Deptt. of Applied Geography, Ravenshaw University, Cuttack, Odisha

The Trophic State Index (TSI) of Chilika Lake has been measured using the Secchi disk transparency as well as Landsat-8 OLI and LISS-III bands. The water quality parameters such as dissolve oxygen, pH, salinity, total suspended solid, turbidity, alkalinity, surface water temperature, ammonia, phosphate and nitrite of Chilika Lake are collected and measured from different sectors during pre and post monsoon period. The result indicates spatiotemporal variations of hydrological parameters during pre and post monsoon season. Different interpolation methods have been evaluated and the best method has been applied to create two dimensional water quality images of Chilika Lake. Analysis of water quality parameters indicated variation in physiochemical parameters with respect of different sectors. The pH of the entire lake is found to be alkaline and salinity of the lake changes from one sector to other due to influx of fresh water from eastern and northern rivers along with the distributaries of the Mahanadi river system. The analysis of LISS III and Landsat -8 images indicate the lake water is in eutrophic condition since the year 2006 to 2014. However, the average TSI values are comparatively less during the post monsoon period of 2013 and 2014. This may be due to the lake restoration program undertaken by Chilika Development Authorities.

Keywords:Interpolation, LISS-III, Landsat-8 OLI, Secchi disk transparency,Trophic state index.