How Environmental Change in Central Asian Highlands Impacts High Elevation Communities

Highlanders are different. People gestated, born, and raised at high elevation (>2500 m) exhibit distinct physiological characteristics, including increased blood viscosity due to higher hemoglobin content. Chronic physiological stress and lower reproductive success coupled with the short growing season, long cold season, and harsh climatic extremes associated with the montane agro-pastoralism, make high elevation communities particularly vulnerable to additional stressors.

Prior to the Soviet era, highlanders in Central Asia practiced vertical transhumance to raising livestock--sheep and goats-- for wool, meat, milk, and hides. Collectivization disrupted this practice with multiple external subsidies. Since 1991 montane agro-pastoralism has been disrupted by withdrawal of external subsides and introduction of a market economy.

Our project evaluates four aspects of environmental change in human settlements and associated summer and winter pasturelands in representative areas of Kyrgyzstan (KG) and Uzbekistan (UZ) since the 1970s and projected changes into the middle of the 21st century to assess impacts on these highland communities and the pastures upon which they depend. Our areas of interest are located in the Central and Southwestern Tien-Shan in the highlands of Osh, Naryn, and Issyk-Kul oblasts in southern KG, and Qashqadayro and Surxondaryo in southern UZ.

The four aspects of environmental change are (1) changes in the thermal regime including growing s eason timing and extremes, (2) changes in the moisture regime including peak precipitation timing and snow cover duration, (3) changes in socio - economic conditions including income, education, agricultural production and practices, and institutions, and (4 ) changes in land cover, land use, and land condition including alterations in terrain from landslides and earthquakes.

Key response variables at the scale of human settlements in high elevation regions are the demographic profile (especially aging and ge nder), population outflow, fertility, and infant mortality, as these indicate the aggregate well - being of the communities. Key response variables for pasture condition are the temporal and spatial patterns of spectral indices based on remote sensing data L andsat and MODIS.

Initial synthesis leads us to pose the following linkages: [I] Increasing temperatures reduce snow cover duration and change the growing season in highland pastures, but more warmth may also reduce forage production [II] Increased remitt ances mean more livestock and more grazing pressure on nearby pastures, but not in remote highland pastures, which leads to the declined status of lower pastures nearby human settlements and improved status of higher and more remote pastures and [III] Dif ferential changes in pasture condition and increased remittances led to changes in community well - being, characterized by population decline, population aging, lower fertility rates, higher infant mortality rates, and higher international out - migration and internal migration.

Our fundamental question is whether change in pasture condition can be detected through remote sensing and linked to community well - being through econometric and structural equation modeling. The ancillary question of how climate chang e drives the change of pasture condition can be addressed through remote sensing of land surface seasonality (snow cover metrics) and land surface phenology (vegetation indices) and careful analysis of precipitation station data complemented by remote sens ing of precipitation and soil moisture. The linkage from remittances to community well-being will be tested through econometric and structural equation modeling. Impacts of climate change, changes in pasture condition, and increased remittances on communit y well - being will be used along with forecasted demographic changes to recommend policy strategies for building resilient communities.