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出 处:《中南林业调查规划》2001年第1期1-9,共9页Central South Forest Inventory and Planning
摘 要:研究提出了组织通用性二元立木材积模型建模样本的理论和方法。通过 1 1个方案的对比试验表明 ,根据建模单元内可能出现的径阶分布范围 ,选取不少于 5个取样径阶 (其中最小和最大径阶必取 ) ,然后在每个取样径阶范围中 ,按高径比大、中、小取 30株样木 ,总样本量不少于 1 5 0株所构成的建模样本 ,是保证模型具有广泛适用性的高效样本 ,从而可以避免以往取样工作中的盲目性 ,大量节约不必要的无效取样量。这一理论和方法 。In this paper,the theory and method for collection of sample to be used for modeling of commonly used two-way tree volume model are presented.Based on comparison of 11 options,a best way for collection of sample is as follows:According to the diameter distribution range of the modeling unit possibly appeared in practice,not less than 5 diameter classes are selected at first, where the smallest and largeter classes must be included; Secondly, between the range of each selected diameter class, 30 sample trees are selected in accordance with large, middle, and small values of “ratio of height to diameter”.Then, the modeling Sample is kmly 150 Sample trees, but it is very effective. Thus,the blindess before in Collection of sample can be avoidable,and amount of ineffective sample trees can be reduced or avered. As for other commonly used mathematical models in forestry to be used for prediction or projection, the theory and method for collection of modeling sample are of universal significance.
关 键 词:通用性二元立木材积模型 样本组织 样本结构 建模
分 类 号:S758.6[农业科学—森林经理学] S758.1[农业科学—林学]
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