Population Structure and Microhabitat Preferences of the Himalayan Yew (Taxus wallichiana Zucc.) in Panchase Protected Forest in Central Nepal

Abstract

Three species of Taxus occur in Nepal viz, Taxus wallichiana Zucc., Taxus contorta Griff. and Taxus mairei (Lemée and Lév). Taxus wallichiana is an evergreen dioecious plant that thrives under canopy having average life span of 500 years. Non availability of suitable micro-habitat and frugivory declines the number of the species besides its sale for timber. Based on the information collected from the study area, species distribution modeling was implemented in Maxent. Similarly, analysis for the relationships between different variables like temperature, precipitation, soil pH, litter thickness, canopy closure and occurrence of T. wallichiana was performed by using R program. Population of T. wallichiana was found scattered in the study area where it was found between the elevational ranges of 2200m to 2500m. Temperature and precipitation along with other variables had combined role for affecting the micro habitat preferences of T. wallichiana. Our result also showed effects of climate change on distribution of the species. We found that the new possible areas for its distribution will be towards Eastern Nepal. However, there will be no severe effect of climate change in the study area affecting the distribution of T. wallichiana. This study will help in developing new strategies for the conservation and management of T. wallichiana