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1 杨树人工林冻害的危害性杨树是我国北方主要栽植的速生树种之一。据1983年统计,全国有20个省、市、自治区发展杨树造林,保存面积约1亿亩。目前,各地区还在不断扩大栽培面积。黑龙江省不仅在西部地区栽植了大面积杨树人工林,在东部山区,为缓解森林资源的危机也营造了
A poplar plantation injury hazard of poplar is one of the main planting fast-growing tree species in northern China. According to the statistics of 1983, poplar afforestation was developed in 20 provinces, municipalities and autonomous regions across the country with an area of about 100 million mu. At present, each region is still expanding its cultivation area. Heilongjiang Province not only planted large-area poplar plantations in the western region, but also created the crisis in the eastern mountainous areas in order to ease the forest resources