Invasion of Celtis tala forests by Ligustrum lucidum in Argentina: impact on soil properties and the arbuscular mycorrhizal fungi community

The arrival of invasive plants can cause drastic changes to ecosystems, such as the displacement of native plant communities and the disruption of ecological functions. Ligustrum lucidum W.T. Aiton is an invasive tree species that has been registered in numerous regions worldwide. We analysed the effect of the expansion of L. lucidum on the edaphic properties and mycorrhizal fungal communities in forests of Celtis tala Gillies ex Planch. located in central–western Argentina. Sampling sites were established along a gradient of invasion, in which we measured the forest structure and soil physicochemical factors and identified the fungal species using morphological techniques. The analysis of the variance revealed severe changes in the tree structure and a decrease in the concentrations of organic matter and nitrogen in the invaded sites. Thirty-two Glomeromycota species were identified, belonging to six families. The abundance of Dentiscutata cerradensis decreased with the invasion, whereas Funneliformis mosseae and Septoglomus constrictum increased. The alpha diversity of the arbuscular mycorrhizal communities showed no differences between sites. The beta diversity decreased at invaded sites, indicating a tendency towards convergence and reduced variability in these communities in the presence of the exotic species.