Seagrass plays a vital role in climate and coastal protection. Seagrass meadows can store large amounts of CO2, they stabilise coasts against erosion and create a habitat for thousands of species. Seagrass removes the greenhouse gas carbon dioxide from seawater and stores its carbon component in the seabed – at a higher rate than any forest ashore. However, like other coastal ecosystems, seagrass meadows are a highly endangered domain. Ocean warming, over-fertilisation, mass tourism and urban development are endangering seagrass worldwide. The prevailing seagrass species in the southern Baltic Sea, Zostera marina, also faces this major challenge. The collaborative project SeaStore intends to reintroduce seagrass meadows successfully. The likelihood of a successful reintroduction depends on a complex interaction of many factors. Based on preliminary research conducted in Scandinavia, the project investigates all of these factors. SeaStore is a collaborative project involving different universities and facilities, coordinated by Leibniz University Hannover (LUH).
And the project has already produced some impressive results: The seagrass reintroduction efforts in the Baltic Sea initiated within the scope of the project have been a major success. At three locations along the Schleswig-Holstein Baltic coast (Kiel, Maasholm and Geltinger Bucht), more than 3,000 square metres were planted with 12,000 plants that research divers had carefully taken from an intact seagrass meadow beforehand. "After a bit more than one year, a promising development is emerging", says project supervisor Dr. Maike Paul from the Ludwig Franzius Institute of Hydraulic, Estuarine and Coastal Engineering (LuFI) at LUH. At one site, there were initial difficulties, but overall the vegetation density has increased and has expanded more than 25 times in one year. "After one year, it almost corresponds to the density of a natural meadow and can now be easily spotted on satellite images", explains Maike Paul.
The sites and plantings differ in how exposed they are to waves and how many plants were planted per square metre. After planting, the plots have been sampled at regular intervals to measure dispersal, carbon storage, sediment stabilisation and biodiversity – including microbial communities – as well as to assess plant development. The same data will be collected in a natural seagrass meadow to understand differences and similarities between natural and reintroduced seagrass meadows. The sampling will continue intensively until the end of the project in October 2023.
With regard to acceptance and perception in the population, the project team conducts research group discussions and nationwide population surveys on the perception of seagrass meadows compared to other ecosystems. Initial findings show that area expansion through reintroduction is largely viewed positively and as an innovative contribution to carbon storage efforts.
The tools and models from the SeaStore project are intended to help authorities and other involved parties to assess, plan and successfully implement projects to establish seagrass meadows. “Our initial findings successfully demonstrate the feasibility of seagrass reintroduction", says Maike Paul. Therefore, this method could become a promising tool for future coastal management projects.
About SeaStore
The collaborative project “SeaStore: Diversity Enhancement through Seagrass Restoration” was launched in November 2020 and will be concluded in October 2023. SeaStore is in receipt of approximately two million euros of funding provided by the Federal Ministry of Education and Research. In the multidisciplinary collaborative project, researchers from different scientific fields are pursuing the common goal of developing promising methods for the reintroduction of seagrass meadows in the southern Baltic Sea. They aim to develop guidelines that cover all aspects of seagrass restoration: from selecting the right sites as well as suitable seeds or sprouts, to specifications on how these should be planted, to monitoring success and the question of how the coastal population, tourists and other stakeholders can and must be involved in the project in order to increase the prospects of success and public acceptance. LUH (Ludwig Franzius Institute of Hydraulic, Estuarine and Coastal Engineering, Institute of Plastics and Circular Economy) coordinates the collaborative project. Additional project partners include TU Braunschweig, University of Greifswald, the GEOMAR Helmholtz Centre for Ocean Research Kiel, as well as the Kiel Institute for the World Economy.
Further information can be found at www.seegraswiesen.de
Note to editors:
For further information, please contact Dr. Maike Paul, Ludwig Franzius Institute of Hydraulic, Estuarine and Coastal Engineering (Tel. +49 511 762 2584, Email paul@lufi.uni-hannover.de).
