OR ELSE: Operational Recommendations for Ecosystem-based Large-scale Sand Extraction

Sand and gravel are amongst the most extracted resources worldwide, exceeding fossil fuels and biomass. Sand extraction is expected to increase drastically to ensure natural protection of sandy coasts against flooding and for extensive infrastructure projects. Large-scale marine sand extraction leads to important ecosystem effects through changes in flows and sediments, and physical disturbance of benthic habitats. Changes in connectivity between spawning and nursery areas in combination with changes in nearshore food availability due to large-scale extractions may influence fish population dynamics. Sand nourishments are, and will remain, a key element in the Dutch coastal management strategy. The Netherlands is extracting relatively large volumes of sand and is faced with the challenge of making optimal choices to minimise the ecological impacts, while still meeting the national demands for sand. Marine ecosystem services provide financial revenue to fisheries and industries. While it is feasible to design extractions in a way that minimises or prevents loss of ecological and economic wealth, this requires knowledge of ecological changes related to excavation. We will study, for the first time in unison between stakeholders, the governance linkages between the fisheries sector and sand extraction with the goal to optimise large-scale sand extraction designs to benefit ecology and economy. Measurements and model predictions of hydrodynamics and morphodynamics will be integrated with species and population models in a Digital Twin of the Dutch North Sea, to assess effects on the marine environment and fisheries. With the aid of a Sand Extraction Serious Game we will develop operational recommendations for future ecological large-scale sand extraction that support policymakers, the dredging industry, nature organisations, scientists and the fisheries sector on ecosystem-based sustainable sand extraction, to be applied in the Netherlands and abroad.