Pastoralism in the highest peaks: Role of the traditional grazing systems in maintaining biodiversity and ecosystem function in the alpine Himalaya

According to the states 2012 livestock census the communities rear 951 heads of cattle, 2588 yaks, 141 horses, 230 sheep (indigenous variety) and 90 goats [49]. Historically both communi- ties conducted trade and practiced pastoralism [50,51]. They used to take their yak and sheep upto Khambazong in TAR, China in summer and traded oil, sugar and fir planks for wool, barley flour (tsampa), salt, carpets, mutton and sheep fat. After the 1962 Sino-Indian war the international border was closed off. Now, both communities practice seasonal transhumance. The Lachenpas move to the high elevation pastures in the summer and retreat to lower eleva- tions in the winter, while the Dokpas do the opposite, moving onto the Tibetan Plateau where they find wind-blown, snow-free pastures in winter. Both communities rely on common prop- erty resources (pastures, forests, and natural waters) and some pastures on state forest depart- ment and military property. Vegetation sampling Herb and graminoid species were sampled in grazing pastures and ungrazed areas. Grazed areas were defined as pastures most often in use and that have been grazed for atleast two decades. The ungrazed areas were defined as areas with a history of no grazing for ateast 10 years with permanent fences around them. These areas are used by the locals to make hay. The herbs s are left to grow in these areas throughout the year and removed at the end of the grow- ing season. Local pastoralists and village representatives were consulted to select grazed and

Fig 1. Map of study site with experimental plots. Elevation classes displayed were prepared using Digital Elevation Model (DEM) derived from ASTER data [52]. https://doi.org/10.1371/journal.pone.0245221.g001 PLOS ONE Role of the traditional grazing systems in maintaining biodiversity and ecosystem function in alpine Himalaya PLOS ONE | https://doi.org/10.1371/journal.pone.0245221 January 7, 2021 4 / 19