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矩阵模型在最优树种组成研究中的应用 被引量:5
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作者 李法胜 于政中 刘建国 《北京林业大学学报》 CAS CSCD 北大核心 1992年第2期23-30,共8页
对直径生长转移概率矩阵模型进行了线性扩展,用以研究混交异龄林的树种组成问题。以扩展后的矩阵模型为基础建立了考虑树种组成的最优经营模型,并以吉林省东部长白山林区针阔混交异龄林为对象,对模型进行了求解。结果显示作者所建立的... 对直径生长转移概率矩阵模型进行了线性扩展,用以研究混交异龄林的树种组成问题。以扩展后的矩阵模型为基础建立了考虑树种组成的最优经营模型,并以吉林省东部长白山林区针阔混交异龄林为对象,对模型进行了求解。结果显示作者所建立的模型同原模型一样具有直观性强、易于理解和应用的优点;特别是该模型在不增加问题复杂性的情况下,考虑了长期以来不易于定量化的最优树种组成问题。所得到的经营方案可供该地区制定经营决策时参考。 展开更多
关键词 良种树 应用 混交林 矩阵模型
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Principles and Practice of Forestation in Saline Soil in China 被引量:13
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作者 ZHANGJianfeng XINGShangjun +1 位作者 ZHANGXudong SUNQixiang 《Chinese Forestry Science and Technology》 2004年第2期66-70,共5页
With world population growth arable land area is decreasing. Saline soil is an important naturalresource. However it has not been well reclaimed owing to adverse conditions. Forestation is one way of saltysoil utiliza... With world population growth arable land area is decreasing. Saline soil is an important naturalresource. However it has not been well reclaimed owing to adverse conditions. Forestation is one way of saltysoil utilization; on the other hand, it can improve soil quality as well. The mechanism of salinity tolerance isthe basis for tree species selection when planting in salt affected soil. Different plants have various way ofsalinity tolerance, some are salt-exclusion, e.g. Elaeagnus angustifolia; some are salt-secretion, e.g. Tamarixspp.; some are salt-dilution, e.g. Hordeum vulgare; some are salt-avoidance, e.g. Rhizophora apiculata. Treesare favorable, which are salt tolerant and drought or waterlogging tolerant, as well as grow fast. After treespecies have been decided, site preparation including change or exchange of soil is necessary. Meanwhilesuitable density of trees and planting time must be carefully considered in terms of soil conditions andclimatic characteristics. Now a large scale of forests has been established in salt-affected soil in China by themeans discussed in the paper, and protect forest system along coast plays important roles in socio-economicsustainable development and improvement of eco-environment. 展开更多
关键词 saline soil forestation China
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