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本文采用遥感影像分析、野外实地调查与定点观测的手段对北京市农田的时空分布与风蚀基本特征进行了分析。结果表明:玉米留茬地和翻耕地是京郊主要的风蚀农田类型,其中留茬地在全市各地均有大面积分布,翻耕地主要分布在延庆盆地。近年来,北京市农田大幅减少,但作为主要风蚀农田类型的留茬地和翻耕地面积非但没有减少,甚至还有所增加。留茬地在3~5月中旬地表风蚀较强,耙平后的秋翻耕地风蚀期长达6个月,而不耙平的秋季翻耕仅在4月份风蚀较强。
In this paper, the temporal and spatial distribution of farmland in Beijing and the basic characteristics of wind erosion were analyzed using remote sensing image analysis, field survey and fixed point observation. The results showed that stubble field and tillage land were the main types of wind farmland in Beijing suburbs, of which stubble area was distributed widely in all parts of the city and tillage land mainly distributed in Yanqing basin. In recent years, the farmland in Beijing has decreased substantially, but the areas of stubble and tillage, which are the major types of wind farmland, have not only decreased but even increased. Stubble in the mid-March to mid May strong wind erosion, raking flat autumn tillage eroded up to 6 months, but not raking autumn tillage only strong wind erosion in April.