Abstracts of plenary lectures

Thematic session: “Main stressors and their impact on ecosystem health”

The impacts, detection, prediction and management of endogenic and exogenic stressors on marine environmental health
Michael Elliott1, 2, Krysia Mazik1, Anita Franco3
1 Department of Biological and Marine Sciences, University of Hull, Hull, HU6 7RX, UK
2 International Estuarine & Coastal Specialists Ltd., Leven, HU17 5LQ, UK
3 Anita Franco Estuarine and Marine Ecological Consultant, Hull, HU5 3SF, UK

Stressors on marine individuals, populations, communities and ecosystems within a sea area emanate from two sources and may be regarded as pressures; these are defined as the mechanisms of causing change and so which need to be managed to prevent damage to these systems. Firstly, what may be called endogenic managed pressures, in which the causes and consequences both originate from inside the sea area being managed – these include, for example, smothering of the seabed by trawling and dredging, and increased nutrients leading to eutrophication. The exogenic unmanaged pressures originate from outside the sea area being managed and by definition only their consequences are managed within the area whilst their causes require to be managed by wider measures, even as global levels as with climate heating. These pressures include sea-level rise, ocean acidification, increased warming and the introduction of alien species. The talk indicates the methods for the monitoring, assessment and reporting of these pressures and the tools for predicting the effects as a precursor to marine management. The latter tools include the suite of empirical and deterministic numerical models and indicators and rules-based decision support systems. Finally, the place of these tools in marine management and the implementation of European marine Directives and the OSPAR and HELCOM Regional Seas Conventions will be explained.


Thematic session: “Diversity and physiology of marine organisms. Is there still anything to discover?”

Questions and approaches around climate change and impacts in the ocean: a physiologist’s view
Hans-Otto Pörtner
Alfred-Wegener-Institute, Bremerhaven, Am Handelshafen 12, 27570, Germany

Climate change drivers in the ocean entail ocean warming, acidification and loss of oxygen due to warming and enhanced stratification. These drivers individually and together affect ocean life. While some approaches compare the effect size of these individual drivers, other approaches strive to develop an integrative view. Based on principle considerations temperature emerges as a master variable shaping the functioning of all life forms in the ocean. Such functioning depends on the thermal performance curve as a reaction norm characterizing individual species and their lifestages. Overlapping thermal performance curves characterize the temperature range at which species can co-exist at ecosystem level. The talk puts each of the drivers into context and puts an emphasis on how ocean oxygen plays a role in the thermal tolerance and performance of marine animal species.


Thematic session: “Marine molecular ecology – new tools and new findings”

On genetic diversity: new insights from population genomics of marine organisms
Joe Hoffman
Department of Animal Behaviour, University of Bielefeld, Bielefeld, Postfach 100131, 33501 , Germany

Knowledge of the mechanisms shaping the genetic diversity of marine organisms is essential for understanding metapopulation and community dynamics, for predicting future responses to anthropogenic change, for marine protected area design and fisheries management, and for the development of ecological and evolutionary theory. However, the genomic tools needed to unravel those mechanisms have only recently become available. In this talk, I will touch upon some ways in which population genomic data can be used to investigate the factors, both neutral and selective, that shape the genetic diversity of marine populations. I will draw upon examples from our research on diverse marine organisms, including benthic invertebrates and pinnipeds. I will emphasise the importance of combining an integrative approach with advanced genomic analysis techniques to maximise the insights that can be obtained from population genomic data.


Thematic session: “Marine living resources – environmental significance”

Cyanobacteria – are they really so bad?
Hanna Mazur-Marzec
Division of Marine Biotechnology, Institute of Oceanography, University of Gdańsk, Gdynia, al. Marszałka J. Piłsudskiego 46, 81-378, Poland

Cyanobacteria, the Gram-negative bacteria, are important group of primary producers. However, in many eutrophicated aquatic ecosystems, including the Baltic Sea, their blooms pose one of the most serious environmental problems. High biomass of these microorganisms has deleterious effect on the ecological stability of water bodies. In addition, occurrence of cyanobacteria in coastal areas deteriorates sanitary conditions of beaches. Cyanobacteria are also known as producers of a plethora of bioactive compounds, including potent toxins.
In the Division of Marine Biotechnology, University of Gdańsk, high inter and intraspecies metabolic diversity of the Baltic cyanobacteria was documented. It was revealed that the metabolic profile of cyanobacteria is a subpopulation-specific trait. Some of the metabolites can be used as specific chemical markers of high significance in different environmental studies. One example is the reconstruction of thousand-year history of Nodularia spumigena blooms in the Baltic Sea and Norwegian Fjords. In more recent work, the pharmaceutical potential of bioactive cyanobacteria compounds have started to attract increasing attention. In these studies, the ribosomal and non-ribosomal peptides were found to be most promising. Significant number of the peptides produced by Baltic cyanobacteria showed potent anticancer and antiviral activity and revealed an effect on key metabolic enzymes.
In response to the growing interest in cyanobacteria metabolites, a CyanoMetDB was created. This open access data base includes over 2000 compounds and is widely used by scientific community. The study was supported by NCN grant No 2019/33/B/NZ9/02018.


General session

Climate change and marine biodiversity in North Atlantic – competitive exclusion or coexistence?
Jan Marcin Węsławski
Institute of Oceanology Polish Academy of Sciences, Sopot, ul. Powstańców Warszawy 55, 81-712, Poland

The fast warming European Arctic experience two parallel and partly independent phenomena: sea temperature rise and increased transport of waters from lower latitudes. Considering short evolutionary history of the Arctic (less than 1 mln years) majority of marine species there are still close relatives to the boreal ancestor species. The endemic taxa are very scarce, most endemism is on the level of twin species or subspecies and metapopulations. Now the boreal cousins are meeting their twins and by definition they compete for the same niche and habitat, what shall drive the cold climate species to recede. However there are numerous examples, that coexistence is more common that competitive exclusion.