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

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

通过综合考虑影响退耕还林还草的自然和社会因素,结合土地利用规划和遥感影像解译结果,论文以通辽地区为例,介绍了利用土地利用变化模型确定退耕还林还草区域的方法和过程。根据对2010年模型模拟结果和2000年通辽地区土地利用现状的对比分析,结果发现2000～2010年该地区进行退耕还林还草的合适区域应该主要位于研究地区的中部、南部,以及北中部。研究地区中部属于科尔沁沙地的腹地,土地沙漠化最为严重,同时城镇和农村居民点分布较密,退耕还林还草是政府用于减缓风沙对城镇和农村居民点危害程度的重要生态措施;而南部和北中部属于丘陵和山区,由于过度开垦,水土流失较为严重,是实施退耕还林还草的重点区域。此外,与退耕还林区相比,退耕还草区距城镇、农村居民点以及道路相对较远,具有可达性较差、地理位置较为偏僻的特点。论文得出的结果可为今后通辽地区退耕还林还草工程的实施提供科学依据,同时,该文提出的确定退耕还林还草区域的方法对其它地区具有一定的借鉴意义。

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.