WP7: ASG Performance

The Forschungszentrum Küste (FZK) is participating in the SeaArt project with a Work Package (WP) that aims to test the performance of the newly developed artificial seagrass (ASG) at a 1:1 scale under field condtions. To do so, the results of WP 3-6 will be compiled and form the basis for the final prototype experiments in WP7. Therefore, all partners are involved in WP7 to develop and test the most functional artificial seagrass (ASG) for future in-situ application.

At first, potential field sites will be evaluated based on their exposure to hydrodynamics with the aim to find a suitable spot with a wide range of hydrodynamic conditions. Sites with both low as well as high hydrodynamic forces are favored to test the anchoring forces of the ASG and their suitability to improve environmental conditions to support natural seagrass growth. During the campaign the following parameters will be determined:

The Anchoring forces,
Wave and velocity parameters (to quantify the wave attenuation),
Light intensity (to quantify the impact of ASG on light availability for the growing natural seagrass) and
The impact of ASG on sediment transport.

Figure 1: Schematic drawing of the measuring station and the measuring devices to be used in the field. Picture: FKZ

To conduct the field measurements we plan to set up two measuring stations (see Figure 1) in close vicinity to the coast. To measure the above mentioned parameters a number of measuring devices will be fixed, during the whole campaign and temporally, to the stations. While one measuring station is positioned inside the artificial seagrass meadow, a second station is located outside the meadow and serves as a reference station, with which data from “inside” can be compared to (see Figure 2).

It is expected that the hydrodynamic forces will vary within the seagrass meadow depending on the position relative to the meadow edges. Consequently, we plan to conduct the measurements at different positions as indicated in Figure 2.

Figure 2: Sketch of possible arrangement of measuring stations inside the artificial meadow including potential positions of measuring stations. Picture: FKZ

Finally, the data analysis will clarify how effectively our artificial seagrass will influence the environmental conditions to promote natural seagrass growth, but will also be useful to determine the limits of application under extreme conditions. With the help of these measurements the suitability of the prototype in the field will be investigated so that the ASG can finally be deployed for restoration purposes.