Physiological Profiling of Soil Microbial Communities in a Florida Scrub-Oak Ecosystem: Spatial Distribution and Nutrient Limitations

摘要: Rapid physiological profiling of heterotrophic microbial communities enables intensive analysis the factors affecting activity in aerobic habitats, such as soil. Previous methods for performing were severely limited due to enrichment bias and inflexibility incubation conditions. We tested a new approach based on microtiter plate oxygen sensor system (Becton Dickinson Oxygen Biosensor System (BDOBS)), which allows testing lower substrate addition (i.e., potential) manipulation physiochemical assay conditions, pH nutrients. Soil associated with scrub-oak forest ecosystem Merritt Island Wildlife Refuge central Florida, USA, studied order evaluate nutrient poor soil provide baseline data site subsequent evaluation effects elevated CO2 function. The spatial variation amongst different habitats (litter, bulk soil, rhizosphere) was examined function adaptation local resources water soluble extracts roots leaf litter) degree N P limitation. All primarily N-limited, secondary limitation, greater rhizosphere litter community showed overall consumption when exposed relative or suggesting acclimation toward use mixed substrates extract. Root readily used by from all no habitat specific observed. A priming effect detected habitats; glucose caused significant increase organic carbon. Response added only observed addition, that C may be lost groundwater these porous soils because limitation prevents immobilization.