AQUACOSM: linking lakes, rivers and oceans across Europe

KOSMOS marine mesocosms off Svalbard in the Arctic Circle. Image: Signe Klavsen
Water connects lives at all scales, supporting human and non-human populations alike, through networks that link Earth’s most remote areas with some of its biggest cities. The ecological inter-connectedness of freshwater and marine habitats – lakes, rivers, estuaries and oceans – is increasingly acknowledged by scientists and water managers. However there is the need for large-scale experimental research in order to better understand the dynamics and threats of these connected aquatic systems.
Scientists from 19 leading research institutes and universities, and two enterprises from 12 countries, across Europe are collaborating on a new project AQUACOSM, a “Network of Leading European AQUAtic MesoCOSM Facilities Connecting Mountains to Oceans from the Arctic to the Mediterranean”. AQUACOSM will support the first systematic large-scale ecological experiments in linked freshwater and marine ecosystems. The project is coordinated and led by Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB) in Germany.
“For more than 100 years, inland water and marine research have largely developed in parallel to each other. Now it’s time to reunite both”, says IGB researcher Jens Nejstgaard, who leads the new EU-funded project. In AQUACOSM, scientists from both marine and freshwater realms are joining up an integrated, international network of experimental infrastructures. Their aim is to significantly improve the quality of experimental data for all types of water. “We want to better coordinate international large-scale experimental research projects, develop good practices together, and open up the freshwater and marine mesocosm research infrastructures for a broader international, interdisciplinary collaboration,” outlines Nejstgaard.

The IGB LakeLab in Lake Stechlin, Germany. Image: HTW Dresden-Oczipka
The project uses a network of experimental mesocosms across Europe. Mesocosms are structures used to recreate variables from the natural environment within controlled, observable conditions. In other words, mesocosms create an ‘ecosystem in minature’, bridging the gap between laboratory work and field studies, where the effects of different climatic and human pressures on the environment can be simulated.
AQUACOSM researchers will examine how different aquatic ecosystems react to environmental impacts caused by global climate change and population growth. “The impact of these stress factors can vary widely within different ecosystems and seasons”, emphasises Nejstgaard. As a result, they have to be investigated in different climatic and geographic regions, using comparable mesocosm experiments and measurement methods. AQUACOSM connects the infrastructures needed to do such experimental research across a range of different European water types, through climatic and geographic zones stretching from the Arctic to the Mediterranean.

The AQUACOSM project team. Image: AQUACOSM
The AQUACOSM experimental infrastructures include tank systems and flow channels on land such as in Lunz am See in Austria, and large free-floating open-ocean facilities such as the Kiel Offshore Mesocosms (KOSMOS) off Svalbard in the Arctic. The IGB-LakeLab in Lake Stechlin, Germany is one of the largest facilities in the world, providing 24 mesocosms, each containing 1,270 m³ of water, supporting research into the impacts of climate change on deep water lakes.
AQUACOSM will offer researchers, both from Europe and further afield, the opportunity to access and use this connected network of mesocosms, as a means of fostering new collaborations and large-scale ecological insights across biomes. This research is intended to feed into networks of stakeholders – water managers and policy makers, for example – as a means of strengthening the protection and restoration of aquatic habitats, both freshwater and marine.