Abstract:
Groundwater is a significant source of water in many parts of India. Proper management of groundwater is very important to meet the increasing demand of water for domestic, agricultural and industrial uses. The information on the spatial variability of groundwater quality is useful for proper planning and management of groundwater resources. The knowledge of spatial variability of ground water quality is also essential for making reliable ground water quality interpretations and for making prediction of ground water quality at any unsampled location. The spatial dependence between observations can be expressed by the semi variance, which is a measure of the average similarity between observations at a given distance apart.
In the present study, semi-variogram analysis of 12 ground water quality parameters (pH, EC, total hardness, alkalinity, chloride, nitrate, sulphate, calcium, magnesium, sodium, potassium, phosphate/fluoride) of Jammu, Kathua and Udhampur Districts was carried out for shallow ground water quality data of 40 open wells pertaining to data of 1995 and 2008, respectively. The average range values determined using above data set was found 29 km (calcium), 32.5 km (chloride), 40 km (EC), 37 km (bicarbonate), 32.5 km (potassium), 28 km (magnesium), 22 km (sodium), 31 km (nitrate), 31 km (pH), 29 km (sulphate), 36 km (total hardness), 22 km (phosphate) and 28 km (fluoride), respectively. The analysis has shown that Range/Length "a" values of semi variogram models (mostly fitted with spherical) of GWQ parameters are useful for designing appropriate GWQ monitoring network in the study area. The statistical analysis of ground water quality data has also shown increasing trend of average nitrate concentration from 7 mg/1(1995) to 19 mg/1(2008) in the shallow open wells which indicate the effect of anthropogenic/agricultural activities in the study area.
