关键词: 生态系统, 服务功能评价, InVEST, PCA, 十大孔兑

Abstract:

The evaluation of large-scale ecosystem service functions is one of the primary research directions in macro-ecology. The proper application of methods and the selection of evaluation factors serve as the foundation for the evaluation of ecosystem service functions. In this paper， the InVEST model and the RWEQ model were employed to calculate the ecosystem service functions of water conservation， soil conservation， windbreak and sand fixation， carbon sequestration capacity， and habitat quality in the Ten Tributaries area respectively. Meanwhile， the PCA module in the ArcGIS was utilized to analyze the coupling mechanism of the impact of independent service types on the comprehensive service functions. The research findings indicate that the spatial patterns of different service functions are mainly influenced by the differences in geomorphic types in the north-south direction and the disparities in the intensity of artificial vegetation construction among the east-west basins. From 1990 to 2020， the water conservation function across the entire area increased by 6.267 mm； the soil conservation function increased by 0.320 t·hm^-2·a^-1； the windbreak and sand fixation function increased by 1.598 t·hm^-2·a^-1； the carbon sequestration capacity increased by 0.684 t·hm^-2·a^-1； and the habitat quality function increased by 0.062. The coupling mechanism of single-item ecosystem service functions on the evaluation of comprehensive service functions varies across different periods. In 1990， the largest coupling effect （PC1， 64.31%） was dominated by carbon sequestration capacity and habitat quality， and the secondary coupling effect （PC2， 29.78%） was dominated by the windbreak and sand fixation function， suggesting that the vegetation condition， habitat diversity， and the intensity of sand control and desertification prevention determined the comprehensive level of ecosystem service functions during that period. In 2020， the largest coupling effect （PC1， 65.52%） was dominated by the windbreak and sand fixation function， and the secondary coupling effect （PC2， 28.72%） was dominated by the habitat quality function， indicating that the intensity of sand control and desertification prevention and habitat diversity determined the comprehensive level of ecosystem service functions during that period. In the past three decades， ecosystem services in the basin have gradually changed from vegetation status and habitat diversity to desertification prevention and control， which reflects the far-reaching impact of human activities on ecosystem services.

Key words: ecosystem, services function evaluation, InVEST, PCA, Ten Tributaries