Impactos de um ambiente em mudança nos recifes de corais marginais do Oceano Atlântico Tropical
Novo artigo publicado na revista Ocean and Coastal Management pelo GT1.2 (Recifes e Ecossistemas Coralinos), intitulado “Impacts of a changing environment on marginal coral reefs in the Tropical Southwestern Atlantic”, de autoria de Marcelo Oliveira Soares, Sergio Rossi, Anne Rebouças Gurgel, Caroline Costa Lucas, Tallita Cruz Lopes Tavares, Beatriz Diniz, Caroline Vieira Feitosa, Emanuelle Fontenele Rabelo, Pedro Henrique Cipresso Pereira, Ruy Kenji Papa de Kikuchi, Zelinda M.A.N. Leão, Igor Cristino Silva Cruz, Pedro Bastos de Macedo Carneiro, Lorenzo Alvarez-Filip, discute os efeitos de múltiplas pressões sobre os recifes brasileiros.
Uma ampla avaliação revela que eventos de branqueamento afetaram 26 espécies nos últimos 26 anos (1994–2020). Entre 1994 e 2018 nenhuma espécie sofreu mortalidade em massa após o branqueamento. No entanto, as ondas de calor recentes e intensas de 2019 e 2020 causaram altas taxas de mortalidade em vários corais mostrando que esses recifes não são protegidos a longo prazo e nem refúgios universais. Essas mudanças e outros fatores como pesca🪝, urbanização, mineração, derramamentos de óleo, aumento da sedimentação, ondas de calor, lixo marinho, contaminação urbana, efluentes agrícolas e industriais e espécies invasoras são as pressões mais severas.
O artigo também discute a "hipótese de refúgio do recife brasileiro" a qual poderia ser parcialmente aplicada para alguns corais resistentes ao estresse durante distúrbios agudos (refúgio de curto prazo). No entanto, tal fato não garante que os recifes brasileiros devem ser assumidos como um ecossistema que servirá de refúgio contra as mudanças climáticas.
Por fim, os autores argumentam que é essencial a adoção de estratégias de gestão a nível local e global.
Acesse e compartilhe o artigo completo pelo link: https://authors.elsevier.com/a/1d9-K3RKK-qP4f
RESUMO
The peculiar shallow-water reefs of the Tropical Southwestern Atlantic Ocean have thrived in conditions considered suboptimal (e.g., moderate turbidity, higher level of nutrients, and resuspension of sediments) under the optics of classical coral reefs. Recently, these marginal reefs have been hypothesized to provide climate-change refugia from natural and anthropogenic impacts; yet with little empirical evidence. Therefore, in this article we discuss the known effects of multiple pressures on the Brazilian reefs. A wide evaluation of the peer reviewed literature reported that bleaching events affected 26 species of scleractinians, hydrocorals, octocorals, and zoanthids in turbidzone reefs over the last 26 years (1994–2020) in the Tropical SW Atlantic Brazil. Between 1994 and 2018 no species suffered post-bleaching mass mortality. However, the recent and intense heatwaves of 2019 and 2020 caused higher mortality rates in several key foundation corals (e.g., Millepora alcicornis, Millepora braziliensis, and Mussismilia harttii) showing that the SW Atlantic reefs are not long-term protected and universal refuges. Moreover, other direct and indirect human pressures threaten these tropical reefs. Local and regional (e.g., pollution and fisheries) and large-scale pressures (e.g., global warming and marine heatwaves) act simultaneously on the health of these reefs, which intensifies negative species-specific impacts. We outline the occurrence of pressures that have been important factors responsible for the reduction in species richness and reef fish biomass, changing geoecological functions, altered reef composition and dominant morpho-functional groups, as well as phase shifts. Along with large-scale climatic changes, such as heatwaves, fisheries, urbanization, mining disasters, oil spills, increased sedimentation, increased warming, marine debris, contamination by domestic, agricultural, and industrial effluents, and introduction of invasive species are likely the most severe pressures on Brazilian reefs. We discuss that the “Brazilian reef refuge hypothesis” could be partially applied for some stress-tolerant massive corals during acute disturbances (short-term refuge); yet should not be assumed as a reef ecosystem-wide feature under ongoing environmental change. Therefore, we argue that it is essential to alleviate the main local and regional human impacts and to adopt resilient-based management strategies at local and global scales to protect the lowfunctional redundancy and higher endemism of these unique marginal coral reefs.