Himalayan ecosystem services and climate change driven agricultural frontiers: a scoping review

Climate change, rising temperatures, snow melts and more frequent droughts and floods are disproportionately affecting food and water security, habitat health, and agricultural productivity in the Himalayan region. These climatic changes are negatively impacting productivity of staple crops including wheat, maize, and rice at lower altitudes, but may provide opportunities to utilize Climate Change Driven Agricultural Frontiers [CCDAFs] at higher altitudes. Agricultural expansion into CCDAFs paired with behavioural shifts such as replacing traditional crop systems with commercial crops will predominantly affect forests, water resources, and soil health, which are already negatively affected by climate change unless adaptation options are directed to just and sustainable agroecological transitions. By trading regulating, supporting, and cultural services for food and water provisioning services, as are evident in land sparing strategy, the utilization of CCDAFs will have long-term implications for the sustainability of mountain farming systems. Climate change is affecting Himalayan agriculture, food security, and ecosystem services, and scientific literature predominantly focus on one of these topics in isolation, occasionally connecting results to another topic. By classifying literature as predominantly agriculture, food security, or ecosystem service themed, this scoping review identifies sources with multiple dominant themes and explores how the relationships between these topics are represented in literature to provide research based evidence to promote the future expansion of agriculture that is low-carbon, just and sustainable. Gaps in the literature reveal that research is needed on the extent of CCDAFs in the Himalayas and the potential trade-offs on utilizing the frontier areas

Climate change creates opportunities to expand agriculture in the Hindu Kush Himalaya but will cause considerable ecosystem trade-offs

Theoretically, climate change will create warmer temperatures and greater precipitation in mountainous regions, making agriculture possible in areas that were once unsuitable for cropping. But the extent and the nature of these ‘agricultural frontiers’ is as yet unknown. Building upon recent research on Climate Change Driven Agricultural Frontiers [CCDAFs], this paper assesses the potential of agricultural expansion in the Hindukush Himalaya [HKH]. Using FAO crop suitability data, we estimated the extent of CCDAFs under three Representative Concentration Pathways for 13 crops as well as the potential impacts of developing these frontiers on ecosystem services. We show that under climate change projected by the IPSL- CM5A-LR climate model, 34,507 km ^2 of agricultural frontiers may emerge in the HKH by 2100 under RCP 6.0. Additionally, results suggest that there will be new opportunities for crop diversification as individual crops will gain frontier area. However, developing these CCDAFs will impact supportive and regulating ecosystem services including carbon storage and sequestration, soil quality, biodiversity, and hydrological processes—with implications for regional water security. These impacts must be considered alongside the benefits of additional food production when evaluating the net benefits of developing CCDAFS