Impact of plant invasion (Solidago gigantea L.) on soil mesofauna in a riparian wet meadows

- Soil mesofauna response to S. gigantea invasion in wet meadows was examined.
- Soil properties of wet meadows changed significantly following invasion.
- Altered soil properties under invasive plant affected composition of the Collembola community.
- Abundance of soil mesofauna and feeding guilds was not changed on invaded sites.

Invasive plants are known to have significant impacts on habitat structure and abiotic properties of the soil, and can noticeably modify soil animal community composition, diversity and function. We studied the effects of environmental change induced by an intercontinental, exotic invasive plant, Solidago gigantea L., on the resident Collembola and Protura communities at the species level, abundance of the soil mesofaunal communities at a coarse taxonomic level (Collembola, Protura, Oribatida, Gamasida, Actinedida) and abundance of the major trophic guilds (detritivores and predators). This research was conducted in an extended complex of riparian Molinia meadows in the upper Vistula drainage basin, SE Poland. Soil properties and soil mesofaunal communities were compared between Molinia meadow patches in well-established S. gigantea-invaded sites (about 20 years old) and uninvaded patches of Molinia meadows. Our results showed significant invader effects on soil properties such as pH. Collembola communitiy composition, in contrast to Protura communities, were significantly different between invaded vs. uninvaded meadows. Soil mesofaunal communities as measured by abundance of the major taxa were not altered, and relative abundance of detritivores and predators remained the same. The study shows that observed changes in soil properties induced by invasive plants can have a moderate effect on soil mesofaunal diversity and structure, primarily with regard to Collembola community composition, and a weak effect on modifications of the trophic structure.