The Coupling And Feedback Relationship Between Land Use Change And Ecological Environment

Human economic activities constantly affect the surrounding environment through land resources.In this context,land use research has gradually become one of the important impetus in the relationship between human activities and ecological environment.On the one hand,land use change,especially the process of replacing the natural landscape pattern mainly consisting of vegetation and soil by the urban landscape pattern mainly consisting of artificial buildings,has resulted in a series of ecological environment problems,such as air pollution,soil degradation,urban heat island effect and reduction of biodiversity.On the other hand,with the increasing awareness and attention of human society to the above environmental problems,managers and decision makers will adjust land utilisation strategies independently according to the changes of ecological environment and ultimately affect land use change,which can be regarded as the restriction or influence of ecological environment on land use patterns.This interaction is the coupling and feedback relationship between land use change and ecological environment.However,the existing literature mainly focuses on the former which mainly refers to the ecological environment effects of land use change based on the analysis of land use classification and spatial and temporal evolution characteristics of land use change.However,the latter that is how ecological environment change affects land use change,especially the quantitative analysis of its impact mode,process and mechanism,has not been given enough attention and fully explained.Therefore,it is necessary to extend the study of the relationship between land use change and ecological environment from the single analysis to mutual coupling and feedback analysis.Therefore,taking Wuhan in Hubei Province as an example,this thesis analyses how land use change affects the ecological environment,and then attempts to explore how the ecological environment affects land use change.It can enrich the research on the coupling and feedback relationship between land use change and ecological environment.In addition,it can also provide scientific and reasonable suggestions for land managers and decision makers to make use of land resources and achieve sustainable development of land resources and ecosystems.This thesis mainly includes the two parts:(1)one is that the impact of land use change on the ecological environment.First of all,based on Landsat satellite data of 2000,2009 and 2018,the support vector machine supervised classification technique is used to extract land use information,and then the spatial and temporal evolution characteristics of land use in the study area from 2000 to 2018 are analyzed.Secondly,the atmospheric radiation transmission equation is used to retrieve the surface temperature and heat island intensity is divided into different levels to explore the impact of land use change,especially the expansion of construction land,on the urban thermal environment.Finally,the remote sensing ecological index of the study area is constructed from wetness,greenness,dryness and heat to evaluate the influence of land use change on the ecological environment quality.(2)The other is the impact of the ecological environment on land use change.Because it is difficult to quantify,this thesis attempts to quantify the impact of the ecological environment on land use by describing the dynamic adjustment of relevant land use policies.Specifically,word frequency analysis,co-occurrence analysis and multi-dimension analysis are adopted to dig the content of the national land use policy promulgated in China since 1986.Based on this,this thesis reveals the stages and characteristics of the evolution of land use policy in China.Then,the effectiveness of land use policy in Wuhan from 2009 to 2017 is evaluated by quantitative analysis model of policy from power,goal,measure and feedback.Finally,based on the time series data of ecological land area and construction land area in Wuhan from 2009 to 2017,the feedback effect of ecological environment change on land use change is analyzed.The results are as follows:(1)Cultivated land is the principal type of land in Wuhan,and land use in wuhan has changed greatly from 2000 to 2018.The analysis results of different periods show that compared with the period from 2009 to 2018,the speed and extent of land use structure change in Wuhan from 2000 to 2009 are relatively higher.The comprehensive degree of land use is on the rise.The spatial transfer direction of land use change is mainly from cultivated land and woodland to construction land and from water body to cultivated land.(2)There is a great difference in temperature between the central and surrounding areas of Wuhan in the summer from 2000 to 2018.The heat island effect in Wuhan is significant.The green island and the weak heat island are mainly distributed in the suburbs,while the medium,intense and strong heat island are mainly distributed in the central urban areas.The expansion of construction land is a major factor to enhance the urban heat island effect in Wuhan.(3)The remote sensing ecological index(RSEI)has increased from 2000 to 2018.The growth rate of RSEI from 2009 to 2018 is slower than that of RSEI from 2000 to 2009,which indicates that the ecological environment quality of Wuhan has been improved in 18 years,and the extent of improvement has been increased.The increase of woodland and cultivated land is one of the important factors for the improvement of ecological environment quality in Wuhan,while the expansion of construction land is one of the important reasons for the deterioration of ecological environment quality.(4)From 1986 to 2018,land use policies in China have evolved from simplicity to comprehensiveness,from dispersion to unity,and focuses more on the protection of the ecological environment.(5)The policy effectiveness of land use policies related to ecological land and construction land has changed greatly,and is closely related to the number and level of policies promulgated in that year.The cumulative policy effectiveness of ecological land and construction land has been gradually strengthened,and the reduction of ecological land and the approved area of construction land have declined year by year,which indicates that the implementation of relevant policies of ecological land and construction land in Wuhan from 2009 to 2018 has a good effect.Accordingly,this thesis puts forward the following policy recommendations.Firstly,Wuhan should change its economic development mode and avoid over-reliance on land ecological functions.Secondly,in order to promote the sustainable use of land resources,land use structure should be optimized.Thirdly,it is necessary to formulate land use planning scientifically and improve the capacity of developing and protecting geographical space continuously.Fourthly,the dynamic monitoring system of ecological environment should be built by using geographic information technology.Finally,the government should improve the policy system of land use and actively promote the legalization construction on land resources.