Popis: |
Organism succession during ecosystem development has been researched for aboveground plant communities, however, the associated patterns of change in below-ground microbial communities are less described. In 2008, a study was initiated along a developmental sand-dune soil chronosequence bordering northern Lake Michigan near Wilderness Park (WP). It was hypothesized that soil bacterial communities would follow a pattern of change that is associated with soil, plant, and ecosystem development. This study included 5 replicate sites along 9 soils (n = 45) ranging in age from ∼105 to 4010 years since deposition. Soil bacterial community composition and diversity were studied using bacterial tag-encoded FLX amplicon pyrosequencing of the 16S rRNA gene. Bray–Curtis ordination indicated that bacterial community assembly changed along the developmental soil and plant gradient. The changes were not affected by seasonal differences, despite likely differences in plant root C (e.g. exudates), temperature, and water availability in soil. Soil base cations (Ca, Mg) and pH declined, showing log-linear correlations with soil age (r ∼ 0.83, 0.84 and 0.81; P 450 y) did not change. Turnover of plant taxa was also more rapid early during ecosystem development and correlated with bacterial community structural change (P |