Marine biological valuation of the shallow Belgian coastal zone: A space-use conflict example within the context of marine spatial planning

The Belgian coastal zone hosts a complex of space- and resource-use activities with a myriad of pressures.Specifically at the beaches, predictions on sea-level rise, storms and flood risk from the North Sea have led to several big coastal defence projects. Management of sandy beaches is therefore a multifaceted
and complex endeavour, where the interests of several stakeholders need to be combined and where biodiversity should be taken into account.
In this study, the biological value of the shallow Belgian coastal zone was derived based on a detailed and integrated dataset (1995e2011) of all available ecological information on macrobenthos, epibenthos, hyperbenthos and birds. The 67 km Belgian coastline was divided into an across-shore intertidal and
shallow subtidal subzone, and into along-shore subzones of 250 m for benthic components and 3 km for birds. The intrinsic biological value of each subzone was then calculated using the biological valuation method, and the pertained score, ranging from very low to very high, was plotted accordingly in order to
obtain a marine biological valuation map.
Following trends were detected: (1) a strong mosaic pattern of biological value along the coastline; (2) a clear lack of (benthic) data at the eastern part of the Belgian coast; (3) a rather high biological value in around 70% of the shallow subtidal subzones, compared to the intertidal part; and (4) a high/very high
biological value in intertidal zones located immediately to the east of the harbours of Nieuwpoort,Oostende and Zeebrugge.A detailed analysis of protected areas and areas under coastal flood risk indicated that biological valuation maps are very promising management tools for local decision-makers as they allow for an early integration of ‘natural/ecological values’ in policy implementation.