Ant communities andSolidagoplant invasion: Environmental properties and food sources

Abstract

AbstractThe invasion ofSolidagois one of the main threats to the biodiversity of natural meadows, leading to changes in animal and plant communities, as well as soil features. We compared effects of soil microclimatic conditions (temperature and moisture) and the availability of potential protein sources (dry mass of epigean invertebrates) on ants between meadows invaded bySolidago altissimaandS. canadensisand those uninvaded. Our results showed that the ant communities were different between the uninvaded and invaded meadows, with reduction of ant abundance and species richness in the latter.Myrmicaspp. were abundant in the uninvaded meadows, whereasLasius nigerwas the dominant species in the invaded ones. We found that the lower moisture negatively influenced the abundance ofMyrmicaspecies in theSolidago‐invaded meadows. Moreover, the epigean invertebrate dry mass, as an estimation of the availability of protein sources, varied between the two types of meadows, with a higher abundance in the uninvaded ones. The abundance ofMyrmicaants with narrower ecological requirements showed a positive correlation with the invertebrate biomass in the invaded meadows. In contrast, the abundance ofL. nigerwith broad ecological requirements was negatively correlated with the invertebrate biomass in the invaded meadows, possibly as a strategy to reduce interspecific competition. Our study showed that the invasion ofSolidagoplants caused changes in the abundance and species composition of ant communities through modification in microhabitat conditions, that is, decreasing soil moisture, reducing biomass and changing distribution of prey invertebrates.