Understanding the conditionality of ecosystem services: The effect of tidal flat morphology and oyster reef characteristics on sediment stabilization by oyster reefs

Analyses of long-term sediment accretion patterns on natural intertidal oyster reefs at the Oosterschelde basin (The Netherlands) showed that this ecosystem engineering effect is strongest on tidal flats under erosional conditions, lower aspect ratio (i.e., relative long and narrow reefs), relatively closed reefs (i.e., few open patches) and higher coverage of oysters within reef patches. The ability of C. gigas to shape the environment thus depends both on biotic and abiotic conditions, meaning that oyster reefs only work under specific conditions for erosion control. Overall, our results provide baseline understanding for ecosystem management aimed at affecting sediment dynamics, thereby contributing to a better understanding for designing ecosystem-based solutions under different abiotic and biotic conditions. In addition, present study provides a clear example of how we need to gain a better understanding of the conditionality of ecosystem services in general, to be able to create and restore ecosystems for obtaining their services.