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在树木分类上,全世界共有125种杨树,我国就有50多种,几乎占了一半。在栽植面积上,全世界杨树人工林面积总计400多万公顷。我国已达300多万公顷,超过了其他国家杨树人工林面积的总和。就木材生长速度而言,速生杨一般每年每公顷蓄积量达到9-15立方米,最高可达30-45立方米;一般5-10年可采伐,每公顷蓄积量150-240立方米,可出木材105-165立方米,而其他树种的用材林15-18年生每公顷蓄积量仅达45-75立方米。山东临沂地区6年生杨树每公顷蓄积量最高达293.55立方
In tree classification, the world a total of 125 kinds of poplar, there are more than 50 kinds of our country, accounting for almost half. In planted area, poplar plantations around the world a total of more than 400 million hectares. Our country has reached over 3 million hectares, surpassing the sum of poplar plantations in other countries. In terms of wood growth rate, poplar generally accumulates 9-15 cubic meters per hectare per year, up to 30-45 cubic meters; generally 5-10 years harvestable, 150-240 cubic meters per hectare reserves, Timber 105-165 cubic meters, while other species of timber 15-18 years old, only 45-75 cubic meters of accumulation per hectare. 6-year-old poplar in Linyi, Shandong Province, up to 293.55 cubic meters per hectare