Ecosystem Service Assessment And Influencing Factors Analysis Based Oninvest Model

On December 12,2009,the State Council officially approved the "Poyang Lake Ecological Economic Zone Plan",according to which,Poyang Lake Ecological Economic Zone will be built into a national demonstration area for comprehensive development of large lake basin,a water ecological safety guarantee area in the middle and lower reaches of Yangtze River,an important driving area to accelerate the rise of central China and an important platform for international ecological economic cooperation.Among them,Poyang Lake,as the largest freshwater lake in China,is an important ecological function protection zone in China,which takes on various ecological functions such as flood regulation and water storage,climate regulation and pollution degradation.In recent years,with the continuous development of social economy,industrial structure adjustment,increasing human activities and land use type transformation,etc.,coupled with the uneven distribution of rainfall,it has caused a series of ecosystem environmental problems in Poyang Lake eco-economic zone.Therefore,it is urgent to make reasonable assessment of ecosystem service function to provide decision basis for natural-economic-social sustainable development.Poyang Lake Ecological and Economic Zone has rich forest resources,which plays an important role in water connotation,carbon storage and soil conservation,but at the same time,Poyang Lake Ecological and Economic Zone is one of the most serious areas of soil erosion in the south,and the soil erosion in the upper reaches of five rivers has become increasingly serious for a long time due to unreasonable use of land resources,and the soil erosion in the lake area is also more serious,Poyang Lake Ecological and Economic Zone has rich forest resources forming It is a huge carbon pool.Nature is also the capital for human survival,and it is important to evaluate it accurately in order to make it serve human better.Based on the In VEST model,this thesis takes Poyang Lake Eco-Economic Zone as the research object,takes climate data,soil data,rainfall data and land use type data as the basis,firstly,the carbon storage,soil conservation and water conservation of Poyang Lake Eco-Economic Zone are statistically and quantitatively evaluated,then the significance of the factors influencing the ecosystem service is analyzed by geographic probe,and the factors influencing the ecosystem service most are determined.The most influential factors on ecosystem service function are land use type and slope,and finally the land transfer matrix and topographic position index are used to further analyze these two influencing factors.The results of the study showed that.(1)From the perspective of time,the water connotation function of Poyang Lake Ecological and Economic Zone shows a rising and then declining trend during1990-2020,and the soil conservation function shows a declining and then rising and then declining trend,and the decline is the largest from 2010 to 2020.The carbon storage function shows a decreasing trend year by year,but the decline is not big.(2)Spatially,the high value area of water connotation function is distributed in the southeast of Poyang Lake Ecological and Economic Zone,and the low value area is distributed in the northwest.Soil conservation function is mostly in the low value area.The low value area of carbon storage function is in the waters of Poyang Lake and its tributaries,and it gradually rises outward.(3)The results of spatial heterogeneity of ecosystem service function show that land use type and slope are the dominant factors affecting the ecosystem service function of Poyang Lake eco-economic zone.(4)Land use type is the dominant factor affecting the carbon storage function and water connotation function of Poyang Lake Eco-Economic Zone,among which,the water production capacity of arable land and man-made surface is the strongest,and the water production capacity of wetland is the lowest.The carbon storage capacity of forest land is the strongest,and the carbon storage capacity of water body is the weakest.Slope is the dominant factor affecting the soil conservation function of Poyang Lake Ecological and Economic Zone,and the soil conservation capacity shows a trend of rising and then falling with the increase of slope.