Rangeland vegetation dynamics in the Altai mountain region of Mongolia, Russia, Kazakhstan and China: Effects of climate, topography, and socio-political context for livestock herding practices

Abstract

Discriminating between climate- and human-induced variation in rangeland quality poses a major challenge for developing policy to sustain herder livelihoods and alleviate herder poverty. We contrasted changes in rangeland vegetation cover across a region - the Altai Mountains of central Asia (China, Kazakhstan, Russia and Mongolia) - that juxtaposes strongly contrasting social, political and economic conditions across a community of herders of shared cultural background (all of Kazakh origin). Our analysis focused on a satellite-derived vegetation index (Normalized Difference Vegetation Index - NDVI) from the Advanced Very High Resolution Radiometer sensor during the period 1982-2013, which included the breakup of the Soviet Union in 1990 and heralded a transition away from pervasive state control on herding practices in many parts of the region. Grassland cover increased with decreasing elevation and increasing precipitation. Grassland also decreased under increased livestock density but was largely unresponsive to the dramatic changes that occurred in the sociopolitical context for grazing practices. Average NDVI values and duration of growing season were greater after the Soviet Union's collapse across the region, trends that precipitation and temperature data indicate were most likely driven by a changing climate. We conclude that rangeland policy development to assure sustainability of herder livelihoods in the Altai Mountain region should focus on climate change adaptation measures rather than modifying herders' grazing practices.