Arbuscular mycorrhizal fungal community assembly in agroforestry systems from the Southern Brazil

Abstract

Soil ecosystem disturbances promoted by the biological invasion can promote soil food web degradation by disrupting arbuscular mycorrhizal fungi (AMF) community structure. We aimed to compare the benefit of native tree plantings (e.g., Araucaria angustifolia, Ilex paraguariensis, and Mimosa scabrella) in a 5-year agroforestry system to overcome the soil disturbance due to invasion by Pine trees on AMF community composition in the Southern Brazil to natural restoration (unassisted forest ecosystem). We used morphological AMF identification and the natural forest as reference ecosystem. AMF diversity and dominance in the native tree species and unassisted forest ecosystem were similar, but these environments showed higher values when compared to the natural ecosystem. The PCA analysis showed soil pH, microbial biomass carbon, AMF richness, and the presence of Claroideoglomus etunicatum, Dentiscutata cerradensis, Gigaspora species, and Glomus sp. as the main factors contributing to the variance of the samples. In general, the most abundant AMF species presented in all studied ecosystems was Funneliformis mosseae. Differences in AMF community structure and soil properties were associated with (1) ecosystem disturbance, (2) changes in soil properties such as soil pH, (3) rootability by fine root production, and (4) rhizodeposition by soil microbial carbon as observed into the PCA analysis. These results contribute to a deeper view of the AMF communities in agroforestry systems and open new perspective for the management of degraded lands by biological invasion involving AMF species and native tree species in the Southern Brazil.