Effect of artificial seagrass on hydrodynamic thresholds for the early establishment of Zostera marina

authored by: Jana Carus, Carmen Arndt, Tjeerd Bouma, Boris Schröder, Maike Paul
Abstract: Seagrass meadows have disappeared on many coastal sections due to anthropogenic disturbances, diseases, and/or eutrophication. To facilitate informed seagrass restoration, we i) quantified the hydrodynamic dislodgement thresholds for newly transplanted Z. marina shoots, and ii) tested the effect of artificial seagrass (ASG) as a hydrodynamic protection measure. Experiments were carried out by planting Z. marina rhizomes with living shoots into a sediment bed and exposing them to a range of wave and current conditions in a flume. The use of ASG significantly reduced wave height, as well as current velocity. The applied waves led to the development of ripples whereas currents led to erosion of the sediment bed. The number of shoots that were uprooted and dislodged increased with increasing bed shear stress and erosion. By reducing bed shear stress, the ASG raised the input current velocity threshold, which the transplanted shoots were able to withstand. The present study offers insight into the effect of artificial seagrass (ASG) on wave and current attenuation, as well as sediment erosion and shoot dislodgement. Our results help to inform the setting of hydrodynamic thresholds for the early establishment of Z. marina and to define the improvement of hydrodynamic conditions by ASG.
Organisation(s): Ludwig-Franzius-Institute of Hydraulics, Estuarine and Coastal Engineering
External Organisation(s): Technische Universität Braunschweig
German Federal Institute of Hydrology (BfG)
University of Applied Sciences and Arts Hannover (HsH)
Royal Netherlands Institute for Sea Research - NIOZ
Utrecht University
Berlin-Brandenburg Institute of Advanced Biodiversity Research
Type: Article
Journal: Journal of Ecohydraulics
Volume: 7
Pages: 17-27
No. of pages: 11
ISSN: 2470-5357
Publication date: 2022
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Civil and Structural Engineering, Water Science and Technology
Sustainable Development Goals: SDG 14 - Life Below Water
Electronic version(s): https://doi.org/10.1080/24705357.2020.1858197 (Access: Closed)
https://dspace.library.uu.nl/handle/1874/421126 (Access: Open)