科尔沁沙地范围确定及风沙地貌特征研究

科尔沁沙地范围的界定,目前尚未达成共识.本文利用Landsat8OLI影像和ASTER GDEM数据,采用水系流域分割方法,划定科尔沁沙地的自然地理范围.并提取了各类沙丘分布信息,对沙丘格局特征和形态示量做了定量研究.结果表明,科尔沁沙地面积64 387.22km2,风沙覆盖面积37 381.00km2.风沙地貌分布及格局具有一定规律性,沙丘类型自西向东、自南向北趋于简单,并主要分布在西辽河干、支流沿岸的冲积平原上,不同河谷形态、走向其两侧沙丘发育呈现差异性,河流对沙地发育演化及维持其平衡态具有重要意义.

Boundary delimitation and characteristics of aeolian sand landform in Horqin sandy land

The scope of Horqin sandy land has not been defined clearly.To solve this issue,segmentation derived from water basins was used to delimit natural geographical scope of Horqin sandy land based on Landsat 8OLI images and ASTER GDEM data.Further,after extracting distribution information of various sand dunes,quantitative analysis was carried out on dune pattern and morphology.The area of Horqin sandy land was found to be 64 387.22 km2,aeolian coverage was 37 381.00 km2.Some regularity in sand landform distribution and pattern was apparent.From west to east,from south to north,the main dune types distributed in the field of West Liaohe River and the alluvial plains tributaries tended to become simple and single.Distinct diversity was also found through different valley forms,trend and dune development on both sides of the river.In conclusion,river not only plays a crucial role in sand evolution and development,but also in maintaining its equilibrium condition.The study provides some scientific evidence for desertification control and comprehensive research in the area of Horqin sandy land.