Blue is the New Green – Harnessing Urban Coastal Infrastructure for Ecological Enhancement

With two thirds of the human population concentrated around coastlines (Creel, 2003), accelerated coastal development and changes to natural coastlines are inevitable. Throughout the years natural coastlines undergo severe changes, and in many cases are completely overtaken by man-made infrastructure such as ports, coastal defense measures, power plants, industrial facilities, and residential properties. The proliferation of hardened shorelines is also fuelled by processes related to global climate change, sea level rise and ongoing increase in the frequency and magnitude of extreme weather events.

As most marine flora and fauna reside in coastal areas, anthropogenic changes to coastlines are one of the key reasons for loss of coastal habitats and for changes in species assemblage, richness, and biodiversity (Dugan et al., 2011). While coastal infrastructure such as seawalls or breakwaters add significant amounts of hard substrate open to colonization by marine organisms, these man-made structures do not support similar species assemblages to those of natural coastal and marine habitats, and are often associated with nuisance and invasive species (Firth et al., 2014b). These differences are greatly associated to design and material features related to high inclination, low structural complexity, high homogeneity, and different artificial substrate properties, all of which are rarely found, or do not exist in natural habitats (Perkol-Finkel and Sella, 2014).