Human activities at sea may have a wide range of impacts on our coastal areas and on the seabed. Offshore sand and gravel extraction, beach nourishment, construction work, oil and gas exploration, trawling, dumping of seabed materials, ships and tourism all contribute to changes in the balance of the ecosystem and the dynamics of the sediments. The consequences are increases in coastal erosion, dredging and sediment migration. Also infrastructure such as oil rigs, submarine cables, pipelines and artificial islands can physically harm a sensitive ecosystem. Further, chemical spills for instance from leaking pipelines and oil spills from ships can affect the ecosystem.
Results from even small-scale, local activities have proved to substantially affect the morphology and the biodiversity of coastal areas as well as less shallow marine areas.
Human activities disturbing the seabed have not previously been subject to integrated strategic management and planning including complete deliberation of regional and long-distance impacts on for instance coastal areas. In future, besides giving us new knowledge, the mapping of potentially cumulative impacts of human activities is expected to provide us with a foundation for evidence-based management of the environment and nature at sea.
A more holistic approach to the planning of the marine area has been the starting point of EU’s Maritime Spatial Planning directive, which was adopted in 2014. According to this directive, Denmark must prepare a Maritime plan for the Danish offshore areas to be implemented no later than in 2021. This is why the Danish law on Maritime Spatial Planning (Havplanen) was passed on 1 July 2016, the aims of which are to promote economical growth, develop sea areas and exploit the marine resources on a sustainable foundation as well as improve the environment. The sectors and stakeholders affected by the maritime planning are: ocean energy (e.g. oil, gas and wind power), maritime transport, fishing, aqua culture, extraction of raw materials (e.g. gravel) and conservation, protection and improvement of the environment.
At GEUS does not carry out maritime spatial planning, but we contribute with a series of geological basic data required to describe the seabed’s sediments. GEUS aims to become an essential partner working together with other maritime research institutions to describe maritime activities and quantify the effects on the maritime environment.
GEUS’ contributions
Mapping of the raw materials sand and gravel and the establishment of a raw material database (MARTA) which has been developed further for the raw material industry and the Danish Environmental Protection Agency’s management of the raw material law.
During the last 6–7 years habitat spatial mapping has also become an important activity for GEUS, including reestablishment of reefs. In the coming years the habitat mapping will continue at EU level in EMODnet III and in the EU BONUS project ECOMAP. For the Environmental Protection Agency, we have mapped Natura 2000 areas and we contribute to the implementation of the EU Maritime Strategic directive.
Mapping of the seabed in connection with the establishment of offshore installations such as submarine cables and wind power parks.
GEUS has developed a concept for maritime archeological pilot surveys, where geological models help find maritime archeological hot spots. A similar multi-disciplinary, best-practice EU project (SASMAP) has recently been concluded.
Studies related to climate have traditionally focused on the Danish waters and the Baltic Sea, where EU projects, IODP and Geocenter Denmark projects have been the principal. In future, the marine geological climate projects will focus on basin studies, combining the geological basin development history with climate proxy, which can describe sediment environments and their climate development histories.
The geology of the coastal zone is studied for different purposes, such as groundwater leaking out on the seabed and saltwater intrusion. Coast classification and vulnerability to erosion are also relevant, where coastal remote-sensing studies (Lidar and multi beam) in 3D can contribute with data important to society. This may be in connection with changes in the environment and the future development of the coast, e.g. when mapping the distribution of eelgrass. The public’s increased use of coastal areas and the need for maritime spatial planning (Havplanen) will require that we know more about the development in the so-called white zone.
We envision great opportunities in future projects, where GEUS will get a central role in collecting marin-geological data in combination with mapping and setting up geological models for evidence-based management of human activities in balance with the maritime environment and nature at sea.