Skip to main content
Dryad

Data from: Cascading effects of earthworm invasion in tundra increase graminoid density and rodent grazing intensities

Jonsson, Hanna1; Olofsson, Johan1; Blume-Werry, Gesche1; Klaminder, Jonatan1

Research facility: Abisko Scientific Research Station
Published Nov 08, 2023 on Dryad. https://doi.org/10.5061/dryad.zpc866tbm

Data files

Nov 08, 2023 version files 1.74 MB

Click names to download individual files

Abstract

Earthworms are being introduced to numerous ecosystems through human activities. Some non-native earthworm species have the potential to ‘geoengineer’ soils and increase plant nitrogen (N) uptake, but if the increased plant N concentrations can cause increased rodent grazing is not well known. In this study, we present findings from a common garden experiment with two tundra communities, meadow (forb dominated) and heath (shrub dominated), half of them subjected to four years of earthworm presence (Lumbricus spp. and Aporrectodea spp.). Within four summers, our earthworm treatment changed plant community composition by increasing graminoid density by on average 94 % in the heath vegetation and by 49 % in the meadow. Rodent winter grazing were more intense on plants growing in soils with earthworms, an effect that coincided with higher nitrogen concentrations in plants indicating a higher palatability. Moreover, although the earthworms decreased soil moisture, our proxy for plant community photosynthesis (greenness) was not negatively affected. We conclude that earthworm-induced changes in plant composition and trophic interactions may radically alter the functioning of tundra ecosystems.