Anthropogenic fire, vegetation structure and ethnobotanical uses in an alpine shrubland of Nepal’s Himalaya

Abstract

Alpine vegetation of the Himalaya is used as food, medicine or fodder, and is commonly managed with fire by agropastoralists. Prescribed fire can have positive effects on rangeland biodiversity, but studies evaluating its effects in alpine shrublands are scarce. Our objective was to examine the effects of anthropogenic fire on biophysical characteristics, species richness, abundance and composition in an alpine shrubland with socioeconomic value to local peoples in Langtang National Park in central Nepal. We surveyed biophysical variables, vascular plant species richness and composition along three transects at ascending elevations, and conducted interviews with local people and park officials on the use of fire in the region. We found 69 species of vascular plants in 89 plots; species richness was greater in burned plots and with increasing elevation, with 13 species unique to burned plots. We identified 14 indicator species in both burned and unburned plots; eight of them were Himalayan endemics. In burned plots, the indicator species were predominantly grasses and perennial forbs with ethnobotanical uses. This is the first detailed study on alpine shrubland anthropogenic fire in the Nepalese Himalaya. Burning may, at least temporarily, replace woody with more palatable herbaceous species, and weaken the elevational gradient of the shrubland.