It has been a busy Monday at GWK with the installation of the first set of plant pallets in the flume, last minute adjustments and the first reference measurements for plant and soil surface parameters. Of course everything took longer than during the trial last week, but given that something like this has never been done before, the detailed planning paid off and it all went smoothly. The pallets were arranged in predefined rows and then graciously hovered (by hoist) into the flume. Once set in their dedicated slots in the concrete platform, they were fixed with metal plates to ensure a smooth transition from the surrounding concrete to the pallet’s soil.
At the end of the day, the five rows of plant pallets, all representing different stages of salt marsh development from individual seedlings, via tussocks and closed canopies to small cliffs, were installed. In addition, some of the rows are also composed of different plant species which are typical for brackish or more saline marshes. And some of the pallets are covered with biodegradable grates designed to provide protection from erosion. This broad spectrum of species and development stages will allow us to determine the soil stabilising potential of salt marshes and results will be applicable to a broad range of brackish and saline marshes in northern Europe.
Although the overall focus of these experiments in on soil stability, we are fully aware that the waves will not simply pass by the plants without any effect. For this reason we are determining plant parameters such as biomass distribution (both in the horizontal and in the vertical) and the angle at which the seedlings protrude from the soil’s surface. These measurements get done prior to the first test and then after each experimental run. It will be exciting to assess how the above ground biomass of plants is changing during the course of our experiments.
We now stand by for the first inundation and the switching on of the wave generator for the first waves…