We simulated an experimental summer storm in large-volume (~1200 m³, ~16m depth) enclosures in Lake Stechlin (https://www.lake-lab.de) by mixing deeper water masses from the meta- and hypolimnion into the mixed layer (epilimnion). The mixing included the disturbance of a deep chlorophyll maximum (DCM) which was present at the same time of the experiment in Lake Stechlin and situated in the metalimnion of each enclosure during filling. Size-fractionated Bacterial Protein Production (BPP) of particle associated (PA, >3.0 µm) and free-living bacteria (FL, 0.2-3.0 µm) (14C-Leu incorporation) as well as abundances of PA (microscopy of DAPI stained cells on 3.0 µm polycarbonate filters) and FL heterotrophic prokaryotes and picocyanobacteria (flow cytometry of SYBR green I stained cells) were monitored for 42 days after the experimental disturbance event. Mixing increased bacterial abundance and production about 3 weeks after mixing, which was associated to a mixing-induced stimulation of phytoplankton growth in the mixed enclosures compared to the controls. Simultaneously, decreased abundances of picocyanobacteria could be observed in mixed enclosures.
These data are part of the measurements conducted at the time series station Boknis Eck located in the southwestern Baltic Sea at 54°31.77'N, 10°02.36'E. The data include dissolved organic carbon (DOC), total dissolved nitrogen (TDN), dissolved organic nitrogen (DON), bacterial biomes production and bacterial cell counts. Samples were taken once a month at 6 standard depths (1, 5, 10, 15, 20 and 25 m). The data was acquired onboard FK Littorina using a rosette sampler. DOC/TDN were measured using a TOC analyzer, bacterial biomass production data was acquired by leucine incorporation (70 min incubation and counted using a liquid scintillation counter), and bacterial cell abundance was determined using flow cytometry.