Research project The regulation of production in the base of the food web in the northern Baltic Sea will be studied using a 30-year time series from environmental monitoring. Improved assessment criteria and reference values will also be developed.
The project aims to increase the understanding of the ecosystem's function and the balance between different organisms in the northern Baltic Sea. It will improve knowledge about and models for how the production of phytoplankton and bacteria at the bottom of the food web affects the size of fish and shellfish stocks. The project also intends to develop production reference values to better assess whether phytoplankton production, growth and their balance are within expected levels. These small organisms form the basis of food for all zooplankton, fish and shellfish in the food web.
The application aims to increase the understanding of ecosystem function and trophic balances in the northern Baltic Sea. Knowledge of bottom-up processes and models that describe the link between basic production in the food web and fish and shellfish will be improved. The project also intends to develop reference values for more reliable assessment criteria for phytoplankton production, bacterioplankton growth and their balance.
Research vessel from Umeå Marine Sciences Centre (UMF) meets the ice
ImageAnna Palmbo-BergmanThe method is based on 30-year ecological time series in the Bothnian Bay and the Bothnian Sea produced by Swedish environmental monitoring. Models for regulation of phytoplankton production, bacterioplankton growth and biomass will be developed using the partial least squares method (PLS) and chronological cluster analysis with the multi-variate software SIMCA. Explanatory variables will include meteorological factors such as global irradiance, marine factors such as nutrient concentrations and pycnocline depth, as well as factors in the catchment area such as river inputs of nutrients and dissolved organic carbon.
Reference values will be developed based on the 30-year time series in accordance with climate practice, considering explanatory variables. Linkage to ecological function will be investigated and implemented where possible with the support of the results from the investigation of regulating factors.
The results are intended to establish assessment criteria for the investigated indicators nationally and internationally. This will support ecosystem-based aquatic environmental management where the Swedish Agency for Water and Marine Management (SWAM), County Administrative Boards, municipalities and international stakeholders (HELCOM, ICES) are target groups. Good assessment criteria increase the reliability of state assessments and action strategies, promote more effective decision-making at the political level and the acceptance of measures among the population. Overall, sustainable management of the marine environment is of significant societal value.
