Soil fungal community change associated with ecosystem development

Background/Question/Methods: Despite soils and microorganisms having been long considered key to ecosystem functions, and researchers have looked at organismal succession at the aboveground level, the composition of belowground fungal communities have not been adequately studied in the context of the natural process of ecosystem development. It is still unknown how fungal community change is related to long-term (>1000y) ecosystem development driven by vegetation and or mineral-organic matter change. It was hypothesized that fungal community richness would change with ecosystem development (vegetative succession and seasonality change). The objective of this study was to establish whether plant succession could be used as factor predicting fungal community composition in soil chronosequences under study. Samples of sand dune soils from Northern Michigan composed of 9 classes ranging from 105 to 4010 years were sampled from the A-horizon (~0 to 10 cm depth). Analyses of the samples through pyrosequencing of the soil DNA targeting the Internal Transcribed Region (ITS) region were made.

Results/Conclusions: Bray-Curtis ordination indicated two primary patterns related to Axis 1 and Axis 2. These axes showed an equivalent relationship (27%) between the fungal community structure and ecosystem development. This 27% of the community change could be explained by ecosystem development, with the greatest change happening during early succession compared to middle and late succession. The two dominant phyla were Ascomycota (47.5%) and Basidiomycota (14.7%). According to what was hypothesized it was expected that fungal communities would change with pedogenesis, and that this change could be correlated with plant community change.