In this study

we assessed the ecosystem service value of the second stage project of soil and water conservation deployed in Guyuan area of the Ruhe watershed according to the characteristics of ecosystems.The market value method

cost-alternative method

shadow-engineering method and opportunity-cost approach were applied to five indicators including soil conservation

water source conservation

carbon fixation and oxygen release

air cleaning and biodiversity conservation.The results showed that the ecosystem service value has increased by 852.93 million yuan since the project launched five years ago.The service of maintaining and improving soil quality contributed most to the total ecosystem value

accounting for about 48.86%.The service of water conservation contributed 30.16%

while carbon fixation and oxygen release and the other two accounted for 14.96%

3.7% and 2.31%

respectively.It is clear that the soil and water conservation measures played a significant role in environmental protection and soil erosion control in the Ruhe watershed.