Action #8: Extreme events affecting phytoplankton

AQUACOSM collaboration I

Objectives: The plankton ecosystem reacts rapidly to the shifts in various environmental pressures. These responses may be tracked using high-resolution observations with state-of-art sensors, but still many of the interactions in the planktonic realm may remain hidden. For example, rate measurements and food web interactions are hard to measure without enclosing the plankton communities for the period when measurements are done. As well, understanding the responses of planktonic systems to some specific perturbations may require that part of the ecosystem is isolated and studied experimentally. This topic will study how the Baltic Sea phytoplankton communities are affected by extreme climatic forcing, in collaboration with experimental work of AQUACOSM-plus and supported by long-term observational data.

Action Lead and other Partners (with contact persons): SYKE (Seppälä), FMI (Laakso)

JS3 Platforms included: FerryBox: Silja Serenade and Finnmaid (SYKE, FMI), Utö Observatory (FMI, SYKE), Gliders (FMI), profiling buoys (FMI, SYKE), Argo floats (FMI), monitoring by R/V (All), calibration lab (SYKE).

Other data sources and external partners for implementation: The possibility to open a TA in collaboration with AQUACOSM-plus will be explored, allowing other research groups to join the experiment.

Overall timetable of action: Planning of the experiment in 2021, experiment period in summer 2022.

Description of action: The Action will discover how observations and experimentation may improve our knowledge of ecosystem responses to perturbations. It includes analyses of existing time series, to understand which are the frequencies, ranges and durations of extreme events (e.g. unusual temperature shifts, extreme riverine loads), jointly with observation and experimental communities. This work is also shared between NW-MED PSS and CRETAN PSS, with a similar approach.

The experiment is planned for 2022, likely studying the combined effects of temperature and river load of humic materials (to be precise during 2021). Water (4 m3) will be collected from the open Baltic Sea during a research cruise. In the research laboratory, it will be distributed into 12 300-L mesocosm units, which are individually controlled for temperature and light. Mesocosm experiment will last 2-3 weeks and the responses of the plankton system will be followed continuously using AQUABOX-device, developed under the AQUACOSM project, measuring the key biological, chemical and physical variables. The online measurements are supported by an array of laboratory measurements to get relevant insight into plankton processes. The observed shifts in the plankton community will be analysed against trajectories observed in nature.      

Best practices used or developed: Best practices created and used by JERICO-RI and AQUACOSM-RI communities are compared.

Data flows: Experimental data will form a separate package, and made openly available with DOI

Data QC routines: QC routines for continuously collected online experimental data are under scrutiny and the developments benefit from experiences of JERICO-RI

Data management issues: Likely the data will be available through the host institute,

Expected results: Primary result of the Action, jointly with similar Actions under NW-MED PSS and CRETAN PSS is advancing the communication between different coastal marine research disciplines, in studying similar phenomena. The conceptual steps in this collaboration include analysing which types of available observations may support experimental studies, e.g. by showing how common the studied disturbances may be in the region, or which regions may be most affected. Then, the results of the experimentation may guide the observations further, e.g. by showing if the observation capacities are optimal for following such events and their effects. Naturally, the experiment combined with relevant time series of observations is expected to produce relevant and new scientific data and publications.

Users of results: Scientific community, management of seas areas and planning countermeasures

Dissemination of results: Results will be disseminated both in the JERICO-RI and AQUACOSM-RI communities in their annual meetings. Another target group for dissemination are ministries and institutes financing coastal studies, showing that such collaborative schemes may yield very important and focused information for specific questions. Additional dissemination in scientific workshops.  

Links: Strong between PSS-link and link to AQUACOSM-RI community are evident. Additional link to between RI-collaboration in WP2, T2.2, showing how the collaboration within the region and between regions may be arranged.