THIS book, which from its first appearance has been the standard text-book of Indian students, has now been brought up to date by the addition of recent advances in Indian geology. The new geological map is an added attraction. Geology of India By D. N. Wadia. Second edition. Pp. xx + 460 + 20 plates. (London: Macmillan and Co., Ltd., 1939.) 24s. net.

Geology of India

Water quality indices (WQIs) are customarily associated with heavy data input demand, making them more rigorous and bulky. Such burdensome attributes are too taxing, time-consuming, and command a significant amount of resources to implement, which discourages their application and directly influences water resource monitoring. It is then imperative to focus on developing compatible, simpler, and less-demanding WQI tools, but with equally matching computational ability. Surrogate models are the best fitting, conforming to the prescribed features and scope. Therefore, this study attempts to provide a surrogate WQI as an alternative water quality monitoring tool that requires fewer inputs, minimal effort, and marginal resources to function. Accordingly, multivariate statistical techniques which include principal component analysis (PCA), hierarchical clustering analysis (HCA) and multiple linear regression (MLR) are applied primarily to determine four proxy variables and establish relevant model coefficients. As a result, chlorophyll-a, electrical conductivity, pondus Hydrogenium and turbidity are the final four proxy variables retained. A vital feature of the proposed surrogate index is that the input parameters qualify for inclusion into remote monitoring systems; henceforth, the model can be applied in remote monitoring programs. Reflecting on the model validation results, the proposed surrogate WQI is considered scientifically stable, with a minimum magnitude of divergence from the ideal water quality values. More importantly, the model displayed a predictive pattern identical to the ideal graph, matching on both index scores and classification values. The established surrogate model is an important milestone with the potential of promoting water resource monitoring and assisting in capturing of spatial and temporal changes in South African river catchments. This paper aims at outlining the methods used in developing the surrogate water quality index and document the results achieved.

Application of Multivariate Statistical Analysis in the Development of a Surrogate Water Quality Index (WQI) for South African Watersheds

The groundwater of Telangana province is well known for its very high fluoride concentration. The main aim of this review is to assess the fluoride contamination, understand the spatial distribution pattern and also evaluate the potential human health risk for adults and children in the Telangana. Fluoride contamination in groundwater is the principal threat to public health in Telangana state in India. It is observed that the mean fluoride concentration in groundwater of ten districts in Telangana showed a decreasing trend: Nalgonda > Warangal > Ranga Reddy > Adilabad > Medak > Khammam > Karimnagar>Hyderabad > Mahabubnagar > Nizamabad. The high fluoride concentration is observed in Nalgonda where the mean fluoride is 5.76 times higher than the recommended limit of 1.5 mg/L for drinking purposes. The fluoride concentration in groundwater derives mainly from the weathering and dissolutions of fluoride bearing minerals. Nalgonda region, the hazard quotient (HQFluoride) for adults and children ranged from 0.79 to 6.54 and 1.07 to 8.84 with an average of 3.01 and 4.07, respectively. In Warangal region, the non-carcinogenic health risk in terms of HQFluoride was found in the range of 0.77 to 2.63 and 1.04 to 3.55 with a mean of 1.46 and 1.97 for adults and children, respectively. Furthermore, children are at highly prone to health risk when compared to adults in the Telangana. Therefore, special care and pure drinking water should be supplied to the rural regions of Telangana.

Spatial distribution and health risk assessment of fluoride contamination in groundwater of Telangana: A state-of-the-art

Accuracy in groundwater quality monitoring plays a vital and decisive role in environment eco-system, human health and agriculture practices The present study aims to identify the relationship bet

Prediction and evaluation of groundwater characteristics using the radial basic model in Semi-arid region, India

Abstract The main objective of the present study is to perform risk assessment of groundwater contaminated by nitrate (NO 3 − ) and evaluate the suitability of groundwater for domestic purposes in the Palani region of South India. Thirty groundwater samples were collected in the study area. Various groundwater quality analysis parameters such as the pH, electrical conductivity, total dissolved solids, total hardness, major cations (Ca 2+ , Mg 2+ , Na + , and K + ), and major anions (Cl − , SO 4 2− , F − , CO 3 2− , and HCO 3 − ) were adopted in this study to evaluate the drinking water suitability according to 2011 World Health Organization (WHO) standards. Piper and Gibbs’s diagrams for the tested groundwater indicated that, due to the influence of rock–water interactions, evaporation, and reverse ion exchange, the chemical composition of groundwater varied. According to water quality index (WQI) mapping results, 46.67% of the sample locations was identified as contaminated zones via GIS spatial analysis. Multivariate statistical analysis methods, such as principal component analysis, cluster analysis, and the Pearson correlation matrix, were applied to better understand the relationship between water quality parameters. The results demonstrated that 40% of the samples could be identified as highly affected zones in the study region due to a high nitrate concentration. The noncarcinogenic health risks among men, women, and children reached 40, 50, and 53%, respectively. The results illustrated that children and women occurred at a higher risk than did men in the study region. The major sources of contamination included discharge from households, uncovered septic tanks, leachate from waste dump sites, and excess utilization of fertilizers in the agricultural sector. Furthermore, using the nitrate health hazard integrated method with the conventional indexing approach ensures that groundwater reliability can be guaranteed, contamination can be explored, and appropriate remedial measures can be implemented. 

https://link.springer.com/content/pdf/10.1007/s10653-022-01237-5.pdf

An integrated approach to explore the suitability of nitrate-contaminated groundwater for drinking purposes in a semiarid region of India

Groundwater quality analysis has become essentially important in the present world scenario. In recent years, advanced technologies have replaced the traditional ones which are being helpful in simplifying the complex works. In this study, multivariate statistical analysis is carried out with the help of SPSS software for 45 groundwater samples of Kanavi Halla Sub-Basin (KHSB). The quality of groundwater is determined for various parameters which were analyzed and their concentration is correlated with other parameters using correlation matrix. The PCA technique is applied on water quality parameters, from which four components are extracted with 80.28% total variance. The extracted components suggest that the sources behind the higher loadings of each factor are by geological, agricultural, rainfall, domestic wastewater and industrial activities. Results of the Kaiser–Meyer–Olkin and Bartlett’s test conducted have value of 0.659 which is greater than the standard value (0.5). Based on water quality index (WQI), it was noticeably depicted that 2/3rd of the KHSB groundwater quality falls under poor to very poor condition, and hardly 26% of groundwater available is portable. Thus, this study contributes the effective use of multivariate statistics and WQI analysis for groundwater quality. It helps in understanding the hydro-geochemistry of the groundwater and also aids in minimizing the larger set of data into smaller set with effective interpretation.

Multivariate statistics and water quality index (WQI) approach for geochemical assessment of groundwater quality—a case study of Kanavi Halla Sub-Basin, Belagavi, India

Fluorine is most electronegative element, never occurs in free state due to its high reactivity. In most of the places of the world drinking water from underground sources is invariably contaminated with fluoride. The concentration of fluoride according to the WHO standard allowed upper limit is 1.5 ppm whereas as per Indian standard, the allowed upper limit is 1.0 mg/litre. Fluoride ion gets contaminated in drinking water due to weathering of the soil and rocks and the groundwater sources of granite belt of Bagalkot district, contain much higher concentration of fluoride (up to 6 or 7 ppm). In this survey it is found that the concentration of fluoride even at 1.34 ppm has caused tooth decay with the permanent brown scales on the teeth.

Studies on Toxicity of Fluoride and Impact of Endemic Fluorosis from Groundwater Resources of Bagalkot District, Karnataka – Geospatial Information System Approach

Water scarcity has become a major problem especially in arid and semi-arid regions due to insufficient rainfall throughout the globe. This has led in serious search for groundwater resources. Kanavi Halla Sub Basin (KHSB) of Ghataprabha River basin drained by Ghataprabha River, Belagavi District of Karnataka state in India has been considered for present study. Electrical resistivity survey was carried out at selected sites using Schlumberger method with four electrode configuration. A total of 22 Vertical Electrical Sounding (VES) were conducted throughout KHSB and representative of different litho units were considered. Data obtained were then interpreted using curve matching technique with IPI2Win software. The interpreted graphs show three to six layers. The various interpreted curve types are of AAK-type, HA-type, A-type, KH-type, HAA-type, KQH-type, AK-type, K-type, HQH-type, H-type and AKQH-type. From the results it shows that the maximum number of curves are associated with A type which refers to hard rock terrain, whereas curve associated with H type indicates water potential site. The expected subsurface strata are interpreted on the basis of observed bore well drilling data. Borewell log reveals soil formation followed by moderately weathered formation, weathered jointed formation, jointed formation, hard formation from top to bottom. Further deep, the formation is devoid of joints and fractures. Therefore, the weathered, jointed formation may be interpreted as water bearing zone. 2-D geo-electric section has been drawn using IPI2WIN over eight selected trends to understand the geometry of the aquifer formed. The investigation was meant to characterize the aquifer in KHSB along with the risk assessment for contaminants through seepage in terms of protective capacity with the help of Dar-Zarrouk (D-Z) parameters such as longitudinal unit conductance (S), longitudinal resitivity (ρ1), transverse unit resistance (T), transverse resistivity (ρt), Electrical anisotropy(λ) and root mean square resistivity (ρm). These were evaluated to know the aquifer conditions in order to demarcate the freshwater bearing zones. South eastern part of KHSB might be contaminated and 30% of the area is weak to poor capacity protective zone for contaminants. The work adequately highlights the practical use of geophysical techniques, combination of geo-electrical modelling, D-Z parameters, borehole log in the groundwater resource assessment process. This technique is highly recommended for the area with similar geological setup.

Delineation of Groundwater Potential Zones using Integrated Approach in Semi-Arid Hard Rock Terrain, Kanavi Halla Sub-Basin, Belagavi District, Karnataka

Venkanagouda B. B. Patil

Papers

Multivariate statistics and water quality index (WQI) approach for geochemical assessment of groundwater quality—a case study of Kanavi Halla Sub-Basin, Belagavi, India

Studies on Toxicity of Fluoride and Impact of Endemic Fluorosis from Groundwater Resources of Bagalkot District, Karnataka – Geospatial Information System Approach

Delineation of Groundwater Potential Zones using Integrated Approach in Semi-Arid Hard Rock Terrain, Kanavi Halla Sub-Basin, Belagavi District, Karnataka