Macroalgal composition and community structure of the largest rhodolith beds in the world
- 343 Downloads
The Abrolhos Bank, encompassing a wide portion of the Brazilian continental shelf, harbors the world's largest rhodolith bed, which plays an important role in calcium carbonate production in the South Atlantic Ocean. Little is known about the community structure and species composition of this habitat. The aim of this study was to test the hypothesis that latitudinal differences exist in the community structure of rhodolith beds and their associated flora along the Abrolhos Bank. We sampled a total of 33 sites of rhodolith beds located in three regions—northern, central, and southern—of the Abrolhos Bank between depths of 20 and 70 m. Rhodolith density (rhod. m−2) within the beds ranged from 990 ± 347.6 to 57 ± 18.7, with mean diameter ranging from 9.4 ± 3.2 to 3.1 ± 1.4 cm. A total of 146 macroalgae species were identified, including 14 rhodolith-forming species of crustose coralline algae. Abrolhos Bank supports the world’s greatest species richness of rhodolith-forming CCA, with regional distinctiveness. Observed differences in bed structure among regions can be related to differences in shelf width, slope and depth. The studied rhodolith beds constitute a unique habitat supporting a distinctive diversity of associated organisms, and thus require special attention. We highlight the importance of local and regional differences for defining appropriate conservation strategies to protect the rhodolith bed diversity of Abrolhos Bank.
KeywordsAbrolhos Bank Mesophotic Percentage cover Associated flora Crustose coralline algae
We thank Conservation International Brasil for logistical assistance. Financial support was provided by the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) to GMAF, RBFF and RLM; by Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) to GMAF; BRASOIL to Rede Abrolhos; and Fundação de Amparo à Pesquisa e Inovação do Espírito Santo (FAPES) to ACB.
RGB, DPA and PSB acknowledge post-graduate fellowships from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) and from FAPERJ.
We are grateful to the reviewers for their comments that improved the final version of the manuscript.
- Amado-Filho GM, Maneveldt G, Marins BV, Manso RCC, Pacheco MR, Guimarães SPB (2007) Structure of rhodolith beds from a depth gradient of 4 to 55 meters at the south of Espírito Santo State coast, Brazil. Cienc Mar 33(4):399–410Google Scholar
- Clarke KR, Warwick RM (1994) Change in marine communities: an approach to statistical analysis and interpretation. Plymouth Marine Laboratory, PlymouthGoogle Scholar
- Foster MS, McConnico LM, Lundsten L, Wadsworth T, Kimball T et al (2007) Diversity and natural history of a Lithothamnion muelleri-Sargassum horridum community in the Gulf of California. Cienc Mar 33(4):367–384Google Scholar
- Foster M, Amado-Filho GM, Steller D, Riosmena-Rodriguez R, Kamenos N (2013) Rhodoliths and rhodoliths beds. Contribution of SCUBA diving to research and discovery in marine environments, vol 39, 39th edn. Smithsonian Institution Scholarly Press, Washington D.C, pp 143–156Google Scholar
- Gonchorosky J, Sales G, Belém MJC, Castro CB (1989) Importance, establishment and management plan of the Parque Nacional Marinho dos Abrolhos, Brazil. In: Neves C (ed) Coastlines of Brazil. American Society of Civil Engineers, New York, pp 185–194Google Scholar
- Harvey AS, Woelkerling WJ (2007) A guide to nongeniculate coralline red algal (Corallinales, Rhodophyta) rhodolith identification. Cienc Mar 33(4):411–426Google Scholar
- Milliman JD and Amaral CAB (1974) Economic potential of Brazilian continental margin sediments. Anais do XXVIII Congresso Brasileiro de Geologia 3:335–344Google Scholar
- Steller DL, Hernández-Ayón JM, Riosmena-Rodríguez R, Cabello-Pasini A (2007) Effect of temperature on photosynthesis, growth and calcification rates of free-living coralline algae Lithophyllum margaritae. Cienc Mar 33(4):441–456Google Scholar
- Zar JH (1999) Biostatistical analysis, 4th edn. Prentice-Hall, New JerseyGoogle Scholar