1.College of Soil and Water Conservation,Beijing Forestry University;2.Key Laboratory of Soil Water Conservation and Desertification Control,Ministry of Education
Through the quantitative study of the relationship between land use change and ecosystem service value in the upper reaches of the Yellow River in the past 20 years, the comprehensive ecological management effect of the upper reaches of the Yellow River was evaluated, which provided a basis for improving the spatial planning, ecological environmental protection and management of ethnic regions, and promoted the high-quality development of the Yellow River Basin. Using the land use data of the Sichuan section of the upper reaches of the Yellow River in 2000, 2010 and 2020, the land use changes were analyzed based on the land use dynamics and land use matrix, and the economic value of the ecosystem service value equivalent in the Sichuan section of the upper reaches of the Yellow River was revised with reference to the equivalent ecosystem service value per unit area of the terrestrial ecosystem in China, and the impact of land use change on the ecosystem service value in the Sichuan section of the upper reaches of the Yellow River from 2000 to 2020 was quantitatively studied. The results show that: (1) From 2000 to 2020, the land use area of forestland, desert, wetland and water system in the upper reaches of the Yellow River in Sichuan showed an upward trend, while arable land, shrubs, grassland and glacial snow cover showed a downward trend, and the land use change in 2010-2020 was more significant than that in 2000-2010. (2) In 2000, 2010 and 2020, the value of ecosystem services in the Sichuan section of the upper reaches of the Yellow River was 1.27×1010 yuan, 2.51×1010 yuan and 3.92×1010 yuan, respectively, showing an upward trend, and sensitivity analysis showed that the analysis results were reliable. Among the land use types, grassland was the land with the most significant contribution to the total ecosystem value, with grassland ecological service contribution rates of 93.9% and 72.9% in 2000-2010 and 2010-2020, respectively, followed by wetland and forestland. (3) In the study area, the value of each individual ecosystem service showed an increasing trend in 20 years, and the sub-values of regional ecological service functions were all regulation services> support services> supply services > cultural services, and climate regulation, hydrological regulation, soil conservation and biodiversity were the most significant service values among the 11 individual functions, and the sum of the four accounted for more than 58.5% of the total value. Land use change in the upper reaches of the Yellow River in Sichuan will affect the change of regional ecosystem service value, with grassland having the most significant impact, followed by wetlands and forest lands. The results of ecological governance have gradually increased in the past 20 years, and the ecological environment has continuously improved.