Research On The Evaluation Of Ecosystem Services In The Yangtze River Delta And Its Value Realization Mechanism

Ecosystems provide human society with necessary production and living products and various ecological services.These products and services are called ecological products or ecosystem services.The foundation of the sustainable development of human society and economy lies in having a sustainable supply of ecological products.For a long time,due to the lack of understanding of the importance of ecological products and the lack of attention to the value of ecological products,the ecosystem has been severely damaged,and this damage has gradually threatened the sustainable development of human society.The degradation of the ecosystem urgently needs certain measures to alleviate,and the function of the ecosystem also needs to be further restored and protected.When striving to improve the supply level of ecosystems to products,it is necessary to evaluate ecosystem services,explore and practice effective paths to realize the value of ecological products.This is of great significance for the management of ecosystem services and the formulation of strategies for realizing the value of ecological products.This study firstly evaluated three ecosystem services in the Yangtze River Delta region.Using the spatial analysis method of Arc GIS platform,and taking the remote sensing data of 2000,2005,2010 and 2015 as the entry point.The land use changes in the Yangtze River Delta region were analyzed,including the area changes,spatial distribution characteristics and mutual transformation characteristics of the six land use types after reclassification.Then,with the help of the three modules of carbon storage,water production and soil conservation in the In VEST model,t the material quality and value of carbon storage services,soil conservation services and water conservation services that can be provided by ecosystems in the Yangtze River Delta region are evaluated.Its characteristics in time variation and spatial distribution are analyzed.Based on the evaluation of ecosystem services,this study proposes to invest in ecological infrastructure to realize the value of ecological products.Ecological infrastructure construction can change the behavior and quantity of ecosystem services provided,and market clearing can understand the value and scale of ecosystem services.Therefore,it is necessary to evaluate the potential of services after ecological infrastructure construction and predict market clearing equilibrium result.When exploring the value realization mechanism of market-oriented ecological products,this study selects Lu’an City,Anhui Province as a case area,comprehensively uses ecological and economic methods,and innovatively proposes to invest in farmland water-saving irrigation infrastructure to realize the value of water ecological products.First,the demand for water ecological products of industrial enterprises in Lu’an City was calculated through the C-D production function.Then,with the help of the water production module of the In VEST model and the water-saving potential model of farmland water-saving irrigation,the supply of water ecological products was estimated.Finally,under the guidance of cost-benefit analysis and market equilibrium theory,the market clearing state is analyzed,the scale of farmland water-saving irrigation infrastructure investment and the value of water ecological products are clarified.Research indicates:(1)In terms of land use change:among the six land types in the Yangtze River Delta from2000 to 2015,construction land increased the most.Judging from the area change rate of a single land type,the circulation of unused land is the fastest.From the overall land type change rate,it can be found that the change of land use in the study area is relatively slow,which is affected by the mature economic and social development of the Yangtze River Delta.The transformation of different land use types is fierce.Among them,the expansion of construction land is the most obvious,and cultivated land,forest land and water bodies are the main sources of expansion.(2)In terms of temporal and spatial changes in carbon storage quality and value:spatially,carbon storage presents a pattern of“low in the north and high in the south”,and there is no obvious concentration area for carbon storage changes in the entire study area.The carbon storage showed a decreasing trend year by year,and the areas with reduced carbon storage are mainly Shanghai,southern Jiangsu and northern Zhejiang.In addition,the carbon storage in the central part of Anhui Province also decreased significantly.Throughout the study period,the reduction of carbon storage showed a spatial pattern of"more in the east and less in the west".In addition,the carbon storage value of cultivated,forest,building land,water body,grassland and unused land decreases in order from high to low.This is not only related to the carbon storage per unit area of each land type,but also to its total area.(3)In terms of temporal and spatial changes in the material and value of soil conservation services:In the past 15 years,the soil conservation amount has"increased first and then decreased",but the overall trend is increasing,and the soil conservation capacity has improved.Spatially,soil conservation showed a distribution pattern of"more in the south and less in the north".The high values of soil conservation per unit grid were mainly concentrated in the southern region,and the low values were mainly in northern Anhui,Jiangsu Province and Shanghai.From 2000 to 2015,the areas with increased soil conservation were mainly in southern Zhejiang and western Anhui,while the areas with decreased soil conservation were mainly distributed in western Zhejiang and southern Anhui.The area of increased soil conservation was much larger than the area of decreased soil conservation.In addition,among the six land types,forest land has the greatest effect on soil conservation,and the soil conservation effect of cultivated land,grassland,construction land,water body,and unused land decreases sequentially,and the soil conservation value is ranked in the same order.In terms of time,the total soil conservation value of each category reached the highest value in 2010.During the whole study period,the change of soil conservation value in the Yangtze River Delta showed a trend of"decrease-increase-decrease".(4)In terms of changes in the quality and value of water source conservation over time and space:the water source conservation quantity shows an increasing trend year by year.The spatial distribution of water conservation capacity presents a pattern of"high in the south and low in the north".Most of the areas with high water conservation are located in southern Zhejiang Province and Southwestern Anhui Province.In the past 15 years,the areas with increased water conservation were mainly distributed in the central and northeastern regions of the Yangtze River Delta,and the area of increased water conservation was significantly larger than the area of decreased water conservation.Among the six land types,the water conservation of forest land and cultivated land is always much higher than that of other land types.In terms of time,the water conservation amount of grassland and other land types did not change significantly,and the water conservation capacity was relatively stable.The water conservation value of the first five years and the last five years did not change significantly.In the middle five years,the water conservation value of cultivated land decreased significantly,while the water conservation value of forest land increased significantly.(5)In terms of the feasibility of investing in ecological infrastructure to realize the value of ecological products:For industrial enterprises in Anhui Province,the marginal benefit of water is about 44.39 yuan/m~3.Among the land use of the villages in Lu’an City,Anhui Province,only52 villages have arable land and the area of arable land is less than 50%,while the area of water body is greater than 20%.After the implementation of the high-efficiency water-saving irrigation project,about 2.7863 billion m~3 of water resources can be saved,and the total amount of tradable water is about 3.0048 billion m~3.Through the cost-benefit analysis of high-efficiency water-saving irrigation projects,the profit after participating in water-saving irrigation is at least 30%higher than maintaining the status quo.The equilibrium result of market clearing is:19 villages in Lu’an City participate in water rights trading,the market equilibrium price is about 1.76yuan/m~3,and the traded water volume is about 1.667 billion m~3.After industrial enterprises buy water,the output value can reach about 1.37 times of the current stage.It is feasible to invest in the construction of ecological infrastructure.