Southern Plateau Of Land Use Dynamic Change And Its Driving Mechanism

Land use change is a special kind of natural and social phenomenon, involving changes in natural attribute of land resources and human use patterns. This phenomenon is very obvious in the southern Loess Plateau. Driving mechanism of land-use change has been a focus of the land use change research. In recent years, with the development of RS technology, RS data has become an important data source which is used in space-time dynamic monitoring land-use change, Make land-use change in the dynamic process of monitoring studies to be an unprecedented progress. Although scholars have done a lot of research, it is necessary for researching the land use change in the southern Loess Plateau.This paper selected typical region of the southern Loess Plateau-Weibei Plateau as the object of study, selected the three TM images of 1990,2000,2007 year as data sources, analyzed the process of land use change in quantitative changes, spatial distribution, structure, speed, relative regional differences and land use degreee.On this basis, collecting socio-economic statistical indicators, the paper studied the human driving factors by the qualitative and quantitative method.Through this research, conclusions were as follows:(1)In the past 17 years, from 1990 to 2007, In the event of changes in land use, The trend of farmland, grassland, unused land, water was decreacing, and the trend of construction land, woodland was increacing. From the year of 1990 to 2000, the area change rate obeyed the following sequence:construction land (20.4%)> unused land(-17.5%)>water(1.79%)>woodland(1.71%)> cultivated land(-1.42%)>grassland (-0.76%). And from the year of 2000 to 2007, the sequence was woodland(19.40%)>unused land(-15.11%)>water(-11.89%)>construction land(8.90%)> grassland (-5.24%)>cultivated land(-4.37%).Cutivated land into construction land, cultivated land into woodland, and grassland into woodland were the main types of land use change.(2)Land use change existed obvious differences in spatial distribution.The type of cultivated land into construction land was mainly distributed in the tableland of the south of the Weibei plateau. And the type of cultivated land into wood land and grassland into woodland mainly distributed in the ecotone of hills and tableland of the north of Weibei Plateau.(3)In the year of 1990 to 2007,cultivated land, grassland, woodland were the main land-use structure in the Weibei Plateau, the proportion was 50.26%,26.29%,18.68%.(4)In the last 17 years,the speed of land-use change was rapid.From the year of 1990 to 2000.The integrated land-use dynamic degree was 0.1%.The single land-use dynamic degree obeyed the following sequence:construction land>unused land>water>woodland>cultivated land >grassland. From the year 2000 to 2007,the integrated land-use dynamic degree was 0.54%. The sequence of single land-use dynamic degree was woodland>unused land>water>construction land >grassland>cultivated land.(5)The relative rate of land-use change was different in the various regions of Weibei Plateau. From the year of 1990 to 2000, the relative rate of cultivated land obeyed the following sequence: Xianyang>Weinan>Baoji>Tongchuan; the sequence of woodland was Weinan>Xianyang >Tongchuan> Baoji; the grassland was Tongchuan>Weinan>Xianyang>Baoji; the water was Weinan>Tongchuan>Xianyang>Baoji; the construction land was Tongchuan>Weinan>Xianyang >Baoji. From the year of 2000 to 2007, the relative rate of cultivated land obeyed the following sequence:Tongchuan>Xianyang>Baoji>Weinan; the sequence of woodland was Xianyang> Baoji>Weinan>Tongchuan; the grassland was Xianyang> Baoji>Tongchuan>Weinan; the water was Tongchuan>Baoji>Xianyang>Weinan; the construction land was Weinan>Xianyang>Tongchuan >Baoji.(6)From the year of 1990 to 2000, the extent of land-use has been increasing in Weibei Plateau, and from 2000 to 2007,it has been started to reduce. By comparing, the comprehensive level of land use was higher in Xianyang and Weinan than other regions.(7)The main drive of change in the cultivated land is economic development, especially the development of tertiary increase, the increase of people's construction level and the population increase.(8)Policy, economic development, the level of agricultural in science, market factors and technology, population growth is the important land-use change drivers in Weibei Plateau. The land management policy and ecological policy is the dominant factor which played a role in the overall regulation and control.For the development of the area, water is the constraint.