We have now gone through a full week of experimental runs with two ‘exposure’ days on which the water level was lowered to let the plants breathe and to let us work – i.e. carry out our measurements on the plants and the soil surface. But before each time we drain the tank, we have decided to go fishing…. for all the debris and plant matter that has floated to the top during the intervening wave runs. We hope that the amount of material fished out might relate to the intensity of the waves that we have sent over the plants: the more energetic the waves, the more plant matter should float to the surface…
For the purpose of skimming all that is swimming, we use a net suspended on two ropes that is rolled along the flume with two cradles on either side of the tank. All of the material collected in the net is then left to dry, so we can establish its dry weight and compare it with previous ‘fishings’. It all makes the flume smell as good as the seaside!