CHANGES IN SOIL CHARACTERISTICS AROUND COAL-FIRED POWER-PLANTS

The impact of coal-fired power plant emissions on certain physical and chemical properties of the soil was studied. A significant increase i n bulk density and a decrease in porosity were observed at the sites r eceiving higher pollution than the control site. Soil pH was mostly al kaline at the polluted sites, The organic carbon content of the soil i ncreased with increasing pollution load. Thermal power plant emissions have led to significant increases in the soil sulphate sulphur and ex changeable calcium contents, while reducing significantly total nitrog en. Reduction in total-N was positively correlated with the N-minerali zation rate. The changes in total and organic sulphur, exchangeable po tassium, and available phosphorus contents of soil were not significan t. Significant positive correlations were found between dust fall rate and exchangeable Ca2+ and K+ contents of the soil and between ambient SO2 concentrations and soil SO42--S contents. The values of trace ele ments such as Mn, Fe, Cd Cu, Pb, and Ni were higher at sites closer to thermal power plants.