Assessment of the ecological effectiveness of ecological conservation and restoration on the Qinghai Plateau from 2000 to 2020

China has embarked on various ecological initiatives to protect the ecological environment of the Qinghai Plateau, which have achieved positive results. However, ecological restoration is a long-term challenge, necessitating regular assessments of its progress. Such evaluations can provide both theoretical and practical guidance for future regional ecological management. This study developed an evaluation index system comprising six indicators across three ecosystem service categories: supporting, regulating, and provisioning services. Specifically, it proposed the Ecological Restoration Index (ERI) to quantify the ecological effectiveness of ecological conservation and restoration on the Qinghai Plateau from 2000 to 2020. The study also examined the relative contributions of climate factors and human activities to ecosystem changes. This study revealed significant spatial variations in ecological restoration across the Qinghai Plateau. Areas with more advanced ecological restoration were predominantly located in the eastern part, accounting for 60.62% of the plateau. In contrast, ecosystem degradation, which constituted only 2.07% of the plateau, was primarily concentrated in the northern Qaidam Basin. Furthermore, NDVI changes from 2000 to 2020 across 64.36% of the Qinghai Plateau were primarily attributed to climate factors, whereas 14.59% of the region was primarily attributed to human activities. In the future, the limiting effects of natural conditions should be fully considered when formulating strategies for managing the ecological environment through regional zoning. • The Ecological Restoration Index (ERI) was proposed. • Assessing the degree of ecological restoration of the Qinghai Plateau. • Ecological restoration exhibited significant spatial variation. • The contribution rate of climate factors in 64.36% of the study area was greater than that of human activities.