Study On The Land Use And Land Cover Change And Its Driving Forces Based On RS And GIS

Research on land use/cover change and its driving forces is the key to the study of regional land use change. With the rapid development of social economy, the land use pattern is changing constantly, and the driving forces that affect the land use change are stronger and stronger. Setting the land use/cover change and its driving forces as the research content can supply a scientific basis for regional land sustainable use and rational planning in the future.This paper takes Jiangbei District as the research region. Firstly, getting the types’ area of land use and land cover on the basic of the remote sensing images of 6 periods; Secondly, the dynamic change features of Jiangbei’s land use and land cover are analysed from the year 2002 to the year 2013 by using the models dynamic degree of land use, comprehensive index of land use degree and landscape dominance of land use. Under the basic of what have been done, the concept of comprehensive index of land use and land cover general change is come up with and its model also has been constructed, and finally getting the comprehensive index of land use and land cover general change. And then, trying to use the may of ordinary curve-fitting and the way of comprehensive model to analyse and study the driving forces that affect the land use and land cover, and then comparing the driving results; Finally, putting forward the strategies and advance for Jiangbei’s sustainable land use. Research results are as follows:(1) By doing some preprocessing like geometry correction, radiometric calibration, image cropping and image enhancement on the remote-sensing images of six periods, using the way of supervised classification and unsupervised classification to interpret image data and doing a post classification processing on interpreting results, and finally interpreting six kinds of land types including cultivated land, forest land, rangeland, water area, unused land and built-up and associated land, and its interpretation accuracy reaches over 80%,which can meet the research standard.(2)The variable characteristics of Jiangbei’s land use and land cover from the year 2002 to the year 2013 are obvious. From the angle of quantity variation, the area of cultivated land, unused land and rangeland show a decreasing tendency year by year,and the area of construction land and forest land show a increasing tendency year by year, and the area of water area has little change. From the angle of single land use dynamic degree, the increasing change of construction land is fastest, and shows a pure increasing tendency; The decreasing rate of cultivated land is fastest, and shows a pure decreasing tendency. Comprehensive dynamic degree of land use shows a increasing tendency year by year, which states the disturbing degree that human act on land-use ways is increasing gradually. From the angle of degree change, the comprehensive index of land use degree shows a increasing tendency year by year, and both of its variable quantity and change rate are greater than zero, which states the comprehensive index of land use degree in Jinagbei is increasing gradually and the land-use in Jiangbei is in developing stage. From the angle of landscape change, landscape dominance shows two fastigiums and two trough periods, which state that the change of land use landscape pattern in Jiangbei fluctuates greatly. Landscape dominance increases gradually from the starting of 2009, which states that the difference of the proportion of land-use type in Jiangbei largen controlled by three kinds of land types construction land, forest land and cultivated land.(3)The concept of comprehensive index of land use and land cover general change is come up with firstly, and constructing the model of comprehensive index of land use and land cover general change, and the model is made up of three single aggregative indicators, comprehensive dynamic degree of land use, comprehensive land use degree index and landscape dominance of land use. Trying and finishing quantitative study on comprehensive index of land use and land cover general change, and this comprehensive index is calculated by using the method of variation coefficient on those three single aggregative indicators and weighting. The study results show that the change trend of comprehensive index of land use and land cover shows a trend of rising and sustainable growth, and rising rate becomes fast from the starting of 2009,which states that the comprehensive degree of land use development strengthens, and the level of land use and land cover general change improve continually.(4)Using conventional analysis method curve-fitting,analysing the thirty-three indicators that have an infuence on the change of land use degree,and finally getting thirteen indicators that have a good fitting degree with comprehensive index of land use degree, those indicators are as follows: urbanization rate, total population, gross domestic product per person, the total value in tertiary industry, per capita income of rural residents, gross fixed asset formation, the total value in secondary industry, total retail sales of consumer goods, savings balance of urban residents, per capita output of grain, agro-technician, per capita green area of public, green area in built-up area. Land use degree has a close correlation with those thirteen indicators, which states those thirteen indicators have a great influence on land use degree.(5) Aimming at the limitation of conventional analysis method curve-fitting, this paper use grey correlation analysis method, principal component analysis and multi-element linear regression to conduct a analysis on comprehensive model of driving forces. Getting ten driving indexs with high degree of association by using grey correlation analysis method: total industrial output value, the total value in secondary industry, savings balance of urban residents, per capita income of rural residents, gross domestic product per person, the total value in tertiary industry, total population, passenger volume, urbanization rate, emissions of industrial SO2,which states those 10 indicators have a great influence on the total level of the change of land use and land cover change. Getting the dominant factors that affect Jiangbei’s land use and land cover by using principal component analysis, the factors are social economy, transportation and ecological environment. The synthesis score of driving factors are increasing year by year from the year 2002 to the year 2013,which states that the synthetic action of those driving factors that affect Jiangbei’s land use and land cover is strengthening gradually, and comprehensive index of land use and land cover general change has a highly positive correlation with the synthesis score of driving factors; Using the way of multi-element linear regression to construct multiple linear regression model between comprehensive index of land use and land cover general change and driving factors, which can realize the quantitative evaluation on the total level of land use and land change.(6) There are some common and reasonable factors by comparing the analysis results of driving factors’ comprehensive model with the analysis results of conventional analysis method curve-fitting, which states the analysis results made by driving factors’ comprehensive model are scientifically rational and feasible. The comprehensive model can make the choice of driving factors of land use and land cover change more concise and concentrated, and it is suitable to actual circumstances for the extraction of driving factors, and successfully constructing the mathematical model between the total level of land use and land cover change and major driving factors by using the method of multi-element linear regression.(7) Under the basic of the study on the land use and land cover change and driving force and conbining the existing problems of Jiangbei’s land use, Jiangbei district should optimize the sustainable land use in the future from the aspects of population control, adjustment of industrial structure, cultivated land protection, economical and intensive use of construction land, the implement and revision of integrated land-use planning and harmonious development between land use and ecological environment.