Optimisation of sand nourishment techniques for restoring ecological valuable tidal flats:Unravelling the importance of bio-physical interactions (outside HZ)

Versie van 24 dec 2016 om 11:33

Sand nourishments are widely used in the coastal environment and have been developed to protect the coast and its ecosystems from erosion and sea level rise. Nowadays mega-nourishments are also being used to restore and maintain valuable ecosystems on tidal flats. The latter requires the nourishment practices to be optimized for being eco-friendly.

It is well-known that the presence / absence of soil animals can have a large effect on the erodibility of sediment. Dumping sediment on an existing tidal flat might directly affect the local communities living in these areas by killing them. Moreover, the sediment used for the nourishment of coastal areas is usually deprived of any living organisms, and thus might alter the bio-physical interactions relative to the originally present sediment or facilitate the establishment of invasive species. There is need to gain a generic mechanistic understanding on (1) how benthic communities may affect the long-term development of sand nourishment, (2) how benthic communities respond to different sand nourishment techniques and (3) how this type of measures may be translated to ecosystem services.

Student opportunities:

A way to examine the effects of soil animals on the erodibility of sediment is to compare the properties of sediment with and without benthos. To do so, a large “defaunation” (soil animals removed) experiment has been implemented in the Schelde estuary and will be monitored monthly over the Summer 2016. This experiment is part of a pilot study relative to the Roggenplaat. Environmental data and benthos samples will be collected and measured to answer the following sub-questions (see section sub projects)