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竹林是世界第二森林。我国是世界上竹子的中心产区之一,有竹林340多万公顷,竹材年产量约为500吨。占世界年总产量的三分之一,列世界首位,而尤以南方各省种类繁多、资源丰富集中。仅湖南省就有竹林56万公顷,占全国第二位;竹林总蓄积量8.9亿株,其中毛竹为8.678亿株。居全国首位。这些竹类再生能力强,生长迅速,成材期短,产量高,具有一次造林可永续利用的特点。 竹材具有良好的理化性能。以毛竹为例,其平均密度为810kg/m~3,上部竹材和竹壁外侧的力学强度大;一般情况下,其顺纹抗拉强度为180MPa,为杉木材的2.5倍左右,横纹抗压强度为60~80MPa,是杉木材的1.5倍左右;静曲强度为150~160MPa。其化学成份主要是纤维素、半纤维素和木素,其力学强度完全适合加工生产各类竹制品,是重要的工业原材料、由于竹资源集中,易采伐,竹材材性易满足生产工艺要求,且建厂投资少、见效快,因而竹类具有广阔的开发利用前景。
Bamboo forest is the second forest in the world. China is one of the world’s leading bamboo producing areas with more than 3.4 million hectares of bamboo and about 500 tons of bamboo annually. Accounting for one-third of the world’s total output in the first place in the world, especially in the southern provinces with a great variety of resources and abundant resources. There are 560,000 hectares of bamboo forests in Hunan alone, accounting for the second place in the country. The total volume of bamboo forests is 890 million, of which 8.678 million are bamboo. Ranking first in the country. These bamboo regeneration ability, rapid growth, short material life, high yield, with a sustainable use of afforestation features. Bamboo has good physical and chemical properties. Taking bamboo as an example, its average density is 810kg / m ~ 3, and the mechanical strength of the upper bamboo and the outer bamboo wall is large. Under normal circumstances, the tensile strength of the parallel grain is 180MPa and about 2.5 times of Chinese fir wood. The compressive strength is 60 ~ 80MPa, which is about 1.5 times of fir wood; the static buckling strength is 150 ~ 160MPa. Its chemical composition is mainly cellulose, hemicellulose and lignin, the mechanical strength is fully suitable for the processing of various types of bamboo products, is an important industrial raw materials, due to the concentration of bamboo resources, easy logging, bamboo material easily meet the production process requirements, And less investment in factories, quick, so bamboo has broad prospects for the development and utilization.