Changes in Physico-chemical Parameters at different Sites of Manasbal Lake of Kashmir, India

In an aquatic ecosystem, the density and diversity of organisms depend on availability and quality of water. During the present study an attempt was made to analyse some of the important physico-chemical parameters of the water samples at three different sites of the Manasbal Lake to check the pollution load. Various parameters were analysed for a period of six months from July 2010 to December 2010 on monthly intervals by following standard methods. Among the various parameters recorded the overall Air temperature ranged from 7.2°C to 30.2°C; surface water temperature ranged from 6.1°C to 26.5°C; Secchi-disc transparency from 1.5 m to 4.5 m; Conductivity varied from 149 to 292 μS cm-1; Dissolved oxygen from 2.5 to 8.8 mg L-1; Free Co2 from 0.2 to 13.4 mg L-1; pH from 8.1 to 9.2; Total Alkalinity varied from 126 to 243 mg L-1; Chloride values ranged from 5.9 to 33.5 mg L-1; Total Hardness ranged from 119 to 218 mg L-1; Ammonical Nitrogen varied from 27 to 193 μg L-1; Nitrate Nitrogen varied from 31 to 286 μg L-1; Ortho-Phosphate Phosphorous varied from 4.3 to 33.0 μg L-1 and Phosphate Phosphorous ranged from 83.0 to 261 μg L-1. Almost all the above parameters showed that the pollution load is increasing especially at littoral sites due to agricultural run-off and human settlements disposing sewage, besides anthropogenic stresses in the catchment area. The pH of water of this lake was higher due to calcium intrusion from Kondabal area. Hence, the present study urges the need for immediate remedial measures for protection and conservation of this lake in order to save it from further deterioration.