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我省河西走廓的沙荒地区,解放后栽培和营造了大片沙枣林。这些沙枣林大部分生长良好。对防风固沙,改良气候,美化环境,保护和促进农牧业生产,解决群众燃料等方面,都起了重要作用。但有一部分生长不良,林分衰退,甚至成片死亡。究其原因,则主要有两个方面。一方面是环境条件太差,也就是土壤过于干旱,过于贫脊,盐碱含量过高,或病虫、牲畜、人为等危害过重。另一方面是密度过大。过密的林分限制了个
Hebei Province, the outline of the shortage of desert areas, after the liberation of cultivation and create a large sand jujube forest. Most of these jujube forests grow well. It plays an important role in windbreak and sand fixation, climate improvement, landscaping, protection and promotion of agriculture and animal husbandry production, and fuel for the masses. However, some grow poorly, the stand declines and even dies. The reason, there are two main aspects. On the one hand, environmental conditions are too poor, that is, the soil is too dry, too poor, too much saline, or pests, livestock, man-made and other hazards overweight. On the other hand, the density is too high. An over-limited forest limited