Analysis On The Ecosystem Services And Its Constraining Factors In Yunnan’s Basin-Mountain Complex Ecosystems

Mountainous cities account for more than 50% of total urban area in China.Accelerated process of urbanization in mountain area is facing the challenge of ecosystem service degradation.The changes and constraints of ecosystem services are critical and unignorable issues in the sustainable development of mountain cities.In this paper,the Basin-mountain complex ecosystems(BMCEs)composed of the Basin and its adjacent mountain areas in Yunnan Province were selected as the research units.Using the In VEST model and the ecological footprint method,the four ecosystem services(ES),i.e.habitat quality,water supply,soil conservation and carbon sequestration,as well as ecological carrying capacity(ECC)of BMCEs in1990,2000,2010,and 2020 were analyzed.The constraints of BMCEs’ ecosystem service were analyzed by the random forest model.In combination of ES and ECC,we evaluate the ecosystem service quality of BMCEs.The results were:(1)The habitat quality,soil conservation and carbon sequestration of BMCEs’ ecosystem services were mainly affected by social factors,and land use was the key driving force.Water supply was mainly affected by annual precipitation and humidity index.(2)ES and ECC increased significantly from 1990 to 2000,and then showed a downward trend.(3)With the increase of cultivated land area,habitat quality,water supply and soil retention capacity decreased.Carbon sequestration capacity increased with forest area.And ECC increases with elevation above the sea level.(4)ES’s quality of BMCEs inceased first than droped in the past 30 years.In 2020,the level of ecosystem service quality in central Yunnan was low,and the surrounding areas showed higher values in a concentric pattern.