Water Quality Index Values Research Articles

Monitoring soil salinization and waterlogging in the northeastern Nile Delta linked to shallow saline groundwater and irrigation water quality.

Soil salinization and waterlogging are critical environmental issues affecting agricultural productivity and cultural heritage preservation, particularly in arid regions. This study investigated soil degradation processes in the archaeologically and agriculturally significant northeastern Nile Delta of Egypt. The objective was to assess the severity of soil degradation and identify key drivers related to water resources and soil characteristics to aid in the development of management strategies. The research employed a multi-faceted approach, including hydrochemical analyses (of groundwater, irrigation water, and soil), water quality indices calculations, statistical analyses, and satellite data. The results revealed high levels of soil salinization in the northern and central areas, with 64% of soil samples classified as strongly and very strongly saline. Soil chemistry indicated salinization sources linked to sodium chloride dominance. Satellite data from Sentinel-2 images and SRTM digital elevation data showed widespread severe waterlogging in the northern lowlands. The Irrigation Water Quality Index (IWQI) values indicated that 87.5% of irrigation water samples posed severe restrictions due to high salinity and sodium hazards, which were mismatched with the low soil permeability observed in 81% of the collected samples exhibiting clay texture and covering most of the study area. Furthermore, shallow groundwater at depths of 0.5-3m with high salinity was detected, where total dissolved solids exceeded 20,000mg/L, and Na-Cl water types prevailed, indicating saltwater intrusion. A strong positive correlation (r > 0.83) was found between shallow saline groundwater and soil salinity. The combination of poor irrigation water quality, shallow saline groundwater tables, and low-permeability soils created a synergistic effect that severely compromised soil health and agricultural productivity. It also posed severe risks to the structural integrity of archaeological sites and buried artifacts through accelerated physical and chemical weathering processes. This necessitates an urgent mitigation strategy to combat soil degradation in this critical area.

Geoenvironmental determinants influencing chronic kidney disease of unknown etiology in the dry zone of Sri Lanka: a study based on a cohort of at-risk communities.

Chronic kidney disease of unknown origin (CKDu) has emerged as a serious health risk for farming communities in remote semi-arid lowland regions of Sri Lanka, with geoenvironmental factors widely believed to be associated with the etiology. Although numerous case-control studies have been carried out to determine the causes of CKDu, none have been conducted in at-risk communities. The main objective of this study is to identify the potential geo-environmental risk factors associated with the at-risk community in the Wilgamuwa region, a CKDu endemic area in Sri Lanka. The study collected and analyzed 92 water sources currently or previously used in the study area for major cations, anions, and trace elements, mainly As, Cd, Pd, Mn, Zn, Ba and Sr. The major cations and anions in CKDu-susceptible groundwater varied Si4+ > Ca2+ > Na+ > Mg2+ > K+ and HCO3- > Cl- > SO42- > NO3- > F- > PO43- > Br-. The higher average values of Si4+, F- and total hardness (TH) were reported in groundwater consumed by communities at risk of CKDu, with average values (in mg/L) of Si4+-46, F--0.62, and TH-178. Considering the Water Quality Index (WQI) values, 73% of groundwater sources are classified as poor water quality, and the groundwater quality mainly depends on the fluoride distribution in the region. According to the Hazard Quotient (HQ), the risk of adverse health effects from exposure to F- and SiO2 increased in magnitude in the order of male < female < children. Health hazards due to As, Cd and Pb exposure fell between the 'no-risk' and 'low-risk' categories. As outlined in this study, continuous monitoring of vulnerable communities for environmental exposures to key groundwater constituents is important in the dry zone of Sri Lanka.

Water quality evaluation by WQI and ICOs for the rivers of Joya de los Sachas and Francisco de Orellana

A monitoring program enabled the evaluation of water quality and the simulation of the pollution dynamics of the rivers in the Joya de los Sachas and Francisco de Orellana cantons in Ecuador. For this assessment one used the WQI (water quality index) and the pollution indices ICOMO (organics contamination), ICOSUS (suspended solids), ICOMI (mineralization), ICOTRO (trophy system), and ICOpH (pH Index). The mathematical model operates with several input parameters, including dissolved oxygen, fecal coliforms, the biochemical oxygen demand (BOD5), turbidity, total solids, total phosphorus, pH, total nitrogen, suspended solids, alkalinity, conductivity, temperature, and the concentrations of nitrates, nitrites, and phosphates. WQI values were obtained from ICO pollution indices. The pollution of the Sacha area is significant, WQI = 0.292, which represents an advanced degree of pollution, since increased BOD values correspond to a high load of organic pollutants. They can originate from household, agricultural, industrial, and soil erosion waste. Likewise, the Sacha River has an ICOSUS = 0.16, which renders water treatment difficult, without impacting human health. Calculated WQI values reveal that the water quality of the Sacha, Basura and Coca rivers is low, being highly contaminated. In contrast, the Huamayacu, Jivino Rojo, Jivino Negro, and Jivino Blanco rivers are commonly polluted.

An Analysis of Springwater Parameter Status for Different Locations in the Rural Hilly Garhwal Region of Uttarakhand

Uttarakhand boasts significant spring, groundwater, and surface water resources, particularly in the Garhwal and Kumaon regions, where year-round waterfalls and springs are abundant. However, efficient utilization of these resources remains limited. Reports from the Uttarakhand Pollution Control Board and Water Commission highlight that many remote villages face issues with high mineral content, particularly calcium hardness, in their water. Nine samples revealed total dissolved solids (TDS) above 500 mg/l and hardness exceeding 300 mg/l, with some containing coliform bacteria. Water quality index (WQI) values showed four samples in the ‘Good’ category, while two indicated poor quality.

Analysis of groundwater and surface water quality using modelled water index and multivariate statistics in Kampala and Mbarara Districts, Uganda

The demand for domestic, public and industrial use of water increases with population growth. However, activities from humans and natural environment have resulted into decline in water quality. The aim of this study was to evaluate the quality of groundwater and surface water collected from Kampala and Mbarara districts of Uganda using water quality index and multivariate statistics. A total of 10 physicochemical parameters (pH, water temperature, chloride, sulphate, nitrate, electrical conductivity, total dissolved solids, total suspended solids, total solids, and phosphate) were measured monthly to evaluate the quality of water in the study districts. Results showed that sulphate, electrical conductivity and total dissolved solids were observed with significantly high values in surface water than the groundwater for both seasons. Among all the parameters measured, electrical conductivity was observed with the highest value (2129.67 ± 1.41 µS/cm) while nitrate concentration (0.57 ± 0.02 mg/L) was observed with the lowest during the wet season in surface water. In addition, the mean values of nitrate, electrical conductivity, total dissolved solids and sulphate detected in the groundwater and surface water were within the recommended limits, while phosphate and chloride were observed with mean concentrations above the regulatory limits in 50% of the samples. The correlation analysis revealed strong and positive association between electrical conductivity and total dissolved solids in groundwater and surface water for both seasons. Also, the chemical make-up of groundwater and surface water within the study districts revealed that the determination of water quality rests on two major indices (conductivity and anthropogenic-pollutants) based on the factor analysis. The two indices accounted for 0.619% in groundwater and over 0.70% in surface water, indicating more pollution in surface water. Moreover, the water quality index (WQI) values obtained ranged from 14.81 to 115.73 in dry season and 7.77 to 108.24 during the wet season. According to WQI classification, 42% of the samples collected fell within the “excellent” and “good” categories while others fell within “poor” and “unfit” categories (58%) during the dry season. Based on these findings, appropriate treatment methods, proper sanitation and waste management should be implemented in locations with critical water conditions. Also, frequent monitoring of groundwater and surface water quality by environmental protection agency is highly recommended.

Assessment of water quality in the piped water supply system by using Water Quality index method

Background Drinking water of the right and approved quality is a basic requirement for the development of any civilization. According to SDG 6 it is crucial to provide every citizen with equitable water quality and quantity. Methods The study area is the smart city of Bhubaneswar with 67 wards and three zones: the north zone, south-west zone, and south-east zone with around 12.4 lakh population. To maintain the water quality in the supply pipeline in this city, which is always assumed to be safe, it needs to be examined within certain time intervals to check the contamination. In this context, studies on water quality parameters in the supply pipeline network from different anticipated vulnerable areas have been collected for testing. In this context, water samples were collected from areas near industries, market complexes, educational institutions, and construction sites of each ward of Bhubaneswar. Nearly 10 water quality parameters were tested and analyzed using the weighted arithmetic water quality index method. This method takes input of all the parameters and provides the overall water quality index value, which classifies the water in different grades like excellent, good, poor, and very poor quality. Results According to the WHO (2011) guidelines, the study found that there is a deviation in the parameters like 10.78% in pH, 19.48% in dissolved oxygen, 43.88% in conductivity, and 22.95% in hardness from the standard limit, but the overall water quality index indicates the water is not in the poor and very poor range. Also, water quality index values identify that the water in the south-east zone is excellent compared to the north and south-west zones. The reason for the slight deterioration is due to the underground cable works, road works and also some areas where the old pipeline system is still existing due to personal encroachment of people as per Public health Engineering department.

Chemical Spatiotemporal Characteristics and Environmental Driving Factors of Groundwater in Hetao Irrigation Area

To explore the chemical characteristics and environmental factors of groundwater in the Hetao Irrigation Area of Inner Mongolia, five irrigation fields, including UulanBuh, Jiefangzha, Yongji, Yichang, and Wulat, were selected as the research area. From 72 groundwater observation wells, a total of 216 groundwater samples were collected throughout three typical periods： the end of freeze-thaw （March）, the middle of irrigation （July）, and the end of autumn watering （November）. Comprehensive methods were utilized, such as statistical analysis, Piper three-line diagram, Gibbs diagram, ion ratio, and principal component analysis, to explore the changes in the groundwater chemical environment and the environmental driving factors of groundwater component formation. The groundwater drinking suitability was evaluated using the water quality index （WQI）, and the irrigation suitability was analyzed using the USSL and Wilcox plots. The results indicated that the groundwater in the research areas was generally saline, and the total anion and cation concentrations in each period in ascending order were as follows： late freeze-thaw stage, late autumn irrigation stage, and mid-irrigation stage, with Na+ and Cl- being the major contributing ions. The chemical type of groundwater was dominated by Cl-Na, followed by Cl·SO4-Ca·Mg and a coexistence with SO4-Ca·Mg, HCO3·Cl-Na, HCO3-Na, and HCO3-Ca·Mg. Based on WQI values, the shallow groundwater in Hetao Irrigation District was mainly classified as Class IV and Class V, and the quality was poor in general. According to the USSL diagram and Wilcox diagram, the comprehensive evaluation results showed that the salinity and sodium concentration of shallow groundwater in the irrigation area were generally high. A total of 80.6% of the water samples during the late freeze-thaw period, 76.1% during the mid-irrigation period, and 77.6% during the late autumn irrigation period lacked irrigation suitability. Two major controlling factors of groundwater chemical characteristics were present in the study area, namely, evaporation and rock weathering, and Na+ and Cl- mainly came from the dissolution and cation exchange of salt rocks. Agricultural irrigation and drought were the chief driving factors of groundwater chemical evolution in the Hetao Irrigation Area. The study provides technical support for optimizing agricultural management measures and a theoretical reference for rational utilization of groundwater resources in the Yellow River irrigation area of Inner Mongolia.

Multivariate analysis of water quality in the Dhaleshwari River, Bangladesh: identifying pollution sources and environmental implications

ABSTRACT This study aims to evaluate the current water quality status of the Dhaleshwari River, considering seasonal variations, and identify potential pollution sources using physicochemical parameters, multivariate statistical analysis, and the water quality index (WQI) method. Sampling was conducted at six locations along the Dhaleshwari River from January 2021 to April 2022, encompassing both dry and wet seasons. Eleven physicochemical parameters were tested following standard procedures. The calculated WQI values demonstrated that the overall water quality of the Dhaleshwari River is very poor (264.7 ± 64.5). Seasonal variation in water quality was significant, with the worst quality (305.7 ± 54.3) observed during the dry season; however, water quality during the wet season was also unsatisfactory (223.6 ± 46.3). Geospatial analysis shows the distribution of water quality in the study locations. Principal components analysis was performed for source appointment, which indicated that direct wastewater discharge from surrounding industries, particularly tanneries, as well as municipal wastewater, were the major pollution sources. In conclusion, this study sheds light on the deteriorating water quality of the Dhaleshwari River due to industrialization and human activities. The findings underscore the urgent need for interventions to mitigate pollution sources and improve the overall health of the river ecosystem.

Spatial and temporal variations of dug well water quality in Korba basin, Chhattisgarh, India: Insights into hydrogeological characteristics

Comprehensive assessment of groundwater quality in mining-affected regions is crucial to sustainably manage water resources and protect public health and ecosystems. This study investigated the hydrogeochemical characteristics and water quality of 18 dug wells in the Korba basin, Chhattisgarh, India, an area heavily impacted by coal mining activities. Water samples were collected over three seasons (pre-monsoon, monsoon, and post-monsoon) and analyzed to determine physicochemical parameters, major ions, trace elements, and carbon content. Results revealed very high total dissolved solids concentrations ranging from 315 to 19,738 mg L−1. Nitrate levels surpassed the Bureau of Indian Standard (BIS) limit of 45 mg L−1 in over 50% of samples, reaching a maximum of 200 mg L−1. Fluoride concentrations in all samples exceeded the BIS limit (1.5 mg L−1), ranging from 1.5 to 15.2 mg L−1. The predominant water type was Ca-Mg-HCO₃, primarily influenced by rock-water interactions. Factor analysis indicated that both geogenic and anthropogenic processes influence pollution levels. Pollutant concentrations exhibited seasonal variations, generally peaking during the monsoon period. Temporal analysis from over six years revealed increasing trends for most parameters, indicating deteriorating water quality. Based on Water Quality Index values, all samples were classified as unsuitable for drinking, while assessments of irrigation water quality using various indices indicated that 61.11% of samples were suitable for agricultural use. The findings provide data to inform decision-making and public health protection in this heavily industrialized region and emphasize the urgent need for sustainable water resource management and pollution prevention strategies in the Korba basin to align with UN Sustainable Development Goals 3 (good health and well-being) and 6 (clean water and sanitation).

Evaluating Groundwater Quality for Drinking and Irrigation Purposes and Health Risk Assessment in West Midnapore District of West Bengal, India

Groundwater quality in the West Midnapore district of West Bengal, India is affected by anthropogenic activities as well as by water quality of Subarnarekha and Kangsabati rivers. This study aims to assess quality of groundwater and river water for drinking and irrigation usage, and assess the health risks of the people consuming the water across the rivers. The study also explores the groundwater-river water interaction. The river water and groundwater samples were collected three times during monsoon season from 14 sites across the rivers. The samples were analyzed for 11 water quality parameters, i.e., pH, total dissolved solids (TDS), total hardness (TH), major anions and cations, and iron (Fe). The groundwater was found slightly acidic (mean pH ~ 6.71) and correlated with nitrate concentrations. Most of the water quality parameters were found within their permissible limits of drinking water. However, elevated concentrations of potassium (K), ammonium (NH4), magnesium (Mg), phosphate (PO4), sodium (Na), and Fe were detected at some places, which were likely due to use of fertilizers. Water quality index (WQI), sodium absorption ratio (SAR), and percentage Na values were computed to evaluate the groundwater quality. The mean WQI value of 37.07 showed that the majority of groundwater samples met drinking water standards. Groundwater was also found suitable for irrigation (SAR ~ 0.26 to 1.62 meq L-1 and percentage Na ~ 13.10% to 78.12%). Health risk assessments suggested minimal immediate risks, though high Na levels in certain areas raised concerns. Piper plot showed that increased calcium concentrations in groundwater were mainly due to interactions between river water and groundwater. Overall, groundwater quality did not present any harmful health hazards to the community. The findings of this study can be instrumental for groundwater managers in identifying potential areas for treating groundwater quality.

Assessment of Groundwater Quality and Hydrochemistry using Water Quality Index in District Mirpur Khas, Sindh, Pakistan

Groundwater is a major source of drinking water in the rural areas of Sindh province, including District Mirpur Khas of Pakistan. This study was undertaken to evaluate the suitability of groundwater in Mirpur Khas for drinking purposes. In October and November 2018, the groundwater samples were collected from 50 bore wells and analyzed 17 physico-chemical parameters. The pH ranged from 7.8 to 8.8, indicating the slightly alkaline nature of the water. The mean abundance of major cations is Na+ &gt; Ca2+ &gt; Mg2+ &gt; K+ and for major anions, it is SO42– &gt; Cl– &gt; HCO3– &gt; NO3– &gt; F–. The hydrochemical facies of groundwater samples show that 29 have a mixed composition, Na+-K+-Cl– characterized by 17 and the remaining 4 fall into the Ca2+-Mg2+-HCO3– category. The water quality index (WQI) was calculated based on WHO standards for drinking water using 16 physico-chemical parameters. The computed WQI values range from 20.4 to 503.1. Out of the 50 samples, 9 are classified as ‘excellent,’ 21 as ‘good,’ 13 as ‘poor,’ 4 as ‘very poor,’ and 3 as ‘unsuitable for drinking.’ The average WQI value is 118.7 for 50 samples, which falls under the ‘good’ category. Turbidity and EC exhibited the highest mean effective weight values, indicating their significant influence on the WQI values.

Application of Geographical Information System –Water Quality Index Techniques for Evaluating the Groundwater Quality in Kaniqirzhala Landfill, Kurdistan Region, Iraq

The aim of the current study through uses the Water Quality Index for drinking and irrigation purposes and Heavy Metal Pollution Index to determine quality groundwater in 25 wells spread throughout Kaniqirzhala landfill within the Erbil governorate during 2022. Groundwater samples from various wells have been gathered for chemical and physical analysis in order to determine the water quality. Turbidity, pH, electrical conductivity, total dissolved solids, total alkalinity, total hardness, major anions (SO4-2, Cl-1, Hco3-1, NO3-2, PO4-3) and major cations (Ca+2, Mg+2, Na+1, K+1) are all included in the analysis. In addition to heavy metals investigations were conducted on a variety of metals, including manganese (Mn), nickel (Ni), zinc (Zn), arsenic (As), barium (Ba), boron (B), cadmium (Cd), copper (Cu), iron (Fe), and lead (Pb). Results indicated that higher values of nitrate were calculated in sites 10 to 17. But, in all wells higher concentrations of alkalinity and total hardness were recorded .The concentrations of heavy metals in wells water ranged from low to high according to WHO guidelines for drinking purposes. Drinking water quality index ranged from 52.20 (good quality) at site 9 to 137.01 (poor quality) at site 14. The value of the irrigation water quality index, which is low at site 15, which indicates low restriction for irrigation uses, while the value of 50.01 recorded at site 4 indicates high restriction for irrigation purposes. In all groundwater sites under study, a heavy metal pollution index of greater than 100 indicates extremely poor water quality unsuitable for human consumption. This study concluded all examined wells were deemed to be of extremely poor to good quality for to use in for drinking water based on the water quality index, while extremely low quality based on the heavy metals pollution index .

Monitoring and Evaluation of Water Quality in Underground Aquifers Using (GIS) and (IWQI): Western Karbala’a as a Case Study

Abstract: This study aims to provide an assessment of the current state of groundwater quality and to provide a combination of water quality criteria that may be utilized to develop the irrigation water quality index (IWQI), a suitable technique for classifying irrigation water. Seven wells’ worth of water were collected in the region under evaluation, and their physical and chemical characteristics, such as cation and anion concentrations, were examined. An interpolation method called “Inverse Distance Weighted, IDW” was employed in a geographic information system (GIS) to analyze the data obtained. The water may be labelled as “severe restriction, SR” because the projected values of the irrigation water quality index (IWQI) were more than zero but less than 40. Throughout the six-year period (2017, 2018, 2019, 2020, 2021, and 2022), water samples from seven wells in the study area have been analyzed for their major and minor components. The finding shows that the irrigation water quality indexes (IWQIs) for 2017 and 2018 had measured values above zero but below 55, whereas IWQIs for the other years had calculated values below 40. Therefore, the water can be identified as “High Restriction, HR,” in the early years and as “severe restriction, SR,” in the latter years. As a consequence, this water cannot be utilized for irrigation, and it is abundantly evident that there will be a shortfall in the value of IWQI for a number of years in a row.

Hydro-Geochemistry and Water Quality Index Assessment in the Dakhla Oasis, Egypt

Water quality is crucial to the environmental system and thus its chemistry is important, and can be directly related to the water’s source, the climate, and the geology of the region. This study focuses on analyzing the hydrochemistry of specific locations within the Dakhla Oasis in Egypt. A total of thirty-nine groundwater samples representing the Nubian Sandstone Aquifer (NSSA) and seven surface water samples from wastewater lakes and canals were collected for analysis. Key parameters such as pH, electrical conductivity (EC), and total dissolved solids (TDS) were measured on-site, while major ions and trace elements (Fe+2 and Mn+2) were analyzed in the laboratory. The water quality index (WQI) method was employed to assess the overall water quality. Hydro-chemical facies were investigated using Piper’s, Scholler’s, and Stiff diagrams, revealing sodium as the dominant cation and chloride, followed by bicarbonate as the dominant anion. The hydro-chemical composition indicates that Na–Cl constitutes the primary water type in this study. This points to the dissolution of evaporates and salt enrichment due to intense evaporation resulting from the region’s hyper-aridity. In groundwater samples, the order of hydro-chemical facies is HCO3− &gt; Cl− &gt; SO4−2 &gt; Na+ &gt; Ca+2 &gt; K+ &gt; Mg+2, while in wastewater samples, it is Cl− &gt; Na+ &gt; SO4−2 &gt; HCO3− &gt; Ca+2 &gt; Mg+2 &gt; K+. When considering iron and manganese parameters, the water quality index (WQI) values suggest that most groundwater samples exhibit excellent to good quality but become poor or very poor when these elements are included. This study could prove valuable for water resource management in the Dakhla Oasis.

Groundwater quality assessment using revised classical diagrams and compositional data analysis (CoDa): Case study of Wadi Ranyah, Saudi Arabia

This research aims to assess the status and chemical properties of groundwater in the shallow aquifer of the Wadi Ranyah region, Saudi Arabia, using robust statistical methods (CoDA) that take into account the unique characteristics of chemical analysis data from forty-five (45) groundwater samples collected in the Wadi Ranyah valley. A centered logarithmic transformation (clr) approach and isometric logarithmic transformation (ilr) plots for compositional data were utilized to determine the different water types and to understand the hydrogeochemical processes influencing groundwater chemistry in the region. The results of principal component analysis and K-means clustering reveal the existence of three groundwater groupings: (i) The first group occupies the recharge region with a relationship between trace metal elements (F, Pb, Mn, Zn), pH, and TDS, indicating the effect of alteration of igneous and metamorphic rock minerals. (ii) The second group characterizes the downstream part of the Al-Hujrah area with a relationship between calcium and nitrates, indicating the influence of agricultural activities. (iii) The third group, located in the Ranyah area, shows a relationship between major ions (Na+, SO42−, Mg2+, HCO3–, Cl−, K+), which explains water mineralization influenced by silicate weathering and evaporation phenomena. According to the modified Piper diagram (ilr Piper), two hydrochemical facies are identified. The upstream region is categorized as Ca-HCO3– while the downstream region is classified as Na-K-HCO3–. Calculated water quality index (WQI) values indicate that all Wadi Ranyah groundwater samples are of very poor quality (WQI > 300). This is due to higher concentrations of polluting elements (Pb, Mn and F), in particular the high lead concentrations which vary between 0.24 and 0.4 mg/L, and are well above the WHO limit (0.01 mg/L) for consumption of drinking water. The application of CoDA for the first time in the study region has provided a more detailed and reliable assessment of the mechanisms governing groundwater quality, permitting suggestions for the management of groundwater resources and defining future research needs.

Assessment of water quality in the Great Zab River (Erbil city, Iraq) exposed to wastewater from different industries using the WQI and GIS-based Python script approaches

ABSTRACT This study was conducted to assess the water quality of the Great Zab River (GZR) under potential pollutant pressure from some industries. The Water Quality Index (WQI) was used to evaluate the results of the water quality monitoring study. WQI and Geographical Information System (GIS)-based Python scripts were used to evaluate the results. Results indicate varying water qualities, ranging from moderate to poor, with fluctuations attributed to pollution from industrial plants mixing with river water. The WQI rating of the GZR before industrial discharges was 57.48, and in the lower part, after discharges, the WQI rating was 56.00, indicating marginal water quality. In contrast, the areas near the Cola Factory, where the river confluence occurs, have WQI values of 43.32 and 44.97, representing unacceptable, poor water quality. The study highlights that the refinery, Cola factory, and power plant locations significantly impact the river's water quality. These findings underscore the urgent need to adopt ecological practices, establish environmental regulations, and implement sustainable technologies to preserve the river's natural state. Concise measures aimed at eliminating pollutant sources and enhancing environmental awareness within communities are essential for the conservation of the GZR and the the protection of its surrounding ecosystems. surrounding ecosystems.

Hydrogeochemical evaluation of groundwater evolution and quality in some Voltaian aquifers of Kintampo South District, Bono East Region, Ghana: Implications from chemometric analysis, geochemical modeling and geospatial mapping techniques

Kintampo South District in the Bono East Region of Ghana is dominated by metavolcanic and metasedimentary rocks of the Birimian and the Voltaian Supergroups, which are reported to show aquifer complexities and quality issues. Therefore, assessment of groundwater evolution and quality is important in this area because of the growing need for groundwater for both agricultural and residential use. The people heavily rely on agriculture as their main source of livelihood, and the agricultural practices could potentially impact the groundwater quality. Consequently, this research aimed to evaluate groundwater appropriateness in the Voltaian aquifers of the Kintampo South District for irrigation and consumption. Irrigation water quality indices, geochemical modeling, hydrochemical graphing, and chemometric analysis were all used in the assessment. The investigation reported potassium ion (K+) as the principal cation in the groundwater, showing concentrations within the range of 0.200 to 61.0 mg/L and a mean of 6.32 mg/L. Bicarbonate (HCO3−) is also the major anion in the samples with values that vary from 2.00 to 238 mg/L and a mean of 27.8 mg/L. Geospatial mapping indicates that these predominant ions show higher concentrations in the central part of the study area. Groundwater evolved from K-SO4-HCO3 to Na-HCO3-Cl water types and other mixed forms, which are influenced by atmospheric precipitation and rock weathering. Geochemical modeling reveals that undersaturation of the groundwater occurs in relation to all the silicate and carbonate minerals in the aquifer. However, most samples show positive correlation with these minerals, suggesting precipitation under pre-existing conditions. Chemometric analysis indicated that the chemical composition of groundwater is controlled by human-induced and geogenic activities. With respect to all hydrochemical parameters, the groundwater is largely deemed safe for residential use based on the computed Water Quality Index values. The groundwater in the district is also appropriate for irrigation, according to irrigation indices of water quality such as the Wilcox diagram, sodium adsorption ratio (SAR), Electrical conductivity (EC), magnesium ratio (MR), and sodium percent (Na%).

Mechanisms of evolution and pollution source identification in groundwater quality of the Fen River Basin driven by precipitation

Groundwater pollution has attracted widespread attention as a threat to human health and aquatic ecosystems. However, the mechanisms of pollutant enrichment and migration are unclear, and the spatiotemporal distributions of human health risks are poorly understood, indicating insufficient groundwater management and monitoring. This study assessed groundwater quality, human health risks, and pollutant sources in the Fen River Basin(FRB). Groundwater quality in the FRB is good, with approximately 87 % of groundwater samples rated as “excellent” or “good” in both the dry and rainy seasons. Significant precipitation elevates groundwater levels, making it more susceptible to human activities during the rainy season, slightly deteriorating water quality. Some sampling points in the southern of Taiyuan Basin are severely contaminated by mine drainage, with water quality index values up to 533.80, over twice the limit. Human health risks are mainly from As, F, NO3−, and Cr. Drinking water is the primary pathway of risk. From 2019 to 2020, the average non-carcinogenic risk of As, F, and NO3− increased by approximately 28 %, 170 % and 8.5 %, respectively. The average carcinogenic risk of As and Cr increased by 28 % and 786 %, the overall trend of human health risks is increasing. Source tracing indicates As and F mainly originate from geological factors, while NO3− and Cr are significantly influenced by human activities. Various natural factors, such as hydrogeochemical conditions and aquifer environments, and processes like evaporation, cation exchange, and nitrification/denitrification, affect pollutant concentrations. A multi-tracer approach, integrating hydrochemical and isotopic tracers, was employed to identify the groundwater pollution in the FRB, and the response of groundwater environment to pollutant enrichment. This study provides a scientific basis for the effective control of groundwater pollution at the watershed scale, which is very important in the Loess Plateau.

From land to sea: Environmental DNA is correlated with long-term water quality indicators in an urbanized estuary

Estuaries provide critical ecosystem services, and yet are increasingly under threat from urbanization. Non-invasive approaches to monitor biodiversity resident to or migrating through estuaries is critical to evaluate the holistic health of these ecosystems, often based entirely on water quality. In this study we compared tree of life metabarcoding (ToL-metabarcoding) biodiversity detections with measurements of physico-chemical variables (chlorophyll a, turbidity, total nitrogen, total phosphorous, dissolved oxygen) at eight sites of varying degrees of water quality in the Gold Coast Broadwater Estuary (Queensland, Australia). These sites were ranked according to an adapted Water Quality Index (WQI) score. Here, we detected 787 unique taxa, adding 137 new biodiversity records to the region, mostly micro-organisms such as bacteria, ciliates, diatoms, dinoflagellates, and cryptomonads. Sites with the lowest WQI were characterised by higher turbidity, lower dissolved oxygen, as well as higher total nitrogen and phosphorous, which correlated with an increased diversity of bacteria, ciliates, and green algae. Similarly, the composition of taxa was significantly different between sites with variable WQI values for most taxa but was less apparent for larger vertebrate groups. These findings suggest that rapid ToL-metabarcoding biodiversity detections, particularly for lower order taxonomic groups, can serve as valuable indicators of flora and fauna across the tree of life associated with dynamically shifting estuarine health along urbanized coastlines.

Assessing RO and NF Desalination Technologies for Irrigation-Grade Water

In this work, the performance of a Reverse Osmosis (RO) process using different types of reverse osmosis (RO) and nanofiltration (NF) membranes is evaluated for brackish water desalination for producing irrigation-grade water. The proposed desalination system is a single-stage system, where three types of RO and two NF membranes were examined. The different desalination systems were simulated using ROSA72 software. In order to validate the theoretical model, the results obtained from the simulation were compared to those obtained from the experiment conducted in this work. The El-Moghra aquifer of Egypt is considered the test bed due to a considerable amount of data being available for this aquifer. The El-Moghra aquifer has 79 wells, and the available water data, when checked against several quality parameters, show that none of the investigated wells are suitable for direct irrigation without treatment due to problems of salinity, the sodium adsorption ratio, and low water quality according to the irrigation water quality index values. The obtained results show that nanofiltration membranes exhibited superior energy efficiency compared to reverse osmosis membranes. However, what sets the nanofiltration membranes apart is their ability to elevate water quality in 89.9% of the total investigated wells to an acceptable level for agricultural purposes. This underscores the nanofiltration membranes as a highly effective alternative to reverse osmosis membranes, demonstrating the capability to produce water suitable for irrigation while concurrently reducing operational costs due to the lower energy consumption in nanofiltration-based systems.