Grassland cover and ecological service function changes in Shiyang River basin

Grassland ecosystem is susceptible to environmental change, it is of great significance to study the changes of grassland cover and ecosystem service function. Based on the remote sensing data and InVEST model, we taken the Shiyang River basin as the research area in this paper, and quantitatively estimated the service functions of grassland cover change, water yield, soil conservation and carbon sequestration service since 2000, and discussed the effects of grassland cover change on ecosystem service. The research results showed that the degradation of grassland cover in the Shiyang River basin was obvious during 2000–2015; the water yield of grassland was decreased first and then increased, and the service of soil conservation and carbon sequestration were decreased. There was a significant negative correlation between grassland coverage and water yield in the middle reaches of the river basin, and a negative (P < 0.001) correlation with the downstream soil retention while there was a significant (P < 0.001) positive correlation between the grassland coverage and other ecosystem services; the obvious vegetation degradation in the upper reaches of the Shiyang River basin gave rise to the decline of grassland ecosystem service capacity, so improve the quality of grassland ecosystem in the upper reaches have a great significance to advance the ecosystem service of the whole watershed.