Trade-offs And Collaborative Research On Major Ecosystem Services In Sanjiangyuan Based On InVEST Model

The sanjiangyuan area of qinghai province is a very important ecological security barrier and water supply site in China.It is the most concentrated and ecologically sensitive area of biodiversity in high-altitude areas,and has great ecological significance in biodiversity protection,water supply and soil conserva tion in China.But in recent years,makes the region climate warming,glaciers,snow-capped mountains decreased year by year,further affect water supplyway makes the area of lakes,wetlands and marshes shrink or even disappear,and human unlimited production and business operation activities,makes the region environment is very fragile,degeneration of ecosystem is happened,ecosystem services are badly affected,to the region economy development and the human production and living has caused some negative effects,so the research of ecosystem services in this region is very urgent and necessary.Three-river source nature reserve was established in 2000,and then to comprehensively consider the factors such as availability of data,this paper use In VEST quantitative evaluation model of the 2000,2005,2010,2015,soil conservation,water conservation and habitat quality of spatial and temporal variations of ecosystem service function of main,and the different land use types in all kinds of ecosystem services were analyzed,and also USES the Matlab statistical mapping method based on pixels,the partial correlation of time and space scales for three kinds of services are studied,the relationship among In order to reveal the relationship between the main ecosystem services in the san jiangyuan area,based on the above research results,SOFM neural network was used to carry out the ecological zoning of the sanjiangyuan area,so as to provide decision support for the resource utilization and management of the nature reserve.The main conclusions are as follows:(1)From 2000 to 2015,the average annual soil retention in the sanjiangyuan area was 38.32 t·hm-2·yr-1,and decreased at a rate of 0.35 t·hm-2·yr-1over the years.The annual average water yield is 292.11 mm,and the annual increasing rate is 2.02mm·yr-1.The mean habitat quality index was 0.6,and the overall quality did not change much.(2)The region with higher soil conservation function in the sanjiangyuan region is located in the east and the south,the east mainly includes xinghai county-maqin county-gande county-jiuzhi county-banma county,the south mainly includes nangqian county-yushu county-zajdo county,the northwest area of the soil conservation capacity is weak;From theperspective of geographical space,maduo,dayi and other counties havethe highest water supply,followed by zado and nangqian counties,and the lowest water supply in zhiduo county and golmud city.The overallwater supply showed an increasing trend,and the increasing trend wasmore obvious in the eastern Yellow River source area,but the water supply in zhiduo county,qumalai county and other areas showed a decreasing trend.Secondly,the habitat quality of most areas in the sanjiangyuan region is at a good level,with the average regional quality index of 0.6,among which the habitat quality of zhiduo county,zado county and tanggulashan town ship has been improved.(3)The soil conservation and water conservation services in the whole sanjiang yuan area are mainly in the cooperative relationship,the habitat quality and water conservation are mainly in the cooperative relationship,and the habitat quality and soil are mainly in the balance relationship.In different land use types,the soil conservation quantity and habitat quality of forest land,wetland land,building land and bare land are more balanced in space,and the water yield and habitat quality,water yield and soil conservation quantity are more synergistic in space.Only cultivated land shows the balance between habitat quality and yield.Grassland presents a tradeoff between water yield and soil re tention.(4)By building a self-organizing mapping characteristics of the network(SOFM),based on the main ecosystem service function and the relationship between the evaluation result,the ecological division,partition results compared with the original,in order to guide the three-river source nature reserve of natural asset utilization and ecological environment construction,the three national park planning and construction to providethe reference.Quantitative evaluation of different space-time characteristics of ecosystem services,and study the relationship between ecosystem services,based on different ecosystem services and their spatial distribution characteristics,relationships between ecological zoning of SOFM neural network,optimization of regional land management and ecosystem services and the three-river source nature reserve of natural resource management and ecological system integrity protection have important guiding significance.