Above- and below-ground herbivory are key ecosystem processes that can be substantially altered by environmental changes. However, direct comparisons of the coupled variations of above- and below-ground herbivore communities along elevation gradients remain sparse. Here, we studied the variation in assemblages of two dominant groups of herbivores, namely, aboveground orthoptera and belowground nematodes, in grasslands along six elevation gradients in the Swiss Alps. By examining variations of community properties of herbivores and their food plants along montane clines, we sought to determine whether the structure and functional properties of these taxonomic groups change with elevation. We found that orthoptera decreased in both species richness and abundance with elevation. In contrast with aboveground herbivores, the taxonomic richness and the total abundance of nematode did not covary with elevation. We further found a stronger shift in above- than below-ground functional properties along elevation, where the mandibular strength of orthoptera matched a shift in leaf toughness. Nematodes showed a weaker pattern of declined sedentary behavior and increased mobility with elevation. In contrast to the direct exposal of aboveground organisms to the surface climate, conditions may be buffered belowground, which together with the influence of edaphic factors on the biodiversity of soil biota, may explain the differences between elevational patterns of above- and below-ground communities. Our study emphasizes the necessity to consider both the above- and below-ground compartments to understand the impact of current and future climatic variation on ecosystems, from a functional perspective of species interactions.

地上和地下的食草动物是关键的生态系统过程，可以通过环境变化而大大改变。然而，地上和地下食草动物群落沿海拔梯度的耦合变化的直接比较仍然很少。在这里，我们研究了瑞士阿尔卑斯山草地上两个主要的草食动物在地面上的直翅目和地下线虫的组合在六个海拔梯度上的变化。通过研究沿山地草食草动物及其食用植物的群落特性变化，我们试图确定这些分类群的结构和功能特性是否随海拔变化而变化。我们发现直翅目的物种丰富度和丰富度均随海拔升高而降低。与地上食草动物相比，线虫的分类学丰富度和总丰度与海拔无关。我们还发现，海拔高度的地下功能特性比地下功能特性的变化更强，直翅类的下颌骨强度与叶片韧性的变化相匹配。线虫显示出久坐行为减弱和活动性随海拔升高而减弱的模式。与将地上生物直接暴露于地表气候不同，地下条件可能得到缓冲，再加上土壤环境因素对土壤生物多样性的影响，这可能解释了地上和地下社区海拔格局之间的差异。 。我们的研究强调必须考虑地上和地下的隔间，以了解当前和未来的气候变化对生态系统的影响，