Study On Regional Land Use Change And Its Influence On Ecological Security

Land is a very precious natural resources, material base of human survival and development. The development of human society can not be separated from the land use and transformation, and this relationship between land and human is the most basic relations of production throughout the development history of human society. Land use by human has existed in the primitive society. In recent decades, land use intensity increased and the extent of land use has been achieved the regional ecological carrying capacity of land with the rapid growth of the world's population and the scientific level, resulting in the deterioration of the regional ecological environment.Over-exploitation of land resources, cultivation on steep slopes, large-scale deforestation,over grazing pasture,industrial pollution, over-concentration of urban congestion and so on, will give rise to the serious ecological crisis and even to causing the degradation of ecosystems. The Influence on ecological security by Land-use change on has become an important aspect in a national and regional ecological security. Land use change as one of the main driving force in the global environment change, this view has been generally recognized by scholars from all walks of life. In 1995, the International Geosphere-Biosphere program (IGBP) and the international human dimensions of global environmental change program (IHDP) co-launched the "land use/cover change research" program and included the core components of their own. Land use/cover change and ecological security has become cutting-edge research topics of land resources sustainable use with an extremely important significance.Based on the above consideration,this paper,supported by theories of sustainable development,system science, ecological economic, man-land relationship,adopts research methods such as theoretical & empirical research qualitative &quantitative analysis, multidisciplinary combining theory etc., implements research on land use change and its influence on ecological security. The main content of the statements and conclusions are as follows:First, research on the dynamic land use changes.Based on the theoretical contents, this paper analyses the main characteristics, manifestations of land use change and basic law.And it analyses land use changes in the number, structural and regional differences with the spatial and temporal evolution of model. The result shows that, in Jiangsu Province arable land, pasture and water have been decreasing and garden land,forest land, residential and industrial land, traffic land and unutilized land have been increasing from land use change in the number and structural. In addition, the information entropy of land use structure has been increasing dividing into two different stages. And It has been significant regional differences in land use changes. The type of land use in the biggest difference is garden land followed by pasture and forest land,while the smallest difference in traffic land.Second, research on the driving factors and mechanism in land use change. According to systematic classification approach, the paper analyses the driving factors of natural, socio-economic, land use policy on the driving mechanisms in land use change.And it has been empirical research by principal component and stepwise regression analysis. The result shows that, the socio-economic driving force is the main driving factor, including population growth, economic growth and technological progress, to a large extent affecting the dynamic changes of land use. The cumulative contribution rate of the two main components reach 95.63% according to the principal component analysis.From the stepwise regression analysis, there are negative correlations between the changes in the area of arable land and the total retail sales of consumer goods, the non-farm economy, the amount of highway passengerand positive correlations between the changes in the area of arable land and the total power of agricultural machinery.The investment of social fixed assets is the greatest impact of the changes in the area of garden land, followed by the total power of agricultural machinery. Changes in pasture and the non-farm economy is negative correlation. The changes in residential and industrial area and GDP, the total retail sales of consumer goods and financial income are related. GDP is the greatest impact of the changes in traffic land,followed by retail sales of consumer goods, and finally the amount of highway passenger.Third, the impacts on the ecological security by the land use changes are researched. According to the systems theory, landscape ecology theory and ecological economics theory, the framework and the mechanism that regional land-use change impact on ecological security are quantitatively analysized from the view of 5 microscopic ecological factors and macro-ecosystem point. The mode of action and the specific process that the land use changes impact on the ecological factors include:impacts on the climate through the feedback mechanism of biophysical and biogeochemical; the impacts on the water resources mainly include three aspects:the quantity of water, quality of water and spatial distribution of water; the impacts on soil mainly include:changes in soil physical and chemical properties, soil nutrient movement, changes in soil microorganisms and soil organic carbon changes; the impacts on landforms and geology mainly include the changes of landforms and geology, land subsidence and geological disasters; the impacts on biological diversity mainly include the changes of species habitat, and the changes of species and the relationship between species and environment. Land-use changes have a significant impact on the ecosystem structure and function in the macro level.Fourth, research on the evaluation of the land ecological security. The paper selects 18 indicators during natural, economic and social aspects and builds an index system of land ecological security assessment. Then it builds grading standard of indexes for land ecological security assessment according to different angles and dimensions. And it evaluates the state of land ecological security in Jiangsu province by unascertained measure model. The result shows that, the state of land ecological security appears fluctuations from 1996 to 2007 and in the whole belongs to the range of critical security and its evaluation scores increase slightly. The overall trend of land ecological security mainly causes by the changes of economic factors and social factors subsystem. The state of economic factors subsystem of ecological security fluctuates between security and.And It appears a gradual upward trend and its scores is up from 3.0792 to 4.1304. The state of social factors subsystem of ecological security is insecurity in addition to 1999. It appears a slightly downward trend and its scores is down from 2.6807 to the 2.2900.Fifth, the control on the land use based on the ecological security is studied. From the connotation, objectives, basic principles, control mechanisms, control mode and control the means of control, land-use regulation based on ecological security is carried out theoretical analysis. The control on the land use based on the ecological security is that in the background of market economy, the government effectively guide and control the ecological problems urged in the land use control process according to the inherent requirement of the land self-feedback mechanism, the land market mechanisms and the government mechanism for the land in order to regional natural, economic and social harmonious development. The guidance and control should be follow the 5 basic principles: the continuity, coordination, and stage, complement each other and interoperability, carried out by planning means, economic means, legal means, administrative means and technical means and adopted 3 levels models:macro, meso and micro models.In the end, the conclusion of the study to make specific policy recommendations:(1) Develop the policies for the protection of arable land and improve the productivity of cultivated land;(2) Implant the eco-construction projects, improve the status quo of soil erosion;(3) use the eco-industrial technology, reduce the use of pesticides and chemical fertilizers;(4) Control the industrial "three wastes", improve the land ecological environment;(5) Control population growth, ease the contradiction between people and land;(6) Increase the input of ecological construction land, the establish an ecological compensation mechanism;(7) Establishment the ecological function zoning of land, implement the ecological protection planning of land.