Schellenberger Costa David, Classen Alice, Ferger Stefan, Helbig-Bonitz Maria, Peters Marcell, Böhning-Gaese Katrin, Steffan-Dewenter Ingolf, Kleyer Michael
Department of Biology and Environmental Sciences, University of Oldenburg, Oldenburg, Germany.
Department of Animal Ecology and Tropical Biology, University of Würzburg, Würzburg, Germany.
PLoS One. 2017 Mar 20;12(3):e0174157. doi: 10.1371/journal.pone.0174157. eCollection 2017.
The effect-response framework states that plant functional traits link the abiotic environment to ecosystem functioning. One ecosystem property is the body size of the animals living in the system, which is assumed to depend on temperature or resource availability, among others. For primary consumers, resource availability may directly be related to plant traits, while for secondary consumers the relationship is indirect. We used plant traits to describe resource availability along an elevational gradient on Mount Kilimanjaro, Tanzania. Using structural equation models, we determined the response of plant traits to changes in precipitation, temperature and disturbance with and assessed whether abiotic conditions or community-weighted means of plant traits are stronger predictors of the mean size of bees, moths, frugivorous birds, and insectivorous birds. Traits indicating tissue density and nutrient content strongly responded to variations in precipitation, temperature and disturbance. They had direct effects on pollination and fruit traits. However, the average body sizes of the animal groups considered could only be explained by temperature and habitat structure, not by plant traits. Our results demonstrate a strong link between traits and the abiotic environment, but suggest that temperature is the most relevant predictor of mean animal body size. Community-weighted means of plant traits and body sizes appear unsuitable to capture the complexity of plant-animal interactions.
效应-响应框架表明，植物功能性状将非生物环境与生态系统功能联系起来。生态系统的一个属性是生活在该系统中的动物的体型大小，一般认为它取决于温度或资源可用性等因素。对于初级消费者来说，资源可用性可能直接与植物性状相关，而对于次级消费者来说，这种关系是间接的。我们利用植物性状来描述坦桑尼亚乞力马扎罗山沿海拔梯度的资源可用性。通过结构方程模型，我们确定了植物性状对降水、温度和干扰变化的响应，并评估了非生物条件或植物性状的群落加权平均值是否是蜜蜂、飞蛾、食果鸟类和食虫鸟类平均体型大小的更强预测指标。表明组织密度和营养成分的性状对降水、温度和干扰的变化有强烈响应。它们对授粉和果实性状有直接影响。然而，所考虑的动物群体的平均体型大小只能由温度和栖息地结构来解释，而不能由植物性状来解释。我们的结果表明性状与非生物环境之间存在紧密联系，但表明温度是平均动物体型大小最相关的预测指标。植物性状和体型大小的群落加权平均值似乎无法捕捉植物-动物相互作用的复杂性。
