Abstract: Carbon-sequestering composite mixture and methods of carbon sequestration utilizing an aquatic composite structure composed of the composite mixture. The mixture comprises a composite, nanoparticles, and binder. The nanoparticles impact the pore size of the composite mixture, thereby positively impacting the carbon sequestration properties of the mixture. By emplacing an aquatic composite structure composed of such a mixture in an aquatic environment such that it provides erosion mitigation, simultaneous environmental protection effects may be achieved. Further, the binder positively encourages natural ecological growth on the aquatic composite structure, thereby encouraging environmental restoration and encouraging naturally-occurring carbon sequestration from the ecological growth, potentially well past the point at which the aquatic composite structure is unable to continue to sequester carbon.