大青沟国家自然保护区土地利用与覆盖变化研究

Research on the Changes of Land Use and Cover in Daqingou National Nature Reserve

通过对“科尔沁草原大青沟自然保护区沙漠化程度图”的数字化处理以及相关社会、经济活动资料的收集整理，建立了大青沟及其附近地区土地利用与覆盖变化的地理信息系统数据库。同时，对１９５８年到１９８１年２０多年间该地区土地利用与覆盖的变化进行了分析。结果显示大青沟自然保护区内天然植被得到了很大程度的恢复，面积由１９５８年的４４６ｈｍ２增加到了１９８１年的６０９４ｈｍ２。人工林面积也有所增加。与此同时，大青沟保护区周边地区由于不合理的土地利用，引起了以沙漠化发生发展为显著特征的土地退化过程。流动沙丘面积和斑块数由１９５８年的９１６ｈｍ２和７０块增加到了１９８１年的９２２１ｈｍ２和３００块，半流动、半固定和固定沙丘的面积逐渐减少。在可识别的１６种土地类型中，其余土地类型的变化相对较小。值得注意的是该地区水体数量由１９５８年的５０个减少到了１９８１年的２５个左右，面积减少了７１ｈｍ２。在科尔沁沙地这样一个生态环境脆弱的地区建立自然保护区，而保护区附近地区的土地则发生严重退化，无论这种现象与保护区的建立有无关系。

Based on the digitized results of the three Desertification Maps of Daqingou Nature Reserve in Horqin Sandy Land and the data of related social and economic activities of this area, a Geographical Information System data set of the Nature Reserve has been set up for the convenience of further analysis in the future. Analysis of the above data showed that under protection, the natural forest cover in the Nature Reserve had been greatly restored with an area increase of 446 hm 2 in 1958 to 6 094 hm 2 in 1981, and the artificial wood land cover increased also. However, immediately outside the Nature Reserve, desertification had developed severely due to misuse of the land resource. Shifting dune cover and patch numbers increased from 916 hm 2 and 70 of 1958 to 9 221 hm 2 and 300 of 1981, respectively, while those of semi shifting, semi fixed and fixed dunes decreased. In addition to the above land use/cover changes of the rest were much less. Moreover, it is noticeable that the number of water bodies had been decreased from 50 of 1958 to about 25 of 1981, leading to an area decrease of 71 hm 2.