Soil invertebrate abundance, diversity, and community composition across steep high elevation snowmelt gradients in the European Alps

We studied abundance, diversity, and composition of soil invertebrates along snowmelt gradients to generally understand how soil animal communities are responding to life conditions across snowbeds along a west–east transect of the European Alps and to create a reference inventory for future investigations of climate change effects on snowbed habitats. We extracted microarthropods (collembolans, oribatid mites) and macroinvertebrates (spiders, beetles, insect larvae) from soil cores taken from three sections along the snowmelt gradient: high (early snowmelt), middle, and low (late snowmelt) sections. Linear models showed no correlations between either soil conditions or time of snowmelt and densities of soil animals. A small, though statistically significant, variation in the generally high soil organic matter and sand contents and high porosity of snowbed soils seems to have no effect on soil invertebrates. Species found along the snowmelt gradient were in similar shares generalist and specialist species. Microarthropod community composition in general was driven by soil porosity and soil organic matter content; for macroinvertebrate community composition we found no specific driver. We conclude that invertebrate species assemblages in snowbeds are rather similar in the European Alps.

本研究沿融雪梯度对土壤无脊椎动物的丰度、多样性及群落组成展开调查，旨在整体阐明欧洲阿尔卑斯山脉东西样带内雪床生境的土壤动物群落如何响应生境条件，并为未来开展气候变化对雪床生境影响的相关研究提供参考名录。我们从沿融雪梯度划分的三个区段——融雪早的高海拔区段、中海拔区段及融雪晚的低海拔区段——获取的土芯中，分离得到微型节肢动物（弹尾虫、甲螨）与大型无脊椎动物（蜘蛛、甲虫、昆虫幼虫）。线性模型分析结果显示，土壤条件与融雪时间均与土壤动物密度无显著相关性。尽管雪床土壤的有机质含量、砂粒占比普遍较高且孔隙度较大，仅存在微小但具统计学显著性的变异，但该变异似乎并未对土壤无脊椎动物产生影响。沿融雪梯度分布的物种中，广食性物种与专食性物种的占比相近。总体而言，微型节肢动物群落组成受土壤孔隙度与有机质含量调控；而大型无脊椎动物群落组成未发现明确的驱动因子。我们得出结论：欧洲阿尔卑斯山脉雪床生境中的无脊椎动物物种组合具有较高的相似性。