RT Journal Article
SR Electronic
T1 Aboveground impacts of a belowground invader: how invasive earthworms alter aboveground arthropod communities in a northern North American forest
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.12.02.470883
DO 10.1101/2021.12.02.470883
A1 Malte Jochum
A1 Lise Thouvenot
A1 Olga Ferlian
A1 Romy Zeiss
A1 Bernhard Klarner
A1 Ulrich Pruschitzki
A1 Edward A. Johnson
A1 Nico Eisenhauer
YR 2021
UL http://biorxiv.org/content/early/2021/12/03/2021.12.02.470883.abstract
AB Declining arthropod communities have recently gained a lot of attention with climate and land-use change among the most-frequently discussed drivers. Here, we focus on a seemingly underrepresented driver of arthropod-community decline: biological invasions. For ∼12,000 years, earthworms have been absent from wide parts of northern North America, but they have been re-introduced with dramatic consequences. Most studies investigating earthworm-invasion impacts focus on the belowground world, resulting in limited knowledge on aboveground-community changes. We present observational data on earthworm, plant, and aboveground-arthropod communities in 60 plots, distributed across areas with increasing invasion status (low, medium, high) in a Canadian forest. We analyzed how earthworm-invasion status and biomass impact aboveground arthropod community abundance, biomass, and species richness, and how earthworm impacts cascade across trophic levels. We sampled ∼13,000 arthropods, dominated by Hemiptera, Diptera, Araneae, Thysanoptera, and Hymenoptera. Total arthropod abundance, biomass, and species richness declined significantly from areas of low to those with high invasion status with reductions of 61, 27, and 18%, respectively. Structural Equation Models unraveled that earthworms directly and indirectly impact arthropods across trophic levels. We show that earthworm invasion can alter aboveground multitrophic arthropod communities and suggest that belowground invasions can be important drivers of aboveground-arthropod decline.Competing Interest StatementThe authors have declared no competing interest.