Elisabeth Riera , Benjamin Mauroy, Patrice Francour, Cédric Hubas

Artificial reefs (AR) must be built according to their objective and show high complexity to mimic the characteristic of natural habitats. To enhance the integration of artificial structures into ecosystems, a new quantitative method has been developed to evaluate their complexity, using 3D computer-aided design (CAD) models of ARs. The method utilizes six metrics: three related to geometric complexity (C-Convexity, P-Packing, and D-Fractal dimension) and three related to informational complexity for sessile organisms (R-Orientation Richness, H-Orientation Diversity, J-Orientation Evenness). This method categorizes artificial reefs based on their complexity and has the potential to aid in designing more effective artificial reefs in the future while providing a quantitative way to analyze the correlation between complexity and diversity on the scale of artificial reefs. Additionally, the method may identify specific complexity thresholds for attracting certain species or achieving particular goals. This approach fills a gap in the current lack of quantitative methods for assessing artificial reef complexity, potentially leading to more effective and ecologically integrated artificial reef designs.