Microbial community shifts trigger loss of orthophosphate in wetland soils subjected to experimental warming.

Aims: Microbial-driven biogeochemical cycles of phosphorus (P) in wetlands subjected to global climate warming result in a downstream eutrophication risk. However, how warming influences P associated with microbial shifts in wetland soils is largely unknown.Methods: A custom-built, novel microcosm that simulated climate warming was established under ambient temperature and elevated warming conditions (+ 3 °C). ³¹P nuclear magnetic resonance (³¹P-NMR) technology was used to characterize different P forms and high-throughput sequencing of 16S rRNA gene was used to identify microbial community and functional potentials in wetland soils varied with nutrition status.Results: Soil P forms were dominated by orthophosphate. The dynamic changes of different P forms in response to warming were mainly observed in high nutrition wetlands. The relative abundance of orthophosphate and polyphosphate (inorganic) significantly (<italic>p</italic> < 0.05) decreased, which was accompanied with increased phosphonate (organic) under warming. Consistently, soil microbial community shifts were also found in high nutrition wetlands, especially in fall with significantly (<italic>p</italic> < 0.05) increased relative abundance of <italic>Alphaproteobacteria</italic> and <italic>Betaproteobacteria</italic> and decreased <italic>Clostridia</italic> under warming<italic>.</italic> The microbial functions related to catabolism, the transport, degradation and release of P were enriched under warming. Changed microbial community may have altered the overall functional potentials which were responsible for P dynamics.Conclusions: Soil microbial community shifts in response to experimental warming were season-based. Microbial changes and P shifts from high nutrition wetlands were more sensitive to warming. The changed microbial community under warming conditions may trigger the loss of orthophosphate through the altered functional potentials. These findings aid to better understand microbial-driven biogeochemical cycles of P in wetland soils under future climate changes. [ABSTRACT FROM AUTHOR]