Spatial non-stationarity of water conservation services and landscape patterns in Erhai Lake Basin, China

Abstract

Understanding the relationship between water conservation service (WCS) and landscape patterns is important for ecosystem management and water resources regulation. However, existing studies on the relationship between water conservation services (WCS) and landscape pattern mainly focus on the impact of landscape composition on WCS, but ignore the spatial effects of landscape configuration. Taking the Erhai Lake Basin as an example, this study quantified the spatial and the temporal distribution of WCS and analyzed the changes in landscape composition and configuration from 1990 to 2020. Subsequently, the spatial non-stationarity between WCS and landscape pattern was discussed by using a geographically weighted regression model. The results showed that urban and forest landscapes increased by 3189.96% and 18.34%, while grassland, shrub, and cropland landscapes decreased by 21.30%, 20.65%, and 16.23%, respectively, from 1990 to 2020. The fragmentation degree of urban landscapes increased, while the fragmentation degree of other landscapes decreased. The fragmentation and the heterogeneity of the overall landscape decreased, while the aggregation increased. WCS increased by 15.82% from 1990 to 2020, it is mainly derived from forest landscape, which contributes more than 91% to WCS. The effects of landscape patterns on WCS were spatially heterogeneous. The mean patch density and largest patch index positively affected WCS in 66.80%–82.88% and 64.35%–72.42% of the regions, respectively, whereas the mean patch area negatively impacted WCS in 66.64%–82.41% of the regions. Decision makers can promote ecosystem management measures that are suitable for specific conditions based on the spatial differences of the effects of landscape patterns on WCS.