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利用多时相的Landsat-TM数据和国家资源调查数据,对我国耕地动态变化和典型区的土地覆盖变化进行了研究,结果显示:我国耕地的分布向东北和西北推移,移动的结果导致耕地的生态背景质量下降。黄河河口的耕地和海岸带扩大,扩大的速度是0.73 kma-1,沉积速率是2.1 kma-1。 对科尔沁沙地的研究结果表明,该区沙化面积从70年代的60.02%上升到80年代的64.82%,但是90年代后沙化面积缩小为54.90%;对藏北的湖泊动态变化研究结果显示,湖泊的面积下降,下降的速度为2.14 km2a-1。
Using multi-temporal Landsat-TM data and national resource survey data, the dynamic changes of cultivated land in our country and the changes of land cover in typical areas are studied. The results show that the distribution of cultivated land in our country shifts to the northeast and the northwest, resulting in the ecological Background quality is declining. The arable land and coastline of the Yellow River Estuary expanded at an expansion rate of 0.73 kma-1 and a sedimentation rate of 2.1 kma-1. The results of the study on Horqin sandy land show that the area of desertification increased from 60.02% in the 1970s to 64.82% in the 1980s, but the desertification area decreased to 54.90% after the 1990s. The study on the dynamic changes of lakes in northern Tibet shows that lakes The area decreased, falling at a rate of 2.14 km2a-1.