scholarly journals Four-year monthly sediment deposition on turbid southwestern Atlantic coral reefs, with a comparison of benthic assemblages

2012 ◽  
Vol 60 (1) ◽  
pp. 49-63 ◽  
Author(s):  
Clovis Barreira e Castro ◽  
Bárbara Segal ◽  
Fábio Negrão ◽  
Emiliano Nicolas Calderon
Keyword(s):  
Coral Reef ◽  
Coral Reefs ◽  
Benthic Communities ◽  
Sediment Deposition ◽  
Southwestern Atlantic ◽  
Benthic Assemblages ◽  
Deposition Rates ◽  
Reef Communities ◽  
High Sedimentation ◽  
Coral Reef Communities

High sedimentation is often related to stress in coral reef communities. Most southwestern Atlantic reefs are characterized by high sedimentation. However, there are no temporal series of sediment deposition rates. We evaluated sediment deposition, the sediment carbonate composition and coral and zoanthid covers on six reefs in Brazil over four-years. Sediment deposition rates varied from near zero to 233 mg cm-2 day-1, with peaks between August and December, and yearly averages ranging from nine to 104 mg cm-2 day-1. Deposition rates presented site-specific correlations with wind, indicating that resuspension must be a major factor. The presence of carbonates varied from 38% to 90%, with two sites showing seasonal differences. Benthic communities were fairly similar among sites, but the analyses suggested particular frequencies at each site. There was no significant correlation between sediment and benthic communities. However, Palythoa caribaeorum usually occur in high sediment deposition areas. Our results did not corroborate previous data that suggested that a 10 mg cm-2 day-1 would be a "critical limit for coral survival". Some coral reefs may be associated with high sedimentation environments including carbonatic fractions, but which does not per se hinder the development of southwestern Atlantic coral reef communities.

scholarly journals Ocean acidification accelerates dissolution of experimental coral reef communities

2015 ◽  
Vol 12 (2) ◽  
pp. 365-372 ◽  
Author(s):  
S. Comeau ◽  
R. C. Carpenter ◽  
C. A. Lantz ◽  
P. J. Edmunds
Keyword(s):  
Coral Reef ◽  
Ocean Acidification ◽  
Benthic Communities ◽  
French Polynesia ◽  
High Pco2 ◽  
Back Reef ◽  
Percentage Cover ◽  
Tropical Coral ◽  
Reef Communities ◽  
Coral Reef Communities

Abstract. Ocean acidification (OA) poses a severe threat to tropical coral reefs, yet much of what is know about these effects comes from individual corals and algae incubated in isolation under high pCO2. Studies of similar effects on coral reef communities are scarce. To investigate the response of coral reef communities to OA, we used large outdoor flumes in which communities composed of calcified algae, corals, and sediment were combined to match the percentage cover of benthic communities in the shallow back reef of Moorea, French Polynesia. Reef communities in the flumes were exposed to ambient (~ 400 μatm) and high pCO2 (~ 1300 μatm) for 8 weeks, and calcification rates measured for the constructed communities including the sediments. Community calcification was reduced by 59% under high pCO2, with sediment dissolution explaining ~ 50% of this decrease; net calcification of corals and calcified algae remained positive but was reduced by 29% under elevated pCO2. These results show that, despite the capacity of coral reef calcifiers to maintain positive net accretion of calcium carbonate under OA conditions, reef communities might transition to net dissolution as pCO2 increases, particularly at night, due to enhanced sediment dissolution.

Noise pollution on coral reefs? — A yet underestimated threat to coral reef communities

2021 ◽  
Vol 165 ◽  
pp. 112129
Author(s):  
Christine Ferrier-Pagès ◽  
Miguel C. Leal ◽  
Ricardo Calado ◽  
Dominik W. Schmid ◽  
Frédéric Bertucci ◽  
...  
Keyword(s):  
Coral Reef ◽  
Coral Reefs ◽  
Noise Pollution ◽  
Reef Communities ◽  
Coral Reef Communities

scholarly journals Beyond coral-algal regimes: high taxonomic resolution surveys and trait-based analyses reveal multiple benthic regimes

2021 ◽  
Author(s):  
Miriam Reverter ◽  
Matthew Jackson ◽  
Sven Rohde ◽  
Mareen Moeller ◽  
Robert Bara ◽  
...  
Keyword(s):  
Coral Reef ◽  
Taxonomic Resolution ◽  
Marine Biodiversity ◽  
Soft Corals ◽  
Benthic Assemblages ◽  
North Sulawesi ◽  
Reef Communities ◽  
Coral Communities ◽  
Specific Species ◽  
Coral Reef Communities

As coral reef communities change and reorganise in response to anthropogenic and climate disturbances, there is a growing need of detecting and understanding the different emerging species regimes and their contribution to key ecosystem processes. Using a case study on coral reefs at the epicentre of tropical marine biodiversity (North Sulawesi), we explored how application of different biodiversity approaches (i.e. use of major taxonomic categories, high taxonomic resolution categories and trait-based approaches) affects the detection of distinct fish and benthic community assemblages. Our results show that using major categories (family level or above) to study coral reef communities fails to identify distinct regimes. We also show that for detection of different benthic regimes, especially communities dominated by non-coral organisms, monitoring of only scleractinian coral communities is insufficient, and that all types of benthic organisms (e.g. sponges, ascidians, soft corals, algae etc.) need to be considered. We have implemented for the first time, the use of a trait-based approach to study the functional diversity of whole coral reef benthic assemblages, which allowed us to detect five different community regimes, only one of which was dominated by scleractinian corals. We circumvented the challenge that for some benthic groups (e.g. sponges, ascidians or some soft corals) visual identification up to the species level is not possible, by identifying and categorising traits that can be applied to groups of similar organisms instead of specific species. Furthermore, by the parallel study of benthic and fish communities we provide new insights into key processes and functions that might dominate or be compromised in the different community regimes.

scholarly journals Ocean acidification accelerates dissolution of experimental coral reef communities

2014 ◽  
Vol 11 (8) ◽  
pp. 12323-12339 ◽  
Author(s):  
S. Comeau ◽  
R. C. Carpenter ◽  
C. A. Lantz ◽  
P. J. Edmunds
Keyword(s):  
Coral Reef ◽  
Ocean Acidification ◽  
Benthic Communities ◽  
French Polynesia ◽  
High Pco2 ◽  
Back Reef ◽  
Percentage Cover ◽  
Tropical Coral ◽  
Reef Communities ◽  
Coral Reef Communities

Abstract. Ocean acidification (OA) poses a severe threat to tropical coral reefs, yet much of what is know about these effects comes from individual corals and algae incubated in isolation under high pCO2. Studies of similar effects on coral reef communities are scarce. To investigate the response of coral reef communities to OA, we used large outdoor flumes in which communities composed of calcified algae, corals, and sediment were combined to match the percentage cover of benthic communities in the shallow back reef of Moorea, French Polynesia. Reef communities in the flumes were exposed to ambient (~400 μatm) and high pCO2 (~1300 μatm) for 8 weeks, and calcification rates measured for the constructed communities including the sediments. Community calcification was depressed 59% under high pCO2, with sediment dissolution explaining ~50% of this decrease; net calcification of corals and calcified algae remained positive, but was reduced 29% under elevated pCO2. These results show that despite the capacity of coral reef calcifiers to maintain positive net accretion of calcium carbonate under OA conditions, reef communities might switch to net dissolution as pCO2 increases, particularly at night, due to enhanced sediment dissolution.

Dimethylated sulfur compounds in coral-reef ecosystems

2016 ◽  
Vol 13 (2) ◽  
pp. 239 ◽  
Author(s):  
Elisabeth Deschaseaux ◽  
Graham Jones ◽  
Hilton Swan
Keyword(s):  
Climate Change ◽  
Coral Reef ◽  
Coral Reefs ◽  
Sulfur Compounds ◽  
Future Climate ◽  
Future Climate Change ◽  
Climate Change Scenarios ◽  
Reef Communities ◽  
Coral Reef Ecosystems ◽  
Coral Reef Communities

Environmental contextDimethylated sulfur compounds can exert multiple biological and environmental effects including climate regulation. Climate change and other anthropogenic factors are predicted to affect coral-reef ecosystems where these sulfur compounds are particularly abundant. We review the processes that regulate the production of dimethylated sulfur compounds in coral reefs and the potential consequences of environmental changes on their biogenic cycle in such fragile ecosystems under future climate change scenarios. AbstractDimethylsulfoniopropionate (DMSP) and its main breakdown products dimethylsulfide (DMS) and dimethylsulfoxide (DMSO) are biogenic species in the marine environment. In coral reefs, these dimethylated sulfur compounds (DSCs) have been reported at greater concentrations than in other marine ecosystems, which is most likely attributable to the extraordinary large biodiversity of coral reef communities (e.g. corals, macroalgae, coralline algae, invertebrates) and to the unique ability of zooxanthellate corals to synthesise DMSP from both the animal host and algal symbionts. Besides the various biological functions that have been attributed to DSCs, including thermoregulation, osmoregulation, chemoattraction and antioxidant response, DMS is suspected to take part in a climate feedback loop that could help counteract global warming. Nowadays, anthropogenic effects such as pollution, overfishing, increased sedimentation and global climate change are imminently threatening the health of coral reef communities around the world, with possible consequences on the natural cycle of DSCs within these ecosystems. This review provides insight into the biogeochemistry of DSCs in coral reefs and discusses the implications of projected changes in DSC production in these increasingly stressed ecosystems under future climate change scenarios. It shows that DSC dynamics will incontestably be affected in the near future, with possible feedback consequences on local climate.

North-south gradient of incidence, distribution and variations of coral reef communities in the Andaman and Nicobar Islands, India

2017 ◽  
Vol 21 (2) ◽  
pp. 289-301 ◽  
Author(s):  
N. Marimuthu ◽  
J. S. Yogesh Kumar ◽  
C. Raghunathan ◽  
N. V. Vinithkumar ◽  
R. Kirubagaran ◽  
...  
Keyword(s):  
Coral Reef ◽  
Andaman And Nicobar Islands ◽  
Reef Communities ◽  
Nicobar Islands ◽  
Coral Reef Communities

Detection of changes in coral reef communities using Landsat-5 TM and Landsat-7 ETM+ data

2003 ◽  
Vol 29 (2) ◽  
pp. 201-209 ◽  
Author(s):  
David Palandro ◽  
Serge Andréfouët ◽  
Frank E Muller-Karger ◽  
Phillip Dustan ◽  
Chuanmin Hu ◽  
...  
Keyword(s):  
Coral Reef ◽  
Reef Communities ◽  
Landsat 7 ◽  
Landsat 5 Tm ◽  
Coral Reef Communities

scholarly journals Experimental reef communities persist under future ocean acidification and warming

2021 ◽  
Author(s):  
Christopher Jury ◽  
Keisha Bahr ◽  
Evan Barba ◽  
Russell Brainard ◽  
Annick Cros ◽  
...  
Keyword(s):  
Experimental Study ◽  
Species Richness ◽  
Coral Reef ◽  
Coral Reefs ◽  
Ocean Acidification ◽  
Community Composition ◽  
Functional State ◽  
Reef Communities ◽  
Paris Climate Agreement

Abstract Coral reefs are among the most sensitive ecosystems affected by ocean acidification and warming, and are predicted to shift from net accreting calcifier-dominated systems to net eroding algal-dominated systems over the coming decades. Here we present a long-term experimental study examining the responses of entire mesocosm coral reef communities to acidification (-0.2 pH units), warming (+ 2°C), and combined future ocean (-0.2 pH, + 2°C) treatments. We show that under future ocean conditions, net calcification rates declined yet remained positive, corals showed reduced abundance yet were not extirpated, and community composition shifted while species richness was maintained. Our results suggest that under Paris Climate Agreement targets, coral reefs could persist in an altered functional state rather than collapse.

Sign in / Sign up

Export Citation Format

Share Document