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

This study demonstrates that the pastures in Lachen valley have benefitted from grazing of var- ious livestock suggesting the stocking rates are within or below “carrying capacity”. The tradi- tional rotational grazing system practiced by the communities allow for pasture regrowth and recovery, facilitates resilience and limits degradation. Similar results have been shown by stud- ies from other regions underlining the benefits of rotational grazing [97–100]. Socio ecological systems Driven by external constraints and the benefits of urbanization, the local communities have diversified toward other sectors, particularly the tourism industry and as porters for the Indian army. The most immediate reason for this change was the complete closure of the interna- tional border after the war of 1962 between India and China. This not only ended trade with Tibet, but also led to a loss of access to vast areas of pastures in TAR. In addition to this, the establishment of large army encampments and areas for land mines further reduced areas for grazing to an estimated 40% of the original area [101]. Previously, the transboundary migra- tion also ensured the interaction of a larger pool of pastoral people resulting in intermarriages from a larger region as well as more opportunities to cross breed livestock. Today, most Dokpa children are sent to schools in the city and few return to the rigors of a pastoralist’s life. Some Dokpas prefer working as porters and laborers for the Indian army stationed in the region or

in the tourism industry as guides, porters, and taxi drivers. Lachenpas too are investing more into the growing tourism industry and less into animal husbandry that show diminishing monetary returns. The loss of grazing pastures and access to trade, reduced opportunities for marriage and cross-breeding livestock, and the exposure to modern education and urbaniza- tion have resulted in a reduction in Dokpa population living in the region from 30 households (130 persons) in the 1950’s [101,102] to just sixteen families [102]. Fewer Dokpas and Lachen- pas investing in pastoralism would eventually result in lesser livestock numbers. Conclusion The paper demonstrates that grazing enhances species diversity and productivity indicating that the pastures in the region have benefited from grazing by livestock. The results are signifi- cant in two respects. First, it suggests that a complete ban on grazing, a common practice in protected areas of developing countries [103–105] may not meet its primary objective of conserving biodiversity. Second, the socioeconomic losses because of the grazing ban can be reduced by reintroducing grazing after sufficient research on altered herd sizes and the impacts of specific livestock and grazing intensities. The results suggest that a management strategy that is mutually beneficial for conservation and livelihoods is not just possible but desirable to maintain higher local and regional biodiversity. Moreover, crucial role of the traditional grazing system on biodiversity and ecosystem func-

tion, coupled with disinvestment in pastoralism by the locals poses an imminent threat to the landscape that is an intricate socio-ecological system with a long history of co-adaptation with ruminant animal. Pastoralism is associated with other spillover effects such as illegal timber and fuelwood collection, medicinal plants (often rare and endemic) collection and the negative effects of overgrazing as enumerated by Bhagwat et al. [41]. At the same time this study shows, the absence of grazing may result in loss of biodiversity and reduced ecosystem function. The benefits of the traditional free ranging pastoralism cannot be ignored, and a holistic approach is needed to conserve the rich biodiversity of the region. As studies from the region demon- strate the grazing ban has resulted in reduced incomes [41], increase in monocultures in low- lands, decreased manure production in a state that exclusively practices organic farming [39], spread of gregarious species and perceived increase in human wildlife conflict [41,43]. 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 12 / 19