论文部分内容阅读
我国是一个杨树大国,杨树品种、数量以及人工林面积都处于世界领先地位。我国24个省市区有杨树分布,原生杨树70多种,无性系近千个。杨树人工林总面积达700万公顷,居世界第一,超过了其他国家杨树人工林面积的总和。由于我国经济社会的快速发展对木材需求量日益增大以及天然林保护政策的实施,木材产量仍供不应求,而杨树具有生长快、成材早、产量高、用途广等特点,目前我国正在大面积推广,很多地
Our country is a poplar country. Poplar varieties, quantity and plantation area are in the leading position in the world. Poplar trees are distributed in 24 provinces and cities in our country, with more than 70 native poplar species and nearly a thousand clones. Poplar plantations a total area of 7,000,000 hectares, ranking first in the world, exceeding the sum of poplar plantations in other countries. Due to the rapid economic and social development of our country and the increasing demand for timber and the implementation of the natural forest protection policy, timber production is still in short supply, while poplar has the characteristics of fast growth, early harvest, high yield and wide use. At present, China is in large area Promote, a lot of ground