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在野外考察基础上对1966年地形图和1977年、1994年、2001年、2006年遥感影像进行目视解译,并以沙丘面积增加/减少数量、沙丘面积年均增长率、沙丘分布重心等指标来分析1966—2006年间沙丘时空变化。结果显示,沙丘扩张,分布重心向东南偏移。沙丘扩张主要源于沙源扩展,包括河漫滩与江心洲出露面积增加、草地退化沙质土壤出露、湖泊干涸湖底裸露、沼泽疏干。气象数据与人文统计数据分析表明,沙源扩展与近年来气温升高、降水减少、人口增长、牲畜增加有关。沙丘分布重心向东南偏移是因为起沙风主导风向为西风、北风及西北风。
Based on the field investigation, the topographical maps of 1966 and remote sensing images of 1977, 1994, 2001 and 2006 were visually interpreted. Based on the increase / decrease of dune area, the average annual growth rate of dune area, the center of gravity distribution of dune Indicators to analyze the spatial and temporal changes of sand dunes from 1966 to 2006. The results show that the sand dunes expand and the center of gravity shifts to the southeast. Dune expansion mainly due to the expansion of sand, including river floodplain and Jiang Xinzhou exposed area increased, grassland degenerated sandy soil exposed lake lakes bare, swamp dewatering. The analysis of meteorological data and human statistics shows that the expansion of sand source is related to the increase of temperature, the decrease of precipitation, the population growth and the increase of livestock in recent years. Dune center of gravity shift to the southeast because of the main wind direction of the sandstorm is westerly, north wind and northwest wind.