Publicação
Coral reef microbiota and the potential of humic substances to improve reef resilience
| Resumo: | Coral reef ecosystems are renowned for their biodiversity and for their socioeconomic and ecological significance. In recent decades, however, the ecological balance within coral reefs has been disrupted leading to large-scale loss of coral reef habitat. El Niño Southern Oscillation (ENSO)-induced elevated temperatures and intense UVB radiation have resulted in global coral bleaching events. Meanwhile, large-scale urbanisation of coastal areas has further degraded reef ecosystems at local scales by increasing the inflow of nutrients and pollutants, and favoring the proliferation of benthic cyanobacterial mats over corals. To effectively protect and restore coral reefs, it is crucial to improve our understanding of these emerging microbial colonizers. Additionally, it is of paramount importance to identify local factors, which influence coral reef microbial communities and reef resilience. Previous observational studies have suggested that terrestrially-derived compounds, particularly humic substances (HS), can protect coral reefs from thermal stress. However, no study has, until now, systematically tested this hypothesis. This thesis addresses this gap by investigating 1) the diversity, distribution and biofouling activity of benthic cyanobacterial mats, 2) the suitability of an experimental life support system (ELLS) to study coral reef microbial communities under controlled conditions, 3) the effects of terrestriallyderived HS on coral reef microbial communities and 4) the potential of HS in augmenting coral reef resilience to elevated temperatures and UVB radiation. The goals were achieved by employing a comprehensive approach that combined field surveys, the development and subsequent utilization of an experimental life support system (ELSS), and chemical and microbial community analyses. Field surveys were performed to document and sample benthic cyanobacterial mats at reefs surrounding the island of Koh Tao (Gulf of Thailand). To obtain information on the bacterial community composition, samples were analysed using 16S rRNA gene high-throughput sequencing (HTS). The results of this study are discussed in chapter two and showed that mat colour (morphotype), substrate type and geographic location only explained a small part of the total variation in bacterial composition. Proteobacteria, Cyanobacteria, Bacteroidetes and Planctomycetes were the four most abundant phyla and occurred in all samples. Mats, moreover, were composed of potentially toxin producing bacteria, including the cyanobacterial genera Blennothrix, Hormoscilla, and the related proteobacterial species Vibrio harveyi and Vibrio neptunius. These findings improved our understanding of cyanobacterial mat ecology, which will help to guide conservation efforts aimed at improving coral reef health, especially in the light of future climate conditions which have been predicted to enhance mat proliferation at the expense of coral growth. In chapter three, the ELSS is described in detail. The system consisted of 32 independent microcosms, each containing coral reef sediment, artificial seawater, and five reef organisms. These included two hard corals Montipora digitata and Montipora capricornis, a soft coral Sarcophyton glaucum, a zoanthid Zoanthus sp., and a sponge Chondrilla sp.. The system was validated by comparing physiochemical conditions, coral photosynthetic efficiency and both environmental and host-associated bacterial communities sampled in microcosms and natural reef sites. The results supported the suitability of the ELSS to study coral reef biotopes and their associated bacterial communities exposed to a suite of environmental parameters. The developed ELSS was subsequently used to test to what extent HS are able to mitigate the adverse effects of elevated temperature and UVB radiation on coral photosynthetic activity, and environmental and host-associated bacterial communities. Photosynthetic activity was estimated by measuring the chlorophyll fluorescence of the corals and bacterial communities were studied using 16S rRNA gene HTS analysis. The results are described in chapters four, five and six and indicate that corals in HS-supplemented microcosms had significantly higher photosynthetic activities than those in microcosms subjected to elevated temperature and UVB radiation. HS supplementation, furthermore, significantly influenced the composition of sediment, water and host-associated bacterial communities. Individuals of M. digitata, S. glaucum and Chondrilla sp. in HS supplemented microcosms contained unique bacterial communities enriched with groups of potentially beneficial bacteria. In the hard coral M. digitata, we observed a significant interactive effect of HS, UVB, and temperature, whereby bacterial communities were more resilient to the combined effects of temperature and UVB radiation in microcosms supplemented with HS. These findings have significant repercussions for reef resilience in the face of increasing climate-induced stressors and highlight the importance of restoring coastal forests, known as the main sources of HS in coastal environments, to protect coral reefs. |
|---|---|
| Autores principais: | Stuij, Tamara Maria |
| Assunto: | Cyanobacteria Microbial mat 16S rRNA gene amplicon sequencing Bacterial communities Humic substances Terrestrial organic matter ENSO Climate change Montipora digitata Montipora capricornis Sarcophyton glaucum Chondrilla sp. |
| Ano: | 2024 |
| País: | Portugal |
| Tipo de documento: | tese de doutoramento |
| Tipo de acesso: | acesso aberto |
| Instituição associada: | Universidade de Aveiro |
| Idioma: | inglês |
| Origem: | RIA - Repositório Institucional da Universidade de Aveiro |
| _version_ | 1866173224721580032 |
|---|---|
| author | Stuij, Tamara Maria |
| author_facet | Stuij, Tamara Maria |
| author_role | author |
| country_str | PT |
| creators_json_txt | [{\"Person.name\":\"Stuij, Tamara Maria\"}] |
| datacite.creators.creator.creatorName.fl_str_mv | Stuij, Tamara Maria |
| datacite.date.Accepted.fl_str_mv | 2024-04-20T00:00:00Z |
| datacite.date.available.fl_str_mv | 2024-05-20T10:20:59Z |
| datacite.date.embargoed.fl_str_mv | 2024-05-20T10:20:59Z |
| datacite.rights.fl_str_mv | http://purl.org/coar/access_right/c_abf2 |
| datacite.subjects.subject.fl_str_mv | Cyanobacteria Microbial mat 16S rRNA gene amplicon sequencing Bacterial communities Humic substances Terrestrial organic matter ENSO Climate change Montipora digitata Montipora capricornis Sarcophyton glaucum Chondrilla sp. |
| datacite.titles.title.fl_str_mv | Coral reef microbiota and the potential of humic substances to improve reef resilience |
| dc.creator.none.fl_str_mv | Stuij, Tamara Maria |
| dc.date.Accepted.fl_str_mv | 2024-04-20T00:00:00Z |
| dc.date.available.fl_str_mv | 2024-05-20T10:20:59Z |
| dc.date.embargoed.fl_str_mv | 2024-05-20T10:20:59Z |
| dc.description.none.fl_str_mv | Os ecossistemas de recifes de coral são conhecidos pela sua biodiversidade, importância socioeconômica e ecológica. No entanto, nas últimas décadas, a disrupção do equilíbrio ecológico nos recifes de coral resultaram em reduções consideráveis deste habitat. As temperaturas elevadas induzidas pelo ENSO e a intensa radiação UVB têm causado eventos globais de branqueamento de corais. Ao mesmo tempo, a urbanização em larga escala das áreas costeiras degradaram ainda mais os ecossistemas de recifes em escalas locais, aumentando o influxo de nutrientes e poluentes e favorecendo a proliferação de tapetes bênticos de cianobactérias sobre os corais. Para proteger e restaurar efetivamente os recifes de coral, é crucial aprofundar a nossa compreensão destes colonizadores microbianos emergentes. Além disso, é de extrema importância identificar fatores locais que influenciam as comunidades microbianas e a resiliência dos recifes de coral. Estudos observacionais anteriores sugerem que compostos derivados do solo, em especial as substâncias húmicas (HS), podem proteger os recifes de coral de stresse térmico. Ainda assim, até hoje, nenhum estudo testou sistematicamente essa hipótese. Esta tese aborda essa lacuna investigando 1) a diversidade, distribuição e atividade de bioincrustação de tapetes bênticos de cianobactérias, 2) a adequação de um sistema experimental de suporte de vida (ELSS) para estudar comunidades microbianas de recifes de coral em condições controladas, 3) os efeitos das HS derivadas do solo nas comunidades microbianas de recifes de coral e 4) o potencial das HS em aumentar a resiliência dos recifes de coral a temperaturas elevadas e radiação UVB. Os objetivos foram alcançados através de uma abordagem abrangente que combinou saídas de campo, o desenvolvimento e a subsequente utilização de um sistema experimental de suporte de vida e análises químicas e das comunidades microbianas. As saídas de campo foram realizadas para documentar e coletar amostras de tapetes bênticos de cianobacterias nos recifes ao redor da ilha de Koh Tao (Golfo da Tailândia). Para obter informações sobre a composição da comunidade bacteriana, as amostras foram analisadas com recurso a highthroughput sequencing (HTS) do gene 16S rRNA. Os resultados das saídas de campo são discutidos no capítulo dois e demonstram que a cor do tapete (morfotipo), tipo de substrato e localização geográfica explicam apenas uma pequena parte da variação total da composição bacteriana. Proteobacteria, Cianobacteria, Bacteroidetes e Planctomicetes foram os quatro filos mais abundantes e ocorreram em todas as amostras. Adicionalmente, os tapetes eram compostos por bactérias potencialmente produtoras de toxinas, incluindo os gêneros de cianobacterias Blennothrix, Hormoscilla, e as espécies de proteobacterias Vibrio harveyi e Vibrio neptunius. Estas descobertas melhoram a nossa compreensão da ecologia dos tapetes de cianobacterias, o que servirá de suporte para os esforços de conservação focados na melhoria da saúde dos recifes de coral, especialmente diante das condições climáticas futuras, que prevêem o aumento da proliferação desses tapetes em detrimento do crescimento dos corais. No capítulo três, o ELSS é descrito em detalhe. O sistema consiste em 32 microcosmos independentes, cada um contendo sedimento de recife de coral, água do mar artificial e cinco organismos de recife, nomeadamente dois corais duros Montipora digitata e Montipora capricornis, um coral mole Sarcophyton glaucum, um zoantídeo Zoanthus sp. e uma esponja Chondrilla sp.. O sistema foi validado ao comparar as condições físico-químicas, a eficiência fotossintética dos corais e as comunidades bacterianas associadas ao ambiente e ao hospedeiro, com amostras dos microcosmos e de recifes naturais. Os resultados suportam a utilidade do ELSS para estudar biótopos de recifes de coral e as comunidades bacterianas associadas quando expostas a uma variedade de parâmetros ambientais. O ELSS desenvolvido foi posteriormente utilizado para testar a capacidade das HS para mitigar os efeitos adversos da temperatura elevada e da radiação UVB na atividade fotossintética dos corais, bem como nas comunidades bacterianas associadas ao ambiente e ao hospedeiro. A atividade fotossintética foi estimada medindo a fluorescência da clorofila dos corais, e as comunidades bacterianas foram estudadas através de sequenciação de alto rendimento (HTS) do gene 16S rRNA. Os resultados estão descritos nos capítulos quatro, cinco e seis e indicam que os corais em microcosmos suplementados com HS mostram atividade fotossintética significativamente mais elevada do que os corais em microcosmos submetidos a temperatura elevada e radiação UVB. A suplementação de HS também influenciou significativamente a composição das comunidades bacterianas nos sedimentos, na água e as comunidades associadas aos hospedeiros. Os indivíduos de M. digitata, S. glaucum e Chondrilla sp. em microcosmos suplementados com HS continham comunidades bacterianas únicas enriquecidas com grupos de bactérias potencialmente benéficas. No coral duro M. digitata, observamos um efeito interativo significativo de HS, UVB e temperatura, onde as comunidades bacterianas foram mais resilientes aos efeitos combinados de temperatura e radiação UVB em microcosmos suplementados com HS. Estes resultados têm repercussões significativas para a resiliência dos recifes diante do aumento dos fatores de stresse climático e destacam a importância da restauração das florestas costeiras, conhecidas como as principais fontes de substâncias húmicas em ambientes costeiros, para a proteção dos recifes de coral. |
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| dc.identifier.none.fl_str_mv | http://hdl.handle.net/10773/41901 |
| dc.language.none.fl_str_mv | eng |
| dc.rights.none.fl_str_mv | http://purl.org/coar/access_right/c_abf2 |
| dc.subject.none.fl_str_mv | Cyanobacteria Microbial mat 16S rRNA gene amplicon sequencing Bacterial communities Humic substances Terrestrial organic matter ENSO Climate change Montipora digitata Montipora capricornis Sarcophyton glaucum Chondrilla sp. |
| dc.title.fl_str_mv | Coral reef microbiota and the potential of humic substances to improve reef resilience |
| dc.type.none.fl_str_mv | http://purl.org/coar/resource_type/c_db06 |
| description | Coral reef ecosystems are renowned for their biodiversity and for their socioeconomic and ecological significance. In recent decades, however, the ecological balance within coral reefs has been disrupted leading to large-scale loss of coral reef habitat. El Niño Southern Oscillation (ENSO)-induced elevated temperatures and intense UVB radiation have resulted in global coral bleaching events. Meanwhile, large-scale urbanisation of coastal areas has further degraded reef ecosystems at local scales by increasing the inflow of nutrients and pollutants, and favoring the proliferation of benthic cyanobacterial mats over corals. To effectively protect and restore coral reefs, it is crucial to improve our understanding of these emerging microbial colonizers. Additionally, it is of paramount importance to identify local factors, which influence coral reef microbial communities and reef resilience. Previous observational studies have suggested that terrestrially-derived compounds, particularly humic substances (HS), can protect coral reefs from thermal stress. However, no study has, until now, systematically tested this hypothesis. This thesis addresses this gap by investigating 1) the diversity, distribution and biofouling activity of benthic cyanobacterial mats, 2) the suitability of an experimental life support system (ELLS) to study coral reef microbial communities under controlled conditions, 3) the effects of terrestriallyderived HS on coral reef microbial communities and 4) the potential of HS in augmenting coral reef resilience to elevated temperatures and UVB radiation. The goals were achieved by employing a comprehensive approach that combined field surveys, the development and subsequent utilization of an experimental life support system (ELSS), and chemical and microbial community analyses. Field surveys were performed to document and sample benthic cyanobacterial mats at reefs surrounding the island of Koh Tao (Gulf of Thailand). To obtain information on the bacterial community composition, samples were analysed using 16S rRNA gene high-throughput sequencing (HTS). The results of this study are discussed in chapter two and showed that mat colour (morphotype), substrate type and geographic location only explained a small part of the total variation in bacterial composition. Proteobacteria, Cyanobacteria, Bacteroidetes and Planctomycetes were the four most abundant phyla and occurred in all samples. Mats, moreover, were composed of potentially toxin producing bacteria, including the cyanobacterial genera Blennothrix, Hormoscilla, and the related proteobacterial species Vibrio harveyi and Vibrio neptunius. These findings improved our understanding of cyanobacterial mat ecology, which will help to guide conservation efforts aimed at improving coral reef health, especially in the light of future climate conditions which have been predicted to enhance mat proliferation at the expense of coral growth. In chapter three, the ELSS is described in detail. The system consisted of 32 independent microcosms, each containing coral reef sediment, artificial seawater, and five reef organisms. These included two hard corals Montipora digitata and Montipora capricornis, a soft coral Sarcophyton glaucum, a zoanthid Zoanthus sp., and a sponge Chondrilla sp.. The system was validated by comparing physiochemical conditions, coral photosynthetic efficiency and both environmental and host-associated bacterial communities sampled in microcosms and natural reef sites. The results supported the suitability of the ELSS to study coral reef biotopes and their associated bacterial communities exposed to a suite of environmental parameters. The developed ELSS was subsequently used to test to what extent HS are able to mitigate the adverse effects of elevated temperature and UVB radiation on coral photosynthetic activity, and environmental and host-associated bacterial communities. Photosynthetic activity was estimated by measuring the chlorophyll fluorescence of the corals and bacterial communities were studied using 16S rRNA gene HTS analysis. The results are described in chapters four, five and six and indicate that corals in HS-supplemented microcosms had significantly higher photosynthetic activities than those in microcosms subjected to elevated temperature and UVB radiation. HS supplementation, furthermore, significantly influenced the composition of sediment, water and host-associated bacterial communities. Individuals of M. digitata, S. glaucum and Chondrilla sp. in HS supplemented microcosms contained unique bacterial communities enriched with groups of potentially beneficial bacteria. In the hard coral M. digitata, we observed a significant interactive effect of HS, UVB, and temperature, whereby bacterial communities were more resilient to the combined effects of temperature and UVB radiation in microcosms supplemented with HS. These findings have significant repercussions for reef resilience in the face of increasing climate-induced stressors and highlight the importance of restoring coastal forests, known as the main sources of HS in coastal environments, to protect coral reefs. |
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| spelling | pt_PTCoral reef ecosystems are renowned for their biodiversity and for their socioeconomic and ecological significance. In recent decades, however, the ecological balance within coral reefs has been disrupted leading to large-scale loss of coral reef habitat. El Niño Southern Oscillation (ENSO)-induced elevated temperatures and intense UVB radiation have resulted in global coral bleaching events. Meanwhile, large-scale urbanisation of coastal areas has further degraded reef ecosystems at local scales by increasing the inflow of nutrients and pollutants, and favoring the proliferation of benthic cyanobacterial mats over corals. To effectively protect and restore coral reefs, it is crucial to improve our understanding of these emerging microbial colonizers. Additionally, it is of paramount importance to identify local factors, which influence coral reef microbial communities and reef resilience. Previous observational studies have suggested that terrestrially-derived compounds, particularly humic substances (HS), can protect coral reefs from thermal stress. However, no study has, until now, systematically tested this hypothesis. This thesis addresses this gap by investigating 1) the diversity, distribution and biofouling activity of benthic cyanobacterial mats, 2) the suitability of an experimental life support system (ELLS) to study coral reef microbial communities under controlled conditions, 3) the effects of terrestriallyderived HS on coral reef microbial communities and 4) the potential of HS in augmenting coral reef resilience to elevated temperatures and UVB radiation. The goals were achieved by employing a comprehensive approach that combined field surveys, the development and subsequent utilization of an experimental life support system (ELSS), and chemical and microbial community analyses. Field surveys were performed to document and sample benthic cyanobacterial mats at reefs surrounding the island of Koh Tao (Gulf of Thailand). To obtain information on the bacterial community composition, samples were analysed using 16S rRNA gene high-throughput sequencing (HTS). The results of this study are discussed in chapter two and showed that mat colour (morphotype), substrate type and geographic location only explained a small part of the total variation in bacterial composition. Proteobacteria, Cyanobacteria, Bacteroidetes and Planctomycetes were the four most abundant phyla and occurred in all samples. Mats, moreover, were composed of potentially toxin producing bacteria, including the cyanobacterial genera Blennothrix, Hormoscilla, and the related proteobacterial species Vibrio harveyi and Vibrio neptunius. These findings improved our understanding of cyanobacterial mat ecology, which will help to guide conservation efforts aimed at improving coral reef health, especially in the light of future climate conditions which have been predicted to enhance mat proliferation at the expense of coral growth. In chapter three, the ELSS is described in detail. The system consisted of 32 independent microcosms, each containing coral reef sediment, artificial seawater, and five reef organisms. These included two hard corals Montipora digitata and Montipora capricornis, a soft coral Sarcophyton glaucum, a zoanthid Zoanthus sp., and a sponge Chondrilla sp.. The system was validated by comparing physiochemical conditions, coral photosynthetic efficiency and both environmental and host-associated bacterial communities sampled in microcosms and natural reef sites. The results supported the suitability of the ELSS to study coral reef biotopes and their associated bacterial communities exposed to a suite of environmental parameters. The developed ELSS was subsequently used to test to what extent HS are able to mitigate the adverse effects of elevated temperature and UVB radiation on coral photosynthetic activity, and environmental and host-associated bacterial communities. Photosynthetic activity was estimated by measuring the chlorophyll fluorescence of the corals and bacterial communities were studied using 16S rRNA gene HTS analysis. The results are described in chapters four, five and six and indicate that corals in HS-supplemented microcosms had significantly higher photosynthetic activities than those in microcosms subjected to elevated temperature and UVB radiation. HS supplementation, furthermore, significantly influenced the composition of sediment, water and host-associated bacterial communities. Individuals of M. digitata, S. glaucum and Chondrilla sp. in HS supplemented microcosms contained unique bacterial communities enriched with groups of potentially beneficial bacteria. In the hard coral M. digitata, we observed a significant interactive effect of HS, UVB, and temperature, whereby bacterial communities were more resilient to the combined effects of temperature and UVB radiation in microcosms supplemented with HS. These findings have significant repercussions for reef resilience in the face of increasing climate-induced stressors and highlight the importance of restoring coastal forests, known as the main sources of HS in coastal environments, to protect coral reefs.pt_PTOs ecossistemas de recifes de coral são conhecidos pela sua biodiversidade, importância socioeconômica e ecológica. No entanto, nas últimas décadas, a disrupção do equilíbrio ecológico nos recifes de coral resultaram em reduções consideráveis deste habitat. As temperaturas elevadas induzidas pelo ENSO e a intensa radiação UVB têm causado eventos globais de branqueamento de corais. Ao mesmo tempo, a urbanização em larga escala das áreas costeiras degradaram ainda mais os ecossistemas de recifes em escalas locais, aumentando o influxo de nutrientes e poluentes e favorecendo a proliferação de tapetes bênticos de cianobactérias sobre os corais. Para proteger e restaurar efetivamente os recifes de coral, é crucial aprofundar a nossa compreensão destes colonizadores microbianos emergentes. Além disso, é de extrema importância identificar fatores locais que influenciam as comunidades microbianas e a resiliência dos recifes de coral. Estudos observacionais anteriores sugerem que compostos derivados do solo, em especial as substâncias húmicas (HS), podem proteger os recifes de coral de stresse térmico. Ainda assim, até hoje, nenhum estudo testou sistematicamente essa hipótese. Esta tese aborda essa lacuna investigando 1) a diversidade, distribuição e atividade de bioincrustação de tapetes bênticos de cianobactérias, 2) a adequação de um sistema experimental de suporte de vida (ELSS) para estudar comunidades microbianas de recifes de coral em condições controladas, 3) os efeitos das HS derivadas do solo nas comunidades microbianas de recifes de coral e 4) o potencial das HS em aumentar a resiliência dos recifes de coral a temperaturas elevadas e radiação UVB. Os objetivos foram alcançados através de uma abordagem abrangente que combinou saídas de campo, o desenvolvimento e a subsequente utilização de um sistema experimental de suporte de vida e análises químicas e das comunidades microbianas. As saídas de campo foram realizadas para documentar e coletar amostras de tapetes bênticos de cianobacterias nos recifes ao redor da ilha de Koh Tao (Golfo da Tailândia). Para obter informações sobre a composição da comunidade bacteriana, as amostras foram analisadas com recurso a highthroughput sequencing (HTS) do gene 16S rRNA. Os resultados das saídas de campo são discutidos no capítulo dois e demonstram que a cor do tapete (morfotipo), tipo de substrato e localização geográfica explicam apenas uma pequena parte da variação total da composição bacteriana. Proteobacteria, Cianobacteria, Bacteroidetes e Planctomicetes foram os quatro filos mais abundantes e ocorreram em todas as amostras. Adicionalmente, os tapetes eram compostos por bactérias potencialmente produtoras de toxinas, incluindo os gêneros de cianobacterias Blennothrix, Hormoscilla, e as espécies de proteobacterias Vibrio harveyi e Vibrio neptunius. Estas descobertas melhoram a nossa compreensão da ecologia dos tapetes de cianobacterias, o que servirá de suporte para os esforços de conservação focados na melhoria da saúde dos recifes de coral, especialmente diante das condições climáticas futuras, que prevêem o aumento da proliferação desses tapetes em detrimento do crescimento dos corais. No capítulo três, o ELSS é descrito em detalhe. O sistema consiste em 32 microcosmos independentes, cada um contendo sedimento de recife de coral, água do mar artificial e cinco organismos de recife, nomeadamente dois corais duros Montipora digitata e Montipora capricornis, um coral mole Sarcophyton glaucum, um zoantídeo Zoanthus sp. e uma esponja Chondrilla sp.. O sistema foi validado ao comparar as condições físico-químicas, a eficiência fotossintética dos corais e as comunidades bacterianas associadas ao ambiente e ao hospedeiro, com amostras dos microcosmos e de recifes naturais. Os resultados suportam a utilidade do ELSS para estudar biótopos de recifes de coral e as comunidades bacterianas associadas quando expostas a uma variedade de parâmetros ambientais. O ELSS desenvolvido foi posteriormente utilizado para testar a capacidade das HS para mitigar os efeitos adversos da temperatura elevada e da radiação UVB na atividade fotossintética dos corais, bem como nas comunidades bacterianas associadas ao ambiente e ao hospedeiro. A atividade fotossintética foi estimada medindo a fluorescência da clorofila dos corais, e as comunidades bacterianas foram estudadas através de sequenciação de alto rendimento (HTS) do gene 16S rRNA. Os resultados estão descritos nos capítulos quatro, cinco e seis e indicam que os corais em microcosmos suplementados com HS mostram atividade fotossintética significativamente mais elevada do que os corais em microcosmos submetidos a temperatura elevada e radiação UVB. A suplementação de HS também influenciou significativamente a composição das comunidades bacterianas nos sedimentos, na água e as comunidades associadas aos hospedeiros. Os indivíduos de M. digitata, S. glaucum e Chondrilla sp. em microcosmos suplementados com HS continham comunidades bacterianas únicas enriquecidas com grupos de bactérias potencialmente benéficas. No coral duro M. digitata, observamos um efeito interativo significativo de HS, UVB e temperatura, onde as comunidades bacterianas foram mais resilientes aos efeitos combinados de temperatura e radiação UVB em microcosmos suplementados com HS. Estes resultados têm repercussões significativas para a resiliência dos recifes diante do aumento dos fatores de stresse climático e destacam a importância da restauração das florestas costeiras, conhecidas como as principais fontes de substâncias húmicas em ambientes costeiros, para a proteção dos recifes de coral.application/pdfapplication/pdfapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheetengpt_PTCoral 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research producthttp://purl.org/coar/resource_type/c_db06doctoral thesis |
| spellingShingle | Coral reef microbiota and the potential of humic substances to improve reef resilience Stuij, Tamara Maria Cyanobacteria Microbial mat 16S rRNA gene amplicon sequencing Bacterial communities Humic substances Terrestrial organic matter ENSO Climate change Montipora digitata Montipora capricornis Sarcophyton glaucum Chondrilla sp. |
| status | SINGLETON |
| subject.fl_str_mv | Cyanobacteria Microbial mat 16S rRNA gene amplicon sequencing Bacterial communities Humic substances Terrestrial organic matter ENSO Climate change Montipora digitata Montipora capricornis Sarcophyton glaucum Chondrilla sp. |
| title | Coral reef microbiota and the potential of humic substances to improve reef resilience |
| title_full | Coral reef microbiota and the potential of humic substances to improve reef resilience |
| title_fullStr | Coral reef microbiota and the potential of humic substances to improve reef resilience |
| title_full_unstemmed | Coral reef microbiota and the potential of humic substances to improve reef resilience |
| title_short | Coral reef microbiota and the potential of humic substances to improve reef resilience |
| title_sort | Coral reef microbiota and the potential of humic substances to improve reef resilience |
| topic | Cyanobacteria Microbial mat 16S rRNA gene amplicon sequencing Bacterial communities Humic substances Terrestrial organic matter ENSO Climate change Montipora digitata Montipora capricornis Sarcophyton glaucum Chondrilla sp. |
| topic_facet | Cyanobacteria Microbial mat 16S rRNA gene amplicon sequencing Bacterial communities Humic substances Terrestrial organic matter ENSO Climate change Montipora digitata Montipora capricornis Sarcophyton glaucum Chondrilla sp. |
| url | http://hdl.handle.net/10773/41901 |
| visible | 1 |