Soil Fungal Community Dynamics Associated with Seasonality Change and 4000Y of Ecosystem Development.

Numerous studies have looked at organisms succession at aboveground level, however there are no studies about microbial succession during ecosystem development describing fungal community change associated with long-term (>1000y) pedogenesis. Understanding the ecosystem development, the key process for the terrestrial biosphere functioning, and the study of the organisms responsible for shaping and driving these systems and their relationship with the vegetation and climate factors are overdue to be studied. It was hypothesized that fungal communities would change with pedogenesis, and these changes would correlate with vegetative community change and they should show change on composition and diversity as the season changes. Samples of sand dune soils from Northern Michigan composed of 9 different age classes ranging from 105 to 4010 years were sampled from the A-horizon (~0 to 10 cm depth). An additional base named time zero sample was collected along the beach simulating material that might be the source of the dune ridges. Targeting the Internal Transcribed Region (ITS) by using specific primers for this sequence, the samples were analyzed through pyrosequencing of the soil DNA. Bray-Curtis ordination showed a pattern of change in the fungal community during soil ecosystem development, with the greatest change during early succession compared to middle and late succession; with a 26% of the community change being described by the ecosystem development. The two dominant phyla were Ascomycota and Basidiomycota. Comparative sampling during winter and summer indicated a shift in the community, though these seasonal shifts appear to be smaller than the trends they shown to occur during ecosystem development. The observed patterns of change associated with long-term ecosystem development, point to the idea of possible linkages occurring between habitat change and fungal community succession.