A species-level multi-trophic metaweb for Switzerland.

Understanding how species interact within ecological networks is essential for predicting the consequences of environmental change, from trophic cascades to broader changes in species distributions and ecosystem functioning across large spatial scales. To facilitate such explorations, we constructed trophiCH: a country-level trophic meta-food web (henceforth "metaweb") that includes vertebrates, invertebrates, and vascular plants within Switzerland, based on literature published between 1862 and 2023. Our comprehensive dataset catalogues 1,112,073 trophic interactions involving 23,151 species and 125 feeding guilds (e.

Species loss in key habitats accelerates regional food web disruption.

Understanding the robustness of ecological networks against sustained species losses is paramount to devising effective biodiversity conservation strategies. To explore the impacts of species losses on network robustness (the capacity of food webs to withstand primary extinctions), we used a trophic metaweb of 7808 vertebrates, invertebrates and plants and 281,023 interactions across Switzerland. We inferred twelve regional multi-habitat food webs and simulated non-random species extinction scenarios on these webs, focusing on broad habitat types and regional species abundances.

Catchment-based sampling of river eDNA integrates terrestrial and aquatic biodiversity of alpine landscapes.

Monitoring of terrestrial and aquatic species assemblages at large spatial scales based on environmental DNA (eDNA) has the potential to enable evidence-based environmental policymaking. The spatial coverage of eDNA-based studies varies substantially, and the ability of eDNA metabarcoding to capture regional biodiversity remains to be assessed; thus, questions about best practices in the sampling design of entire landscapes remain open. We tested the extent to which eDNA sampling can capture the diversity of a region with highly heterogeneous habitat patches across a wide elevation gradient for five days through multiple hydrological catchments of the Swiss Alps.

Blue and green food webs respond differently to elevation and land use.

While aquatic (blue) and terrestrial (green) food webs are parts of the same landscape, it remains unclear whether they respond similarly to shared environmental gradients. We use empirical community data from hundreds of sites across Switzerland and a synthesis of interaction information in the form of a metaweb to show that inferred blue and green food webs have different structural and ecological properties along elevation and among various land-use types. Specifically, in green food webs, their modular structure increases with elevation and the overlap of consumers' diet niche decreases, while the opposite pattern is observed in blue food webs.