Assessment of spatio-temporal variation of heavy metals in Tunga reservoir at Gajanur, Karnataka

Abstract

Surface water samples from Tunga reservoir at Gajanur were analyzed quantitatively for the estimation of five heavy metals such as Iron, Manganese, Lead, Copper and Zinc using atomic absorption spectrophotometer (AA 240 FS, Varian) under specific wave lengths. The values of metals analysed found in the increasing order as follows: Cu (0.9%), Mn (9%), Fe (9%), Pb (12%) and Zn (69%). Metals studied are found throughout the study period confirming that heavy metals are naturally occurring in water. The probable sources of heavy metals in Tunga Reservoir are lithogenic, anthropogenic and agricultural runoff. Hence, very low concentrations of heavy metals were recorded which lies within the acceptable limits of BIS and WHO. The data obtained has been statistically analysed for mean, standard deviation and standard error by using SPSS 16.0 package in Microsoft office excel 2007. Inter relationships among the heavy metals has been worked out by adopting Karl Pearson's correlation coefficient using SPSS 10.0 software. The results revealed that, as such no ecological risk to humans from the waters of the reservoir.