Incorporation of mineral nitrogen into the soil food web as affected by plant community composition

作者：Tanja Strecker, Annette Jesch, Dörte Bachmann, Melissa Jüds, Kevin Karbstein, Janneke Ravenek, Christiane Roscher, Alexandra Weigelt, Nico Eisenhauer, Stefan Scheu · 发表于：Ecology and Evolution · 年份：2021 · DOI：10.1002/ece3.7325 · 被引用次数：12 · 研究领域：Soil Carbon and Nitrogen Dynamics、Ecology and Vegetation Dynamics Studies、Study of Mite Species

Abstract Although nitrogen (N) deposition is increasing globally, N availability still limits many organisms, such as microorganisms and mesofauna. However, little is known to which extent soil organisms rely on mineral‐derived N and whether plant community composition modifies its incorporation into soil food webs. More diverse plant communities more effectively compete with microorganisms for mineral N likely reducing the incorporation of mineral‐derived N into soil food webs. We set up a field experiment in experimental grasslands with different levels of plant species and functional group richness. We labeled soil with 15 NH 4 15 NO 3 and analyzed the incorporation of mineral‐derived 15 N into soil microorganisms and mesofauna over 3 months. Mineral‐derived N incorporation decreased over time in all investigated organisms. Plant species richness and presence of legumes reduced the uptake of mineral‐derived N into microorganisms. In parallel, the incorporation of mineral‐derived 15 N into mesofauna species declined with time and decreased with increasing plant species richness in the secondary decomposer springtail Ceratophysella sp. Effects of both plant species richness and functional group richness on other mesofauna species varied with time. The presence of grasses increased the 15 N incorporation into Ceratophysella sp., but decreased it in the primary decomposer oribatid mite Tectocepheus velatus sarekensis . The results highlight that mineral N is quickly channeled ...