Application of Water Quality Index and Multivariate Statistical Techniques to Assess and Predict of Groundwater Quality with Aid of Geographic Information System
Civil Engineering Department, College of Engineering, University of Basrah, Basrah, Iraq
Geology Department, Earth Sciences, HCC, Seattle, Washington, 98198, USA
Department of Soil Science and Water Resources, University of Basrah, Iraq
Ammar S. Dawood   

Civil Engineering Department, College of Engineering, University of Basrah, Basrah, Iraq
Data publikacji: 01-06-2022
J. Ecol. Eng. 2022; 23(6):189–204
In this study, the groundwater quality and spatial distribution of Basra province in the south of Iraq was assessed and mapped for drinking and irrigation purposes. Groundwater samples (n = 41) were collected from deep wells in the study area to demonstrate, estimate and modelling of Water Quality Index (WQI). The analysis of water samples integrated with GIS-based IDW technique was used to express the spatial variation in the study area with consideration of WQI. The phys-icochemical parameters including pH, sodium (Na+), electrical conductivity (EC), chloride (Cl-), total dissolved solids (TDS), calcium (Ca2+), nitrate (NO3-), sulfate (SO42-), magnesium (Mg2+), and bicarbonate (HCO3-) were identified for groundwater quality assessment. The results of calculated WQI classify groundwater into three sorts. The results of WQI showed that 2.5%, 2.5% and 95% of the groundwater samples were classified as poor/very poor/unsuitable for drinking, respectively. The GIS tools integrated with statistical techniques are utilized for spatial distribution and description of water quality. Cor-relation analysis of groundwater data revealed that some parameters have actually a relationship that is strong with the other parameters and they share origin source that is common. Multivariate statistical techniques, especially cluster analy-sis (CA) and factor analysis (FA), were applied for the evaluation of spatial variations of forty-one selected groundwater samples. Cluster analysis confirmed that some different locations of wells has comparable sourced elements of water pol-lution, whereas factor analysis yielded three factors which are accountable for groundwater quality variations clarifying more than 72 % of the total variance of the data and permitted to group the preferred water quality. MLP models were applied in modelling the water quality index. Comparing different result values of the MLP network suggested that the val-ues of MSE and r for the selected model are 0.1940 and 0.9998, respectively. Finally, it can be revealed that the MLP net-work precisely predicted the output, which is the WQI values.