Vegetation structure and community patterns of Tehri Dam Submergence Zone, Uttarakhand, India

Abstract

The present paper deals with the vegetation structure and community patterns within and between various plant communities in the Tehri Dam Submergence Zone in Garhwal, in the western Himalaya, Uttarakhand, India. The submergence zone is comprised of two valleys, the Bhagirathi submergence zone and the Bhilangna submergence zone. Four major plant communities were identified in both the submergence zones with varied associations through TWINSPAN. Most of the communities are similar in both the submergence zones, while their associations altered due to the micro-climatic variations. The species richness and diversity was high in most of the sites in the Bhagirathi submergence zone compared to the Bhilangna submergence zone, where species richness and diversity were more or less similar in most of the sites. The evenness values in most of the sites indicate that the species were distributed evenly in the Bhagirathi submergence zone, while heterogeneously in most of the sites in the Bhilangna submergence zone. However, the rate of species change, for example, the sdiversity was higher in the Bhilangna submergence zone compared to the Bhagirathi submergence zone. The biomass of Lantana (74.5%) was high for the entire submergence zone compared to Carissa (25.4%), with respect to the total available biomass for both species. However, the extraction was more for Carissa (2.2%) as compared to Lantana (1.2%), with respect to the total biomass of each species.