Temporal and spatial variations of ecological security on the northeastern Tibetan Plateau integrating ecosystem health-risk-services framework

Ecological security is a critical guarantor of human security and indeed human survival and is closely associated with sustainable development. Yet exploration of ecological security assessment in alpine pastoral regions is lacking, and many studies have failed to perform validation analyses on ecological security assessment results, weakening the reliability of their assessment results. In this study, an ecosystem health-risk-services framework is developed to assess the ecological security of the Gannan alpine pastoral region (GAPR) on the northeastern Tibetan Plateau from 2000 to 2020. Then, the remote sensing ecological index (RSEI) and high-resolution images are then introduced to verify and compare the results' reliability. Our study results indicate: (1) The assessment framework can better reflect the actual ecological security state in GAPR, and the correlation coefficient (R-2) of the comprehensive ecological security index (CESI) and RSEI is between 0.426 and 0.555 (p < 0.001). (2) The CESI value of GAPR shows a fluctuating and increasing trend from 2000 to 2020, with a spatial distribution pattern of high values in the south and low values in the north. The ecological security levels in GAPR are dominated by medium, medium-high and high security levels. (3) The centers of gravity of low and medium-low security levels show a northward movement trend, while that of medium-high and high security levels show a southward movement. Our framework provides a new perspective for ecological security assessment methods, which can be extended to other regions, and the results contribute useful references to decision-makers for socioeconomic development and eco-environmental protection in GAPR.