Spatiotemporal Variation Analysis of Water Yield Services in the Beijing-Tianjin-Hebei Region Using the InVEST Model

Calculating the water yield services in the Beijing-Tianjin-Hebei is indispensable for ensuring water resources security, optimizing resource allocation, maintaining ecological stability, and supporting ecological restoration. Against this background, this paper quantitatively studies the spatio-temporal dynamic change characteristics of the water yield in the Beijing-Tianjin-Hebei urban agglomeration from 2000 to 2023 by using the InVEST model. The results show that from a temporal scale, the overall trend of the interannual variation in the water yield depth in the Beijing-Tianjin-Hebei region from 2000 to 2023 is to increase first and then decrease, and the water yield depth in the study area was the largest in 2020. From a spatial scale, the spatial changes in the water yield services in the Beijing-Tianjin-Hebei region in different periods are relatively small, mainly presenting a spatial pattern with higher values in the northwest and lower values in the southeast. The supply of water yield services decreases as the altitude decreases. In this paper, suggestions are put forward according to the spatio-temporal characteristics of the water yield services in the Beijing-Tianjin-Hebei region: strengthening the ecological protection compensation mechanism and promoting the application of water-saving technologies.