Spatiotemporal changes of ecosystem health and their driving mechanisms in alpine regions on the northeastern Tibetan Plateau

Abstract

Ecosystem health plays a vital role in the development of regional ecological environment. Gannan Plateau, an important water conservation area in the upper reaches of the Yellow River, is located at the northeastern margin of the Qinghai-Tibet Plateau. Due to the importance of the region, understanding the spatiotemporal patterns of the ecosystem health within this region is particularly critical. Previous studies on regional ecosystem health assessment mainly focused on single ecosystem type such as wetland, forest, and grassland, while there are relatively few studies that comprehensively assessed ecosystem health at high-spatial resolution in Gannan alpine areas. In this study, 11 counties and cities in Gannan Tibetan and Linxia Hui Autonomous Prefecture of the Gansu Province, China were used as the study area. We evaluated the ecosystem health of 154 township units from 2000 to 2020 with methods of Pressure-State-Response model (PSR) and Analytic Hierarchy Process (AHP), using a combination of satellite remote sensing data, social statistics data, meteorological data, and other geospatial data sources. The results showed that overall ecosystems in the southwestern part of the study area exhibited healthier condition than those located in the northeastern part, which is mainly due to the combination of the natural environment and the intensity of human activities in different regions. Over the past 20 years, due to the active implementation of relevant ecological protection and restoration policies by various regional governments and the improvement of the natural environment, the average ecosystem health status of Gannan Plateau has increased by 15.04 %, showing an improving trend in varying degrees or being stable, no declining trend was observed except for a small town. Our results implied that management should take different measures according to the differences of regional ecosystem health level, also pay more attention to areas where the ecosystem health status has not improved.

Keywords

• Ecosystem health
• Pressure-state-response model
• Alpine region
• Yellow river Basin