Seasonal variation and distribution of sewage pollution indicator and human pathogenic bacteria along Odisha coast

Abstract

Present study consists the microbial and nutrient quality of water along three coasts of Odisha over a period of three years (2008-2010) on seasonal basis (pre-monsoon, summer and post-monsoon). Water samples were examined for total viable count (TVC) and pollution indicator bacteria. Physico-chemical parameters (pH, salinity, dissolved oxygen and biochemical oxygen demand) and nutrient concentration (nitrate, nitrite, ammonium, phosphate, total nitrogen and total phosphorous) were examined to assess the physical condition of water. Highest average value of bacterial population was observed during summer, which may be due to the higher concentration of nutrients and the optimum temperature for bacterial growth. Lowest was recorded during pre-monsoon (Puri and Mahanadi) and post-monsoon (Paradip) season. Significant positive correlation was observed between pollution indicator bacteria and pathogenic bacteria which imply their co-presence, and also with the nutrient concentration which suggest that elevated nutrient load favors the bacterial growth.