Active Biopaste for Coral Reef Restoration.

Abstract

Preserving coral reefs is crucial for safeguarding marine biodiversity, global ecosystems, and coastal communities. Coral restoration focuses on farming and transplanting corals back onto reefs. However, traditional attachment methods, such as petroleum-based epoxy, pose environmental risks or provide inefficient affixation. Moreover, maximizing coral growth while farming boosts the restoration rate of the reefs. Hence, an environmentally friendly, conductive hardening bicomponent paste is developed to transplant and anchor corals, provide them with a solid growing substrate, and enable mineral accretion technology (MAT), a strategy to accelerate coral farming. The bicomponent paste consists of bio-based and biodegradable acrylate soybean oil matrix and graphene nanoplatelets fillers. The paste hardens through mixing, transitioning from a Young's modulus of ≃0.1 to ≃60 MPa and reaching a strength of ≃5 MPa. Rheological tests demonstrate the tunability of the crosslinking dynamics of the paste. The paste exhibits a resistivity of 0.1 Ω∙m, with stable electrical properties for over 40 days in seawater. MAT tests show significant enhancement of coral growth rates within two weeks, doubling those of the control group. This paste offers versatility for application in aquaria and nurseries, does not require prone-to-oxidation metallic structures underwater, and can be employed on reefs.