Experimental study of a 3D printing application to produce substrates for coral propagation

• Type: Poster in a National Conference
• Date: 2021-05-05

Authors

Ilse Matus (Author) Other; Jorge Lino (Author) FEUP; Joaquim Góis (Author) FEUP; Augusto Barata da Rocha (Author) FEUP; Rui Neto (Author) FEUP; Carlos Mota (Author) Other

Conference National

IJUP'21

Porto, 5 a 7 de maio de 2021

Scientific classification

CORDIS: Technological sciences > Engineering

FOS: Engineering and technology

Other information

Abstract (EN): Additive Manufacturing provided an innovative method of production for ecology restoration areas, allowing rapid prototyping of substrates with high complexity morphologies, a critical and fundamental attribute to guarantee coral growth and Crustose Coralline Algae. The experimental study has a purpose to prove and qualify the influence of textured surface substrates morphology and chemical composition on the growth and propagation of transplanted corals. It was used Additive Manufacturing and silicone molds for converting three-dimensional samples into limestone mortar with white Portland cement substrates for coral growth. A systematic methodology was established starting with a deep bibliographic research on scientific articles, related books in design, biology and engineering areas and several national and international case studies about implementation of artificial marine structures. Based on literature review, tiles samples were designed and printed with different geometries and textures inspired by soil erosion and nature marine environment. Commercial coral frag tiles were analysed through Scanning Electron Microscopy (SEM) to identify the main chemical elements. Tropical coral species with fast growth rate in captivity were selected namely Montipora Danae; Montipora Confusa and Montipora Undata. The developed substrates were introduced into a closed-circuit aquarium to monitor the coral weekly evolution process and analyse the results obtained. The experimental results provided positive statistical parameters for future implementation tests, concluding that the intensity of textured surface, interfered favourably in the coralline algae biofilm growth. Also, the chemical composition and design of the substrates were determinant factors for successful coral propagation. Recesses and cavities mimic the natural rocks aspect and promote, at the same time, the presence and interaction of other species that favour the richness of the ecosystem.

Language: English

Type (Professor's evaluation): Scientific

Notes: OBJECTIVES - i. Study the 3D printing applications to produce artificial reefs, through a deeply international and national research. ii. List the survival requirements needed for coral species selected during the fragmentation, growth and reproduction process. iii. Research and introduce innovative technologies and materials. iv. Develop substrates for coral propagation. v. Determine an experimental plan to validate the results. vi. Idealize an artificial reef concepts. METHODOLOGY - Tiles samples were designed and 3D printed with different morphologies and textures inspired by nature soil erosion. Commercial coral frag tiles were analysed through Scanning Electron Microscopy (SEM) to identify the main chemical elements. Raw materials and coral species were selected. New base substrates were manufactured and deployed into a closed-circuit aquarium to monitor the coral weekly evolution process and analyses the results obtained. RESULTS - The substrates were monitored weekly by photography record and visual analysis to evaluate the growth evolution according with the Crustose Coralline Algae (CCA) expansion on the tile and coral growth. During the first three weeks the corals were into an adaptation phase. From the fourth week, CCA began to cover the substrates, a positive indicator for the calcium skeleton layer formation and coral settlement. During this week, the substrates whose texture were more pronounced showed a favorable evolution, validating the principle that higher surface complexity with deep recesses, facilitate the CCA propagation and coral growing. Between the fifth and ninth week, Montipora Danae showed a higher growth rate compared to the other species. Corals had growth and covered all tiles with different timings, which provides a positive indicator regarding the nutrients given, mainly composed of calcium carbonate.