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四川红杉人工林林木分化结构的初步研究 被引量:3
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作者 周世强 黄金燕 《四川林业科技》 北大核心 1997年第2期33-36,共4页
四川红杉人工林林木分化结构的初步研究周世强,黄金燕(中国保护大熊描研究中心)林木分化是森林植物适应生态环境和林木之间生存竞争的结果,从而导致林分的自然稀疏,尽管森林经营的单位是林分,林学家还必须经常考虑单株林木的特点... 四川红杉人工林林木分化结构的初步研究周世强,黄金燕(中国保护大熊描研究中心)林木分化是森林植物适应生态环境和林木之间生存竞争的结果,从而导致林分的自然稀疏,尽管森林经营的单位是林分,林学家还必须经常考虑单株林木的特点来确定营林措施,如确定抚育间伐强度... 展开更多
关键词 红杉 四川红杉 人工林 林木分化结构
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Optimization models of stand structure and selective cutting cycle for large diameter trees of broadleaved forest in Changbai Mountain 被引量:6
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作者 郝清玉 周玉萍 +1 位作者 王立海 吴金卓 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第2期135-140,共6页
The optimum models of harvesting yield and net profits of large diameter trees for broadleaved forest were developed, of which include matrix growth sub-model, harvesting cost and wood price sub-models, based on the d... The optimum models of harvesting yield and net profits of large diameter trees for broadleaved forest were developed, of which include matrix growth sub-model, harvesting cost and wood price sub-models, based on the data from Hongshi Forestry Bureau, in Changbai Mountain region, Jilin Province, China. The data were measured in 232 permanent sample plots. With the data of permanent sample plots, the parameters of transition probability and ingrowth models were estimated, and some models were compared and partly modified. During the simulation of stand structure, four factors such as largest diameter residual tree (LDT), the ratio of the number of trees in a given diameter class to those in the next larger diameter class (q), residual basal area (RBA) and selective cutting cycle (C) were considered. The simulation results showed that the optimum stand structure parameters for large diameter trees are as follows: q is 1.2, LDT is 46cm, RBA is larger than 26 m^2 and selective cutting cycle time (C) is between 10 and 20 years. 展开更多
关键词 Large diameter tree Stand structure OPTIMIZATION Broad-leaved forest MODEL
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