Linking the morphology and ecology of subtidal soft-bottom marine benthic habitats

Linking the morphology and ecology of subtidal soft-bottom marine benthic habitats: A novel multiscale approach

Mestdagh, S.M.F. (Universiteit Utrecht)
Amiri Simkooei, A. (TU Delft Aircraft Noise and Climate Effects; University of Isfahan)
van der Reijden, Karin J. (Rijksuniversiteit Groningen)
Koop, L. (TU Delft Aircraft Noise and Climate Effects)
O'Flynn, Sarah (Universiteit Utrecht)
Snellen, M. (TU Delft Aircraft Noise and Climate Effects)
Van Sluis, Christiaan (The North Sea Foundation)
Govers, Laura L. (Rijksuniversiteit Groningen; NIOZ Royal Netherlands Institute for Sea Research)
Simons, D.G. (TU Delft Aircraft Noise and Climate Effects)
Herman, P.M.J. (TU Delft Hydraulic Engineering; TU Delft Environmental Fluid Mechanics; Deltares)
Olff, Han (Rijksuniversiteit Groningen)
Ysebaert, Tom (Universiteit Utrecht; Wageningen University & Research)

Hydraulic Engineering

2020-06-05

High-resolution surveying techniques of subtidal soft-bottom seafloor habitats show higher small-scale variation in topography and sediment type than previously thought, but the ecological relevance of this variation remains unclear. In addition, high-resolution surveys of benthic fauna show a large spatial variability in community composition, but this has yet poorly been linked to seafloor morphology and sediment composition. For instance, on soft-bottom coastal shelves, hydrodynamic forces from winds and tidal currents can cause nested multiscale morphological features ranging from metre-scale (mega)ripples, to sand waves and kilometre-scale linear sandbanks. This multiscale habitat heterogeneity is generally disregarded in the ecological assessments of benthic habitats. We therefore developed and tested a novel multiscale assessment toolbox that combines standard bathymetry, multibeam backscatter classification, video surveying of epibenthos and box core samples of sediment and macrobenthos. In a study on the Brown Bank, a sandbank in the southern North Sea, we found that these methods are greatly complementary and allow for more detail in the interpretation of benthic surveys. Acoustic and video data characterised the seafloor surface and subsurface, and macrobenthos communities were found to be structured by both sandbank and sand wave topography. We found indications that acoustic techniques can be used to determine the location of epibenthic reefs. The multiscale assessment toolbox furthermore allows formulating recommendations for conservation management related to the impact of sea floor disturbances through dredging and trawling.

Macrobenthos
Multibeam sonar
Sand waves
Sandbanks
Seafloor morphology
Video transect

http://resolver.tudelft.nl/uuid:64e0135b-34ef-4b22-89c9-15d85b9b83eb

https://doi.org/10.1016/j.ecss.2020.106687

0272-7714

Estuarine, Coastal and Shelf Science, 238

Institutional Repository

journal article

© 2020 S.M.F. Mestdagh, A. Amiri Simkooei, Karin J. van der Reijden, L. Koop, Sarah O'Flynn, M. Snellen, Christiaan Van Sluis, Laura L. Govers, D.G. Simons, P.M.J. Herman, Han Olff, Tom Ysebaert