Invasion‐mediated mutualism disruption is evident across heterogeneous environmental conditions and varying invasion intensities

作者：Morgan D. Roche, Ian S. Pearse, Helen R. Sofaer, Stephanie N. Kivlin, Greg Spyreas, David N. Zaya, Susan Kalisz · 发表于：Ecography · 年份：2023 · DOI：10.1111/ecog.06434 · 被引用次数：11 · 研究领域：Ecology and Vegetation Dynamics Studies、Plant and animal studies、Plant Parasitism and Resistance

The impact of a biological invasion on native communities is expected to be uneven across invaded landscapes due to differences in local abiotic conditions, invader abundance, and traits and composition of the native community. One way to improve predictive ability about the impact of an invasive species given variable conditions is to exploit known mechanisms driving invasive species' success. Invasive plants frequently exhibit allelopathic traits, which can be directly toxic to plants or indirectly impact them via disruption of root symbionts, including mycorrhizal fungi. The indirect mechanism – mutualism disruption – is predicted to impact plants that rely on mycorrhizas but not affect non‐mycorrhizal plant species. To assess whether invader‐driven mutualism disruption explains observed changes in native plant communities, we analyzed long‐term (1998–2018) plant cover data from forest plots across the state of Illinois. We evaluated native plant communities experiencing a range of abundance of invasive allelopathic garlic mustard Alliaria petiolata and varying environmental conditions. Consistent with the mutualism disruption hypothesis, we showed that as garlic mustard abundance increased over time in 0.25 m 2 sampling quadrats, the abundance of mycorrhizal plant species decreased, but non‐mycorrhizal plant species did not. Over space and time, garlic mustard abundance predicted plant abundances and diversity at the quadrat level, but this relationship was not present at...