Evaluation Of Water Quality Research Articles

Dynamic analysis of groundwater chemistry from 1997 to 2018 in the eastern part of Yongning County, Ningxia Hui Autonomous Region of northwestern China: Integration of Bayesian water quality assessment and health risk assessment

AbstractGroundwater is an important part of water resources, with many characteristics: widespreading, steady changing, good water quality, and usable. Therefore, it is an ideal drinking water source. However, with the rapidly economic development and the accelerated urbanization process, the problem of groundwater pollution has become increasingly serious. In this study, the eastern part of Yongning County was taken as the study area, 30 groundwater samples from 1997 to 1998, 2007 to 2008, and 2017 to 2018 were selected for water quality assessment and health risk assessment. The results showed that the groundwater chemical type had a tendency to change from HCO3‐Ca·Mg type to SO4·Cl‐Ca·Mg type, and the rock weathering was the important factor controlling the groundwater hydrochemistry in the eastern part of Yongning County. The water quality evaluation of Mn and As was grade II, and the water quality evaluation of Cu, Zn, Cr6+, Cd, and Mo was grade I. Both carcinogenic and non‐carcinogenic risks were higher in children than in adults, the acceptable frequency of adults was higher than that of children, and the area with higher risks was distributed in the central and easternmost regions of Yongning County. As was a more sensitive factor to carcinogenic risk than Cr6+. Therefore, we should pay more attention to the governance of As and the health of children's drinking water. Special attention also should be paid to the water environment protection in the eastern parts of Yongning County. Water quality assessment and health risk assessment in the study area lay a foundation for water pollution control and water environmental protection in the future.Practitioner Points The hydrochemical type changes from HCO3‐Ca·Mg type to SO4·Cl‐Ca·Mg type, which is mainly affected by rock weathering. According to the Bayesian water quality assessment: Mn and As was II, and Cr belongs to I is small. As was the main carcinogenic factor, Mn was the main non‐carcinogenic factor, and the risk was higher in children than adults.

Water quality assessment and its pollution source analysis from spatial and temporal perspectives in small watershed of Sichuan Province, China.

Rapid socio-economic development has led to many water environmental issues in small watersheds such as non-compliance with water quality standards, complex pollution sources, and difficulties in water environment management. To achieve a quantitative evaluation of water quality, identify pollution sources, and implement refined management in small watersheds, this study collected monthly seven water quality indexes of four monitoring points from 2010 to 2023, and ten water quality indexes of 23 sampling points in the Shiting River and Mianyuan River which are tributaries of the Tuojiang River Basin. Then, water quality evaluation and pollution source analysis were conducted from both temporal and spatial perspectives using the Water Quality Index (WQI) method, the Absolute Principal Component Scores/Multiple Linear Regression (APCS-MLR) method, and the Positive Matrix Factorization (PMF) receptor modeling technique. The results indicated that except for total nitrogen (TN), the concentrations of other water quality indexes exhibited a decreasing trend, and all were divided into two obvious stages before and after 2016. Furthermore, the proportion of water quality grade of Good and above increased from 73.96 to 84.94% from 2010-2015 to 2016-2023, and the water quality grade of Good and above from upstream to downstream dropped from 100 to 23.33%. From the temporal scale, four and five pollution sources were identified in the first and second stages, respectively. The distinct TN pollutant is mainly affected by agricultural non-point sources (NPS), whose impact is enhanced from 17.76 to 78.31%. Total phosphorus (TP) was affected by the phosphorus chemical industry, whose contribution gradually weakened from 50.8 to 24.9%. From a spatial perspective, four and five pollution sources were identified in the upstream and downstream, respectively. Therefore, even though there are some limitations due to the data availability of water monitory and hydrology data, the proposed research framework of this study can be applied to the water environmental management of other similar watersheds.

Hydrochemical appraisal and suitability for irrigation and portable purposes in eastern Himalayan syntaxis of Tibet Plateau

The formation mechanism and quality evaluation of surface water and groundwater have provided valuable information on water management of alpine catchment, such as Tibet Plateau. However, scarce knowledge of surface water and groundwater has been achieved from Eastern Himalayan syntaxis in eastern Tibet due to harsh and complicated natural and geological conditions. This study collected 60 water samples from the Layue alpine catchment within Eastern Himalayan syntaxis, including 35 samples of groundwater and 25 of surface water. A combination of multivariate statistical analysis, ion ratio analysis, geochemical modeling, hydrogen and oxygen isotope analysis, and water quality index (WQI) analysis was employed to explore hydrochemical processes and irrigation and portable suitability. Results indicate that the groundwater types identified include bicarbonate-calcium, sulfate·chlorine-sodium, and mixed bicarbonate-calcium·sodium, while surface water are sulfate·chlorine-sodium, mixed bicarbonate-calcium·sodium, and mixed chlorine-calcium·magnesium types. Groundwater recharge primarily originates from meteoric precipitation, with recharge elevations ranging from 2216 to 3698 m, while surface water receives both precipitation and groundwater recharge in a proportion of 50.51%–87.96%. Silicate weathering and carbonate dissolution predominantly control the hydrochemical compositions. Sodium adsorption ratios (0.75–88.55) and electrical conductivity (85.20–1686.12 μs/cm) indicate water resource are mostly suitable for irrigation. The entropy-weighted water quality index (97% in total <100) denotes the suitability for portable use. These achievements would provide substantial support for the sustainable water management in alpine areas, especially for Tibet Plateau.

Ground Water Quality Evaluation for Irrigation Purpose: Case Study Al-Wafaa Area, Western Iraq

Ground Water Quality Evaluation for Irrigation Purpose: Case Study Al-Wafaa Area, Western Iraq

Changes in chemical characteristics and toxicity of fluoxetine and humic acid during chlorination

The coexistence of emerging pollutants and dissolved organic matter in wastewater complicates the transformation and generation of disinfection byproducts (DBPs) during chlorination treatment, which is essential for effective water quality evaluation and chlorination optimization. This study used fluoxetine (FLX) and humic acid (HA) as representative substances to analyze changes in their chemical characteristics and zebrafish embryonic developmental toxicity under different chlorination conditions. The analysis of the fluorescence characteristics and Fourier transform ion cyclotron resonance mass spectrometry indicated that chlorination treatment increased the aromatic compound content of the HA solution. FLX addition further increased the presence of aromatic ring structures and oxidized molecules, resulting in the formation of numerous Cl-DBPs with highly unsaturated and phenolic structures. Moreover, different responses in zebrafish embryo development and behavior were found with FLX, HA, and FLX + HA exposures. Cardiotoxicity was linked to changes in the concentration of cTn-I protein and expression of various genes. Prolonged chlorination conditions showed higher toxicities. Correlation analysis found a weak relation between chemical indicators and toxicity data, indicating that both analysis methods need to be considered when analyzing the impact of the chlorination. Further, a combination of chemical analyses and toxicity tests revealed that the FLX + HA solution with chlorination conditions of 3 mg/L for 30 min had lower chemical and toxic effects in this experiment. This study provides valuable scientific insights for the safe discharge of chlorinated water containing FLX and dissolved organic matter, as well as guidance for optimizing chlorination parameters in wastewater treatment.

Land cover object change monitoring and environmental suitability confirmation in Cat Ba Biosphere Reserve of Vietnam

ABSTRACT The study examined the core, buffer, and transition zones within the Cat Ba Biosphere Reserve in Vietnam to assess changes in five land cover categories (water surface, cropland, vacant land, residential land, and forestland) between 2018 and 2022. Additionally, we aimed to evaluate water quality using three indicators (normalized difference turbidity index, normalized difference chlorophyll index, total suspended solids) and air quality using four indicators (nitrogen dioxide, sulfur dioxide, carbon monoxide, ozone) for the 2022 data. Land cover change analysis and monitoring of water and air quality indicators were conducted using the Google Earth Engine platform, employing Sentinel-2 imagery for land cover and water quality assessment and Sentinel-5P images for air quality assessment. The findings revealed correlations between changes in land cover and water and air quality indicators within the Cat Ba Biosphere Reserve. While occasional instances of values surpassing permissible limits were noted, the average values over the 12-month period in 2022 indicated that water and air quality indicators remained within acceptable thresholds. These results suggest effective preservation efforts in the Cat Ba Biosphere Reserve, indicating no significant signs of degradation.

A novel-approach for identifying sources of fluvial DOM using fluorescence spectroscopy and machine learning model

Rivers are well known as one of the most threatened aquatic environments, whose structure and water quality can be deeply impacted by intensive anthropogenic activities. Despite the fact that anthropogenic influences on river ecosystems could indeed be deduced from the composition and chemistry of fluvial dissolved organic matter (DOM), sources of anthropogenic loading to DOM are still poorly explored. Here, by uniting fluorescence excitation-emission matrices (EEM) and principal component absolute coefficient, four sources of DOM from seventeen rivers in major drainage basins of China could be identified, i.e., originating from municipal sewage, domestic wastewater, livestock wastewater, and natural origins, and thus being defined as MS-DOM, DW-DOM, LW-DOM, NO-DOM, respectively. Based on the random forest model, special nodes in EEM could be traced from four sources, respectively. According to parallel factor analysis, DOM mainly contained protein-like, microbial humic-like, and fulvic-like fluorescence substances, among which protein-like was dominant in MS-DOM and DW-DOM, microbial humic-like in LW-DOM, and fulvic-like in NO-DOM. Based on key peaks and essential nodes in EEM, the identifying source indices were first proposed, which could be introduced to simply distinguish the different anthropogenic-derived sources of fluvial DOM. It was associated with intensity ratios of the key peaks and the essential nodes of EEM spectra from four sources, i.e., municipal sewage (MS-SI: Ex/Em = 280/(335, 410) nm), domestic wastewater (DW-SI: Ex/Em = 280/(340, 410) nm), livestock wastewater (LW-SI: Ex/Em = 235/(345, 380) nm), and natural origins (NO-SI: Ex/Em = 260/(380, 430) nm). By statistical analysis, the high identifying source indices of municipal sewage (>0.5) and natural origins (>0.4) values could be related to MS-DOM and NO-DOM, respectively. The identifying source indices of domestic wastewater with 0.1–0.3 might be linked to DW-DOM and the identifying source indices of livestock wastewater with 0.3–0.4 to LW-DOM. Compared with conventional optical indices, the novel identifying source indices showed remarkable discrimination for the sources of fluvial DOM with different forms of anthropogenic disturbances. Hence the innovative approach could be relatively convenient and accurate to evaluate water quality or pollution risk in river ecosystems.

Coordinated analysis of groundwater spatiotemporal chemical characteristics, water quality, and potential human health risks with sustainable development in semi-arid regions.

The emergence of large-scale time-series data and advancements in computational power have opened new avenues for analyzing the spatiotemporal evolution of groundwater chemistry, water quality, and human health risks. This paper utilizes hydrogeochemical methods to elucidate the controlling factors of water chemical components based on the test results of 124 groundwater samples collected from 31 monitoring wells in Fuxin City, Liaoning Province, China, from 2018 to 2021. By integrating the Random Forest and Enhanced Water Quality Index methods for water quality assessment and employing the Human Health Risk Assessment (HHRA) model to analyze human health risks, our findings indicate that the groundwater is mildly alkaline, with SO4·Cl-Ca·Mg and HCO3-Ca·Mg as the dominant hydrochemical types, primarily derived from the dissolution of carbonate and silicate minerals such as dolomite, limestone, and andesite, and cation exchange reactions. The EI_RF water quality evaluation model reveals that the overall water quality in the study area is poor, with Class I and II water quality zones mainly located in the northeastern and central parts of the study area, showing a gradual transition from Class I and II in the northeast to Classes IV and V in the southwest, significantly influenced by NO3-, TH, TDS, and SO42-. The HHRA model results indicate that the potential non-carcinogenic risk of groundwater nitrates has a severe impact on infants, with the spatial distribution being low in the northeast and high in the southwest. Due to industrial activities, agricultural practices, and population growth, certain areas in developing countries such as China and India exhibit nitrate concentrations significantly higher than those in most international regions, highlighting global environmental and public health challenges. This underscores the importance of enhancing groundwater monitoring and implementing measures to mitigate pollution. These research outcomes hold significant implications for the government in formulating rational protection and management measures to ensure the sustainable utilization of groundwater resources.

Spatial–temporal variations of sediment transport rate and driving factors in Shule River Basin, northwest China

The sediment content and transport rate of rivers are crucial indicators reflecting soil erosion, water quality, and water resource management in a region. Studying changes in river sediment transport rates within a basin is essential for evaluating water quality, restoring water ecosystems, and implementing soil and water conservation measures. This study focused on the Shule River Basin and utilized various methods such as moving average, cumulative anomaly, Mann–Kendall mutation test, Mann–Kendall (M–K) trend test, Sen’s slope estimation, Correlation analysis, wavelet analysis, R/S analysis, ARCGIS10.7 interpolation, non-uniformity coefficient, and concentration to analyze data from hydrologic stations at Changmapu (CMP), Panjiazhuang (PJZ), and Dangchengwan (DCW). The research examined the temporal and spatial characteristics of sediment transport rates and identified key driving factors. Findings revealed significant increases in annual sediment transport rates at CMP and PJZ by 12.227 and 4.318 kg/s (10a)−1, respectively, while DCW experienced a decrease of 0.677 kg/s (10a)−1. The sediment transport rate of the three stations had a sudden change around 1994. The average annual sediment transport rates displayed distinct cycles, with CMP, PJZ, and DCW showing cycles of 51a, 53a, and 29a respectively. Additionally, while CMP and PJZ exhibited a continuous upward trend in sediment transport rates, DCW showed a consistent decline. The annual average sediment transport rates of CMP, PJZ, and DCW were 1305.43 kg/s, 810.06 kg/s, and 247.80 kg/s, respectively. These research findings contribute to enhancing the comprehension of sediment dynamics in the arid region of northwest China and offer a theoretical basis for the restoration and management of ecological environments in similar areas in the future.

Occurrences of nitrate-contaminated groundwater in the piedmont aquifers: hydrogeochemical characteristics and health risks.

Groundwater nitrate (NO3-) contamination is a global concern. The distribution patterns, enrichment mechanisms, and human health risks of NO3- contaminated groundwater were investigated using 144 groundwater samples collected from domestic and irrigation wells in the piedmonts of the North China Plain (Beijing and Shijiazhuang areas). The results showed that the groundwater was neutral to weakly alkaline, and 47% of the groundwater samples had NO3- concentrations exceeding 50mg/L, a threshold proposed by world health organization to threaten infants up to 3months. Groundwater NO3- concentrations were generally higher in the Beijing piedmont than in the Shijiazhuang piedmont and decreased with depth in both piedmonts. High-NO3- (> 50mg/L) groundwater was distributed sporadically spatially and mainly was of Ca-Mg-HCO3 hydrochemical facies. Stable isotopes (D and 18O) compositions and NO3-/Cl- ratios indicated that NO3- accumulation in groundwater was primarily due to use of N-fertilizers under agricultural practices, and was associated with groundwater recharge sources such as septic tank leakage and re-infiltration of reclaimed irrigation water. Water quality evaluation showed that groundwater quality was highly dependent on NO3- concentration, with entropy-weighted water quality index values increasing linearly with increasing NO3- concentrations. The potential health risk of high-NO3- groundwater was the most serious for infants in both the piedmonts. Therefore, reducing NO3- input from sources and drinking water intake is recommended to minimize the human health risk.

Hydrochemical characterization and evaluation of irrigation water quality using indexing approaches, multivariate analysis, and GIS techniques in K'sob Valley, Algeria

Irrigation plays a vital role in addressing increasing need for food production and promoting economic advancement. To meet the demands for food supply and economic progress, it is essential to underscore the significance of assessing water quality in dry regions. The current study was carried out to evaluate and predict the suitability of water quality for agricultural use in the K'sob valley in the M'sila region (Northeast Algeria). A combination of irrigation water quality indices (IWQIs), Geographic Information System (GIS) analysis and multivariate statistical methods were used for this purpose. Several physicochemical parameters, such as temperature (T°), hydrogen ion concentration (pH), electrical conductivity (EC), total dissolved solids (TDS), turbidity (Turb), chemical oxygen demand (COD), Ca2+, Mg2+, Na+, K+, HCO3−, Cl−, SO42−, NO3−, NO2−, NH4+, PO4− and SiO22+ were all measured from 40 samples collected at ten surface water locations during four seasons. The concentrations of the main cation and anion were shown as follows: Na+>Ca2+> K+ > Mg2+, and SO42− > HCO3− > Cl− > NO3− indicating mixed Na-Cl-K or Na-SO4 water facies. Significant seasonal variation for each parameter (T, pH, Turbidity, Salinity, COD, NH4+, Cl−, SO4−, and NO2−) was reported (p < 0.05). Additionally, a significant spatial variation (p < 0.05) was observed among different stations for the parameters: TDS, EC, Ca2+, Na+, HCO3−, SO4−, NO3−, and PO43− (p < 0.05). The irrigation water quality index (IWQI), sodium adsorption ratio (SAR), sodium percentage (Na%), Kelly index (KI), and permeability index (PI) had values varying between 28.1 and 56.8, 5.65 and 12.45, 75 and 87, 2.61 and 6.54 and 83, and 97, respectively, and a significant seasonal effect was recorded. According to the Wilcox diagram, 70% of samples were unsuitable for irrigation, while 30% of samples were questionable. The IWQI map revealed that 50% of the samples fell within the very poor category for irrigation, while 20% and 30% of the samples were inside the poor and unsuitable categories, respectively. The principal component analysis (PCA) and hierarchical cluster analysis (HCA) of K'SobValley water revealed three different categories of water based on elemental composition and seasonal variations. The results obtained in this study can be valuable for surface water management. Furthermore, the developed methodology can serve as a useful tool for identifying critical hydrogeochemical components in arid and semi-arid environments related to surface water.

Environmental influences on soil phosphorus dynamics and eutrophication risks in the Three Gorges reservoir Area, Chongqing section

The spatial distribution of soil phosphorus fractions (SPFs) in the Three Gorges Reservoir area (TGRA) is crucial for evaluating water quality and lake eutrophication in the lower reaches of the Yangtze River. Besides, it is also unclear whether climate change and rising elevation will alter the risk of phosphorus loss in this region. To address this knowledge gap, soil samples were extensively collected in Chongqing section of the TGRA and extracted SPFs using a rapid sequential extraction method. Results indicated that Ustifluvents, Haplustepts, and Kanhaplustults are suitable for cultivation but also prone to the risk of phosphorus leaching due to high labile phosphorus concentration. Increased temperature positively affected labile and medium-stable phosphorus, while increased precipitation accelerated phosphorus leaching. Solar radiation has significant effects on medium-stable and stable phosphorus. Additionally, multivariate and redundancy analysis showed that different SPFs were influenced by various environmental factors, but elevation is the predominant factor affecting most SPFs in the TGRA. Northeastern TGRA and areas with lower elevations on both sides of the Yangtze River were more susceptible to phosphorus leaching. This study is expected to provide decision-makers with references and help manage the regional environment in the context of climate change.

Assessing surface water quality in Hungary’s Danube basin using geochemical modeling, multivariate analysis, irrigation indices, and Monte Carlo simulation

Evaluation of water quality is crucial for managing surface water effectively, ensuring its suitability for human use, and sustaining the environment. In the lower Danube River basin, various methods were employed to assess surface water quality for irrigation, drinking, human health risk purposes and the main mechanism control the surface water chemistry. These methods included water quality indicators (WQIs), complex statistical analyses, geographic information systems (GIS), Monte Carlo simulation, and geochemical modeling. Physicochemical analyses of surface water samples revealed primarily Ca–Mg–HCO3− is the dominant water types. Principal component analysis (PCA), ionic ratios and piper, chloro alkaline index, Chadha, and Gibbs diagrams identified three distinct water characteristics influenced by water-rocks interaction, evaporation, ions exchange, and human activities. The geochemical modeling showed Danube River water’s strong ability to dissolve gypsum, halite, and anhydrite (SI < 0) and precipitate aragonite, dolomite, and calcite with saturation index (SI) value greater than 0 along its flow path. The irrigation water quality index (IWQI = 99.6–107.6), sodium adsorption ratio (SAR = 0.37–0.68), sodium percentage (Na% = 13.7–18.7), soluble sodium percentage (SSP = 12.5–17.5), Potential Salinity (PS = 0.73–1.6), and Residual Sodium Carbonate (RSC = − 1.27–0.58) values were used, mainly indicating acceptable quality with some limitations. Danube River water was unsuitable for drinking based on WQI value (WQI = 81–104). Oral exposure of children to specific components showed a higher hazard index (HI > 1) compared to adults, indicating a 2.1 times higher overall non-carcinogenic risk hazard index. However, Monte Carlo simulation demonstrated negligible iron, manganese, and nitrate health hazards for both age groups. These findings are valuable for water quality management decisions, contributing to long-term resource sustainability.

REAL TIME MONITORING OF AIR POLLUTION USING ARTIFICIAL INTELLIGENCE BASED IOT AND NOVEL SARIMA TECHNIQUE IN SIVAKASI - INDIA

&lt;p style="text-align:justify; margin-bottom:13px"&gt;&lt;span style="font-size:11pt"&gt;&lt;span style="line-height:200%"&gt;&lt;span style="font-family:Calibri,sans-serif"&gt;&lt;span style="font-size:12.0pt"&gt;&lt;span style="line-height:200%"&gt;&lt;span style="font-family:&amp;quot;Times New Roman&amp;quot;,serif"&gt;Air pollution, a harmful or excessive quantity of pollutants from natural sources and human activities, poses risks to human health, the environment, and ecosystems. AI breakthroughs have allowed for the incorporation of technologies into performance indices, resulting in the development of an AI-based air quality system that evaluates water quality in real time using WHO-defined parameters. This article describes the implementation and planning of AI-based IoT for air pollution tracking and forecasting utilizing AI methodologies, as well as a dashboard on the internet for real-time tracking of air pollutants via Google Cloud servers. Air pollutants such as NO&lt;sub&gt;2&lt;/sub&gt;, NO&lt;sub&gt;x&lt;/sub&gt;, NH&lt;sub&gt;3&lt;/sub&gt;, CO, SO&lt;sub&gt;2&lt;/sub&gt;, and O&lt;sub&gt;3&lt;/sub&gt; are gathered from IoT sensor nodes in Sivakasi, Tamil Nadu, India, utilizing artificial intelligence algorithms. Individual pollutants are forecasted using time series modeling approaches such as Artificial Neural Network (ANN), Naive Bayes Model, k-nearest neighbour (k-NN), Support Vector Machine (SVM), and Seasonal Autoregressive Interated Moving Average (SARIMA). The data from the IoT sensor node is utilized to train the model, resulting in optimal parameters. The derived model parameters are validated using new, previously unknown data for time. The performances of several Time Series models are examined using performance metrics such as Mean Absolute Error (MAE), coefficient of determination (R&lt;sup&gt;2&lt;/sup&gt;), and Root Mean Square Error (RMSE). An AI-based algorithm has been flashed in the Raspberry Pi 3. The present air pollution data and anticipated data are monitored throughout a 7days from 10 p.m. to 4 a.m. using a digital dashboard built in an open-source using Google cloud services. Finally comparing to all above AI based algorithms, SARIMA performed well and h+ad a 95% accuracy level. &lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/span&gt;&lt;/p&gt;

“Efficiency of Carlson Modeling of Eutrophication of the Inner Bay - Puno Lake Titicaca”

Objectives: Determine the degree of water contamination, expressed as a percentage of pure water; Quantify and evaluate water quality; recognize the sources of pollution and know the most relevant pollutants of the channels and mechanisms of eutrophication. Theoretical Framework: Pollution, water quality, pollution sources, tributaries-channels and eutrophication mechanisms. Method: The trophic state index of Carlson (1977) or TSI (Trophic State Index) was used. It is a longitudinal study from 2008 to 2016. With 15 sampling points, 12 times a year, evaluating the physical, chemical and microbiological parameters at each sampling point at 20% and 80% of the water column. Results and Discussion: Use modeling to predict the concentration of contaminants for the different treatment alternatives. Likewise, give a description of a model to estimate water quality. In conclusion, we indicate that the Carlson trophic state index has determined that the most relevant pollutants in the eutrophication process of the Interior Bay are nutrients and phosphates, these coming from the discharge of domestic wastewater from the city of Puno. Research implications: The study will serve to evaluate the behavior of water quality and implement mitigation policies. Originality/Value: This study will contribute to monitoring and treating wastewater.

Evaluation of ground water quality using heavy metal pollution indices and estimation of health risk

ABSTRACT This paper presents the monitoring of heavy metals, including cadmium (Cd), chromium (Cr), lead (Pb), copper (Cu), and zinc (Zn), in the groundwater of the Byrnihat Industrial Area and Guwahati City, which is located in close proximity to the Byrnihat Industrial Area. A total of 20 water samples were collected at distances approximately 1–2 km apart from each other. The pH and the TDS of the collected samples were analysed immediately after collecting samples using a digital pH and TDS meters. The collected samples were analysed using a Flame type Atomic Absorption Spectrophotometer. The highest observed values of Cd, Cr, Pb, Cu and Zn in mg/L were recorded to be 0.0526, 0.1438, 0.5175, 0.1060 and 0.0925, respectively. The average values of Cd, Cr, Pb, Cu and Zn were 0.0246 ± 0.0168 mg/L, 0.0282 ± 0.0421 mg/L, 0.4805 ± 0.0206 mg/L, 0.0653 ± 0.0276 mg/L, and 0.0642 ± 0.0098 mg/L, respectively. Cd and Pb concentrations were above the guideline values set by Bureau of Indian Standards (BIS) and the World Health Organisation (WHO) [WHO recommended values, Cd: 0.003 mg/L, Pb: 0.01 mg/L]. Though the average concentration of Cr was below the allowable limit, five samples within the Byrnihat industrial area were found to be above the limit. High values of pollution indices was observed for all the samples. The cumulative hazard index (HI) values for adults and children were found to be 8.56 and 9.37, respectively. The total cancer risk (TCR) was observed to be 7.87E-03 for adults and 8.54E-03 for children. The result obtained from the present investigation show significant contamination of ground water by heavy metals, particularly Pb, Cd, and Cr concentrations. The observed high values of hazard index and cancer risks indicate significant health risks, necessitating the need for immediate regulatory action.

Evaluation water quality of Tigris River at the sites of Fish cages in Missan city

Evaluation water quality of Tigris River at the sites of Fish cages in Missan city

Identify the seasonal differences in water quality and pollution sources between river-connected and gate-controlled lakes in the Yangtze River basin

The river-connected Dongting Lake (DT) and Poyang Lake (PY), and the gate-controlled Taihu Lake (TH) and Chaohu Lake (CH) are the four important lakes in the Yangtze River Basin. The comprehensive Water Quality Index (WQI), the Eutrophication Integrated Index (TLI(Σ)), and the Positive Matrix Factorization (PMF) model were employed to evaluate water quality and the contribution of pollution sources for these lakes. The results show that WQI for all lakes indicated generally good water quality, with DT scoring 73.52–86.18, the highest among them. During the wet season, the eutrophication degree of river-connected lake was medium, and that of gate-controlled lakes was high. The surface runoff and agricultural non-point sources are the main pollution sources for both types of lakes, but their impact is more pronounced in gate-controlled lakes during the wet season. The study provides evidence support for scientific understanding of water quality problems and management strategies in these areas.

Hydro-chemical characteristics of Biring and Tangting Rivers (Nepal) and evaluation of water quality for drinking and irrigation purposes

Although river water is vital for drinking, irrigation and domestic needs, it faces threats from natural processes and human activities. Small and medium-sized rivers, especially in Nepal, remain understudied despite their vital importance in providing water to densely populated areas. This study evaluated the suitability for drinking and irrigation and the hydro-chemical characteristics of the Biring and Tangting rivers in Koshi province, Nepal. The results showed that turbidity, pH, EC, TDS, TH, NH4+, K+, Ca2+, Mg2+, Na+, Cl−, SO42−, HCO3− and NO3− values of all sampling sites in the Biring and Tangting rivers, except for the turbidity value of 10.39 NTU recorded in the PT9 site of the Tangting River, did not exceed maximum limit values set for drinking water. However, according to Water Quality Index results, the water of both rivers was in poor condition for drinking due to domestic wastewater discharges and cremation activities which caused high NH4+ levels. The major cations in both rivers were listed as Ca2⁺ > Na⁺ > K⁺ > Mg2⁺, while the major anions were listed as HCO₃⁻ > Cl⁻ > SO₄2⁻ > NO₃⁻. Gibbs and Piper diagrams showed that geogenic weathering of carbonate rocks prevailing in the region affected the hydrochemistry in both rivers. Evaluation based on seven different irrigation indices and US salinity laboratory diagram revealed that the water of both rivers was suitable for irrigation despite some magnesium-related limitations.

Surface Water Quality Evaluation and Pollution Source Analysis at the Confluence of the Wei River and Yellow River, China

Surface Water Quality Evaluation and Pollution Source Analysis at the Confluence of the Wei River and Yellow River, China