The “Mountain-River-Forest-Cropland-Lake-Grassland System Project” has continuously improved the ecological environment of the region along the Yangtze River; however, there was little literature on quantitative analysis of the effects of the System Project. Ecosystem services value was first used to quantify the effects in the downtown Jiayu County and analyze the variation of ecosystem services value by the equivalent factor method between the 6 downtown Counties (Xianan, Chibi, Tongcheng, Chongyang, Tongshan, and Jiayu) of Xianning City along the Yangtze River for years 2000, 2010, and 2020. The results specify that: (1) The area of forest, grassland, wetland, and water body increased by 47.5%, 254%, 1165%, and 7.4% in downtown Jiayu, whereas the cropland and built-up decreased by 1.8% and 3.1%, respectively. (2)
The mean change rate of the ecosystem services value for the 6 ecosystems in downtown Jiayu and Tongcheng was 3801% and 41% from 2000 to 2020, respectively, while the mean change rate of the ecosystem services value was about −42% in other downtowns. (3) The rate of ecosystem services value for the ecosystem services in downtown Jiayu decreased about 13% in the first 10 years and 9.7% in the second 10 years, while the rate of ecosystem services value for the ecosystem services decreased about 40% in other downtowns from 2000 to 2020. (4) The maximum sensitivity coefficient is 0.381 for the cropland ecosystem and 0.185 for the water regulation services. The system project has a positive effect on the ecosystem services value, increasing and quickly restoring the ecosystem services value of downtown County. Besides, the local government of Jiayu might obtain corresponding socio-economic benefits through ecosystem services value transactions.