Preliminary study on physico-chemical characteristics and determination of selected pollutants in Mirissa and Puranawella harbours, southern coast, Sri Lanka

Abstract

Pollution caused by anthropogenic • influence is one of the major problems in coastal areas. Mirissa and Puranawella harbours are situated along the southern coast of Sri Lanka where intensive fishing activities take place. Therefore, both of these harbors are thought to be affected by acute storage of pollutants including crude oil, raw fish particles and other waste products from fishing vessels and other harbour activites. This study was carried out to study physico-chemical characteristics (pH, temperature, salinity, alkalinity, dissolved solids, dissolved oxygen, biological oxygen demand, total phosphorous, nitrate, and nitrite) and to identify some pollutants (floatable grease and oil, Cd, Pb, Cu and presumptive coliforms) in the two harbours. Monthly samples of water and sediments from three selected sites in each harbour were taken during the period of March 2007 to July 2007. All samples were taken from the water surface, middle part of the water column and from the bottom of each site. Significant variations between sampling sites in Mirissa harbour were observed for pH, temperature, salinity, ortho-phosphorous, nitrate and nitrite (P