THE ADAPTIVE SIGNIFICANCE OF TREE HEIGHT
THE ADAPTIVE SIGNIFICANCE OF TREE HEIGHT
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DOI：
10.1086/285075
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发表时间：
1990-06-01
影响因子：
2.9
通讯作者：
KING, DA
中科院分区：
文献类型：
--
作者：
KING, DA
建立了三次生长的博弈论模型来评价高度生长的适应意义。该模型平衡了高度对光拦截的优势与高度相关的成本，例如增加维持呼吸，减少茎生长可用的能量。该模型预测了平均年龄林分树木的进化稳定策略（ESS）。这种ESS包括一个较长的高度生长周期，当树木达到理论盈亏平衡高度的87%时终止，此时茎的维护和根和叶的更新成本需要所有可用的光合作用，而没有任何光合作用用于木材生产。利用森林产量表数据对模型进行检验，结果表明：(1)平均年龄林分的平均大小树木遵循预测的ESS，直到达到其最大高度的70% ~ 90%；(2)高于平均水平的树木，其树干比预期的要厚，以承受不成比例的更大的上层树冠的风力；(3)正如预测的那样，在非常古老的林分中，高度增长可能停止；(4)身高增长似乎是逐渐停止而不是突然停止。模型中没有但可能有利于逐渐停止高度增长的特征包括上层冠层更大的风暴露和不可预测的环境变化。该模型在解释树木生长模式方面的普遍成功表明，对光线的竞争是树木生命形式进化和维持的主要因素。由此产生的进化稳定的生长模式最大限度地提高了个体的竞争能力，但由于与高度相关的成本，减少了老林分的集体木材产量。这一结果与其他关于个体选择与群体选择的分析一致，这些分析发现，个体选择的种群的生产率低于群体选择的种群。
A game-theoretical model of three growth is developed to evaluate the adaptive significance of height growth. The model balances the advantages of height for light interception against height-related costs, such as increased maintenance respiration, that reduce the energy available for stem growth. The model predicts an evolutionarily stable strategy (ESS) for trees of even-aged stands. This ESS consists of a prolonged interval of height growth that terminates when the trees reach 87% of the theorectical break-even height, at which stem maintenance and root and leaf renewal costs require all available photosynthate, leaving none for wood production. Tests of the model with data from forest yield tables indicate that (1) average-sized trees of even-aged stands follow the predicted ESS until reaching at least 70%-90% of their maximum height; (2) trees that are larger than average have thicker-than-expected trunks to withstand disproportionately greater wind forces in the upper canopy; (3) height growth may cease in very old stands, as predicted; and (4) height growth appears to cease gradually rather than suddenly. Features that are not in the model but might favor a gradual cessation of height growth include the greater wind exposure of the upper canpy and unpredictable environmental variation. The general success of the model in explaining patterns of tree growth suggests that competition for light is the primary factor responsible for the evolution and maintenance of the arboreal life form. The resulting evolutionarily stable growth pattern maximizes the competitive ability of the individual but reduces the collective wood production of older stands because of costs associated with height. This result is consistent with other analyses of individual versus group selection that have found productivity to be lower in individual-selected than in group-selected populations.