Bacterial diversity and processes to short-term oxygen depletion: manipulation experiment in the Venice lagoon

In this study hypoxic conditions were induced in the laboratory using sediment patches with different primary producers (i.e. microphytobenthos, macroalgae and seagrasses). Normoxic conditions were then restored. Bacterial diversity and benthic processes were investigated before, during, and after the onset of hypoxia, as well as after reoxygenation. Prokaryotes (16S rDNA massive sequencing), functional proxies (extracellular enzymatic activities), and net fluxes of O2, CO2, N2, NO3-, NH4+ were measured at the water-sediment interface. The experiment outcomes highlighted variable responses of microbial diversity and putative functions, evidencing a link between community shifts and differential vegetated sediments during oxygen reduction and recovery.