Key messageTrees with otherwise equal dimensions have different leaf areas if they are located in different stand types. While leaf area of European larch is affected by mixture proportion, leaf area of Norway spruce is affected by stand density.ContextLeaf area is a key parameter for evaluating growth efficiency of trees, and therefore needs to be measured as consistently and accurately as possible. This is even more important when comparing monospecific and mixed stands.AimsThe aim of the study is to find combinations of parameters and allometric relationships that can be used to estimate accurately the leaf area of individual trees.MethodsAllometries of the measured leaf area of 194 trees in 12 stands were analysed in order to find variables affecting leaf area. Existing functions from the literature were validated. Finally, models were fitted to find the most appropriate method for estimating leaf area of mixed and monospecific stands of Norway spruce and European larch.ResultsAllometric relationships of leaf area to other measurable characteristics of trees vary in different stand types. Besides individual tree dimensions such as diameter and crown surface area, leaf area of Norway spruce is related to stand density, whereas the leaf area of European larch is dependent on the admixture of Norway spruce in the stand.ConclusionIn contrast to models for estimating individual tree leaf area of Norway spruce, models for leaf area of European larch have to consider mixture proportions in order to correctly interpret the growth efficiency of mixed stands.

中文翻译：

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挪威云杉（Picea abies L. Karst.）和欧洲落叶松（Larix decidua Mill.）的叶面积是否受混合比例和林分密度的影响？

如果它们位于不同的立式类型中，则具有其他相同维度的关键消息树具有不同的叶面积。欧洲落叶松的叶面积受混合比例的影响，挪威云杉的叶面积受林分密度的影响。尽可能准确。在比较单种林分和混合林分时，这一点更为重要。 目的研究的目的是找到可用于准确估计个体树木叶面积的参数组合和异速生长关系。方法测量叶面积的异速生长为了找出影响叶面积的变量，分析了 12 个林分中的 194 棵树。验证了文献中的现有功能。最后，拟合模型以找到估算挪威云杉和欧洲落叶松混合和单种林分叶面积的最合适方法。除了直径和树冠表面积等个体树木尺寸外，挪威云杉的叶面积与林分密度有关，而欧洲落叶松的叶面积取决于林分中挪威云杉的混合物。结论与模型对比为估算挪威云杉的个体树叶面积，欧洲落叶松叶面积模型必须考虑混合比例，才能正确解释混合林分的生长效率。