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众所周知,森工企业的可采森林资源,急剧减少,为解决这个问题,加快了人工林发展步伐,特别是加大了速生丰产林营造比重.但是,随着人工林增加,地力衰退也就日益明显.当前如何持久地维持人工林高的生产力,防止地力衰退,已成为林业界普遍关切的问题.据绥棱林业局调查,1970年营造的落叶松人工林,生长率由幼龄林时期的22.9%,锐减到5.6%,公顷生长量仅在5—6m之间.据东北林业大学造林研究所调查结果表明,北方营造的长白落叶松人工林、地力下降明显,在好、中、差三种立地类上,林分平均高的下降速率依次为12.7%、23.3%和29.0%.人工林地力衰退,不单单是技术性问题,很大程度是管理上的原因.
As we all know, forestry enterprises recoverable forest resources, a drastic reduction in order to solve this problem, accelerating the pace of development of plantations, especially to increase the proportion of fast-growing high-yield forest .However, as plantation increases, the decline of the soil is also increasingly Obviously, how to sustain the high productivity of plantations and prevent the decline of soil fertility at present has become a common concern in the forestry industry.According to the survey conducted by Suailian Forestry Bureau, the growth rate of larch plantations built in 1970 was changed from young period 22.9%, dropped sharply to 5.6%, hectare growth of only 5-6m. According to the Institute of Forestry, Northeast Forestry University survey results show that the north to create long-staphyonolamiculture plantations, significantly decreased soil fertility, good, On the three sites, the average high rate of decline of the stands was 12.7%, 23.3% and 29.0%, respectively. The decline of plantation productivity was not only a technical one but also a management reason.