Research On Land Use Change And The Ecological Environment Response In The Urban Fringe

Land is the vital resource and material assurance for which humanity need to survive.And in certain regions,LUCC is the foundation of the PREE system(an open,dynamic and complicated system formed with population,resources,environment and economy).With economic development and wealth creation,land-use has serious impact on natural resources structure and ecological environment,and then influences the devolopment of economy as well.Since 1990s,as the most remarkable important feature of global change and the ideal penetration point of researches on nature or humanity process,land-use change is now attracting considerable attention by the circle of science and governments.Meanwile,the research contents are extended from the change of global climate to some other aspects,such as the changing process of land-use,driving mechanism,and environmental effects in different spatial scale spaces,etc.Among these,the environmental effects,micro mechanism and process are the focuses of LUCC research.Because of the vast territory,ways,structures and levels of land-use have different features in different areas.Therefore,taking the smaller and typical area as an example is the effective way to accomplish the further study on changing rules,driving forces and environmental effects of LUCC.Being the most complicated and dynamic region of a city,urban fringe has typical land-use changes and mechanisms which are different to neither the city nor the countryside.So,no matter from time angle or space,urban fringe is the natural laboratory and the best scale for LUCC research.To strengthen the research on LUCC and environmental effects of fringe areas has its great significance not only to the establishment of regional LUCC research foundation,but also can provide information and policy-making basis for related ministries to promote the development of economy,society and enviroment.Evidently change of land use brings greater influence on the environment in Jiangning district,the fringe area of Nanjing city which located in the eastern developed areas in China.Thus,it makes the district being the typical example for LUCC research.Based on the fundamental theories including the ecological economics theory,the sustainable development theory,man-earth relationship coordination theory,and system theory,this thesis analyzes the relationship between land-use and environmental effects in urban fringe,and takes Jiangning district as an example to make a detailed analysis on the changing process,the driving mechanism,and the ecological responses of LUCC.The main research contents and methods are as follows:First,the study gives some related concepts including city and countryside,suburb,rural-urban continuum,urban fringe,rural-urban fringe,clarifies why the paper uses the expression of "urban fringe";Second,based on the analysis of the characteristics and functions of land-use in urban fringe,the study shows the relationship and responsive mechanism between land-use change and ecological environment;Third,the study analyzes the dynamic changes of Jiangning district and reveals the basic features of land-use in fringe areas by bringing in some indexes and models of the changing range,speed,extent and effectiveness.Forth,based on the systematic statements of driving factors,and utilizing the method which combines qualitative analysis with statistic analysis,the paper analyzes the driving factors of Jiangning district's land-use change;Fifth,the paper studies the ecological environment response of land-use change in urban fringe in the aspect of magnitude of value(monetization),that is to say,based on the comparison among the three assessment methods of value of ecosystem service,the thesis analyzes how the land-use change in Jiangning district influences the value of ecosystem service based on the study of ecosystem value which was come up by Costanza and the modification of equivalent factors about ecosystem value in different areas of China posted by Xie Gaodi and the value coefficients.Sixth,the paper studies the ecological environmental response of land-use change in urban fringe in the aspect of amount of a substance(demonetization),in other words,based on the traditional ecological footprint model,the paper introduces the concept of "city hectare",constructs the computational methods of equilibrium factors and dynamic yield factors under the structure of city hectare model,and revises the ecological footprint of cultivated lands by multiple cropping index.And with the modified ecological footprint model,this paper gives a quantitative assessment to the land-use change in Jiangning district during 1996 to 2010.Seventh,based on the macro-structural adjustment and arrangement of land-use,the paper evaluates the ecological security of land-use change in urban fringe,namely,on the basis of systematic statement of concept,connotation,model frame and methods of evaluation relating to land ecological security,the paper assesses the LUCC security of Jiangning district from 2005 to 2010 with the matter element model.According to the above research contents,the paper obtains several conclusions as follows:(1)The relationship between land-use change and ecological environment is very close:on one hand,the ecological environment evolves gradually under the common influence of the two acting forces inside and outside the land ecological economic system;on the other hand,ecological environment can give restraint directly or indirectly to land-use change.(2)From 1996 to 2010,the land-use states in Jiangning district sharply changed.It shows that the cultivated land,water facilities lands and unutilized lands were decreased,while residential and independent mining lands,forestry lands were increased,and the other kind of lands had no evident changes,which were the main trend of land use changing in the last fifteen years;Also,the landscapes in Jiangning district have an apparent changes,which presented the increases of variety and evenness,the decrease of dominant degree,and reflects the increasing disturbance of human activities to the land-use in fringe areas.(3)The land-use change is mainly caused by factors like population growth,economic development,industrialization and urbanization,economic effectiveness difference between between cultivated lands and construction lands,etc.Population growth is the most dynamic driving force among them,and economy growth is the main factor.Industrialization and urbanization play an important role in the acceleration of land-use change.The difference of economic effectiveness between cultivated lands and construction lands lesds to the transfer from the former to the latter.In sum up,both the force of urban expansion and the force of internal interaction in fringe areas greatly influence LUCC in this district,which are the comparison of marginal effect among different land-use by different owners or users in essence.(4)From 1996 to 2010,the total value of ecosystem in Jiangning district tended to be decreased which mainly ascribes to the decline of cultivated land.In the fifteen years,the single ecosystem service value in different land-use patterns continuously reduced.The ecosystem service value of hydrology adjustion and waste disposal showed the largest decline.Only raw material supplies presented a stable growth.(5)From 1996 to 2010,both the ecological footprint and the ecological capacity in Jiangning district were decreased.Obviously,there had serious ecological deficit in those years.And the deficit was 75.42466×104hm2 which amounted to 722.47%of the total ecological capacity.The regional economy was facing severe ecological pressure because of the prominent contradiction between the social needs and the natural supply in Jiangning district.(6)After 2005,Jiangning district's land-use was wholely in safety because the environmental protection policies and measures taken by the government has achieved apparent ecological effects.However,the security level should be strengthened and improved.Among these factors,usage of agricultural chemicals,chemical fertilizer,and the SO2 discharge per unit area,the water resources per capita,green land the per capita,the qualified rate of industrial waste discharge,the net income of farmers per capita,the GDP per capita etc.,which contribute to the enhancement of ecological security,and the usage of cultivated land film per unit,the percentage of environmental governance investment of GDP,the proportion of tertiary industry's output value of GDP are the key elements for the security promotion.(7)Finally,the paper suggests that some measures should be taken,such as land-use planning enhancement,ecological land protection,land-use allocation model optimization,and ecological environment construction,so as to improve the relationship between land-use and ecological environment in urban fringe furtherly.