The Use of Land Use Change Models to Support the Conversion of Unsustainable Dry Land into Forest Land or Grassland - A Case Study in Tongliao Region
基于土地利用变化模型的退耕还林还草决策分析 --以通辽地区为例

During the past decades, the rapid expansion of desertification has be come one of the most serious environmental problems in northern China.Northern C hina is a region sensitive to environmental change due to its transitional locat ion and the high potential for sandy deserti,fication.To mitigate the deteriorat ing eco,environmental conditions,the conversion of unsuitable dry land to forest land or grassland has been proposed as one of the major ecological programs by the Chinese government.To help the implementation of this program a new method t hat helps to identify suitable dry land for converting into forest land and gras sland is presented in this paper taking Tongliao region as a case.The regional l and use change model,CLUE,S,is used based on system theory to allow the integrat ed analysis of land use change in relation to socio,economic and biophysical dri ving factors.Land use change was simulated for Tongliao region from 2000 to 2010 .Then,suitable locations converting dry land into forest land and grassland were identified by overlapping the simulated land use change map of 2010 with a map showing the distribution of dry land in 2000,which was extracted from the land u se map of 2000.According to the result of the two overlapped maps,suitable locat ions for land conversion are mainly found in the central,the southern,and the ce ntral,northern parts of the study area.The central part of the study area,with r elatively high population density,is situated in the inland of Horqin Desert whe re desertification has always been very serious during the past decades.In order to mitigate the degradation of living environment,much unproductive dry land wi ll be reforested or converted to grassland in this sub,region.The southern and t he central,northern parts of the study area are more hilly and mountainous where soil erosion is very serious due to excessive reclamation.So,much dry land will also be chosen as the priority area for land conversion into forest land and gr assland in these two sub,regions.This paper illustrated that CLUE,S model is a u seful tool for implementing land management decisions,and that the results of th is study can provide valuable information for the conversion of unsustainable dr y land into forest land or grassland in the study area.