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Reigel AM, Easson CG, Apprill A, Freeman CJ, Bartley MM, Fiore CL. Sponge-derived matter is assimilated by coral holobionts. Commun Biol 2024; 7:146. [PMID: 38308082 PMCID: PMC10837432 DOI: 10.1038/s42003-024-05836-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 01/19/2024] [Indexed: 02/04/2024] Open
Abstract
Coral reef biodiversity is maintained by a complex network of nutrient recycling among organisms. Sponges assimilate nutrients produced by other organisms like coral and algae, releasing them as particulate and dissolved matter, but to date, only a single trophic link between sponge-derived dissolved matter and a macroalgae has been identified. We sought to determine if sponge-coral nutrient exchange is reciprocal using a stable isotope 'pulse-chase' experiment to trace the uptake of 13C and 15N sponge-derived matter by the coral holobiont for three coral species (Acropora cervicornis, Orbicella faveolata, and Eunicea flexuosa). Coral holobionts incorporated 2.3-26.8x more 15N than 13C from sponge-derived matter and A. cervicornis incorporated more of both C and N than the other corals. Differential isotopic incorporation among coral species aligns with their ecophysiological characteristics (e.g., morphology, Symbiodiniaceae density). Our results elucidate a recycling pathway on coral reefs that has implications for improving coral aquaculture and management approaches.
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Affiliation(s)
| | - Cole G Easson
- Middle Tennessee State University, Murfreesboro, TN, USA
| | - Amy Apprill
- Woods Hole Oceanographic Institution, Woods Hole, RI, USA
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2
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Rey-Villiers N, Sánchez A, González-Díaz P, Álvarez-Filip L. Morphometric responses of two zooxanthellate octocorals along a water quality gradient in the Cuban northwestern coast. PLoS One 2023; 18:e0290293. [PMID: 37594931 PMCID: PMC10437867 DOI: 10.1371/journal.pone.0290293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Accepted: 08/04/2023] [Indexed: 08/20/2023] Open
Abstract
Octocoral abundance is increasing on Caribbean reefs, and one of the possible causes is their vertical morphological plasticity that allows them to grow above the substrate to reduce the effect of processes that occur in it (e.g., scour by sediments) as well as adapt to environmental gradients. The aim of this study was to determine the morphometric response of two octocorals species (Eunicea flexuosa and Plexaura kükenthali) with different life strategies in a water quality gradient. The research was carried out between 2008 and 2016 on eight forereefs of northwest Cuba. Different morphometric indicators were measured in the colonies of both species found within a belt transect (100 x 2 m) randomly located at each site. The lowest means in height, diameter, number of terminal branches/colony, cover index, and least arborescent colonies of E. flexuosa were detected at the sites with the greatest anthropogenic pollution. The water quality gradient did not explain the variability of the five morphometric indicators of P. kükenthali. However, hydrodynamic stress was the factor that most negatively affected the morphometry of this species. The chronic effect of poor water quality over time resulted in more small sized colonies of E. flexuosa at the polluted site, probably due to higher mortality. The size distribution of P. kükenthali also showed the same trend but at the sites with greater hydrodynamic stress. These results show that the morphometric response of octocorals along a water quality gradient is species-specific. This study suggests that poor water quality decreases the size and thus availability of habitat provided by octocorals sensitive to that factor (e.g., E. flexuosa) while other tolerant species (e.g., P. kükenthali) could provide the habitat of several organisms in a scenario of increasing anthropogenic pollution.
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Affiliation(s)
- Néstor Rey-Villiers
- Biodiversity and Reef Conservation Laboratory, Unidad Académica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos, Quintana Roo, México
| | - Alberto Sánchez
- Centro Interdisciplinario de Ciencias Marinas del Instituto Politécnico Nacional, La Paz, Baja California Sur, México
| | | | - Lorenzo Álvarez-Filip
- Biodiversity and Reef Conservation Laboratory, Unidad Académica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos, Quintana Roo, México
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3
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Bosch NE, Espino F, Tuya F, Haroun R, Bramanti L, Otero-Ferrer F. Black coral forests enhance taxonomic and functional distinctiveness of mesophotic fishes in an oceanic island: implications for biodiversity conservation. Sci Rep 2023; 13:4963. [PMID: 36973395 PMCID: PMC10043018 DOI: 10.1038/s41598-023-32138-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 03/23/2023] [Indexed: 03/29/2023] Open
Abstract
The degradation of shallow ecosystems has called for efforts to understand the biodiversity and functioning of Mesophotic Ecosystems. However, most empirical studies have been restricted to tropical regions and have majorly focused on taxonomic entities (i.e., species), neglecting important dimensions of biodiversity that influence community assembly and ecosystem functioning. Here, using a subtropical oceanic island in the eastern Atlantic Ocean (Lanzarote, Canary Islands), we investigated variation in (a) alpha and (b) beta functional (i.e., trait) diversity across a depth gradient (0-70 m), as a function of the presence of black coral forests (BCFs, order Antipatharian) in the mesophotic strata, a vulnerable but often overlooked 'ecosystem engineer' in regional biodiversity. Despite occupying a similar volume of the functional space (i.e., functional richness) than shallow (< 30 m) reefs, mesophotic fish assemblages inhabiting BCFs differed in their functional structure when accounting for species abundances, with lower evenness and divergence. Similarly, although mesophotic BCFs shared, on average, 90% of the functional entities with shallow reefs, the identity of common and dominant taxonomic and functional entities shifted. Our results suggest BCFs promoted the specialization of reef fishes, likely linked to convergence towards optimal traits to maximize the use of resources and space. Regional biodiversity planning should thus focus on developing specific management and conservation strategies for preserving the unique biodiversity and functionality of mesophotic BCFs.
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Affiliation(s)
- Nestor E Bosch
- Asociación Biodiversidad Atlántica y Sostenibilidad (ABAS), 35214, Telde, Spain.
- Grupo en Biodiversidad y Conservación (IU-ECOAQUA), Universidad de Las Palmas de Gran Canaria, 35214, Telde, Spain.
| | - Fernando Espino
- Grupo en Biodiversidad y Conservación (IU-ECOAQUA), Universidad de Las Palmas de Gran Canaria, 35214, Telde, Spain
| | - Fernando Tuya
- Grupo en Biodiversidad y Conservación (IU-ECOAQUA), Universidad de Las Palmas de Gran Canaria, 35214, Telde, Spain
| | - Ricardo Haroun
- Grupo en Biodiversidad y Conservación (IU-ECOAQUA), Universidad de Las Palmas de Gran Canaria, 35214, Telde, Spain
| | - Lorenzo Bramanti
- Sorbonne Université, CNRS, Laboratoire d'Ecogéochimie des Environnements Benthiques, LECOB, 66500, Banyuls-sur-Mer, France
| | - Francisco Otero-Ferrer
- Asociación Biodiversidad Atlántica y Sostenibilidad (ABAS), 35214, Telde, Spain
- Grupo en Biodiversidad y Conservación (IU-ECOAQUA), Universidad de Las Palmas de Gran Canaria, 35214, Telde, Spain
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4
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Zelli E, Simancas-Giraldo SM, Xiang N, Dessì C, Katzer ND, Tilstra A, Wild C. Individual and combined effect of organic eutrophication (DOC) and ocean warming on the ecophysiology of the Octocoral Pinnigorgia flava. PeerJ 2023; 11:e14812. [PMID: 36814959 PMCID: PMC9940650 DOI: 10.7717/peerj.14812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 01/06/2023] [Indexed: 02/19/2023] Open
Abstract
Dissolved organic carbon (DOC) enrichment and ocean warming both negatively affect hard corals, but studies on their combined effects on other reef organisms are scarce. Octocorals are likely to become key players in future reef communities, but they are still highly under-investigated with regard to their responses to global and local environmental changes. Thus, we evaluated the individual and combined effects of DOC enrichment (10, 20 and 40 mg L-1 DOC, added as glucose) and warming (stepwise from 26 to 32 °C) on the widespread Indo-Pacific gorgonian Pinnigorgia flava in a 45-day laboratory experiment. Oxygen fluxes (net photosynthesis and respiration), as well as Symbiodiniaceae cell density and coral growth were assessed. Our results highlight a differential ecophysiological response to DOC enrichment and warming as well as their combination. Individual DOC addition did not significantly affect oxygen fluxes nor Symbiodiniaceae cell density and growth, while warming significantly decreased photosynthesis rates and Symbiodiniaceae cell density. When DOC enrichment and warming were combined, no effect on P. flava oxygen fluxes was observed while growth responded to certain DOC conditions depending on the temperature. Our findings indicate that P. flava is insensitive to the individual effect of DOC enrichment, but not to warming and the two stressors combined. This suggests that, if temperature remains below certain thresholds, this gorgonian species may gain a competitive advantage over coral species that are reportedly more affected by DOC eutrophication. However, under the expected increasing temperature scenarios, it is also likely that this octocoral species will be negatively affected, with potential consequences on community structure. This study contributes to our understanding of the conditions that drive phase shift dynamics in coastal coral reef ecosystemds.
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Affiliation(s)
- Edoardo Zelli
- Marine Ecology Department, Faculty of Biology & Chemistry (FB 2), University of Bremen, Bremen, Germany,School of Science, University of Waikato, Tauranga, New Zealand
| | | | - Nan Xiang
- Marine Ecology Department, Faculty of Biology & Chemistry (FB 2), University of Bremen, Bremen, Germany,Helmholtz Centre for Polar and Marine Research, Alfred Wegener Institute, Bremerhaven, Germany
| | - Claudia Dessì
- Marine Ecology Department, Faculty of Biology & Chemistry (FB 2), University of Bremen, Bremen, Germany,Dipartimento di Scienze della Vita e dell’Ambiente, University of Cagliari, Cagliari, Italy
| | - Nadim Daniel Katzer
- Marine Ecology Department, Faculty of Biology & Chemistry (FB 2), University of Bremen, Bremen, Germany
| | - Arjen Tilstra
- Marine Ecology Department, Faculty of Biology & Chemistry (FB 2), University of Bremen, Bremen, Germany
| | - Christian Wild
- Marine Ecology Department, Faculty of Biology & Chemistry (FB 2), University of Bremen, Bremen, Germany
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5
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Lolis LA, Miranda RJ, Barros F. The effects of an invasive soft coral on the structure of native benthic communities. MARINE ENVIRONMENTAL RESEARCH 2023; 183:105802. [PMID: 36403410 DOI: 10.1016/j.marenvres.2022.105802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 10/28/2022] [Accepted: 11/01/2022] [Indexed: 06/16/2023]
Abstract
Species invasion is a major threat to marine biodiversity and function; thus, studying the effects of recently reported exotic species is extremely important. Several soft coral species (Alcyonacea) have invaded the Atlantic Ocean but their effects are poorly known. Here, we investigated the effects of the invasive species Sarcothelia sp. (Alcyonacea, Xeniidae) on native benthic shallow reef communities in Brazil. We hypothesized that increasing Sarcothelia sp. abundance would be related to species richness decreases and native community structure changes. Multivariate analysis showed significant dissimilarity between invaded (high Sarcothelia sp. abundance) and non-invaded areas (high abundance of the octocoral Neospongodes atlantica and zoantharians). The invaded area showed less species composition variability (i.e., homogenization) than non-invaded ones. Within the invaded area we observed that Sarcothelia sp. abundance reduced species richness. The lowest native benthic richness (10 taxa) was observed in a transect with the highest invader cover, while the transect with the lowest Sarcothelia sp. cover presented 26 native taxa. These findings are likely related to the invasive novel functional traits, i.e., invader growth form and allelochemicals. A clear inverse abundance pattern between invasive Sarcothelia sp. and N. atlantica, indicated an intense competition between octocorals. Our study showed remarkable evidence of negative impacts of invasive soft corals on reef biodiversity. There is an urgent need for experiments evaluating changes in different ecological processes and to implement management actions.
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Affiliation(s)
- Lucas Assumpção Lolis
- Laboratório de Ecologia Bentônica, CIENAM, Instituto de Biologia and INCT Estudos Interdisciplinares e Transdisciplinares em Ecologia e Evolução, Universidade Federal da Bahia, Salvador, Brazil. Rua Barão de Jeremoabo, s/n. Campus Ondina, 40170-115, Salvador, Bahia, Brazil.
| | - Ricardo J Miranda
- Laboratório de Biologia Marinha e Conservação, Instituto de Ciências Biológicas e da Saúde, Universidade Federal de Alagoas, Av. Lourival Melo Mota, s/n, Tabuleiro do Martins, CEP: 57072-900, Maceió, Alagoas, Brazil
| | - Francisco Barros
- Laboratório de Ecologia Bentônica, CIENAM, Instituto de Biologia and INCT Estudos Interdisciplinares e Transdisciplinares em Ecologia e Evolução, Universidade Federal da Bahia, Salvador, Brazil. Rua Barão de Jeremoabo, s/n. Campus Ondina, 40170-115, Salvador, Bahia, Brazil
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6
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Cordeiro RT, Carpinelli ÁN, Francini-Filho RB, Neves BDM, Pérez CD, de Oliveira U, Sumida P, Maranhão H, Monteiro LH, Carneiro P, Kitahara MV. Neospongodes atlantica, a potential case of an early biological introduction in the Southwestern Atlantic. PeerJ 2022; 10:e14347. [PMID: 36540794 PMCID: PMC9760029 DOI: 10.7717/peerj.14347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 10/16/2022] [Indexed: 12/23/2022] Open
Abstract
Soft corals (Anthozoa: Octocorallia) are discreet components in the Southwestern Atlantic reef communities. In Brazil, the native octocoral shallow-reef fauna is mostly represented by gorgonians. Consequently, except for the nephtheid Neospongodes atlantica, most of the known soft corals from this region are considered non-indigenous. Hitherto, the monotypic genus Neospongodes, which was proposed in the early 1900s, has been considered to be endemic to the Northeastern Brazilian coast. Herein, based on in situ records, we show that N. atlantica is a substrate generalist that has been probably expanding its distribution by dominating extensive shallow and mesophotic sandy and reef bottoms, generally outcompeting other reef benthic organisms, including Brazilian endemic species. Based on previously unidentified museum specimens, new records, and a broad literature review, we provide the most comprehensive modelling of the potential distribution of this species in the Southwestern Atlantic. Based on molecular inference supported by in-depth morphological analysis, the probable non-indigenous and, therefore, ancient introduction of N. atlantica in Brazilian waters is discussed. Finally, these results support that Neospongodes and the Indo-Pacific Stereonephthya are synonyms, which led us to propose the latter as taxonomically invalid.
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Affiliation(s)
- Ralf T.S. Cordeiro
- Departamento de Biologia, Universidade Federal Rural de Pernambuco, Recife, Pernambuco, Brazil,Department of Zoology (Invertebrate Zoology), National Museum of Natural History, Smithsonian Institution, Washington, D.C., United States of America
| | - Ágatha Nascimento Carpinelli
- Programa de Pós-graduação em Biodiversidade e Ecologia Marinha e Costeira, Universidade Federal de São Paulo, Santos, São Paulo, Brazil
| | | | | | - Carlos D. Pérez
- Centro Acadêmico de Vitória, Universidade Federal de Pernambuco, Vitória de Santo Antão, Pernambuco, Brazil
| | - Umberto de Oliveira
- Programa de Pós-Graduação em Ecologia, Teoria, Aplicações e Valores, Universidade Federal da Bahia, Salvador, Bahia, Brazil
| | - Paulo Sumida
- Departamento de Oceanografia Biológica, Instituto Oceanográfico, Universidade de São Paulo, São Paulo, Brazil
| | - Henrique Maranhão
- Programa de Pós-Graduação em Oceanografia, Departamento de Oceanografia, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil
| | - Leonardo H.U. Monteiro
- IVIG, COPPE, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil,Grupo Sandmine & Inframar, Fortaleza, Ceará, Brazil
| | - Pedro Carneiro
- Universidade Federal do Delta do Paranaíba, Parnaíba, Piauí, Brazil
| | - Marcelo V. Kitahara
- Department of Zoology (Invertebrate Zoology), National Museum of Natural History, Smithsonian Institution, Washington, D.C., United States of America,Centro de Biologia Marinha, Universidade de São Paulo, São Sebastião, São Paulo, Brazil
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7
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Bell JJ, Shaffer M, Luter HM, Mana R, Rodolfo-Metalpa R. Phototrophic sponge productivity may not be enhanced in a high CO 2 world. GLOBAL CHANGE BIOLOGY 2022; 28:4900-4911. [PMID: 35662355 DOI: 10.1111/gcb.16235] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 04/28/2022] [Accepted: 05/03/2022] [Indexed: 06/15/2023]
Abstract
Sponges are major components of benthic communities across the world and have been identified as potential "winners" on coral reefs in the face of global climate change as result of their tolerance to ocean warming and acidification (OA). Previous studies have also hypothesised that photosymbiont-containing sponges might have higher productivity under future OA conditions as a result of photosymbionts having increased access to CO2 and subsequently greater carbon production. Here we test this hypothesis for a widespread and abundant photosymbiont-containing sponge species Lamellodysidea herbacea at a CO2 seep in Papua New Guinea simulating OA conditions. We found seep sponges had relatively higher cyanobacterial abundance, chlorophyll concentrations and symbiont photosynthetic efficiency than non-seep sponges, and a three-fold higher sponge abundance at the seep site. However, while gross oxygen production was the same for seep and non-seep sponges, seep sponge dark respiration rates were higher and instantaneous photosynthesis: respiration (P:R) ratios were lower. We show that while photosymbiont containing sponges may not have increased productivity under OA, they are able to show flexibility in their relationships with microbes and offset increased metabolic costs associated with climate change associated stress.
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Affiliation(s)
- James J Bell
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Megan Shaffer
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Heidi M Luter
- Australian Institute of Marine Science, Townsville, Queensland, Australia
| | - Ralph Mana
- School of Natural and Physical Sciences, University of Papua New Guinea, Port Moresby, Papua New Guinea
| | - Riccardo Rodolfo-Metalpa
- ENTROPIE, IRD, Université de la Réunion, CNRS, IFREMER, Université de Nouvelle-Calédonie, Nouméa, New Caledonia
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8
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Soares MO, Kitahara MV, Santos MEA, Bejarano S, Rabelo EF, Cruz ICS. The flourishing and vulnerabilities of zoantharians on Southwestern Atlantic reefs. MARINE ENVIRONMENTAL RESEARCH 2022; 173:105535. [PMID: 34879290 DOI: 10.1016/j.marenvres.2021.105535] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 11/18/2021] [Accepted: 11/21/2021] [Indexed: 06/13/2023]
Abstract
In the Southwestern Atlantic reefs (SWA), some species of massive scleractinians and zoantharians are adapted to turbid waters, periodic desiccation, and sediment resuspension events. Moreover, phase shifts in this region have mostly been characterized by the emergence of algae and, less typically, zoantharians. However, nutrient excess and organic pollution are key drivers of the hard coral habitat degradation and may, thus, favor the emergence of novel zoantharian-dominated habitats. Many zoantharian species, particularly those from the genera Palythoa and Zoanthus, have traits that could help them thrive under conditions detrimental to reef-building corals, including rapid growth, several asexual reproduction strategies, high morphological plasticity, and generalist nutrient acquisition strategies. Thus, in a near future, stress-tolerant zoantharians may thrive in nutrient-enriched subtidal SWA locations under low heat stress, such as, upwelling. Overall, coral-zoantharian phase shifts in the SWA may decrease the species richness of reef communities, ultimately influencing ecosystem functioning and services, such as the provision of nursery habitats, fish biomass production, and coastline protection. However, zoantharians will also be threatened at intertidal zones, which are expected to experience higher heat stress, solar radiation, and sea-level rise. Although zoantharians appear to cope well with some local stressors (e.g., decreasing water quality), they are vulnerable to climate change (e.g., heatwaves), invasive species (Tubastraea spp.), microplastics, diseases, and mostly restricted to a narrow depth range (0-15 m depth) in SWA reefs. This shallow zone is particularly affected by climate change, compressing the three-dimensional habitat and limiting depth refugia in deeper SWA reefs. As mesophotic ecosystems have been hypothesized as short-term refuges to disturbances for some species, the narrow depth limit of zoantharians seems to be a potential factor that might increase their vulnerability to growing climate change pressures in SWA shallow-water reefs. Together, these could lead to both range expansions in some locations and loss of suitable reef habitats in other sites. Additional research is needed to better understand the systemic responses of these novel SWA reefs to the concert of increasing and interactive local and global stressors, and their implications for ecosystem functioning and service provisions.
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Affiliation(s)
- Marcelo Oliveira Soares
- Instituto de Ciências do Mar (LABOMAR), Universidade Federal do Ceará (UFC), Fortaleza, Brazil.
| | | | | | - Sonia Bejarano
- Reef Systems Research Group, Leibniz Center for Tropical Marine Research (ZMT), Bremen, Germany
| | | | - Igor Cristino Silva Cruz
- Departamento de Oceanografia, Instituto de Geociências, Universidade Federal da Bahia (UFBA), Salvador, Brazil
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9
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Regime shifts on tropical coral reef ecosystems: future trajectories to animal-dominated states in response to anthropogenic stressors. Emerg Top Life Sci 2021; 6:95-106. [PMID: 34927689 DOI: 10.1042/etls20210231] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 11/22/2021] [Accepted: 11/25/2021] [Indexed: 02/01/2023]
Abstract
Despite the global focus on the occurrence of regime shifts on shallow-water tropical coral reefs over the last two decades, most of this research continues to focus on changes to algal-dominated states. Here, we review recent reports (in approximately the last decade) of regime shifts to states dominated by animal groups other than zooxanthellate Scleractinian corals. We found that while there have been new reports of regime shifts to reefs dominated by Ascidacea, Porifera, Octocorallia, Zoantharia, Actiniaria and azooxanthellate Scleractinian corals, some of these changes occurred many decades ago, but have only just been reported in the literature. In most cases, these reports are over small to medium spatial scales (<4 × 104 m2 and 4 × 104 to 2 × 106 m2, respectively). Importantly, from the few studies where we were able to collect information on the persistence of the regime shifts, we determined that these non-scleractinian states are generally unstable, with further changes since the original regime shift. However, these changes were not generally back to coral dominance. While there has been some research to understand how sponge- and octocoral-dominated systems may function, there is still limited information on what ecosystem services have been disrupted or lost as a result of these shifts. Given that many coral reefs across the world are on the edge of tipping points due to increasing anthropogenic stress, we urgently need to understand the consequences of non-algal coral reef regime shifts.
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10
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Reverter M, Jackson M, Rohde S, Moeller M, Bara R, Lasut MT, Segre Reinach M, Schupp PJ. High taxonomic resolution surveys and trait-based analyses reveal multiple benthic regimes in North Sulawesi (Indonesia). Sci Rep 2021; 11:16554. [PMID: 34400684 PMCID: PMC8367970 DOI: 10.1038/s41598-021-95905-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 07/29/2021] [Indexed: 02/07/2023] Open
Abstract
As coral reef communities change and reorganise in response to increasing disturbances, there is a growing need for understanding species regimes and their contribution to ecosystem processes. Using a case study on coral reefs at the epicentre of tropical marine biodiversity (North Sulawesi, Indonesia), 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 communities. Our results show that using major categories fails to identify distinct coral reef regimes. We also show that monitoring of only scleractinian coral communities is insufficient to detect different benthic regimes, especially communities dominated by non-coral organisms, and that all types of benthic organisms need to be considered. We have implemented 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. 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.
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Affiliation(s)
- Miriam Reverter
- Institute for Chemistry and Biology of the Marine Environment (ICBM) at the Carl Von Ossietzky University of Oldenburg, Wilhelmshaven, Germany.
| | - Matthew Jackson
- Institute for Chemistry and Biology of the Marine Environment (ICBM) at the Carl Von Ossietzky University of Oldenburg, Wilhelmshaven, Germany
| | - Sven Rohde
- Institute for Chemistry and Biology of the Marine Environment (ICBM) at the Carl Von Ossietzky University of Oldenburg, Wilhelmshaven, Germany
| | - Mareen Moeller
- Institute for Chemistry and Biology of the Marine Environment (ICBM) at the Carl Von Ossietzky University of Oldenburg, Wilhelmshaven, Germany
| | - Robert Bara
- Faculty of Fisheries and Marine Science, Sam Ratulangi University, Jl. Kampus UNSRAT Bahu, 95115, Manado, Sulawesi Utara, Indonesia
| | - Markus T Lasut
- Faculty of Fisheries and Marine Science, Sam Ratulangi University, Jl. Kampus UNSRAT Bahu, 95115, Manado, Sulawesi Utara, Indonesia
| | | | - Peter J Schupp
- Institute for Chemistry and Biology of the Marine Environment (ICBM) at the Carl Von Ossietzky University of Oldenburg, Wilhelmshaven, Germany
- Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB), 26129, Oldenburg, Germany
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11
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Simancas-Giraldo SM, Xiang N, Kennedy MM, Nafeh R, Zelli E, Wild C. Photosynthesis and respiration of the soft coral Xenia umbellata respond to warming but not to organic carbon eutrophication. PeerJ 2021; 9:e11663. [PMID: 34395065 PMCID: PMC8323596 DOI: 10.7717/peerj.11663] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 06/01/2021] [Indexed: 11/20/2022] Open
Abstract
Eutrophication with dissolved organic carbon (DOC) as a far under-investigated stressor, and ocean warming, can strongly affect coral reefs and hard corals as major reefs ecosystem engineers. However, no previous studies have investigated the metabolic responses of soft corals to DOC eutrophication, or its interaction with ocean warming. Thus, we investigated respiration and photosynthesis response of Xenia umbellata, a common mixotrophic soft coral from the Indo-pacific, to (1) three levels of DOC eutrophication simulated by glucose addition over the first 21 days of experiment and (2) ocean warming scenarios where the temperature was gradually increased from 26 °C (control condition) to 32 °C over another 24 days in an aquarium experiment. We found no significant difference in response to DOC treatments and all corals survived regardless of the DOC concentrations, whilst subsequent exposure to simulated ocean warming significantly decreased gross photosynthesis by approximately 50% at 30 °C, and 65% at 32 °C, net photosynthesis by 75% at 30 °C and 79% at 32 °C, and respiration by a maximum of 75% at 30 °C; with a slight increase at 32 °C of 25%. The ratio between gross photosynthesis and respiration decreased by the end of the warming period but remained similar between controls and colonies previously exposed to DOC. Our findings suggest that soft corals may be more resistant than hard corals to DOC eutrophication and in consequence, may potentially experiment in less magnitude the negative effects of increased temperature or subsequently both stressors. The results of this study may contribute to explain the successful role of soft corals in phase shifts as reported from many coral reefs. Where predicted declines in reef ecosystems health due to increased eutrophication levels can be exacerbated by future warming.
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Affiliation(s)
| | - Nan Xiang
- Marine Ecology Department, Universität Bremen, Bremen, Germany
- Helmholtz Centre for Polar and Marine Research, Alfred Wegener Institute, Bremerhaven, Germany
| | | | - Rassil Nafeh
- Marine Ecology Department, Universität Bremen, Bremen, Germany
| | - Edoardo Zelli
- Marine Ecology Department, Universität Bremen, Bremen, Germany
- Dipartimento di Scienze Biologiche, Geologiche ed Ambientali (BiGeA) & Centro Interdipartimentale di Ricerca per le Scienze Ambientali (CIRSA), University of Bologna, Italy
| | - Christian Wild
- Marine Ecology Department, Universität Bremen, Bremen, Germany
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Edmunds PJ. High ecological resilience of the sea fan Gorgonia ventalina during two severe hurricanes. PeerJ 2020; 8:e10315. [PMID: 33240641 PMCID: PMC7666550 DOI: 10.7717/peerj.10315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 10/16/2020] [Indexed: 11/20/2022] Open
Abstract
Since about the turn of the millennium, octocorals have been increasing in abundance on Caribbean reefs. The mechanisms underlying this trend have not been resolved, but the emergent species assemblage appears to be more resilient than the scleractinians they are replacing. The sea fan Gorgonia ventalina is an iconic species in the contemporary octocoral fauna, and here its population dynamics are described from St. John, US Virgin Islands, from 2013 to 2019. Mean densities of G. ventalina at Yawzi Point (9-m depth) varied from 1.4-1.5 colonies m-2, and their mean heights from 24-30 cm; nearby at Tektite (14-m depth), they varied from 0.6-0.8 colonies m-2 and from 25-33 cm. These reefs were impacted by two Category 5 hurricanes in 2017, but neither the density of G. ventalina, the density of their recruits (< 5-cm tall), nor the height of colonies, differed among years, although growth was depressed after the hurricanes. Nevertheless, at Tektite, colony height trended upwards over time, in part because colonies 10.1-20 cm tall were reduced in abundance after the hurricanes. These trends were sustained without density-associated effects mediating recruitment or self-thinning of adults. The dynamics of G. ventalina over seven years reveals the high resilience of this species that will contribute to the persistence of octocorals as a dominant state on Caribbean reefs.
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Affiliation(s)
- Peter J. Edmunds
- Department of Biology, California State University, Northridge, CA, United States of America
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