussed in regards to mine water reuse for irrigation purpose. The findings suggest that a holistic approach that integrates all important hydrogeochemical aspects is essential for a thorough evaluation of the implication of medium- to long-term mining exploitation on its surrounding ecosystems. This would be beneficial in light of restoration potential of degraded mining land so as for future mitigation strategies in the mining sector.

Saltwater intrusion in the coastal areas of Bangladesh is a prevalent phenomenon. However, it is not conducive to activities such as irrigation, navigation, fish spawning and shelter, and industrial usage. The present study analyzed 45 water samples collected from 15 locations in coastal areas during three seasons: monsoon, pre-monsoon, and post-monsoon. The aim was to comprehend the seasonal variation in physicochemical parameters, including water temperature, pH, electrical conductivity (EC), salinity, total dissolved solids (TDS), hardness, and concentrations of Na+, K+, Mg2+, Ca2+, Fe2+, HCO3-, PO43-, SO42-, and Cl-. Additionally, parameters essential for agriculture, such as soluble sodium percentage (SSP), sodium absorption ratio (SAR), magnesium absorption ratio (MAR), residual sodium carbonate (RSC), Kelly's ratio (KR), and permeability index (PI), were examined. Their respective values were found to be 63%, 16.83 mg/L, 34.92 mg/L, 145.44 mg/L, 1.28 mg/L, and 89.29%. The integrated water quality index was determined using entropy theory and principal component analysis (PCA). The resulting entropy water quality index (EWQI) and SAR of 49.56% and 63%, respectively, indicated that the samples are suitable for drinking but unsuitable for irrigation. These findings can assist policymakers in implementing the Bangladesh Deltaplan-2100, focusing on sustainable land management, fish cultivation, agricultural production, environmental preservation, water resource management, and environmental protection in the deltaic areas of Bangladesh. This research contributes to a deeper understanding of seasonal variations in the hydrochemistry and water quality of coastal rivers, aiding in the comprehension of salinity intrusion origins, mechanisms, and causes.

The hydrogeochemical evaluation of groundwater resources and their suitability for agricultural and industrial uses in an arid area of Iran

The purpose of this research is the zoning of groundwater quality for agriculture usages in the Eyvanakey plain, conjugating Interpolation methods by Geographic Information System (GIS) and selection of the best weights in Analytical Hierarchy Process (AHP). Achieving this aim, groundwater quality data from 19 wells in Eyvanakey plain were used. First, raster maps of the study area was prepared, using Inverse Distance Weighted (IDW) method, containing the Sodium Absorption Ratio (SAR), Permeability Index (PI), Kelley Ratio (KR), Magnesium Absorption Ratio (MAR), Residual Sodium Carbonate (RSC), Sodium solubility Percentage (SSP), Electrical Conductivity (EC) and Total Hardness (TH). Then, the final weights of parameters were determined by Hierarchical Analysis Process and pairwise matrix. Finally, the map of groundwater qualitative potential for agricultural purposes, prepared, using map overlaying and final weights of the parameters, applying in GIS. Results showed, the groundwater quality for agriculture uses in center and south is bad whereas at east is moderate and at west it was good.

Groundwater is an essential natural resource for mankind. Due to various geogenic and anthropogenic causes, groundwater quality has raised serious concern over the years. In this study, groundwater quality was evaluated for its suitability for irrigation in the Jorhat and Golaghat Districts of Assam, India. A total of 100 groundwater samples were collected from shallow aquifers (< 35m) from different locations during the pre-monsoon season (March-April 2022). Groundwater in the study area is slightly alkaline in nature (mean pH value of 7.44). The average cations and anions chemistry are in the order of Na+ > Ca2+ > Mg2+ > K+ and HCO3- > Cl- > SO42- > CO32-, respectively. Ca-Mg-HCO3 followed by Na-Ca-HCO3-Cl are the primary water types in the study area. Pearson's correlation matrix showed a positive correlation between TDS and EC (r = 0.78) and sodium showed a positive correlation with TDS and bicarbonate (r = 0.62 and r = 0.65), respectively. Gibbs plot indicated that rock-water interaction is the dominant factor that controls the chemistry of the groundwater of the area. Irrigation parameters like Sodium Absorption Ratio (SAR), Permeability Index (PI), Magnesium Absorption Ratio (MAR), Kelly's Ratio (KR), and Irrigation Water Quality Index (IWQI) indicated that groundwater is overall suitable for irrigation. USSL diagram illustrated that most of the samples fell into the C2 (medium salinity) and S1 (low sodium hazard) categories. Wilcox plot showed the samples fell in excellent to good categories indicating fitness of groundwater for irrigation in the area.

A diagnosis of the groundwater quality of 70 wells sampled during two climatic regimes (dry and raining seasons) from a semiarid area in Rajasthan, India, had been carried out using standard methods. Analysis of the results for various hydrochemical parameters wherein the geological units are alluvium, quartzite and granite gneisses showed that all the parameters did not fall within the World Health Organisation’s acceptable limits for irrigation and drinking water purposes. The order of major cations and anions obtained during the dry and raining seasons are Na+ ˃ Mg2+ ˃ Ca2+ ˃ K+ and Cl−˃ HCO3 − ˃ SO4 2−˃ CO3 −> F− ˃ NO3 −, respectively. A maximum value of nitrate of 491.6 mg/l has been examined and its contamination is due to discriminated highly impacted groundwater samples by agricultural activity and small-scale urbanization. Fluoride (F−) concentration is 6.50 mg/l as a maximum value, whereas values in about 26 % of the samples are more than the permissible limit (1.5 mg/l) for drinking water. The cumulative probability distributions of the selected ions show two individual intersection points with three diverse segments, considered as regional threshold values and highly impacted threshold values for differentiating the samples with the effects of geogenic, anthropogenic and saline water mixing. The first threshold values indicate the background hydrochemical constituents in the study area. The second threshold value of 732 mg/l for bicarbonate indicates that sandy aquifer is being dissolved during wet period, whereas NO3 − concentration of more than the initial threshold value (=75 mg/l) indicates discriminated highly impacted groundwater samples by agricultural activity and urbanization in dry season. Various parameters such as soluble sodium percentage (SSP), salinity (electrical conductivity (EC)), sodium adsorption ratio (SAR), residual sodium carbonate (RSC), Kelley’s ratio (KR), permeability index (PI), residual sodium bicarbonate (RSB) and magnesium absorption ratio (MAR) for the well samples show that, overall, 46 % of groundwater samples are not suitable for irrigation. Further, chloro-alkaline indices (CAIs) were used for distinguishing regional recharge and discharge zones whereas corrosivity ratio (CR) utilized for demarcating areas to use metallic pipes for groundwater supply. In general, groundwater quality is mainly controlled by the chemical weathering of rock-forming minerals. The information obtained represents a base for future work that will help to assess the groundwater condition for periodical monitoring and managing the groundwater from further degradation.

This study evaluated the possibility of conjunctive use (CU) of shallow groundwater (SGW) and surface water for irrigation at the Wonji Shoa Sugar Estate (WSSE) (Ethiopia). Irrigation suitability was investigated by taking 46 SGW samples from piezometers and hand‐dug wells. Many physicochemical parameters (Mg2+, Na+, Ca2+, K+, CO3−, SO42−, HCO3−, Cl−, TH, EC, TDS and pH) and other indices (MAR (magnesium adsorption ratio), SSP (soluble sodium percentage), SAR (sodium absorption ratio), RSC (residual sodium carbonate), KR (Kelly's ratio) and permeability index (PI)) were analysed following standard procedures. The salinity and infiltration problems of SGW were found to be none to moderate with no chloride and boron ion toxicity. The sodium ion toxicity problems are slight to moderate. The SGW is generally categorized under C3S1 (high salinity and low sodium hazard). However, a high value of SSP and RSC indicates a high possibility of occurrence of infiltration problems when using SGW. Hence, CU of SGW and surface water must be practised to minimize the potential problems of infiltration and salinization and their associated difficulties in soil and sugar cane productivity. Therefore, during CU planning, optimum irrigation scheduling that considers the in situ use of groundwater table must be practised. © 2019 John Wiley &amp; Sons, Ltd. © 2019 John Wiley &amp; Sons, Ltd.

Abstract: Integrated geoelectric and geochemical investigation were carried out in the Canning and adjoining areas to assess the prevailing groundwater conditions and chemical quality of groundwater. Geologically, the area is constituted of alluvial sediments of Quaternary age. Vertical electrical soundings (VES) in the area of investigation mostly show six layers consisting of top soil, saline water, clay layer, brackish water, clay layer and fresh-water bearing zone of appreciable thicknesses at depths of 137 to 182 meter at six locations and from 370 to 430 meter for other two locations under confined conditions. The result of VES studies significantly correspond with the borehole litholog and well log data. A litho-resistivity relationship is established for this area of investigation A Fence diagram is constructed to show the spatial variation of the sub-surface lithology and hydrological characteristics. Chemically the ground water is fresh and mixed cation and anion type as revealed from Piper-Trilinear diagram with TDS ranging from 699 to 1547 mg/l. The geochemical parameters like Total hardness (TH), Sodium absorption ratio (SAR), Soluble sodium percentage (SSP), Percentage of sodium (PS), Kelley’s ratio (KR), Residual sodium carbonate (RSC), Corrosivity ratio (CR), Gibbs ratios (GR), Chloro alkaline indices (CAI), Sea water contamination (SWC) are also calculated for examining the quality of groundwater in the area. The depth of occurrences of freshwater bearing ground water zones for drinking and irrigation purposes are occurring at depths from 137 meter to 430 meter in this area.