Spatial Pattern Optimization Of Ecological Space Based On ESV And EF Model

After the reform and opening up,China’s development achievements have attracted worldwide attention.China’s urbanization rate grows at an average annual rate of 1 percentage point and GDP maintains an average annual growth rate of 10percentage points.However,the environmental problems have outbroken concentrately in China during the past 40 years.In particular,the smoggy weather that frequently erupted in recent years has accelerated the depletion of resources and environment of China,and damaged the dream of a better life for ordinary people.With the rapid progress of urbanization and the annual growth of more than 10 million urban populations,the rigid demand for land and natural resources in production and life is increasing rapidly,occupying a large number of forest land and other ecological land for real estate.The development and construction of commercial areas and industrial areas have had a negative impact on regional ecosystem service functions,resulting in more serious human-land conflicts and serious overload of regional land ecological carrying capacity.Therefore,how to optimize urban ecological space has become an important proposition and practical problem for regional sustainable development.In view of this,following the logical idea of“propose problem-analyze problem-solve problem”and the research framework of“theoretical analysis-empirical study-policy suggestion”,this thesis predicts and simulates the tempo-spatial evolution of ecological land in Xuzhou central area based on the land use status and the classification system of ecological land.The ecosystem service value and ecological footprint of Xuzhou central area are measured,and the minimum cumulative resistance model is alpplied to optimize the ecological space pattern.Based on the research results,the policy suggestions are proposed.The conclusions of this thesis are as follows:(1)The overall analysis shows,during the period of 2005-2015,the area of cultivated land,forestland and unutilized land in Xuzhou central area decreased,and the area of water area,built-up land and grassland area increased.In 2005-2010 and2010-2015,the change rate of the cultivated land and unutilized land changed from negative to positive,that of water area and grassland changed from positive to negative.The reduce rate of forestland accelerated,and the increase rate of built-up land slowed down.The comprehensive land use change degree of Xuzhou central area decreased during 2010-2015,which means the change speed of all land types decreased and land use was more stable than that of 2005-2010;(2)The spatio-temporal characteristic shows,the ecological land in Xuzhou central area is mainly concentrated in the north,east and northwest in 2005-2015,and the aided ecological land took a propotion of more than 80%.In terms of time,from2005 to 2015,the area of ecological land in Xuzhou central area showed a downward trend,with a total reduction area of 135.39km~2.Among the three types of ecological land,the area of functional ecological land increased,and the aided ecological land and backup ecological land reduced.According to the pattern simulation,it is estimated that by 2020,the area of ecological land in Xuzhou central area will be reduced by 32.30km~2compared with 2015,and the decline rate will be 1.36%.(3)The value calculation shows,in 2005,2010 and 2015,the standard value of ecosystem services in Xuzhou central area was 769.27,1064.83 and 1127.86 yuan/hm~2respectively,and the ecosystem service value of Xuzhou central area was 1.92×10~9,3.21×10~9 and 2.96×10~9 yuan respectively.In terms of the types of ecosystem services,the value of regulated service is the highest,while the value of supply services is negative;in terms of land use types,the ecosystem services provided by waters were the highest.From 2005 to 2014,the per capita ecological footprint and ecological deficit of Xuzhou central area were fluctuating.The per capita ecological footprint increased from 1.0617hm~2/person to 1.1718hm~2/person,and the per capita ecological deficit increased from-0.9613hm~2/person to-1.0854hm~2/person,and the per capita ecological carrying capacity decreased from 0.1004hm~2/person to 0.0865hm~2/person.(4)Spatial pattern shows,in 2005,2010 and 2015,the pattern of unit ecological service value in Xuzhou central area changed little.The unit ecological service value in southwest area was low and negative,which gradually expanded to the east;the high unit ecological service value took a small proportion and scattered in the northeast,southeast and southwest area;the unit ecological service value in the north and southeast parts was between 3 and 214 yuan.The spatial pattern of per capita ecological footprint in Xuzhou central area was obviously changed.In 2005,the overall per capita ecological footprint of Xuzhou central area was lower,and the per capita ecological footprint of the southwestern region was higher,ranging from 0.117 to 0.125hm~2/person.In 2010,the overall per capita ecological footprint of Xuzhou central area increased,and the per capita ecological footprint of the southwestern region increased significantly compared with 2005.In 2015,the per capita ecological footprint of the southwestern area decreased compared with 2010.(5)Space optimization shows,using the minimum cumulative resistance model,based on the ecosystem service value and ecological footprint and other resistance factors,the functional ecological land is used as the ecological sources to optimize the ecological space of Xuzhou central area.The results show that the first-level ecological space area is 511.79km~2,which increased 187km~2 comparing with the simulation result and is also superior in spatial distribution.Therefore,optimizing the ecological space based on ecosystem service value and ecological footprint can achieve better results and have guiding significance for urban development.On the policy proposal,Xuzhou central area should improve the ecological service value of urban land use,optimize the artificial water surface and wetland area,coordinate and rationally plan the ecological land use pattern,strengthen the protection of high ecological service value areas such as waters and forest land;control the growth of ecological footprint and improve land carrying capacity to reduce the ecological deficit and make rational use of the land;coordinate the coordinated development of the spatial structure of the city,increase the functional ecological land area and increase its proportion in the urban land area,and use the reserve ecological land to convert it into functional and aided ecological land;improve the ecological environmental protection system,accelerate the delineation and coordination of the ecological red line,and adhere to the road of sustainable development to ensure regional ecological security.