Distribution of macrophytic vegetation in relation to salinity in the Chilka lake, a lagoon along east coast of India

Growth and distribution of the macrophytic vegetation in the Chilka lake in relation to the distribution of salinity were studied during 1996 to 1998 in order to assess its ecological condition. The lake was found to be highly heterogeneous with regard to the distribution of salinity; its value during summer varied from almost negligible (in the northern sector) to as high as 23.65 +/- 8.13 ppt (in the central sector). The inter-seasonal variation of salinity was found to be the highest in the central sector. It was further observed that the western region of the central sector of the lake remained even more saline than the southern sector during summer. Altogether 12 macrophyte species were identified from the lake. The lake, particularly its northern and the central sectors, was found to be extensively colonized by these macrophytes. It was also observed that the distribution of the macrophytes and the massiveness of their colonization were dependent on the salinity condition of the lake. The study suggests that the Lake is threatened to loose its identity, which could be avoided by adopting methods to increase its salinity.