Influence of different soil uses in the Pampa biome, southern Brazil, on fungal communities

Abstract

Anthropogenic activities in any natural ecosystem cause changes that affect the physical and biological environment, causing degradation. Likewise, these activities can cause significant changes in the chemical and physical factors of the soil, also impacting the microbiological community. The study aimed to evaluate the influence of soil biochemical and physicochemical characteristics on the development of fungal communities in three different soils of the Pampa biome. The soil types selected were: native forest, Eucalyptus plantation and pasture area, in two distinct periods: hot and cold. Microbiological, physicochemical and biochemical analyses of the soils were carried out. The following genera and species of fungi were identified:Aspergillus sp., Aspergillus niger, Fusarium sp., Geotrichum sp., Isaria sp., Penicillium sp., Scedosporium sp., Trichoderma sp., Verticilliumsp. The results showed that the fungal community is being affected by soil composition characteristics, regardless of the sampled areas. Aspergillus sp. is associated with higher amounts of manganese, boron and the Ca+Mg/K ratio in the soil, while A. niger and Trichodermasp. have a negative relationship with these variables. Aspergillus sp. showed a high ability to tolerate Mn. The most diverse area was pasture in the warm period, and the least diverse was Eucalyptus plantation in the cold period. The analyzed taxa had a reduction in the cold period compared to the warm one, except for Aspergillussp. in the Eucalyptus area, which presented a greater amount in the cold period compared to the hot period. It can be seen that the use of soil in the Pampa biome for planting monocultures or for generating pastures interferes with its characteristics and distinctly affects the fungal community.