Counteracting climate change: Research consortium sea4soCiety investigates ways to naturally increase carbon storage in coastal ecosystems

As one of a total of six research consortia in the mission "Marine carbon sinks in decarbonization pathways", sea4soCiety will quantify and analyse the storage capacity for "blue carbon" in four different types of coastal ecosystems on the German North Sea and Baltic Sea coasts, in the Caribbean and the Indonesian Sea over the course of its three-year funding phase. Martin Zimmer, Head of the Department of Ecology at ZMT and Professor of Mangrove Ecology at the University of Bremen, is responsible for coordinating the research project.

Vegetation-rich coastal ecosystems of tropical and temperate latitudes, such as mangrove forests, seagrass beds, salt marshes or kelp forests, absorb huge amounts of carbon dioxide (CO₂) from the atmosphere. Mangrove forests in tropical regions alone absorb 40 to 60 million tonnes of carbon annually. That is about as much as road traffic in Germany emits as greenhouse gases per year. The salt marshes of the Wadden Sea on the German North Sea coast store about 20,000 tonnes of carbon annually. The storage of this so-called "blue carbon" is one of the most important services provided by coastal ecosystems.

In recent decades, urbanisation, erosion or pollution have increasingly damaged the properties, processes and services of many ecosystems in coastal regions worldwide. Consequently, the global capacity to compensate for CO₂ emissions by storing "blue carbon" in coastal ecosystems has also declined. The researchers will contribute scientific expertise in coastal ecology, chemistry, sedimentology, geology, hydrodynamics, remote sensing and modelling to quantify the storage capacity of "blue carbon" in seagrass beds, algae, salt marshes and mangrove forests and compare it with the depots of organic material in unvegetated marine sediments.

The origin, stability and dynamics of organic matter are analysed in the field and in the laboratories of the collaborative partners. Satellite data and ship-based measurements are used to determine the biomass on land and underwater in coastal zones. Communication with local societies, modelling and scenarios will make an evaluation of the potential benefits and risks of increasing the area of coastal ecosystems beyond their current stocks possible.

Socio-ecological component of the joint project

According to the researchers, suitable measures should be ecologically feasible, environmentally compatible and legally and ethically unobjectionable. Natural scientists are working closely together with researchers from the fields of human geography, socio-economics, ethics and law in an interdisciplinary network to ensure that the approaches to improving carbon storage in coastal ecosystems meet societal requirements, create additional benefits and are based on broad acceptance. Based on the results of socio-ecological studies, both a roadmap for the sustainable use of marine carbon reservoirs and evidence- and scenario-based recommendations for politics, the private sector and society will be developed. Based on local field research, these proposals will be extrapolated up to scales of national, international and global relevance.

“By increasing the capacity of coastal ecosystems to sequester greenhouse gases and securing additional ecosystem services, the sea4soCiety research network contributes to achieving the goals of the Paris Climate Agreement, the United Nations Framework Convention on Climate Change (UNFCCC) and the United Nations 2030 Agenda,” Martin Zimmer concludes.

For the original press release of the the Leibniz Centre for Tropical Marine Research (ZMT) please click here.