Evaluation of Groundwater Quality in Northeastern Region of Karnataka, India using Correlation and Regression Analysis
Basavaraja D *
Department of Environmental Science and Agroforestry, College of Agriculture, Hagari, University of Agricultural Sciences, Raichur, India.
J B Kambale
Department of Agricultural Engineering, College of Agriculture, Kalaburagi, University of Agricultural Sciences, Raichur, India.
Jahnavi A P
Department of Agricultural Statistics, College of Agriculture, Hagari, University of Agricultural Sciences, Raichur, India.
D K Hadimani
Department of Sericulture, Directorate of Extension, University of Agricultural Sciences, Raichur, India.
*Author to whom correspondence should be addressed.
Abstract
An attempt has been made in this work to understand the relationship between groundwater quality parameters. Groundwater samples from sixty-five bore wells of the study area were collected during pre and post-monsoon season. The physico-chemical parameters like pH, electrical conductivity, total dissolved solids, total alkalinity, total hardness, calcium, magnesium, chloride, sulphate, fluoride, nitrate and phosphate were determined and recorded their concentrations as per the standard methods. It was observed that groundwater quality was varied between pre and post-monsoon seasons. The concentrations of the most of the parameters were higher in pre-monsoon season due to high atmospheric temperature and evaporation. Statistical analysis was carried out to understand the linear relation between strongly correlated water quality parameters. The relationship for different water quality parameters of the study area was analyzed for two seasons i.e., pre and post‐monsoon, as the quality of water varies seasonally. The correlation matrix shows that electrical conductivity and total dissolved solids were highly significantly correlated and have a strong correlation with alkalinity, total hardness, calcium, magnesium, chloride, sulphate and sodium and this indicates that these ions significantly contribute to conductivity and dissolved solids. The study showed that total hardness was strongly correlated with calcium and magnesium and these ions were might be major contributors to hardness. Similarly, alkalinity was observed to be positively correlated with calcium, magnesium, chloride, sulphate and sodium during pre and post-monsoon season. The regression analysis reveals that the eight pairs of ground water parameters were having highest cause and effect relationship. The study could help to predict the changes of groundwater quality in future and management of water resources.
Keywords: Groundwater quality, correlation coefficient, regression analysis, pre and post monsoon season