Status and Distribution Pattern of Rhododendron Species in Temperate and Sub-alpine Hill Ranges of Mount Esii and Surrounding in Manipur and Nagaland, India

Abstract

Status and distribution of Rhododendrons in a fragile ecosystem (temperate mixed forest and sub-alpine forest) of Mount Esii and surrounding hill ranges were studied. Not surprisingly, these hill ranges supported 8 taxa of Rhododendrons having varied status in the world (2 endemic and endangered, 2 endemic and rare, 1 rare and 3 common taxa). Within the study area, they showed contiguous pattern of distribution and their occurrence were most prominent within the altitudinal range 2,700-2,820m. amsl The local endemic species, Rhododendron macabeanum had highest density (11.9), most frequent in its occurrence (80 %) and also possessed greatest IVI (132.48) thereby acting as the dominant cover among the species of Rhododendron in these hill ranges. Majority of the remaining taxa (R. maddenii ssp. Crassum and R. elliottii; R. triflorum var. bauhiniiflorum and R. johnstoneanum) showed a high degree of competition for space and nutrients and consequently characterized by slow growth rate. These hill ranges proved to be an efficient habitat for Rhododendrons and will serve the purpose of in-situ conservation of Rhododendrons in general and endemic ones in particular. The endemic and endangered or rare species with low IVI (R. triflorum var. bauhiniiflorum, R. johnstoneanum and R. elliottii) should be given immediate attention for ex-situ conservation.