The effect of land use on quality of groundwater: A case study from Jaffna peninsula

Abstract

The study was focused on quality of groundwater in different land use. Sixty eight wells were selected randomly from different land use such as high land crops, mixed crops, banana field and paddy field. Groundwater samples were collected from wells and an analysed periodically from July to December 2007 for nitrate-N, electrical conductivity (EC), total dissolve solid, pH and chloride. The nitrate-N content was determined colorimetrically using the brucine method. The pH and EC were measured by using pH meter and conductivity meter, respectively. Mohr’s titration was used for determine of the concentration of chloride. Results revealed that there was a significant correlation between land use and nitrate-N concentration in groundwater. High nitrate-N concentration of groundwater was observed at highland crops land use followed by mixed crops and there was no significant difference between high land and mixed crops. However, there was no significant difference between highland and mixed crops. Similarly, there was no significant different between paddy and banana. Concentration of nitrate –N in paddy and banana land use was less than the recommended level of 10 mg/l. There was significant different between high land and mixed crops to banana and paddy land use. But, there were no correlation between land use and electrical conductivity, total dissolve solid, pH and chloride in groundwater.