中国新开垦耕地资源空间分布特征及生态背景研究

SPATIAL CHARACTERISTICS AND ECOLOGICAL BACKGROUND OF NEO-CULTIVATED LAND IN CHINA

该文在 90年代初至 90年代末期TM遥感图像获取的全国土地利用矢量数据基础上 ,提取新开垦耕地资源数据。利用ARC INFO的迭加功能将其与自然区划的地貌单元数据、坡度数据、降雨量数据及温度带数据迭加 ,分析了新开垦耕地资源的地理单元分布、坡度条件及水热条件。研究表明 ,新开垦耕地资源以草地、林地为主 ,主要位于东北平原及内蒙古草原地区。从降水条件来看 ,主要分布在湿润、干旱和半干旱区 ;从热量条件来看 ,主要分布在中温带和暖温带。耕地资源有向东北、西北偏移的趋势。在新开垦耕地中 ,同样存在坡耕地甚至陡坡耕地的问题 。

By interpreting TM images at the beginning and end of 1990s, the neo-cultivated land dataset are gotten. And then, it is overlaid with the topography, slope, precipitation and temporal datasets. Furthermore, the ecological background of neo-cultivated land is discussed. The results indicate that about 6.2×106 hm2 land was cultivated in 1990s, 55.69% of which was derived from grassland, 28.7% was from forest, 4.64% from seashore and water area, 10.82% was from unused land. With regard to the land converted from forest, 80.03% was located in Northern-eastern provinces and east of the Inner Mongolia Autonomous Region. As to the land converted from grassland, 72.65% was in the Inner Mongolia Autonomous Region, Heilongjiang and Xinjiang Uygur Autonomous Region. It is argued that what should be got much attention is that in the neo-cultivated land, 0.89% land whose slope are more than 25o are not favorable for farmland. It is further pointed out that most neo-cultivated land was located in humid area whose precipitation was 400～800 mm and nearly 77.93% neo-cultivated land located in middle-mild temperature areas.