A model approach to estimate the potential for mussel beds in a Wadden Sea area of the German North Sea coast

Abstract

<p>In the awareness of the increasing conciousness regarding the sensitivity, vulnerability, and<br>complexity of near coastal marine ecosystems, including tidal flats, it is imperative to improve the<br>understanding of its individual elements. One of these elements are organisms habitating the<br>seabed, such as mussels.<br>Bivalves - specifically blue mussels (Mytilus edulis) and pacific oysters (Magallana gigas) - besides<br>other smaller organisms are an integral part of the seabed fauna. On the one hand they serve as a<br>basic food resource for a large number of higher trophic level predator. On the other hand they<br>affect the surface structure, stability and composition of the seabed.<br>To better understand the large fluctuations the mussel stocks underwent during the last decades, it is<br>of great benefit to know the environmental conditions of their habitats. Based on the analysis of<br>different physical parameters at known mussel beds, prototypical automated algorithms were<br>developed and used to identify other tidal flat regions with favorable conditions for epibenthic<br>mussels. The input parameters originate from different morphological, hydrodynamical,<br>sedimentological and hydrochemical numerical models. Morphological factors include<br>morphological activity and gradient conditions of the ground surface, hydrodynamical factors<br>include stream velocities, bottom shear stress, wave orbital velocities, energy of wave breaking and<br>duration of tidal flats falling dry during low tide, sedimentological factors include sediment<br>composition and hydrochemical factors include salinity. These parameters were available as<br>products of the mFUND project EasyGSH-DB and were supplemented with additional evaluations.<br>It is expected that the approach of habitat modeling will allow to determine the possibility of initial<br>and long-term settlements of epibenthic mussels by ruling out intertidal or subtidal seabed areas<br>where environmental parameter combinations do not fulfill the necessary requirements.</p>

An Integrated Marine Data Collection for the German Bight – Part I: Subaqueous Geomorphology and Surface Sedimentology

“…SMMS aims to provide consistent and continuous stratigraphical data of the sub-seafloor and adjacent estuaries to further improve the ability of hydrodynamic numerical model systems to assess erosional processes. Additionally, ecological model components (see methodology excerpt in conference presentation Rubel et al, 2020) are developed in connection to the publicly funded KFKI project "Roughness effects of oyster reefs and blue mussel beds in the German Wadden Sea" (BIVA-WATT). With this, we aim to be able to provide the most comprehensive synoptic base and validation data for numerous morphodynamic model systems and other general applications.…”

An integrated marine data collection for the German Bight – Part 1: Subaqueous geomorphology and surface sedimentology (1996–2016)

“…For display purposes, sedimentological maps can be produced by a classification of grid points to their linguistic description of their respective cumulative GSD function. The concept of the generation of a (quasi-)bijective linguistic description from a function (Sievers and Milbradt, 2021) is based on a reversal of initial concepts from Voss (1982) and Naumann et al (2014). It relies on the definition of grain size classes and respective percentages within the cumulative function relative to each other to determine a description that would adequately regenerate the original GSD function.…”