Temperate forest canopies support a high diversity of insects, but in comparison to the tropics, little is known about insect spatial distribution, particularly in terms of vertical stratification. We used an aerial lift platform to sample a temperate floodplain forest canopy during two seasons. We aimed to describe patterns of aphid density and diversity in terms of vertical canopy stratification within a 0.2 ha forest plot. Vertical gradient affected both the density and diversity of aphids. There was no general pattern in aphid distribution that applied to the eight tree species included in our survey. The aphid taxocoenosis was stratified differently on particular tree species and changed during the season. Species composition was better explained by aboveground absolute position (in m), while aphid density was better explained by relative height in the tree (position in the crown). Considering that these factors were significant but that the same statistical models excluding any influence of relative or absolute position provided more robust explanations, we concluded that aphid spatial distribution in temperate forests is difficult to simplify. This likely depends on environmental factors, such as wind direction and strength, that affect aphid flight and landing.

中文翻译：

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温带森林树冠中蚜虫的空间分布：在哪里可以找到它们？

温带森林冠层支持高度多样性的昆虫，但与热带相比，对昆虫空间分布知之甚少，特别是在垂直分层方面。我们使用高空升降平台在两个季节对温带漫滩森林树冠进行采样。我们旨在根据 0.2 公顷森林地块内的垂直冠层分层来描述蚜虫密度和多样性的模式。垂直梯度影响蚜虫的密度和多样性。蚜虫分布没有适用于我们调查中的八种树种的一般模式。蚜虫分类群落在特定树种上的分层不同，并在季节期间发生变化。地上绝对位置（以米为单位）更好地解释了物种组成，而蚜虫密度可以通过树中的相对高度（在树冠中的位置）来更好地解释。考虑到这些因素很重要，但排除任何相对或绝对位置影响的相同统计模型提供了更可靠的解释，我们得出结论，温带森林中的蚜虫空间分布难以简化。这可能取决于影响蚜虫飞行和着陆的环境因素，例如风向和强度。