Benthic ecology
Ecological Accompanying Research on Offshore Wind Energy Use on Research Platforms in the North and Baltic Seas (BeoFINO)
Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI)
The buried foundation piles of wind turbine installations generate changes in hydrodynamic conditions in the area surrounding these piles. From the investigation of shipwrecks and artificial reefs, it is known that these hydrodynamic changes may result in the occurrence of underwash, changes in particle size and the accumulation of organic material. The development of seabed communities is critically influenced by the settlement and recruitment of meroplanktonic larvae. These processes are dependent upon hydrography, conditions of sedimentation and the availability of hard substrates. Any change to these parameters, e.g. resulting from offshore construction works, will have a significant influence upon the development of seabed communities. The composition of the soft seabed community will be altered accordingly. The piles also constitute an artificial hard substrate, leading to the settlement of organisms which would otherwise seldom, if ever, be encountered in the soft seabed community.
The object of the "BeoFINO" project was the development of methods and criteria for the investigation of the potential impacts of future offshore wind turbines upon the marine environment. The project has been coordinated by the Alfred Wegener Institute for Polar and Marine Research (AWI).
The BeoFINO project was a constituent element of ancillary research into the exploitation of wind power in the offshore region of the North Sea and Baltic Sea, funded by the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU) .
Activities and goals
Investigation of the following:
- The seasonal development of planktonic larvae and larval populations
- Changes to the seabed community in the vicinity of piles associated with the potential influence of artificial hard substrates
- The recording of settlement processes by the direct photography of a research platform pile
Seabed sampling
Benthic samples have been used to investigate changes to abiotic parameters (including sediment composition) and to the seabed community. The latter has been analyzed on the basis of the spatial distribution of various benthic species and the population of the seabed by planktonic larvae.
Water column sampling
Plankton samples have shown the seasonal composition of plankton and the larval population.
As a result, information has been obtained on the diversity of species and the numbers of meroplanktonic larvae which might potentially settle on the seabed.
Recording of settlement on the pile
Underwater images provide an indication of the composition of species, together with the density, seasonal profile and rate of settlement of organisms on the pile.