IMPACT OF INVASIVE ALIEN SPECIES ON BIODIVERSITY AND POPULATION STRUCTURE IN MORNI HILLS OF WESTERN HIMALAYA

Abstract

Species diversity, especially in forests, is one of the most important indices used to evaluate forest productivity, sustainability of forest communities and its ecological functioning and stand structure. Invasive alien species (IAS) are usually considered to be the second greatest threat to biodiversity after habitat destruction. The present study aims to characterize estimate the species richness, dominance of certain species distribution and population structure of major species in the study areas i.e. Kalka, Morni and Pinjore forest range of Panchkula Forest Division, Haryana lies under the Shiwalik mountain range of Western Himalaya. To achieve this, phytosociological study was carried out using quadrat method to assess the impact of IAS on plant diversity. We took twenty quardrats laid down in each site (10×10m for tree layer; 3×3m for shrubby layer and 1×1m for herbaceous flora) in both, invaded sites and control sites (without any IAS). In the study sites, Lantana camara was the major threat to the native flora. In general, diversity index (H) was higher at control site, however, species richness was found to be more in Lantana infested sites for trees and more or less equal for herbs and shrubs in control sites. This indicates the invasion of L. camara after the establishment of tree species in study sites. In all sites, the seedlings have significant more number than saplings and trees. But the conversion of saplings into trees was poor as well as the production of seedlings and their survival rate was very less or drastically reduced. Thus, there is an urgent need of conservation and management of alien invasive species in Himalayas and other parts of Indian forests. Lantana camara infestation can be managed if we utilize it for making handmade papers, handicrafts, baskets, toys, etc. by involving the self help groups and village forest communities.