- 101 - ECOLOGICAL MONITORING OF THE BEACH NOURISHMENT PROJECT LOMBARDSIJDE Vanden Eede Sarah and Magda Vincx Research Group Marine Biology, Biology Department, Ghent University, Krijgslaan 281, S8, 9000 Ghent, Belgium E-mail: [email protected] During the last decade, climate change has become a much debated topic. An increase in storms and rising sea levels are particularly problematic for low lying countries like Belgium. Moreover, every kilometer of our coastline is intensively used and needs protection against coastal erosion and flooding. Despite intensive monitoring and maintenance actions, some parts of our coastline do not achieve the required safety level. Soft coastal defence techniques like beach nourishment might help solve the problem. Beach nourishment consists of mechanically or hydraulically placing sand directly on top of an existing beach. As it safeguards the natural dynamics of the coast, beach nourishment has rapidly become a widely applied protective measure in Europe. However, its effect on the soft-sediment macrobenthos remains unclear. Macrobenthos are classified as the seafloor inhabiting benthic forms larger than one millimeter. These organisms play a key role in the wider beach ecosystem. They make up a large part of the diet of intertidal birds and fish and they act as good indicators of pollution and stress. Our research focuses on Lombardsijde beach as it was nourished from March until September 2009. Approximately 650,000m³ of sand was deposited on top of the beach over a distance of around 1,200m. The sand (grain size: 200-250μm) originated from the new fairway to Oostende. The scientific evaluation of ecological effects of any anthropogenic influence can only be performed by comparing the status of the environment before (t0 situation) and after (t1 situation) the influence has taken place. The soft substrates of Lombardsijde beach have been and are being extensively monitored (Welvaert, 2005; Van Ginderdeuren et al.