Seasonal Variations of Heavy Metals in the Soil Around a Coal-Fired Thermal Power Plant, South-West Coast of India

This study focuses on seasonal variations of heavy metals in the soil around a coal fired thermal power plant in Udupi district, which is a densely populated town in the tropical southwest coast of India. This study, pertaining to 48 soil samples, collected during the pre-monsoon, early-monsoon, monsoon and post-monsoon seasons for one year, reveals that the chemistry of collected soil samples is influenced by non-pedogenic (anthropogenic) sources such as fly-ash deposition from the thermal power plant and vehicular emissions. This was concluded based on grouping of similar behaved elements through correlation–regression analysis. The distance-wise distribution of heavy metals and backward wind-trajectory analysis suggests that pre-monsoon and post-monsoonal samples are more influenced by anthropogenic activities compared to rest of the seasons. This is supported by high concentration of Zn in pre-monsoon (25.21 mg/kg) and post-monsoon (21.32 mg/kg) seasons compared to early-monsoon (17.05 mg/kg) and monsoon (8.60 mg/kg) seasons.