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机构地区:[1]云南财经大学国土资源与持续发展研究所,昆明650221 [2]云南省国土资源厅,昆明650224
出 处:《中国农学通报》2010年第22期338-343,共6页Chinese Agricultural Science Bulletin
基 金:国家自然科学基金资助项目"近八年退耕还林工程驱动下的云南不同地貌区土地利用变化及其生态效应研究"(40861014);云南省土地学会资助项目"云南省五大地貌区典型县土地利用变化调查研究"
摘 要:以滇东南喀斯特山区的文山县为例,分析其2000—2008年间退耕还林工程驱动下的土地利用变化状况。结果表明,近8年来,文山县土地利用变化基本特点表现为耕地、园地、林地及建设用地面积均有所增加,荒草地及裸地等未利用土地面积明显减少;退耕还林工程的成效较为明显,林地面积有所增加,部分陡坡耕地得以实现生态退耕,但也有部分良田好地被生态退耕而转为林地、园地和荒草地,且退耕总量主要是<25°缓坡耕地,与国家耕地保护政策显著不符。尤其应当看到的是,林地的增加量和增幅远远低于耕地的增加量和增幅。同时,一边实施生态退耕,一边又毁林开垦,且毁林开垦量明显大于生态退耕量的现象应当引起重视。Taking Wenshan county,a karst mountainous area in southeast Yunnan province,for example,this paper has analyzed its land use changes from 2000 to 2008 driven by the project of converting farmland to forest.The result showed that during the eight-year period,the land use changes in Wenshan county had the following characteristics:areas of farmland,garden plot,woodland,and construction land all in the increase and areas of the unused lands such as waste grassland and bare land in the obvious decrease.The project achieved some good results:woodland increased and some steep slope farmlands being ecologically converted.However,some good farmlands were also converted to woodland,garden plot,and waste grassland.The lands converted were mainly farmlands on gentle slopes at less than 25°,which did not comply with the national policy on farmland protection.What is noteworthy was that the amount and rate of increase of woodland are far lower than those of farmland.Meanwhile,we should also notice the phenomenon that while some farmland being ecologically converted,some woodland is transformed into farmland and the amount of the latter is obviously greater than the former.
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