Data for: Elevational changes in insect herbivory on woody plants in six mountain ranges of temperate Eurasia: Sources of variation

Current theory predicts that the intensity of biotic interactions, and
particularly herbivory, decreases with increasing latitude and elevation.
However, recent studies have revealed substantial variation in both the
latitudinal and elevational patterns of herbivory. This variation is often
attributed to differences in study design and type of data collected by
different researchers. Here, we used a standardised sampling protocol
along elevational gradients in six mountain ranges, located at different
latitudes within temperate Eurasia, to uncover the sources of variation in
elevational patterns in insect herbivory on woody plant leaves. We
discovered the considerable variation in elevational patterns among
different mountain ranges; nevertheless, herbivory generally decreased
with increasing elevation at both the community-wide and individual plant
species levels. This decrease was mostly due to openly living defoliators,
whereas no significant association was detected between herbivory and
elevation among insects living within plant tissues (i.e. miners and
gallers). The elevational decrease in herbivory was significant for
deciduous plants but not for evergreen plants, and for low-stature plants
but not for tall plants. The community-wide herbivory increased with
increases in both specific leaf area and leaf size. The strength of the
negative correlation between herbivory and elevation increased from lower
to higher latitudes. We conclude that elevational gradients in herbivory
demonstrate considerable variation, and that this variation is mostly
associated with herbivore feeding habit, some plant traits and latitude of
the mountain range.

现有理论预测，生物相互作用的强度，尤其是植食作用的强度，会随纬度与海拔的升高而降低。然而，近期研究却揭示出植食作用的纬度格局与海拔格局均存在显著变异。该变异常被归因于不同研究者的研究设计与数据采集类型存在差异。本研究针对温带欧亚大陆不同纬度带的6座山脉的海拔梯度采用标准化采样方案，旨在揭示木本植物叶片昆虫植食作用海拔格局的变异来源。研究发现，不同山脉的植食作用海拔格局存在显著差异；但总体而言，无论是群落尺度还是单个植物物种尺度，植食作用均随海拔升高而降低。该降低趋势主要源于裸露生活的食叶植食者，而生活在植物组织内的昆虫（即潜叶昆虫与造瘿昆虫）的植食作用与海拔未呈现显著关联。植食作用的海拔降低趋势在落叶植物中显著存在，而常绿植物则无此趋势；同时该趋势仅在低矮植物中显著，高大植物则不然。群落尺度的植食作用随比叶面积与叶片尺寸的增大而升高。植食作用与海拔之间的负相关强度随纬度升高而增强。综上，植食作用的海拔梯度格局存在显著变异，且该变异主要与植食者的取食习性、部分植物性状以及山脉所处纬度相关。