Gossner Martin M, Lade Peggy, Rohland Anja, Sichardt Nora, Kahl Tiemo, Bauhus Jürgen, Weisser Wolfgang W, Petermann Jana S
Terrestrial Ecology Research Group, Department of Ecology and Ecosystem Management, Center for Food and Life Sciences Weihenstephan, Technische Universität München, Hans-Carl-von-Carlowitz-Platz 2, 85354, Freising-Weihenstephan, Germany.
Institute of Ecology, Friedrich-Schiller-University, 07745, Jena, Germany.
J Anim Ecol. 2016 Jan;85(1):213-26. doi: 10.1111/1365-2656.12437. Epub 2015 Oct 5.
Arthropod communities in water-filled tree holes may be sensitive to impacts of forest management, for example via changes in environmental conditions such as resource input. We hypothesized that increasing forest management intensity (ForMI) negatively affects arthropod abundance and richness and shifts community composition and trophic structure of tree hole communities. We predicted that this shift is caused by reduced habitat and resource availability at the forest stand scale as well as reduced tree hole size, detritus amount and changed water chemistry at the tree holes scale. We mapped 910 water-filled tree holes in two regions in Germany and studied 199 tree hole inhabiting arthropod communities. We found that increasing ForMI indeed significantly reduced arthropod abundance and richness in water-filled tree holes. The most important indirect effects of management intensity on tree hole community structure were the reduced amounts of detritus for the tree hole inhabiting organisms and changed water chemistry at the tree hole scale, both of which seem to act as a habitat filter. Although habitat availability at the forest stand scale decreased with increasing management intensity, this unexpectedly increased local arthropod abundance in individual tree holes. However, regional species richness in tree holes significantly decreased with increasing management intensity, most likely due to decreased habitat diversity. We did not find that the management-driven increase in plant diversity at the forest stand scale affected communities of individual tree holes, for example via resource availability for adults. Our results suggest that management of temperate forests has to target a number of factors at different scales to conserve diverse arthropod communities in water-filled tree holes.
积水树洞中的节肢动物群落可能对森林管理的影响较为敏感，例如可能会受到诸如资源输入等环境条件变化的影响。我们假设，森林管理强度增加（ForMI）会对节肢动物的丰度和丰富度产生负面影响，并改变树洞群落的组成和营养结构。我们预测，这种变化是由林分尺度上栖息地和资源可用性的降低以及树洞尺度上树洞大小减小、碎屑量减少和水化学性质改变所导致的。我们绘制了德国两个地区910个积水树洞的地图，并研究了199个栖息着节肢动物的树洞群落。我们发现，森林管理强度增加确实显著降低了积水树洞中节肢动物的丰度和丰富度。管理强度对树洞群落结构最重要的间接影响是，栖息在树洞中生物的碎屑量减少以及树洞尺度上的水化学性质改变，这两者似乎都起到了栖息地过滤的作用。尽管随着管理强度的增加，林分尺度上的栖息地可用性降低，但这却意外地增加了单个树洞中节肢动物的局部丰度。然而，随着管理强度的增加，树洞中区域物种丰富度显著下降，这很可能是由于栖息地多样性降低所致。我们没有发现林分尺度上管理驱动的植物多样性增加会影响单个树洞的群落，例如通过影响成虫的资源可用性。我们的研究结果表明，温带森林的管理必须针对不同尺度的多个因素，以保护积水树洞中多样的节肢动物群落。
