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引言 80年代中期,为了缓解木材的短缺,减轻木材生产对防护林等公益林的压力,中国政府决定用大约30年时间在全国范围内大面积营造人工用材林。这种做法很有必要,既可以保护现有森林,又有利于环境改善和生物多样性保护。从1987年以来,已经营造了2000万hm~2的人工用材林,这些人工林是以注重培育技术、集约管理和集中大量财力物力为基础的。近些年来,人工林以每年330万hm~2的速度增加。经过10年的时间,中国的人工林营造取得了举世关注的成绩。然而,由于连栽人工林所导致的地力衰退、生态恶化、森林生产力下降及病虫害
Introduction In the mid-1980s, in order to alleviate the shortage of timber and reduce the pressure on timber production from non-commercial forests such as shelterbelts, the Chinese government decided to build a large-scale artificial timber plantation nationwide in about 30 years. This approach is necessary to both protect existing forests and to improve the environment and biodiversity. Since 1987, 20 million hectares of artificial timber forests have been created, which are based on the cultivation of technologies, intensive management and the concentration of large amounts of financial and material resources. In recent years, plantation forests have increased at an annual rate of 3.3 million hm ~ 2. After 10 years, the success of plantation in China has won worldwide attention. However, the decline in soil fertility, ecological deterioration, decreased forest productivity and pests and diseases due to continuous plantation