Heatwaves and a decrease in turbidity drive coral bleaching in Atlantic marginal equatorial reefs
Caroline Costa Lucas
Carlos Eduardo Peres Teixeira
Marcus Davis Andrade Braga
Francisco Carlos Júnior
Sandra Vieira Paiva
Anne Larisse Gurgel
Sergio Rossi
Marcelo de Oliveira Soares
Abstract
Tropical reefs can occur naturally under suboptimal environmental conditions, where few reef-building corals thrive. These unique reefs are especially important for understanding resistance to global warming, but they are understudied. We studied a coral bleaching event that occurred in turbid reefs (~ 19 m deep) in the equatorial southwestern Atlantic. Mass bleaching was observed in 91% of the Siderastrea stellata colonies in 2020, whereas only 7.7% of the colonies were bleached in 2019 and 10.9% in 2022. The year 2020 had the highest heat stress recorded in this century in this region according to the degree of heating weeks such as 17.6°C-week. In the first semester of 2020, the region also underwent three marine heatwaves (MHWs) above the average temperatures (1.3, 1.5, and 2.0°C). The lowest turbidity and wind speed matched long-lasting, repeated, and severe MHWs. These reef-building corals are dominant under moderate turbid waters and high sea temperature (26–29°C), however they are near the maximum tolerance limit. In this regard, these low-latitude reefs are warming twice as fast (0.2°C/decade) as other regions (e.g., Abrolhos and Coral Coast) (0.1 to 0.13°C/decade) in the South America reef system demonstrating that they cannot be considered climate-change refugia. These results suggest that even turbid marginal reefs and tolerant corals are highly susceptible to mass bleaching, especially when heatwaves and a decrease in turbidity occur simultaneously.
Lucas C.C., Teixeira C.E.P., Braga M.D.A., Júnior F.C., Paiva S.V., Gurgel A.L., Rossi S. and Soares M.d.O. (2023) Heatwaves and a decrease in turbidity drive coral bleaching in Atlantic marginal equatorial reefs. Frontiers in Marine Science 10: 1061488. 10.3389/fmars.2023.1061488
@article{Lucas2023,
Title = {Heatwaves and a decrease in turbidity drive coral bleaching in Atlantic marginal equatorial reefs},
Author = {Lucas, Caroline Costa and Teixeira, Carlos Eduardo Peres and Braga, Marcus Davis Andrade and Júnior, Francisco Carlos and Paiva, Sandra Vieira and Gurgel, Anne Larisse and Rossi, Sergio and Soares, Marcelo de Oliveira},
Editor = {},
Journal = {Frontiers in Marine Science},
Year = {2023},
Pages = {1061488},
Volume = {10},
Doi = {10.3389/fmars.2023.1061488},
Abstract = {Tropical reefs can occur naturally under suboptimal environmental conditions, where few reef-building corals thrive. These unique reefs are especially important for understanding resistance to global warming, but they are understudied. We studied a coral bleaching event that occurred in turbid reefs (~ 19 m deep) in the equatorial southwestern Atlantic. Mass bleaching was observed in 91% of the Siderastrea stellata colonies in 2020, whereas only 7.7% of the colonies were bleached in 2019 and 10.9% in 2022. The year 2020 had the highest heat stress recorded in this century in this region according to the degree of heating weeks such as 17.6°C-week. In the first semester of 2020, the region also underwent three marine heatwaves (MHWs) above the average temperatures (1.3, 1.5, and 2.0°C). The lowest turbidity and wind speed matched long-lasting, repeated, and severe MHWs. These reef-building corals are dominant under moderate turbid waters and high sea temperature (26–29°C), however they are near the maximum tolerance limit. In this regard, these low-latitude reefs are warming twice as fast (0.2°C/decade) as other regions (e.g., Abrolhos and Coral Coast) (0.1 to 0.13°C/decade) in the South America reef system demonstrating that they cannot be considered climate-change refugia. These results suggest that even turbid marginal reefs and tolerant corals are highly susceptible to mass bleaching, especially when heatwaves and a decrease in turbidity occur simultaneously.},
}
TY - JOUR
AU - Lucas, Caroline Costa
AU - Teixeira, Carlos Eduardo Peres
AU - Braga, Marcus Davis Andrade
AU - Júnior, Francisco Carlos
AU - Paiva, Sandra Vieira
AU - Gurgel, Anne Larisse
AU - Rossi, Sergio
AU - Soares, Marcelo de Oliveira
TI - Heatwaves and a decrease in turbidity drive coral bleaching in Atlantic marginal equatorial reefs
T2 - Frontiers in Marine Science
PY - 2023
SP - 1061488
VL - 10
DO - 10.3389/fmars.2023.1061488
AB - Tropical reefs can occur naturally under suboptimal environmental conditions, where few reef-building corals thrive. These unique reefs are especially important for understanding resistance to global warming, but they are understudied. We studied a coral bleaching event that occurred in turbid reefs (~ 19 m deep) in the equatorial southwestern Atlantic. Mass bleaching was observed in 91% of the Siderastrea stellata colonies in 2020, whereas only 7.7% of the colonies were bleached in 2019 and 10.9% in 2022. The year 2020 had the highest heat stress recorded in this century in this region according to the degree of heating weeks such as 17.6°C-week. In the first semester of 2020, the region also underwent three marine heatwaves (MHWs) above the average temperatures (1.3, 1.5, and 2.0°C). The lowest turbidity and wind speed matched long-lasting, repeated, and severe MHWs. These reef-building corals are dominant under moderate turbid waters and high sea temperature (26–29°C), however they are near the maximum tolerance limit. In this regard, these low-latitude reefs are warming twice as fast (0.2°C/decade) as other regions (e.g., Abrolhos and Coral Coast) (0.1 to 0.13°C/decade) in the South America reef system demonstrating that they cannot be considered climate-change refugia. These results suggest that even turbid marginal reefs and tolerant corals are highly susceptible to mass bleaching, especially when heatwaves and a decrease in turbidity occur simultaneously.
ER -
