Marine biological valuation maps - an example from Belgium
Marine biological valuation maps (BVMs) are maps showing the intrinsic biodiversity value of subzones within a study area. Subzones are defined as subregions within the study area that can be scored relative to each other using a set of valuation criteria (on a continuous or discrete value scale, e.g. high, medium and low value). The size of these subzones depends on the size of the study area, on the biodiversity components under consideration and on the amount of available data and should therefore be decided on a case by case basis. In contrast to the hotspot approach (i.e. identification of priority areas for conservation), we do not want to highlight solely the most valuable subzones.
Such maps would need to make best use of available data sets, compiling and summarizing relevant biological and ecological information for a study area, and allocating an overall biological value to different subzones.
These maps can serve as baseline maps showing the distribution of complex biological and ecological informatio and can be used by policy makers during spatial planning as a kind of “warning systems”. Rather than a general strategy for protecting areas that have some ecological significance, biological valuation is a tool for calling attention to areas which have particularly high ecological or biological significance and to facilitate provision of a greater-than-usual degree of risk aversion in management of activities in such areas. 
Below you can find the marine BVM for the Belgian part of the North Sea. A more detailed version of the map is available here
The map is one of the end results of the BWZee project (2004-2007).
- Derous S., Agardy T., Hillewaert H., Hostens K., Jamieson G., Lieberknecht L., Mees J., Moulaert I., Olenin S., Paelinckx D., Rabaut M., Rachor E., Roff J., Stienen E.W.M., van der Wal J.T., Van Lancker V., Verfaillie E., Vincx M., Weslawski J.M., Degraer S. (2007). A concept for biological valuation in the marine environment. Oceanologia 49 (1). See FLANDERS MARINE INSTITUTE web site at  to download a copy of the paper.
- Derous S., Courtens W., Cuvelier D., Deckers P., Deneudt K., Hillewaert H., Hostens K., Mees J., Moulaert I., Stienen E.W.M., Van Lancker V., Verfaillie E., Vincx M., Degraer S. (2007) A biological valuation map for the Belgian part of the North Sea: BWZee. Final report, Research in the framework of the BSP programme "Sustainable Management of the Sea" - SPSD II, March 2007, pp. 99 (+ Annexes).