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中国是名副其实的杨树资源大国,全球共有杨树100余种,其中原产于我国的杨树就有74种。目前,我国杨树人工林面积已达700余万公顷,超过世界其他国家杨树人工林面积的总和,杨树胶合板出口居世界第一位。尽管我国杨树种植面积大、栽植株数多,但是,因为我国引进的品种在经过一段时间的繁育栽培后,品种优良性状衰退得比较厉害;再加上因为整形修剪等管理不规范,生产出的原木
China is truly a poplar resource country. There are over 100 poplar species in the world, of which there are 74 poplar species native to China. At present, the poplar plantation area in China has reached more than 7 million hectares, surpassing the sum of poplar plantations in other countries in the world. Poplar plywood exports rank the first place in the world. Despite the poplar planting area of our country, planting more plants, but because of the introduction of varieties in our country after a period of breeding, the fine varieties tragedy worse; plus because of plastic trim and other non-standard management to produce log