Abstract: Wetlands in the Gansu section of the Heihe basin play a crucial strategic role in the national ecological construction. Under the stress of social and natural factors, it is extremely urgent to formulate a planning to protect the wetland resources in this area. Based on remote sensing images, this paper selects landscape fragmentation indexes to analyze the fragmentation process of wetland landscape in the study area, and adopts the Integrated Valuation of Environmental Services and Tradeoffs (InVEST) model to comprehensively evaluate the eco-environmental quality of wetland resources in the two periods of 2000-2008 and 2008-2016. Results show that in 2000-2008, the total area of the wetlands of different types in the study area decreased significantly with the largest decrease in shrub swamps. Since 2008, the total wetland area has been increasing. The degree of landscape fragmentation in the study area continued to be lowered in 2000-2008, but began to improve after that. The eco-environmental quality of the wetlands in the study area is generally good, and the area of extremely important habitat wetlands accounts for 86%-94% of the total wetland area.

Key words: InVEST model, landscape fragmentation, eco-environmental quality, Gansu section of Heihe River basin