Abstract:
Background The Xiaoluan River Basin is an important part of the Beijing-Tianjin-Hebei water retention functional area. Finding out the spatiotemporal evolution patterns of water yield and water retention functions in the Xiaoluan River Basin can provide a scientific basis for water resource management and regional sustainable development.
Methods In this paper, based on the multi-source spatial datasets in 2000, 2010 and 2020, the InVEST model and spatial autocorrelation analysis were used to explore the spatio-temporal changes and spatial clustering patterns of water conservation functions under different land use types in Xiaoluan River basin.
Results 1) Shrublands, forest and grassland were the main land use types in study area, urban construction land continuously expanded while the sandy land significantly decreased, leading to a noticeable improvement in desertification conditions Over the past 20 years. 2) The annual average water yield of Xiaoluan River Basin in 2000, 2010 and 2020 was 0.425×108, 0.669×108 and 1.147×108 m3, respectively, and the annual average water retention was 0.035×108, 0.061×108 and 0.073×108 m3, respectively, both showing a steady increasing trend year by year. 3) The high-value areas of water yield and water retention in the basin gradually shifted from the Yudaokou pasture in the midstream to the forest land and shrublandsin the upstream and downstream, indicating that ecological degradation occurred in the midstream pasture. 4) The spatiotemporal variations of water yield and water retention function was obviously heterogeneous across different land use types, and the land types that contributed most to water retention were shrublands, forest land, and medium-coverage grassland.
Conclusions This study can provide constructive scientific suggestions for land use optimization and water retention protection improvement in the Xiaoluan River Basin.