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Overarching themes

Session themes for BSSC2021

The Baltic Sea Science Congress invites scientists studying the Baltic Sea, or similar coastal sea systems, to share their results at this international and interdisciplinary forum!
We also invite the sharing of research from other coastal seas that is of general relevance to the topic of the Congress. In particular, we encourage presentations focusing on coastal and marginal seas that contribute to the UN Decade of Ocean Science for Sustainable Development. 

BSSC2021 focuses on five overarching themes:

Theme 1: Transition
Theme 2: Ecosystems
Theme 3: Contaminants
Theme 4: New technologies
Theme 5: Stewardship

For detailed descriptions of the themes, please see below or in the menu to the left.


Theme 1: Transitions

The Baltic Sea in transition – past, present and future

The Baltic Sea constitutes a young ecosystem, which is constantly undergoing changes in response to climate variations and human activities. These changes affect all physical, chemical and biological components of the system as well as their interactions.

The theme focuses on understanding the past to describe the present situation and possibly predict the future behaviour of the Baltic Sea. This includes descriptive and experimental studies, using observations and/or models that aim to better understand the dynamic behaviour of the Baltic Sea, its coastal ecosystems and watersheds. The sessions under this theme will address topical questions such as:

  • What can we learn about climate and ecosystem changes in the Baltic Sea region and their variability    during the Holocene from stratigraphic studies?
  • How has the Baltic Sea changed over the last century and what is the role of natural versus human-      driven variations?
  • How will the Baltic Sea behave in a future warmer climate with changing salinity, less sea ice, less          oxygen, and lower pH?
  • Are extreme events and natural hazards becoming the norm and how will this affect the Baltic Sea?
  • Will land-sea interactions change in the near future?
  • How has the cycling of key elements changed over time and what are their projections for the future?
  • How do invasive species affect the ecosystem on the short and long terms?
  • Are biological communities becoming more or less complex (diverse, stable etc.) over time?
  • How will the Baltic Sea organisms be affected by the future environmental changes?
  • Are the expected changes irreversible and do we have early-warning indicators for potential regime        shifts?
  • How do changes in the Baltic Sea compare to other ecosystems?

Theme 2: Ecosystems

Baltic ecosystems – processes, functioning and diversity

The Baltic Sea is one of the world’s largest brackish inland seas and its coastal ecosystems display large salinity gradients. Temperature and ice conditions change markedly with latitudes. Geology and land use vary substantially in the drainage area with significant impact on material fluxes from land to sea. These settings allow for a diverse range of biological communities and ecosystem configurations.

The theme focuses on understanding processes and functioning of the Baltic Sea watershed, coastal zone and open waters, including all aspects of eutrophication, acidification and food-web alteration. This includes studies of hydrodynamics, biogeochemistry, geology, and biology that aim to improve our understanding of the complex interplay of different drivers and processes shaping these ecosystems. Interdisciplinary studies are particularly welcome. The sessions under this theme will address key questions such as:

  • How do saltwater inflows, upwelling and mixing control the stratification and circulation patterns in the  Baltic Sea?
  • What is the role of sub-mesoscale eddies for the transport of energy in the Baltic Sea?
  • How will changes in hydrodynamics affect the marine ecosystem?
  • What is the ecological and biogeochemical role of the submarine groundwater discharge?
  • Do multiple pressures have synergistic, antagonistic or additive effects on organisms, communities and  ecosystems?
  • How is benthic-pelagic coupling varying along the environmental gradients and affecting                    biogeochemical processes?
  • How is biodiversity linked to ecosystem functioning and sustainability?
  • Are the Baltic Sea and its coastal systems sources or sinks for greenhouse gases?
  • What are the important processes regulating land-sea interaction?
  • Are there ecological “hotspots” for biological communities and biogeochemical cycles?
  • What is the role of bottom-up versus top-down control of food webs in the Baltic region?
  • Are there significant feedback mechanisms between biogeochemical processes and organization of    biological communities?
  • How does the functioning of the Baltic Sea compare with other similar ecosystems?     

Theme 3: Contaminants

Contaminants and potential consequences

New chemicals and other substances are introduced at unprecedented rates along with legacy pollutants that are still circulating and impacting the Baltic Sea. The combination of the large catchment area and the low water exchange rate allows for higher concentrations of contaminants to build up in the Baltic Sea compared to other marine areas. Organisms inhabiting the Baltic Sea are exposed to complex mixtures of diverse chemicals with unknown consequences for the overall ecosystem functioning.

The theme focuses on identifying potential new sources and effects of contaminants to the marine environment. This includes studies assessing short-term (acute), medium-term and long-term effects of different harmful substances (e.g. heavy metals, radionuclides, dumped chemical munition, persistent organic pollutants, emerging pollutants such as pharmaceuticals and personal care products, nanoparticles and plastics) at the level of organisms, communities, ecosystem as well as on ecosystem functioning. Studies on bioaccumulation, biomagnification and associated biological effects are welcome. The sessions under this theme will address basic questions such as:

  • What are the emerging chemical threats (pharmaceuticals, personal care products, nanoparticles, etc.) to the Baltic Sea ecosystem?
  • What are the major sources of harmful substances in the marine environment?
  • How do contaminants interact with varying salinity and oxygen levels, other chemicals, and biogeochemical processes?
  • What are the ecological consequences of contaminants for species, communities, biological diversity and ecosystem functioning?
  • How do harmful substances, including microplastics, accumulate through the food web?
  • How do we assess and mitigate harmful effects of contaminants?
  • What environmental conditions favour degradation and transformation of contaminants?
  • How do the impacts of contaminants of emerging concern compare with the impacts seen in other ecosystems?

Theme 4: New technologies

Introducing new technologies

The continuous development of new technologies enhances the potential for improving our understanding of marine processes and the state of the Baltic Sea. This involves omics approaches, in-situ sensors, remote sensing, autonomous underwater vehicles, buoys and platforms as well as infrastructure and algorithms to facilitate access to information.

The theme focuses on presenting novel techniques supporting research and monitoring, with emphasis on their potentials as well as limitations/challenges. This includes studies of applying new technologies under various conditions and the experiences gained. Studies that address cost-benefit analyses of implementing new technologies are particularly welcome. The sessions under this theme will address urgent questions such as:

  • What can we learn about ecosystem processes and functioning using molecular genetic approaches?
  • What are the potentials for machine learning in marine science?
  • Can in-situ imaging techniques supplement or replace lab-based taxonomical identification?
  • Can we use remote sensing for habitat mapping?
  • Will AUVs and drones gradually replace traditional shipboard sampling?
  • How will gliders, Argo floats, use of commercial ships, and fixed profiling platforms improve the knowledge on ecosystem functioning?
  • Can the smart combination of long-term traditional measurements and novel methodologies enhance our understanding of the dynamics of coastal and open sea processes?
  • How can we improve quality control of high-frequency data?
  • How can new technologies be adopted within the HELCOM monitoring strategies?
  • How do these technologies in the Baltic Sea compare with those used in other ecosystems?

Theme 5: Stewardship

Stewardship for the Baltic Sea

The Baltic Sea is exposed to multiple pressures, of which some can be managed on a regional level whereas others require global actions. The Baltic Sea has a unique history of managing different pressures through international agreements on emissions, maritime activities and fisheries. Effective management of human activities in the Baltic, today and in the future, is needed to ensure a sustainable use of ecosystem services.

This interdisciplinary theme focuses on measures for managing human activities and the effects they have on the ecosystem. The theme also addresses mitigation measures for pressures that can only be partially managed. Studies addressing the cost-efficiency of different management options and studies considering management from an integrative holistic socio-ecological view are particularly welcome. The sessions under this theme will address timely questions such as:

  • What are the cost-effective measures and the best policy instruments for controlling inputs of nutrients and other pollutants?
  • How do we determine the operational targets for management?
  • Is it possible to valuate ecosystem services and how?
  • How can we manage conflicting interests through marine spatial planning?
  • How can the blue economy be developed in a sustainable way?
  • How can the inherent uncertainty unpinning scientific advices be incorporated in management?
  • How can communication and engagement between stakeholders and scientists be improved?
  • How do we improve ocean and watershed literacy in a Baltic context?
  • How can scientist engage with the public to define research questions and approaches?
  • What can the Baltic region learn from other regions?