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1.
Rev. biol. trop ; Rev. biol. trop;71abr. 2023.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1449495

RESUMO

Introduction: The 1997-98 El Niño event caused massive coral bleaching and mortality in the Central Mexican Pacific (CMP). Punta de Mita alone used to harbor more than 30 % of the coral coverage in this region, with a mono-specific Pocillopora coverage. The 1997-1998 ENSO event caused massive coral mortality reducing live coral coverage to < 5 %. Despite being considered a coral region unlikely to recover, recent restoration efforts have been implemented to rehabilitate the coral community. Objective: To assess coral recovery by analyzing the coral growth and survival rates of branching Pocillopora species at Punta de Mita. Methods: Healthy coral fragments of opportunity were re-attached to the natural substrata using zip ties and measured considering their growth in terms of maximum length and width (cm) to determine their annual extension rates. Results: After 50 weeks, corals duplicated their size, with a mean growth of ~ 4 cm year-1. After 100 weeks (2 years), corals triplicated their size, increasing on average 8-9 cm in each diameter. Conclusions: Successful coral reef restoration activities in the Central Mexican Pacific are the result of Pocillopora's physiological processes, such as fast growth rates, and recent life-history traits, like the ability to cope with thermal anomalies, which enable them to thrive in a dynamic region severely affected by natural and anthropogenic perturbations. Indeed, a region considered unlikely to recover has regained its live coral cover from < 5 % in 1998 up to 15 % in 20 years. This demonstrates the importance of assisting natural coral recovery with restoration efforts, especially in coral locations that, despite environmental perturbations, have proven to be resilient and may become coral refugia areas under the current climate change scenario.


Introducción: El evento El Niño de 1997-98 causó un blanqueamiento y mortalidad masiva de corales en el Pacífico Central Mexicano (CMP). Solo Punta de Mita albergaba más del 30 % de la cobertura coralina de esta región, con una cobertura monoespecífica de Pocillopora. El evento ENSO de 1997-1998 causó una mortalidad masiva de corales que redujo la cobertura de corales vivos a < 5 %. A pesar de ser considerada una región de coral con pocas probabilidades de recuperarse, se han implementado esfuerzos de restauración recientes para rehabilitar la comunidad coralina. Objetivo: Evaluar la recuperación de coral analizando el crecimiento coralino y las tasas de supervivencia de especies ramificadas de Pocillopora en Punta de Mita. Métodos: Fragmentos de oportunidad de coral sanos se volvieron a unir a los sustratos naturales usando bridas y se midieron considerando su crecimiento en términos de longitud y ancho máximos (cm) para determinar sus tasas de extensión anual. Resultados : Después de 50 semanas, los corales duplicaron su tamaño, con un crecimiento promedio de ~ 4 cm año-1. Después de 100 semanas (2 años), los corales triplicaron su tamaño, aumentando en promedio 8-9 cm en cada diámetro. Conclusiones: Las actividades exitosas de restauración de arrecifes de coral en el Pacífico Central Mexicano son el resultado de los procesos fisiológicos de Pocillopora, tales como tasas de crecimiento rápido, y rasgos de historia de vida reciente, como la capacidad de hacer frente a anomalías térmicas, que les permiten prosperar en una región dinámica severamente afectada por perturbaciones naturales y antropogénicas. De hecho, esta región que se consideraba poco probable que se recuperara, ha recuperado su cobertura de coral vivo de < 5 % en 1998 hasta 15 % en 20 años. Esto demuestra la importancia de ayudar a la recuperación natural de los corales con los esfuerzos de restauración, especialmente en las ubicaciones de corales que, a pesar de las perturbaciones ambientales, han demostrado ser resistentes y pueden convertirse en áreas de refugio de corales ante el escenario actual de cambio climático.

2.
Sci Total Environ ; 807(Pt 2): 150880, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34634342

RESUMO

In November 2015, the collapse of the Fundão dam (Minas Gerais, Brazil) carried over 40 × 106 m3 of iron ore tailings into the Doce river and caused massive environmental and socioeconomic impacts across the watershed. The downstream mudslide scavenged contaminants deposited in the riverbed, and several potentially toxic elements were further released through reduction and solubilization of Fe oxy-hydroxides under estuarine conditions. A turbidity plume was formed off the river mouth, but the detection of contaminants' dispersion in the ocean remains poorly assessed. This situation is specially concerning because Southwestern Atlantic's largest and richest reefs are located 70-250 km to the north of the Doce river mouth, and the legal dispute over the extent of monitoring, compensation and restoration measures are based either on indirect evidence from modeling or on direct evidence from remote sensing and contaminated organisms. Coral skeletons can incorporate trace elements and are considered good monitors of marine pollution, including inputs from open cut mining. Here, we studied a Montastraea cavernosa (Linnaeus 1767) coral colony collected 220 km northward to the river mouth, using X-rays for assessing growth bands and Laser Ablation Inductively Coupled Plasma Mass Spectrometry to recover trace elements incorporated in growth bands formed between 2014 and 2018. A threefold positive Fe anomaly was identified in early 2016, associated with negative anomalies in several elements. Variation in Ba and Y was coherent with the region's sedimentation dynamics, but also increased after 2016, akin to Pb, V and Zn. Coral growth rates decreased after the disaster. Besides validating M. cavernosa as a reliable archive of ocean chemistry, our results evidence wide-reaching sub-lethal coral contamination in the Abrolhos reefs, as well as different incorporation mechanisms into corals' skeletons.


Assuntos
Antozoários , Colapso Estrutural , Oligoelementos , Animais , Monitoramento Ambiental , Rios
3.
J Exp Zool B Mol Dev Evol ; 336(3): 281-292, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33503321

RESUMO

The regenerative capacity of cnidarians plays an essential role in the maintenance and restoration of coral reef ecosystems by allowing faster recovery from disturbances and more efficient small-scale dispersal. However, in the case of invasive species, this property may contribute to their dispersal and success in nonnative habitats. Given that four Indo-Pacific members of the coral genus Tubastraea have invaded the Atlantic, here we evaluated the ability of three of these species (Tubastraea coccinea, Tubastraea diaphana, and Tubastraea micranthus) to regenerate from fragments of undifferentiated coral tissue to fully functional polyps in response to differences in food supply and fragment size. For comparative purposes, another colonial dendrophylliid (Dendrophyllia sp.) was included in the analyses. All dendrophylliids displayed regenerative ability and high survival rates that were independent of whether or not food was supplied or fragment size. However, regeneration rates varied between species and were influenced by fragment size. Temporal expression of key genes of the regenerative process (Wnt and FGF) was profiled during whole-body regeneration of T. coccinea, suggesting a remarkable regenerative ability of T. coccinea that points to its potential use as a laboratory model for the investigation of regeneration in colonial calcified anthozoans.


Assuntos
Antozoários/crescimento & desenvolvimento , Regeneração , Animais , Antozoários/genética , Espécies Introduzidas , Transdução de Sinais , Transcriptoma
4.
Sci Total Environ ; 742: 140562, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32721728

RESUMO

Framework-forming scleractinian (FFS) corals provide structurally complex habitats to support abundant and diverse benthic communities but are vulnerable to environmental changes and anthropogenic disturbances. Scientific modeling of suitable habitat provides important insights into the impact of the environmental conditions and fills the gap in the knowledge on habitat suitability. This study presents predictive habitat suitability modeling for deep-sea (depth > 50 m) FFS corals in the GoM. We first conducted a nonparametric estimate of the observed coral point process intensity as a function of each numeric environmental variable. Next, we performed species distribution modeling (SDM) using an assemble of four machine learning models - maximum entropy (ME), support vector machine (SVM), random forest (RF), and deep neural network (DNN). We found that most important variables controlling the coral distribution are super-dominant gravel and rock substrata, SW and SE aspects, slope steepness, salinity, depth, temperature, acidity, dissolved oxygen, and chlorophyll-a. Highly suitable habitats are predicted to be on the continental slope off Texas, Louisiana, and Mississippi and the shelf and slope of the West Florida Escarpment. All the four models have outstanding prediction performances with AUC values over 0.95. DNN model performs best (AUC = 0.987). The study contributes to coral habitat modeling research by presenting unique methods including nonparametric function of coral point process intensity, DNN and SVM models that have not been used in coral SDM, post-classification model assembling, and percentile approach to determine a threshold value for classifying a suitability score map into a binary map. Our findings would help support conservation prioritization, management and planning, and guide new field exploration.


Assuntos
Antozoários , Animais , Ecossistema , Florida , Golfo do México , Louisiana , Mississippi , Texas
5.
R Soc Open Sci ; 4(5): 170253, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28573035

RESUMO

Symbiodinium are responsible for the majority of primary production in coral reefs and found in a mutualistic symbiosis with multiple animal phyla. However, little is known about the molecular signals involved in the establishment of this symbiosis and whether it initiates during host larval development. To address this question, we monitored the expression of a putative symbiosis-specific gene (H+-ATPase) in Symbiodinium A1 ex hospite and in association with larvae of a scleractinian coral (Mussismilia hispida), a nudibranch (Berghia stephanieae) and a giant clam (Tridacna crocea). We acquired broodstock for each host, induced spawning and cultured the larvae. Symbiodinium cells were offered and larval samples taken for each host during the first 72 h after symbiont addition. In addition, control samples including free-living Symbiodinium and broodstock tissue containing symbionts for each host were collected. RNA extraction and RT-PCR were performed and amplified products cloned and sequenced. Our results show that H+-ATPase was expressed in Symbiodinium associated with coral and giant clam larvae, but not with nudibranch larvae, which digested the symbionts. Broodstock tissue for coral and giant clam also expressed H+-ATPase, but not the nudibranch tissue sample. Our results of the expression of H+-ATPase as a marker gene suggest that symbiosis between Symbiodinium and M. hispida and T. crocea is established during host larval development. Conversely, in the case of B. stephanieae larvae, evidence does not support a mutualistic relationship. Our study supports the utilization of H+-ATPase expression as a marker for assessing Symbiodinium-invertebrate relationships with applications for the differentiation of symbiotic and non-symbiotic associations. At the same time, insights from a single marker gene approach are limited and future studies should direct the identification of additional symbiosis-specific genes, ideally from both symbiont and host.

6.
Artigo em Inglês | MEDLINE | ID: mdl-27904505

RESUMO

BACKGROUND: Scleractinian corals (stony corals) are the most abundant reef-forming cnidarians found in coral reefs throughout the world. Despite their abundance and ecological importance, information about the diversity of their toxins and their biological activities is very scarce. In this study, the chemical composition and the biological activities of the aqueous extracts of Pseudodiploria strigosa, Porites astreoides and Siderastrea siderea, three scleractinian corals from the Mexican Caribbean, have been assessed for the first time. METHODS: Toxicity of the extracts was assessed in crickets; the presence of cytolysins was detected by the hemolysis assay; the vasoconstrictor activity was determined by the isolated rat aortic ring assay; the nociceptive activity was evaluated by the formalin test. The presence of phospholipases A2 (PLA2), serine proteases, and hyaluronidases was determined by enzymatic methods. Low-molecular-weight fractions were obtained by gel filtration chromatography and ultrafiltration. RESULTS: Extracts from the three species were toxic to crickets, induced hemolysis in human and rat erythrocytes, produced vasoconstriction on isolated rat aortic rings, and presented phospholipase A2 and serine-protease activity. Despite the fact that these corals are not considered to be harmless to humans, the extracts generated significant nociceptive responses. The matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry analysis of the low-molecular-weight fractions revealed the presence of peptides within a mass range of 3000 to 6000 Da. These fractions were toxic to crickets and two of them induced a transitory vasoconstrictor effect on isolated rat aortic rings. CONCLUSION: This study suggests that scleractinian corals produce low-molecular-weight peptides that are lethal to crickets and induce vasoconstriction.

7.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(4): 2911-2, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26119126

RESUMO

Dendrophylliidae is one of the few monophyletic families within the Scleractinia that embraces zooxanthellate and azooxanthellate species represented by both solitary and colonial forms. Among the exclusively azooxanthellate genera, Dendrophyllia is reported worldwide from 1 to 1200 m deep. To date, although three complete mitochondrial (mt) genomes from representatives of the family are available, only that from Turbinaria peltata has been formally published. Here we describe the complete nucleotide sequence of the mt genome from Dendrophyllia arbuscula that is 19 069 bp in length and comprises two rDNAs, two tRNAs, and 13 protein-coding genes arranged in the canonical scleractinian mt gene order. No genes overlap, resulting in the presence of 18 intergenic spacers and one of the longest scleractinian mt genome sequenced to date.


Assuntos
Antozoários/classificação , Antozoários/genética , Genoma Mitocondrial , Genômica , Animais , Composição de Bases , Genes Mitocondriais , Tamanho do Genoma , Genômica/métodos , Filogenia
8.
J. venom. anim. toxins incl. trop. dis ; J. venom. anim. toxins incl. trop. dis;22: 32, 2016. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-954792

RESUMO

Background: Scleractinian corals (stony corals) are the most abundant reef-forming cnidarians found in coral reefs throughout the world. Despite their abundance and ecological importance, information about the diversity of their toxins and their biological activities is very scarce. In this study, the chemical composition and the biological activities of the aqueous extracts of Pseudodiploria strigosa, Porites astreoides and Siderastrea siderea, three scleractinian corals from the Mexican Caribbean, have been assessed for the first time. Methods: Toxicity of the extracts was assessed in crickets; the presence of cytolysins was detected by the hemolysis assay; the vasoconstrictor activity was determined by the isolated rat aortic ring assay; the nociceptive activity was evaluated by the formalin test. The presence of phospholipases A2 (PLA2), serine proteases, and hyaluronidases was determined by enzymatic methods. Low-molecular-weight fractions were obtained by gel filtration chromatography and ultrafiltration. Results: Extracts from the three species were toxic to crickets, induced hemolysis in human and rat erythrocytes, produced vasoconstriction on isolated rat aortic rings, and presented phospholipase A2 and serine-protease activity. Despite the fact that these corals are not considered to be harmless to humans, the extracts generated significant nociceptive responses. The matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry analysis of the low-molecular-weight fractions revealed the presence of peptides within a mass range of 3000 to 6000 Da. These fractions were toxic to crickets and two of them induced a transitory vasoconstrictor effect on isolated rat aortic rings. Conclusion: This study suggests that scleractinian corals produce low-molecular-weight peptides that are lethal to crickets and induce vasoconstriction.(AU)


Assuntos
Animais , Vasoconstrição , Cnidários/crescimento & desenvolvimento , Bancos de Espécimes Biológicos , Dor Nociceptiva , Hemólise , Equilíbrio Ecológico
9.
J. venom. anim. toxins incl. trop. dis ; J. venom. anim. toxins incl. trop. dis;22: [1-14], 2016. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484659

RESUMO

Scleractinian corals (stony corals) are the most abundant reef-forming cnidarians found in coral reefs throughout the world. Despite their abundance and ecological importance, information about the diversity of their toxins and their biological activities is very scarce. In this study, the chemical composition and the biological activities of the aqueous extracts of Pseudodiploria strigosa, Porites astreoides and Siderastrea siderea, three scleractinian corals from the Mexican Caribbean, have been assessed for the first time. Methods: Toxicity of the extracts was assessed in crickets; the presence of cytolysins was detected by the hemolysis assay; the vasoconstrictor activity was determined by the isolated rat aortic ring assay; the nociceptive activity was evaluated by the formalin test. The presence of phospholipases A2 (PLA2), serine proteases, and hyaluronidases was determined by enzymatic methods. Low-molecular-weight fractions were obtained by gel filtration chromatography and ultrafiltration. Results: Extracts from the three species were toxic to crickets, induced hemolysis in human and rat erythrocytes, produced vasoconstriction on isolated rat aortic rings, and presented phospholipase A2 and serine-protease activity. Despite the fact that these corals are not considered to be harmless to humans, the extracts generated significant nociceptive responses. The matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry analysis of the low-molecular-weight fractions revealed the presence of peptides within a mass range of 3000 to 6000 Da. These fractions were toxic to crickets and two of them induced a transitory vasoconstrictor effect on isolated rat aortic rings. Conclusion: This study suggests that scleractinian corals produce low-molecular-weight peptides that are lethal to crickets and induce vasoconstriction.


Assuntos
Antozoários/classificação , Antozoários/microbiologia , Antozoários/química , Biota
10.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 22: [1-14], Janeiro 19, 2016. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: vti-15708

RESUMO

Scleractinian corals (stony corals) are the most abundant reef-forming cnidarians found in coral reefs throughout the world. Despite their abundance and ecological importance, information about the diversity of their toxins and their biological activities is very scarce. In this study, the chemical composition and the biological activities of the aqueous extracts of Pseudodiploria strigosa, Porites astreoides and Siderastrea siderea, three scleractinian corals from the Mexican Caribbean, have been assessed for the first time. Methods: Toxicity of the extracts was assessed in crickets; the presence of cytolysins was detected by the hemolysis assay; the vasoconstrictor activity was determined by the isolated rat aortic ring assay; the nociceptive activity was evaluated by the formalin test. The presence of phospholipases A2 (PLA2), serine proteases, and hyaluronidases was determined by enzymatic methods. Low-molecular-weight fractions were obtained by gel filtration chromatography and ultrafiltration. Results: Extracts from the three species were toxic to crickets, induced hemolysis in human and rat erythrocytes, produced vasoconstriction on isolated rat aortic rings, and presented phospholipase A2 and serine-protease activity. Despite the fact that these corals are not considered to be harmless to humans, the extracts generated significant nociceptive responses. The matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry analysis of the low-molecular-weight fractions revealed the presence of peptides within a mass range of 3000 to 6000 Da. These fractions were toxic to crickets and two of them induced a transitory vasoconstrictor effect on isolated rat aortic rings. Conclusion: This study suggests that scleractinian corals produce low-molecular-weight peptides that are lethal to crickets and induce vasoconstriction.(AU)


Assuntos
Antozoários/classificação , Antozoários/microbiologia , Antozoários/química , Biota
11.
Front Microbiol ; 6: 1038, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26483769

RESUMO

The aim of this study was to investigate the planktonic and the holobiont Madracis decactis (Scleractinia) microbial diversity along a turbulence-driven upwelling event, in the world's most isolated tropical island, St Peter and St Paul Archipelago (SPSPA, Brazil). Twenty one metagenomes were obtained for seawater (N = 12), healthy and bleached holobionts (N = 9) before, during and after the episode of high seawater turbulence and upwelling. Microbial assemblages differed between low turbulence-low nutrient (LLR) and high-turbulence-high nutrient (HHR) regimes in seawater. During LLR there was a balance between autotrophy and heterotrophy in the bacterioplankton and the ratio cyanobacteria:heterotrophs ~1 (C:H). Prochlorales, unclassified Alphaproteobacteria and Euryarchaeota were the dominant bacteria and archaea, respectively. Basic metabolisms and cyanobacterial phages characterized the LLR. During HHR C:H < < 0.05 and Gammaproteobacteria approximated 50% of the most abundant organisms in seawater. Alteromonadales, Oceanospirillales, and Thaumarchaeota were the dominant bacteria and archaea. Prevailing metabolisms were related to membrane transport, virulence, disease, and defense. Phages targeting heterotrophs and virulence factor genes characterized HHR. Shifts were also observed in coral microbiomes, according to both annotation-indepent and -dependent methods. HHR bleached corals metagenomes were the most dissimilar and could be distinguished by their di- and tetranucleotides frequencies, Iron Acquision metabolism and virulence genes, such as V. cholerae-related virulence factors. The healthy coral holobiont was shown to be less sensitive to transient seawater-related perturbations than the diseased animals. A conceptual model for the turbulence-induced shifts is put forward.

12.
Artigo em Português | VETINDEX | ID: vti-437838

RESUMO

Exotic sun corals or cup corals (Tubastraea coccinea Lesson, 1829 and T. tagusensis Wells, 1982) have invaded sessile biological communities on rocky shores at Ilha Grande Bay, Rio de Janeiro, Brazil. Artificial structures (piers, docks or decks) were selected at four sites in Ilha Grande and compared with natural substrates on the adjacent rocky shore by quantifying the density of each species of Tubastraea, as well as the percentage coverage of the benthic biota. The overall average density of Tubastraea tagusensis was 80.3 individuals.m-2, about double that of T. coccinea. Both invasive species modified the structure of the invaded communities as relative abundance and richness of the species changed due to their presence. Tubastraea coccinea was more abundant on artificial substrates than on natural ones but no difference was detected in the abundance of Tubastraea tagusensis between substrates. The abundance of both species also varied with depth and site and a positive relation between artificial substratum age and abundance of the corals was observed. Apparently T. tagusensis is competitively superior to T. coccinea with a greater ability to occupy/invade native communities on natural substrates. Both species showed high competitive potential and can use artificial substrates to start to establish in new areas.


Os corais exóticos coral-sol (Tubastraea coccinea Lesson, 1829 e T. tagusensis Wells, 1982) invadiram as comunidades biológicas sésseis dos costões rochosos da Baía da Ilha Grande, Rio de Janeiro, Brasil. Estruturas artificiais (piers, decks ou cais) foram selecionadas em quatro locais na Ilha Grande, e comparadas com substratos naturais adjacentes através de quantificação da densidade de cada espécie de Tubastraea, além da porcentagem de cobertura da biota bêntica. A densidade média geral de Tubastraea tagusensis foi de 80,3 indivíduos.m-2, aproximadamente o dobro encontrado para T. coccinea. Tendo em vista que sua presença alterou as abundâncias relativas e a riqueza de espécies, ambas as espécies invasoras modificaram a estrutura das comunidades invadidas. Tubastraea coccinea foi mais abundante em substratos artificiais do que naturais, porém, não foi detectada diferença na abundância de Tubastraea tagusensis entre substratos. A abundância de ambas as espécies variou com a profundidade e o local, e houve uma relação positiva entre a idade do substrato artificial e a abundância dos corais. Aparentemente T. tagusensis é competitivamente superior à T. coccinea, com uma inserção maior nas comunidades nativas em substratos naturais. Ambas as espécies tem grande potencial competitivo e podem utilizar substratos artificiais para iniciar seu estabelecimento em novos locais.

13.
Artigo em Português | LILACS-Express | VETINDEX | ID: biblio-1482683

RESUMO

Exotic sun corals or cup corals (Tubastraea coccinea Lesson, 1829 and T. tagusensis Wells, 1982) have invaded sessile biological communities on rocky shores at Ilha Grande Bay, Rio de Janeiro, Brazil. Artificial structures (piers, docks or decks) were selected at four sites in Ilha Grande and compared with natural substrates on the adjacent rocky shore by quantifying the density of each species of Tubastraea, as well as the percentage coverage of the benthic biota. The overall average density of Tubastraea tagusensis was 80.3 individuals.m-2, about double that of T. coccinea. Both invasive species modified the structure of the invaded communities as relative abundance and richness of the species changed due to their presence. Tubastraea coccinea was more abundant on artificial substrates than on natural ones but no difference was detected in the abundance of Tubastraea tagusensis between substrates. The abundance of both species also varied with depth and site and a positive relation between artificial substratum age and abundance of the corals was observed. Apparently T. tagusensis is competitively superior to T. coccinea with a greater ability to occupy/invade native communities on natural substrates. Both species showed high competitive potential and can use artificial substrates to start to establish in new areas.


Os corais exóticos coral-sol (Tubastraea coccinea Lesson, 1829 e T. tagusensis Wells, 1982) invadiram as comunidades biológicas sésseis dos costões rochosos da Baía da Ilha Grande, Rio de Janeiro, Brasil. Estruturas artificiais (piers, decks ou cais) foram selecionadas em quatro locais na Ilha Grande, e comparadas com substratos naturais adjacentes através de quantificação da densidade de cada espécie de Tubastraea, além da porcentagem de cobertura da biota bêntica. A densidade média geral de Tubastraea tagusensis foi de 80,3 indivíduos.m-2, aproximadamente o dobro encontrado para T. coccinea. Tendo em vista que sua presença alterou as abundâncias relativas e a riqueza de espécies, ambas as espécies invasoras modificaram a estrutura das comunidades invadidas. Tubastraea coccinea foi mais abundante em substratos artificiais do que naturais, porém, não foi detectada diferença na abundância de Tubastraea tagusensis entre substratos. A abundância de ambas as espécies variou com a profundidade e o local, e houve uma relação positiva entre a idade do substrato artificial e a abundância dos corais. Aparentemente T. tagusensis é competitivamente superior à T. coccinea, com uma inserção maior nas comunidades nativas em substratos naturais. Ambas as espécies tem grande potencial competitivo e podem utilizar substratos artificiais para iniciar seu estabelecimento em novos locais.

14.
Univ. sci ; 16(3): 200-218, sept.-dic. 2011. mapas, tab, graf
Artigo em Inglês | LILACS | ID: lil-619188

RESUMO

Revisión sobre el reclutamiento de corales duros (Cnidaria: Scleractinia) en Colombia. El reclutamiento, definido y medido como la incorporación de nuevos individuos (ej. juveniles de coral) a la población, es considerado en arrecifes coralinos como un proceso fundamental por parte de ecólogos, evolucionistas y conservacionistas debido a que determina de forma directa la estructura y función de las poblaciones. Además, debido a que la mayor parte de las poblaciones coralinas se auto-abastecen (self-seeding), fallas en el reclutamiento conducirían a extinción local. Indirectamente, el reclutamiento afecta la renovación y el mantenimiento de las comunidades coralinas presentes y futuras, la biodiversidad (efecto bottom-up) y por lo tanto, la capacidad de resiliencia del ecosistema arrecifal. Este proceso ha sido empleado como una medida del éxito reproductivo de individuos (fitness) y representa la etapa final del proceso de dispersión que conlleva a la conectividad poblacional. Es por lo anterior, que esta variable ha sido propuesta como un indicador del estado de salud de los arrecifes en áreas marinas protegidas y es un elemento fundamental para la toma de decisiones de manejo y conservación. Generar planes de manejo que propendan a minimizar impactos, rehabilitar y conservar los arrecifes del país es una necesidad que requiere en primera instancia de una revisión e integración de la literatura existente sobre reclutamiento de corales escleractínios en Colombia, al igual que estudios de campo a mayor escala. Lo anterior nos motivó a analizar y sintetizar la literatura existente con el ánimo de determinar el estado del conocimiento, extraer patrones, identificar vacíos y sugerir líneas de investigación...


Recruitment, defined and measured as the incorporation of new individuals (i.e. coral juveniles) into a population, is a fundamental process for ecologists, evolutionists and conservationists due to its direct effect on population structure and function. Because most coral populations are self-feeding, a breakdown in recruitment would lead to local extinction. Recruitment indirectly affects both renewal and maintenance of existing and future coral communities, coral reef biodiversity (bottom-up effect) and therefore coral reef resilience. This process has been used as an indirect measure of individual reproductive success (fitness) and is the final stage of larval dispersal leading to population connectivity. As a result, recruitment has been proposed as an indicator of coral-reef health in marine protected areas, as well as a central aspect of the decision-making process concerning management and conservation. The creation of management plans to promote impact mitigation, rehabilitation and conservation of the Colombian coral reefs is a necessity that requires firstly, a review and integration of existing literature on scleractinian coral recruitment in Colombia and secondly, larger scale field studies. This motivated us to summarize and analyze all existing information on coral recruitment to determine the state of knowledge, isolate patterns, identify gaps, and suggest future lines of research...


Revisão sobre o recrutamento de corais pétreos (Cnidaria: Scleractinia) na Colômbia. O recrutamento, definido e medido como a entrada de novos indivíduos para a população (exemplo juvenis do coral), tem sido considerado como um processo fundamental pelos ecólogos, os evolucionistas e conservacionistas que trabalham em recifes de coral, ja que determina diretamente a estrutura e a função das populações. Além disso, dado que a maioria das populações de coral produz seus próprios juvenis (self-seeding), falhas no recrutamento levam à extinção local. Indiretamente, o recrutamento afeta a renovação-manutenção das comunidades de corais presentes e futuras, a biodiversidade (efeito bottom-up) e, portanto, da resiliência do ecossistema recifal. Este processo tem sido utilizado como uma medida de sucesso reprodutivo dos indivíduos (fitness) e representa o estágio final do processo de dispersão que leva a conectividade populacional. Pelo exposto, esta variável tem sido proposta como um indicador da saúde dos recifes nas áreas marinhas protegidas e é um elemento chave na tomada de decisões de gestão e conservação. Gerar planos de ação que tendem a minimizar impactos, recuperar e preservar os recifes do país é uma necessidade que requer, em primeira instância, uma revisão e integração da literatura existente sobre o recrutamento dos corais escleractíneos na Colômbia; assim mesmo, estudos de campo a escala maior. Isso levou a analisar e sintetizar a literatura existente com o objetivo de determinar o estado do conhecimento, abstrair padrões, identificar vazios e sugerir linhas de pesquisa...


Assuntos
Recifes de Corais , Biodiversidade , Biologia Marinha , Ecossistema , Colômbia
15.
Biota neotrop. (Online, Ed. port.) ; 9(2): 35-43, Apr.-June 2009. ilus, mapas, tab
Artigo em Português | LILACS | ID: lil-529206

RESUMO

A pesca demersal voltada as espécies de peixes (i.e. Lophius gastrophisus, Urophisys brasiliensis, Genipterus brasiliensis) e crustáceos (Chaceon ramosae e Chaceon sp.), com grande valor comercial no talude continental superior do sul do Brasil aumentou significativamente nas últimas décadas. A compilação de todos os dados até então publicados acerca dos pontos de ocorrência dos corais escleractíneos azooxantelados em águas sul-brasileiras entre 24º e 35º S, sobrepostos com as principais áreas de atuação das quatro modalidades de pesca demersais (arrasto de profundidade, emalhe e espinhel de fundo e covos), demonstrou que as frotas em questão vêm utilizando as áreas com ocorrência de corais, como principais áreas de esforço, indicando que os recifes de profundidade possuem elevada importância ecológica perante os ecossistemas da plataforma e talude continental, sendo importantes reservatórios da biodiversidade marinha profunda. Entretanto, desde as fases iniciais desta exploração evidenciou-se através de relatos de observadores de bordo, a captura, como "bycatch", de grandes quantidades de corais de profundidade. Desta maneira, visando não só apenas a proteção dos ecossistemas coralíneos de profundidade, mas também a sustentabilidade econômica da pesca, é recomendada a criação de áreas de exclusão da pesca demersal em locais com ocorrência de Scleractinia azooxantelados.


Demersal fishing of important commercial fishes (Lophius gastrophisus, Urophisys brasiliensis and Genipterus brasiliensis) and crustaceans (Chaceon ramosae and Chaceon sp.) along the upper slope off southern Brazil has increased dramatically in the last decade. Compilation of available data on the distribution of azooxanthellate corals between 24º and 35º S, compared with the distribution of bottom-longline, bottom-gillnets, trawl and trap fisheries shows that commercial fishing takes place over coral areas, providing evidence deep-sea reefs are important reservoirs of deep marine biodiversity. Since the initial phase of exploitation by demersal fisheries, onboard observers are describing large captures of corals as "bycatch" suggesting deep-sea communities are being destroyed even before being studied. In order to ensure protection of deep-sea coral ecosystems and economic sustainability of demersal fisheries in southern Brazilian waters, adoption of excluded fishing areas in those locations where azooxanthellate Scleractinia occur is strongly recommended.


Assuntos
Biodiversidade , Recifes de Corais , Ecossistema , Política Ambiental , Pesqueiros , Peixes , Indústria Pesqueira
16.
Artigo em Português | VETINDEX | ID: vti-437683

RESUMO

Amongst organisms reported in deep waters (> 100 m) from southern Brazil, the azooxanthellate scleractinians are of particular importance due to their capacity to form habitats which attract many species of invertebrates and vertebrates. Through statistical analysis of distribution, identification of specimens deposited in scientific collections, and revision of all preterite records of azooxanthellate scleractinians from southern and part of southeastern coast of Brazil, was noted that the coordinates covered by the present study represent an transitional distributional area between the Caribbean and marginal Antarctic fauna, especially for the solitary species. From a vertical distribution analysis, an increase in the number of species in the sector between the external continental shelve and 500 m depth was observed. A grouping analysis was performed, allowing the discrimination of 6 association biotopes of corals. Thus, we present the first attempt to understand the distribution of this fauna from the continental shelf and continental slope of southern Brazil, between 24°S and 34°S.


Dentre os organismos registrados para águas profundas (> 100 m) no sul do Brasil, podemos destacar os corais azooxantelados pertencentes a ordem Scleractinia. Através de análises estatísticas, identificação de espécimes depositados em coleções científicas, e compilação de todos os registros pretéritos destes cnidarios ocorrentes no sul e parte do sudeste do Brasil, foi possível constatar que as coordenadas abrangidas no presente estudo representam uma área de transição entre os corais azooxantelados ocorrentes ao norte e as espécies mais características das zonas polares, principalmente em relação às espécies solitárias. Com a análise da distribuição batimétrica, foi observado um significativo aumento no número de espécies entre o setor de plataforma externa e 500 m de profundidade. Finalizando, foi realizada a análise de agrupamento, o que permitiu discriminar a formação de 6 biótopos das associações de corais azooxantelados para a área de estudo. Desta forma, apresentamos a primeira tentativa de se compreender a distribuição desta pouco conhecida fauna da plataforma e talude continental superior, entre 24ºS e 34ºS.

17.
Artigo em Português | LILACS-Express | VETINDEX | ID: biblio-1484079

RESUMO

Amongst organisms reported in deep waters (> 100 m) from southern Brazil, the azooxanthellate scleractinians are of particular importance due to their capacity to form habitats which attract many species of invertebrates and vertebrates. Through statistical analysis of distribution, identification of specimens deposited in scientific collections, and revision of all preterite records of azooxanthellate scleractinians from southern and part of southeastern coast of Brazil, was noted that the coordinates covered by the present study represent an transitional distributional area between the Caribbean and marginal Antarctic fauna, especially for the solitary species. From a vertical distribution analysis, an increase in the number of species in the sector between the external continental shelve and 500 m depth was observed. A grouping analysis was performed, allowing the discrimination of 6 association biotopes of corals. Thus, we present the first attempt to understand the distribution of this fauna from the continental shelf and continental slope of southern Brazil, between 24°S and 34°S.


Dentre os organismos registrados para águas profundas (> 100 m) no sul do Brasil, podemos destacar os corais azooxantelados pertencentes a ordem Scleractinia. Através de análises estatísticas, identificação de espécimes depositados em coleções científicas, e compilação de todos os registros pretéritos destes cnidarios ocorrentes no sul e parte do sudeste do Brasil, foi possível constatar que as coordenadas abrangidas no presente estudo representam uma área de transição entre os corais azooxantelados ocorrentes ao norte e as espécies mais características das zonas polares, principalmente em relação às espécies solitárias. Com a análise da distribuição batimétrica, foi observado um significativo aumento no número de espécies entre o setor de plataforma externa e 500 m de profundidade. Finalizando, foi realizada a análise de agrupamento, o que permitiu discriminar a formação de 6 biótopos das associações de corais azooxantelados para a área de estudo. Desta forma, apresentamos a primeira tentativa de se compreender a distribuição desta pouco conhecida fauna da plataforma e talude continental superior, entre 24ºS e 34ºS.

18.
Artigo em Português | VETINDEX | ID: vti-442492

RESUMO

Large portions of the Brazilian continental shelf and continental slope do not have detailed maps about the sedimentological mosaics, manly due to the high costs of specific oceanographic deep-water cruises. Using all records (totalizing 169 stations) of deep-sea Scleractinia azooxanthellate corals from southern Brazil between 24° and 35°S, and separating them in three different groups, the present study intends to add to the actual knowledge of the superficial sedimentology off southern Brazil, demonstrating that the records of this cnidarians can be used as tools for mapping hard, soft, and biodetrictic deep-sea substrate.


Grande parte da plataforma e talude continental sul-brasileiro não possui detalhamento acerca dos mosaicos sedimentológicos, em parte devido aos elevados custos de cruzeiros oceanográficos específicos para o mapeamento sedimentológico de águas profundas. Visando contribuir com o conhecimento acerca da cobertura sedimentar ocorrente ao largo do sul do Brasil, o presente trabalho agrega informações referentes à fauna coralínea (ordem Scleractinia) nesta área (totalizando 169 estações), utilizando os registros e informações referentes ao tipo de substrato utilizado pelas 35 espécies de corais analisadas como ferramenta para a identificação e mapeamento de áreas de ocorrência de substratos não-consolidados, biodetríticos e consolidados.

19.
Pap. avulsos zool ; 48(2)2008.
Artigo em Português | LILACS-Express | VETINDEX | ID: biblio-1486388

RESUMO

Large portions of the Brazilian continental shelf and continental slope do not have detailed maps about the sedimentological mosaics, manly due to the high costs of specific oceanographic deep-water cruises. Using all records (totalizing 169 stations) of deep-sea Scleractinia azooxanthellate corals from southern Brazil between 24° and 35°S, and separating them in three different groups, the present study intends to add to the actual knowledge of the superficial sedimentology off southern Brazil, demonstrating that the records of this cnidarians can be used as tools for mapping hard, soft, and biodetrictic deep-sea substrate.


Grande parte da plataforma e talude continental sul-brasileiro não possui detalhamento acerca dos mosaicos sedimentológicos, em parte devido aos elevados custos de cruzeiros oceanográficos específicos para o mapeamento sedimentológico de águas profundas. Visando contribuir com o conhecimento acerca da cobertura sedimentar ocorrente ao largo do sul do Brasil, o presente trabalho agrega informações referentes à fauna coralínea (ordem Scleractinia) nesta área (totalizando 169 estações), utilizando os registros e informações referentes ao tipo de substrato utilizado pelas 35 espécies de corais analisadas como ferramenta para a identificação e mapeamento de áreas de ocorrência de substratos não-consolidados, biodetríticos e consolidados.

20.
Braz. J. Biol. ; 65(4)2005.
Artigo em Inglês | VETINDEX | ID: vti-446053

RESUMO

The distribution and abundance of azooxanthellate coral Tubastraea Lesson, 1829 were examined at different depths and their slope preference was measured on rocky shores on Ilha Grande, Brazil. Tubastraea is an ahermatypic scleractinian nonindigenous to Brazil, which probably arrived on a ship's hull or oil platform in the late 1980's. The exotic coral was found along a great geographic range of the Canal Central of Ilha Grande, extending over a distance of 25 km. The abundance of Tubastraea was quantified by depth, using three different sampling methods: colony density, visual estimation and intercept points (100) for percentage of cover. Tubastraea showed ample tolerance to temperature and desiccation since it was found more abundantly in very shallow waters (0.1-0.5 m), despite the fact that hard substratum is available at greater depths at all the stations sampled. At most sites, 1 to 5 colonies per 0.25 m² were found most frequently, but occasionally more than 50 colonies were found per 0.25 m², indicating a somewhat gregarious spatial distribution for this coral. The coral Tubastraea was found to occupy slopes of every possible angle in the Canal Central of Ilha Grande, but more colonies were found occupying slopes of 80 to 100°. Therefore, its insensitivity to angles of recruitment and its tolerance for different depths makes it an organism with great ecological tolerance, with a potential to colonize new areas and increase its current range in Brazil's coastal waters.


A distribuição e abundância do coral azooxantelado Tubastraea Lesson, 1829 foram estimadas em diferentes profundidades e inferido seu ângulo preferencial de ocorrência em costões rochosos da Ilha Grande, Brasil. Tubastraea é um escleractínio ahermatípico introduzido no Brasil que, provavelmente, chegou incrustado em casco de navios e/ou plataformas de petróleo na década de 80. O coral exótico foi encontrado em uma extensão geográfica de 25 km no Canal Central da Ilha Grande. A abundância de Tubastraea foi quantificada em relação à profundidade usando três diferentes métodos: densidade de colônias e porcentagem de cobertura por estimativa visual e pontos de intersecção. O coral Tubastraea demonstrou ter ampla tolerância à temperatura e dessecação, sendo encontrado em águas muito rasas (0,1-0,5 m), apesar de haver substrato consolidado disponível em maiores profundidades em todas as estações amostradas. Em todas as estações 1-5 colônias foram mais freqüentemente encontradas em cada 0,25 m², porém, ocasionalmente, mais que 50 colônias por 0,25 m² foram encontradas, indicando um padrão de agregação na distribuição espacial deste coral. Tubastraea foi encontrado ocupando todos os possíveis ângulos de inclinação no Canal Central da Ilha Grande, porém, a maior parte das colônias foram encontradas ocupando ângulos entre 80-100°. Desta forma, a amplitude de inclinação de substrato e profundidades viáveis ao recrutamento do coral indicam que este organismo, de grande tolerância ecológica, tem a potencialidade de colonizar novas áreas e aumentar sua distribuição no Brasil.

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