Abstract:[Objective] The impacts of ecological restoration in the middle reaches of Yellow River on water resources were studied in order to provide a scientific basis for the eco-environment protection and high-quality development of the basin.[Methods] Based on the GIMMS NDVI, ET, soil moisture, surface runoff and other hydrology data, the study used trend analysis and double cumulative curve methods to analyze the spatial and temporal characteristics of the evapotranspiration, soil water and surface runoff in the middle reaches of Yellow River, before and after ecological restoration.[Results] From 1982 to 2018, the fractional vegetation cover of the middle reaches of Yellow River increased by 29.72%. As the fractional vegetation cover increased by 1%, the evapotranspiration increased by 3~4 mm. In the ecological restoration area, the decline rate of soil moisture was 0.001 3% per year. The average runoff was decreasing from 1961 to 2018, and human activities represented by ecological restoration played an important role in the decline of runoff.[Conclusion] Due to the climate warming and drying and ecological restoration, there is a serious shortage of water resources in the middle reaches of Yellow River. People should consider water resources comprehensively, reduce human interference, and focus on natural vegetation restoration in the follow-up ecological restoration.

Abstract:In the middle reaches of Yellow river basin, a lot of projects have been built.Human activities have changed the land surface and erosion process, they have also alleviated erosion intensity and retained runoff and sediment. Isograms of sediment transportation modulus and coarse sediment modulus are drawn up based on the obtained data. The variation law of sediment and coarse sediment transportation modulus at areas with more and coarse sediment was analysed.