Commercially important medicinal and aromatic plants of Nepal and their distribution pattern and conservation measure along the elevation gradient of the Himalayas

Abstract

This study aims to assess and evaluate the number of commercially important medicinal and aromatic plants (MAPs) found in the trade and explore their distribution pattern and conservation measures along the Himalayan elevation gradient of Nepal. The species data for this study are based on primary as well as secondary sources, where as elevation range data are based only on secondary sources. The number of MAPs species and number of conservation sites present in each 100 m elevation band is estimated by interpolation. The assessed numbers of commercial MAPs are assigned in to different life forms group to find the life form spectrum of commercial species. The number of MAPs species and conservation sites present in each 100 m elevation band are evaluated as a response variable where as elevation gradient is the predictor. The relationship between them is elucidated by scatter plot as well as generalised liner models. In this study, we have assessed 143 species as commercial MAPs. The variation of MAPs species is found related to elevation. The MAPs species richness increases with increasing the elevation up to 1000 m then decrease with further increasing the elevation thus unimodal type of pattern is observed. The maximum numbers of MAPs are found at 1000 m but maximum numbers of conservation sites are found above this elevation range. We did not find the significant pattern between conservation sites and MAPs species richness along the elevation gradient of the Himalayas. The conservation sites of Nepal are less concentrated where MAPs species diversity is rich. Key words: Medicinal and aromatic plants, elevation gradient, species richness, generalised linear model Banko Janakari Vol.16(1) 2006 pp3-13