Speaker
Description
Soil food webs, driven by complex interactions among plants, microbes and invertebrates, are crucial for carbon and nutrient cycling in forest ecosystems. Over the last decade it has become evident that forests dominated by arbuscular mycorrhizal fungi (AMF) or ectomycorrhizal fungi (EMF) differ in their litter chemistry and microbial community composition, leading to different carbon and nutrient cycling. Still, the role of soil invertebrates in soil food webs of AMF- and EMF-dominated forests remains undescribed. Here, we tested whether trophic positions (TP) and basal resources of nine soil invertebrate groups (Araneae, Chilopoda, Collembola, Diplopoda, Diptera, Isopoda, Lumbricina, Mesostigmata, and Oribatida) are different in AMF- and EMF-dominated deciduous forests. We addressed this question using compound-specific stable isotope analysis of carbon and nitrogen in amino acids (CSIA-AA) – a novel method that allows precise estimation of the TP and basal resource use (bacteria, fungi, plant) of consumers in field conditions. Plant- and microbial-derived resources of soil invertebrates generally varied little between AMF and EMF-dominated forests. We only found a slight tendency of soil invertebrates in AMF-dominated forests relying more on fungal- and more on bacteria-derived resources in EMF-dominated systems. Most of the variation in resource use was explained by the taxonomic identity of invertebrates, independently of the forest type. Mesofauna, particularly Collembola and Oribatida, were key consumers of fungi, while macrofauna (except earthworms) relied more on plant resources, suggesting that different size compartments of soil food webs predominantly use different basal resources. Earthworms and Myriapoda had the highest proportions of bacteria-derived essential amino acids. TPs of taxa remained largely consistent across mycorrhizal types suggesting similar vertical organisation of soil food webs across the studied forests. Overall, our study shows that TPs and basal resource use of soil fauna vary little across temperate deciduous forests, being mainly explained by the faunal taxonomic identity.
| Status Group | Doctoral Researcher |
|---|---|
| Poster Presentation Option | No, I prefer to present only as a talk. |
