45 p.
This is the author’s November 2007 version of a work accepted for publication by Elsevier. A definitive version was subsequently published in Ocean & Coastal Management, volume 51, issue 10, 2008, pages 659-670, doi:10.1016/j.ocecoaman.2008.07.005. View the publisher's web page for this article at http://dx.doi.org/10.1016/j.ocecoaman.2008.07.005