Ecosystem service trade-offs and spatial non-stationary responses to influencing factors in the Loess hilly-gully region: Lanzhou City, China

Abstract

The identification of trade-offs and synergies relationships among ecosystem services is one of the important contents of evaluating the regional ecological environment, and is of great significance to regional ecological governance and sustainable development. In this study, Lanzhou was selected as the research area. Four key ecosystem services, such as habitat quality, soil retention, food production, and ecological leisure were evaluated by using the InVEST model and related formulas. The difference comparison method was used to measure trade-offs and synergies relationships among ecosystem services. Then the spatial non-stationarity response of the trade-offs to influencing factors was explored through GWLR model. Finally, the trade-offs intensity among the ecosystem services of each township was calculated by using the PPF and the trade-offs intensity index, and township development strategies to enhance synergies had been formulated. The results showed: (1) The high-value areas of habitat quality, soil retention, and ecological leisure were all distributed in the areas with high vegetation coverage such as nature reserves, national forest parks, and forest farms, while the high-value areas of food production services were distributed in the Qinwangchuan Basin, Zhuanglang River and Wanchuan Basin and other areas with abundant water resources. (2) The spatial distribution pattern of trade-offs and synergies relatiionships among ecosystem services had heterogeneity. Among them, the habitat quality-food production, soil rentention-food production and habitat quality-ecological leisure services were mainly trade-offs in the whole study area, and the remaining services were mainly synergistic. (3) The relationships between ecosystem services trade-offs and influencing factors, including ≥0 °C accumulated temperature, DEM and construction land area proportion, were robust, and the response of trade-offs to ≥0 °C accumulated temperature and DEM was highly similar. (4) Based on the principle of superposition analysis method, the whole study area was divided into four types of areas: I (4 types of services coexistence), II (3 types of services coexistence), III (2 types of services coexistence) and IV (to develop at most one service). This study can provide certain scientific guidance for the optimization and governance of regional ecosystems and the synergic development of townships.