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天然林数量的减少以及质量的降低对中国的生态环境和经济发展产生不利影响。虽然林地的破碎对各种自然灾害起到关键性作用 ,林地是如何被破碎的尚不十分清楚。应用卫星遥感技术 ,以及地理信息系统和空间分析手段研究中国东北一原始的针阔混交林的破碎过程。结果表明 ,本来完整的原始森林 ,已经被一种“复叶”状小面积皆伐作业分割为零碎的斑块。采伐地的面积平均为 1 5 hm2 ,但随着采伐的继续 ,采伐地段连为一体 ,增大了采伐迹地的面积 ,从而保留的林地面积越来越小。采伐地点的选择没有考虑物种和环境的保护。林地破碎的特征是保留林地面积的缩小 ,中、小林地数量的增加 ,林地斑块形状的改变 ,以及林缘长度的增加。最后就保护东北森林植被完整性的角度提出林业政策与森林经营的改进意见
The reduction of the natural forest quantity and the decrease of the quality have a negative impact on the ecological environment and economic development of China. Although the fragmentation of woodland plays a key role in various natural disasters, it is not yet clear how woodland is broken. Using satellite remote sensing technology, GIS and spatial analysis methods to study the crushing process of a native coniferous and broad-leaved forest in northeastern China. The results show that the originally intact virgin forest has been divided into fragmented plaques by a “compound leaf” small-area clear-cut operation. The average area of harvested land is 15hm2, but with the continued logging, the harvested land is connected in one piece, increasing the area of the harvested land and thus keeping the area of forestland smaller and smaller. The choice of harvesting site does not take into account species and environmental protection. Broken woodland is characterized by a reduction in the area reserved for the forest, an increase in the number of medium and small woodlands, a change in the shape of the patch of forest land, and an increase in the length of the forest margin. Finally, we put forward the suggestions of improving forestry policy and forest management from the perspective of protecting the integrity of forest in Northeast China