Abstract
Qinghai Province has a very fragile ecological environment and is an important component of the Qinghai-Tibet Plateau. To understand the disturbance caused by human activities to the local ecological system, it is necessary to evaluate the response of ecological service functions to land use change in Qinghai Province and to uncover the sensitivity of ecological service functions to land use change. This study uses a proxy-based method and proposes a sensitivity index to describe the degree of ecological service function response to the land use change in Qinghai Province. The findings were as follows. (1) From 1988 to 2008, the area of cultivated land, construction land and water in Qinghai Province increased, and forest land and grassland continuously decreased. The agricultural economy and the development of urbanization are the main driving factors in land use change in this area. Policies and eco-environmental engineering, such as the grain-for-green project, the Three-North shelterbelt project and the natural forest protection project, have certain effects on controlling the expansion of cultivated land. (2) The value of ecosystem services in Qinghai Province was 157.368 billion yuan, 157.149 billion yuan and 157.726 billion yuan in 1988, 2000 and 2008, respectively, decreasing and then increasing again. (3) The average sensitivity index values of ecological services in Qinghai Province for the periods 1988⁻2000 and 2000⁻2008 was 0.693 and 1.137, respectively. This means that for every 1% increase in land use change, the ecological service value fluctuated by 0.693% and 1.137% in those periods.