Artificial coastal defence structures - A surrogate of natural rocky structure to enhance coastal biodiversity

The world's 40% of the population lives in coastal areas (<150 km from the sea), and this is set to increase in upcoming years. This urban sprawl leads to the proliferation of artificial coastal defence structures along the coasts to save the populace from coastal erosion, storms, and hurricanes. Deployment of artificial coastal defence structures has direct or indirect impacts on the local and global scenario, but the ecology of artificial habitats was studied poorly. Therefore, the current study aimed to focus on the role of artificial coastal defence structures in enhancing the coastal biodiversity. A total of 228 epibiotic species associated with the artificial coastal defence structures were identified. The study recorded high species richness and diversity of epibenthos in artificial habitats compared to natural habitats. Among various types of artificial habitats, assemblage pattern of epibiotic species in sandstone surfaces differs from non-sandstone surfaces. Apart from the structure surface, local epibenthic biodiversity also plays a significant role in determining the artificial structure assemblages. The length, vertical height, and age of the structures are the major deciding factors in species composition of the structures. The overall study concluded that the artificial coastal defence structures could act as a surrogate surface for epibiotic assemblages. The input of coastal biodiversity component while designing the artificial coastal defence structures can be an added advantage.

Automated summary

The study revealed that artificial coastal defence structures can enhance coastal biodiversity by increasing species richness and diversity of epibiotic species. Different types and characteristics of structures influence the assemblage patterns of epibiotic species, while local epibenthic biodiversity also plays a role in determining the structure assemblages.