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Hamamoto K, Mizuyama M, Nishijima M, Maeda A, Gibu K, Poliseno A, Iguchi A, Reimer JD. Diversity, composition and potential roles of sedimentary microbial communities in different coastal substrates around subtropical Okinawa Island, Japan. ENVIRONMENTAL MICROBIOME 2024; 19:54. [PMID: 39080706 PMCID: PMC11290285 DOI: 10.1186/s40793-024-00594-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Accepted: 07/08/2024] [Indexed: 08/02/2024]
Abstract
BACKGROUND Marine benthic prokaryotic communities play crucial roles in material recycling within coastal environments, including coral reefs. Coastal sedimentary microbiomes are particularly important as potential reservoirs of symbiotic, beneficial, and pathogenic bacteria in coral reef environments, and therefore presumably play a core role in local ecosystem functioning. However, there is a lack of studies comparing different environments with multiple sites on the island scale, particularly studies focusing on prokaryotic communities, as previous investigations have focused mainly on a single site or on specific environmental conditions. In our study, we collected coastal sediments from seven sites around Okinawa Island, Japan, including three different benthic types; sandy bottoms, seagrass meadows, and hard substratum with living scleractinian corals. We then used metabarcoding to identify prokaryotic compositions and estimate enzymes encoded by genes to infer their functions. RESULTS The results showed that the three substrata had significantly different prokaryotic compositions. Seagrass meadow sites exhibited significantly higher prokaryotic alpha-diversity compared to sandy bottom sites. ANCOM analysis revealed that multiple bacterial orders were differentially abundant within each substratum. At coral reef sites, putative disease- and thermal stress-related opportunistic bacteria such as Rhodobacterales, Verrucomicrobiales, and Cytophagales were comparatively abundant, while seagrass meadow sites abundantly harbored Desulfobacterales, Steroidobacterales and Chromatiales, which are common bacterial orders in seagrass meadows. According to our gene-coded enzyme analyses the numbers of differentially abundant enzymes were highest in coral reef sites. Notably, superoxide dismutase, an important enzyme for anti-oxidative stress in coral tissue, was abundant at coral sites. Our results provide a list of prokaryotes to look into in each substrate, and further emphasize the importance of considering the microbiome, especially when focusing on environmental conservation. CONCLUSION Our findings prove that prokaryotic metabarcoding is capable of capturing compositional differences and the diversity of microbial communities in three different environments. Furthermore, several taxa were suggested to be differentially more abundant in specific environments, and gene-coded enzymic compositions also showed possible differences in ecological functions. Further study, in combination with field observations and temporal sampling, is key to achieving a better understanding of the interactions between the local microbiome and the surrounding benthic community.
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Affiliation(s)
- Kohei Hamamoto
- Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, 305-8567, Japan.
- Molecular Invertebrate Systematics and Ecology (MISE) Laboratory, Graduate School of Engineering and Science, University of the Ryukyus, Nishihara, Okinawa, 903-0213, Japan.
| | - Masaru Mizuyama
- Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, 305-8567, Japan
- Department of Health Informatics, Faculty of Human Health Sciences, Meio University, Nago, Okinawa, 905-8585, Japan
| | - Miyuki Nishijima
- Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, 305-8567, Japan
| | - Ayumi Maeda
- Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, Chiba, 277-8564, Japan
| | - Kodai Gibu
- Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, 305-8567, Japan
| | - Angelo Poliseno
- Molecular Invertebrate Systematics and Ecology (MISE) Laboratory, Graduate School of Engineering and Science, University of the Ryukyus, Nishihara, Okinawa, 903-0213, Japan
| | - Akira Iguchi
- Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, 305-8567, Japan.
- Research Laboratory on Environmentally-Conscious Developments and Technologies [E-code], National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, 305-8567, Japan.
| | - James Davis Reimer
- Molecular Invertebrate Systematics and Ecology (MISE) Laboratory, Graduate School of Engineering and Science, University of the Ryukyus, Nishihara, Okinawa, 903-0213, Japan
- Tropical Biosphere Research Center, University of the Ryukyus, Nishihara, Okinawa, 903-0213, Japan
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Brodersen KE, Mosshammer M, Bittner MJ, Hallstrøm S, Santner J, Riemann L, Kühl M. Seagrass-mediated rhizosphere redox gradients are linked with ammonium accumulation driven by diazotrophs. Microbiol Spectr 2024; 12:e0333523. [PMID: 38426746 PMCID: PMC10986515 DOI: 10.1128/spectrum.03335-23] [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: 09/11/2023] [Accepted: 01/24/2024] [Indexed: 03/02/2024] Open
Abstract
Seagrasses can enhance nutrient mobilization in their rhizosphere via complex interactions with sediment redox conditions and microbial populations. Yet, limited knowledge exists on how seagrass-derived rhizosphere dynamics affect nitrogen cycling. Using optode and gel-sampler-based chemical imaging, we show that radial O2 loss (ROL) from rhizomes and roots leads to the formation of redox gradients around below-ground tissues of seagrass (Zostera marina), which are co-localized with regions of high ammonium concentrations in the rhizosphere. Combining such chemical imaging with fine-scale sampling for microbial community and gene expression analyses indicated that multiple biogeochemical pathways and microbial players can lead to high ammonium concentration within the oxidized regions of the seagrass rhizosphere. Symbiotic N2-fixing bacteria (Bradyrhizobium) were particularly abundant and expressed the diazotroph functional marker gene nifH in Z. marina rhizosphere areas with high ammonium concentrations. Such an association between Z. marina and Bradyrhizobium can facilitate ammonium mobilization, the preferred nitrogen source for seagrasses, enhancing seagrass productivity within nitrogen-limited environments. ROL also caused strong gradients of sulfide at anoxic/oxic interfaces in rhizosphere areas, where we found enhanced nifH transcription by sulfate-reducing bacteria. Furthermore, we found a high abundance of methylotrophic and sulfide-oxidizing bacteria in rhizosphere areas, where O2 was released from seagrass rhizomes and roots. These bacteria could play a beneficial role for the plants in terms of their methane and sulfide oxidation, as well as their formation of growth factors and phytohormones. ROL from below-ground tissues of seagrass, thus, seems crucial for ammonium production in the rhizosphere via stimulation of multiple diazotrophic associations. IMPORTANCE Seagrasses are important marine habitats providing several ecosystem services in coastal waters worldwide, such as enhancing marine biodiversity and mitigating climate change through efficient carbon sequestration. Notably, the fitness of seagrasses is affected by plant-microbe interactions. However, these microscale interactions are challenging to study and large knowledge gaps prevail. Our study shows that redox microgradients in the rhizosphere of seagrass select for a unique microbial community that can enhance the ammonium availability for seagrass. We provide first experimental evidence that Rhizobia, including the symbiotic N2-fixing bacteria Bradyrhizobium, can contribute to the bacterial ammonium production in the seagrass rhizosphere. The release of O2 from rhizomes and roots also caused gradients of sulfide in rhizosphere areas with enhanced nifH transcription by sulfate-reducing bacteria. O2 release from seagrass root systems thus seems crucial for ammonium production in the rhizosphere via stimulation of multiple diazotrophic associations.
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Affiliation(s)
| | - Maria Mosshammer
- Marine Biological Section, Department of Biology, University of Copenhagen, Helsingør, Denmark
| | - Meriel J. Bittner
- Marine Biological Section, Department of Biology, University of Copenhagen, Helsingør, Denmark
| | - Søren Hallstrøm
- Marine Biological Section, Department of Biology, University of Copenhagen, Helsingør, Denmark
| | - Jakob Santner
- Department of Crop Sciences, Institute of Agronomy, University of Natural Resources and Life Sciences Vienna, Tulln an der Donau, Austria
| | - Lasse Riemann
- Marine Biological Section, Department of Biology, University of Copenhagen, Helsingør, Denmark
| | - Michael Kühl
- Marine Biological Section, Department of Biology, University of Copenhagen, Helsingør, Denmark
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Sun H, Wang T, Liu S, Tang X, Sun J, Liu X, Zhao Y, Shen P, Zhang Y. Novel insights into the rhizosphere and seawater microbiome of Zostera marina in diverse mariculture zones. MICROBIOME 2024; 12:27. [PMID: 38350953 PMCID: PMC10865565 DOI: 10.1186/s40168-024-01759-3] [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: 08/25/2023] [Accepted: 01/07/2024] [Indexed: 02/15/2024]
Abstract
BACKGROUND Seagrasses offer various ecosystem services and possess high levels of primary productivity. However, the development of mariculture has affected the homeostasis of seagrass meadow ecosystems. Plant-microbiome associations are essential for seagrasses health, but little is known about the role of environmental microbiomes and how they affect seagrass in a mariculture environment. In this study, we investigated the influence of mariculture on the rhizosphere and seawater microbiome surrounding Zostera marina and focused on the bacterial, eukaryotic, and fungal components in the composition, diversity, metabolism, and responses to mariculture-related environmental factors. RESULTS Significant differences in the composition, richness, diversity, and internal relations of the bacterial community between the seawater and rhizosphere sediment surrounding Z. marina were observed, while differences in the eukaryotic and fungal communities were less significant. More complex bacterial and fungal co-occurrence networks were found in the seawater and rhizosphere sediment of the Saccharina japonica (SJ) and sea cucumber (SC) culture zones. The seawater in the SJ zone had higher levels of dissimilatory and assimilatory nitrate reduction, denitrification, and nitrogen fixation processes than the other three zones. The assimilatory sulfate reduction enzymes were higher in the rhizosphere sediments of the SJ zone than in the other three zones. Tetracycline, sulfonamide, and diaminopyrimidine resistance genes were enriched in the mariculture SJ and SC zones. CONCLUSIONS Our findings might contribute to a better understanding of the effects of mariculture on the seagrass and the meadow ecosystems and thus revealing their potential operating mechanisms. These insights may serve to raise awareness of the effects of human activities on natural ecosystems, regulation of antibiotic usage, and environmental restoration. Video Abstract.
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Affiliation(s)
- Hao Sun
- School of Ocean, Yantai University, Yantai, 264005, China
| | - Tianyu Wang
- School of Ocean, Yantai University, Yantai, 264005, China
| | - Shuai Liu
- School of Ocean, Yantai University, Yantai, 264005, China
| | - Xiaoyu Tang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Guangzhou, 510301, China
| | - Jie Sun
- Fisheries College, Ocean University of China, Qingdao, 266003, China
| | - Xuerui Liu
- School of Ocean, Yantai University, Yantai, 264005, China
| | - Ye Zhao
- School of Ocean, Yantai University, Yantai, 264005, China
| | - Pingping Shen
- School of Ocean, Yantai University, Yantai, 264005, China
| | - Yanying Zhang
- School of Ocean, Yantai University, Yantai, 264005, China.
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Tasdemir D, Scarpato S, Utermann-Thüsing C, Jensen T, Blümel M, Wenzel-Storjohann A, Welsch C, Echelmeyer VA. Epiphytic and endophytic microbiome of the seagrass Zostera marina: Do they contribute to pathogen reduction in seawater? THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 908:168422. [PMID: 37956849 DOI: 10.1016/j.scitotenv.2023.168422] [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: 08/18/2023] [Revised: 10/27/2023] [Accepted: 11/06/2023] [Indexed: 11/15/2023]
Abstract
Seagrass meadows provide crucial ecosystem services for coastal environments and were shown to reduce the abundance of waterborne pathogens linked to infections in humans and marine organisms in their vicinity. Among potential drivers, seagrass phenolics released into seawater have been linked to pathogen suppression, but the potential involvement of the seagrass microbiome has not been investigated. We hypothesized that the microbiome of the eelgrass Zostera marina, especially the leaf epiphytes that are at direct interface between the seagrass host and the surrounding seawater, inhibit waterborne pathogens thereby contributing to their removal. Using a culture-dependent approach, we isolated 88 bacteria and fungi associated with the surfaces and inner tissues of the eelgrass leaves (healthy and decaying) and the roots. We assessed the antibiotic activity of microbial extracts against a large panel of common aquatic, human (fecal) and plant pathogens, and mined the metabolome of the most active extracts. The healthy leaf epibiotic bacteria, particularly Streptomyces sp. strain 131, displayed broad-spectrum antibiotic activity superior to some control drugs. Gram-negative bacteria abundant on healthy leaf surfaces, and few endosphere-associated bacteria and fungi also displayed remarkable activities. UPLC-MS/MS-based untargeted metabolomics analyses showed rich specialized metabolite repertoires with low annotation rates, indicating the presence of many undescribed antimicrobials in the extracts. This study contributes to our understanding on microbial and chemical ecology of seagrasses, implying potential involvement of the seagrass microbiome in suppression of pathogens in seawater. Such effect is beneficial for the health of ocean and human, especially in the context of climate change that is expected to exacerbate all infectious diseases. It may also assist future seagrass conservation and management strategies.
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Affiliation(s)
- Deniz Tasdemir
- GEOMAR Centre for Marine Biotechnology (GEOMAR-Biotech), Research Unit Marine Natural Products Chemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel 24106, Germany; Faculty of Mathematics and Natural Sciences, Kiel University, Kiel 24118, Germany.
| | - Silvia Scarpato
- GEOMAR Centre for Marine Biotechnology (GEOMAR-Biotech), Research Unit Marine Natural Products Chemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel 24106, Germany
| | - Caroline Utermann-Thüsing
- GEOMAR Centre for Marine Biotechnology (GEOMAR-Biotech), Research Unit Marine Natural Products Chemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel 24106, Germany
| | - Timo Jensen
- GEOMAR Centre for Marine Biotechnology (GEOMAR-Biotech), Research Unit Marine Natural Products Chemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel 24106, Germany
| | - Martina Blümel
- GEOMAR Centre for Marine Biotechnology (GEOMAR-Biotech), Research Unit Marine Natural Products Chemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel 24106, Germany
| | - Arlette Wenzel-Storjohann
- GEOMAR Centre for Marine Biotechnology (GEOMAR-Biotech), Research Unit Marine Natural Products Chemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel 24106, Germany
| | - Claudia Welsch
- GEOMAR Centre for Marine Biotechnology (GEOMAR-Biotech), Research Unit Marine Natural Products Chemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel 24106, Germany
| | - Vivien Anne Echelmeyer
- GEOMAR Centre for Marine Biotechnology (GEOMAR-Biotech), Research Unit Marine Natural Products Chemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel 24106, Germany
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Zhou W, Ling J, Shen X, Xu Z, Yang Q, Yue W, Liu H, Suo A, Dong J. Inoculation with plant growth-promoting rhizobacteria improves seagrass Thalassia hemprichii photosynthesis performance and shifts rhizosphere microbiome. MARINE ENVIRONMENTAL RESEARCH 2024; 193:106260. [PMID: 38061311 DOI: 10.1016/j.marenvres.2023.106260] [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: 08/18/2023] [Revised: 10/31/2023] [Accepted: 11/09/2023] [Indexed: 01/02/2024]
Abstract
Plant growth-promoting rhizobacteria (PGPR) inoculation is a crucial strategy for maintaining the sustainability of agriculture and presents a promising solution for seagrass ecological restoration in the face of disturbances. However, the possible roles and functions of PGPRs in the seagrass rhizosphere remain unclear. Here, we isolated rhizosphere bacterial strains from both reef and coastal regions and screened two PGPR isolates regarding their in vivo functional traits. Subsequently, we conducted microcosm experiments to elucidate how PGPR inoculation affected seagrass photosynthesis and shape within each rhizosphere microbiome. Both screened PGPR strains, Raoultella terrigena NXT28 and Bacillus aryabhattai XT37, excelled at expressing a specific subset of plant-beneficial functions and increased the photosynthetic rates of the seagrass host. PGPR inoculation not only decreased the abundance of sulfur-cycling bacteria, it also improved the abundance of putative iron-cycling bacteria in the seagrass rhizosphere. Strain XT37 successfully colonized the seagrass rhizosphere and displayed a leading role in microbial network structure. As a nitrogen-fixing bacteria, NXT28 showed potential to change the microbial nitrogen cycle with denitrification in the rhizosphere and alter dissimilatory and assimilatory nitrate reduction in bulk sediment. These findings have implications for the development of eco-friendly strategies aimed at exploiting microbial communities to confer sulfide tolerance in coastal seagrass ecosystem.
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Affiliation(s)
- Weiguo Zhou
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Ocean Eco-Environmental Engineering, Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya, 572000, China
| | - Juan Ling
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Ocean Eco-Environmental Engineering, Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya, 572000, China; Guangdong Provincial Observation and Research Station for Coastal Upwelling Ecosystem, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Shantou, 515041, China
| | - Xiaomei Shen
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou, 510006, China
| | - Zhimeng Xu
- Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory, The Hong Kong University of Science and Technology, Kowloon, Hong Kong SAR, China
| | - Qingsong Yang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Ocean Eco-Environmental Engineering, Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya, 572000, China; Guangdong Provincial Observation and Research Station for Coastal Upwelling Ecosystem, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Shantou, 515041, China
| | - Weizhong Yue
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Ocean Eco-Environmental Engineering, Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya, 572000, China
| | - Hongbin Liu
- Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory, The Hong Kong University of Science and Technology, Kowloon, Hong Kong SAR, China
| | - Anning Suo
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Ocean Eco-Environmental Engineering, Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya, 572000, China.
| | - Junde Dong
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Ocean Eco-Environmental Engineering, Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya, 572000, China; Guangdong Provincial Observation and Research Station for Coastal Upwelling Ecosystem, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Shantou, 515041, China.
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Rotini A, Conte C, Winters G, Vasquez MI, Migliore L. Undisturbed Posidonia oceanica meadows maintain the epiphytic bacterial community in different environments. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:95464-95474. [PMID: 37548791 PMCID: PMC10482771 DOI: 10.1007/s11356-023-28968-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 07/20/2023] [Indexed: 08/08/2023]
Abstract
Seagrasses harbour different and rich epiphytic bacterial communities. These microbes may establish intimate and symbiotic relationships with the seagrass plants and change according to host species, environmental conditions, and/or ecophysiological status of their seagrass host. Although Posidonia oceanica is one of the most studied seagrasses in the world, and bacteria associated with seagrasses have been studied for over a decade, P. oceanica's microbiome remains hitherto little explored. Here, we applied 16S rRNA amplicon sequencing to explore the microbiome associated with the leaves of P. oceanica growing in two geomorphologically different meadows (e.g. depth, substrate, and turbidity) within the Limassol Bay (Cyprus). The morphometric (leaf area, meadow density) and biochemical (pigments, total phenols) descriptors highlighted the healthy conditions of both meadows. The leaf-associated bacterial communities showed similar structure and composition in the two sites; core microbiota members were dominated by bacteria belonging to the Thalassospiraceae, Microtrichaceae, Enterobacteriaceae, Saprospiraceae, and Hyphomonadaceae families. This analogy, even under different geomorphological conditions, suggest that in the absence of disturbances, P. oceanica maintains characteristic-associated bacterial communities. This study provides a baseline for the knowledge of the P. oceanica microbiome and further supports its use as a putative seagrass descriptor.
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Affiliation(s)
- Alice Rotini
- ISPRA Istituto Superiore per la Protezione e la Ricerca Ambientale, Via Vitaliano Brancati, 48, 00144, Rome, Italy
| | - Chiara Conte
- Department of Biology, Laboratory of Ecology and Ecotoxicology, University of Rome Tor Vergata, 00133, Rome, Italy
| | - Gidon Winters
- Dead Sea and Arava Science Center (DSASC), Masada National Park, 86910, Masada, Israel
- Eilat Campus, Ben-Gurion University of the Negev, Hatmarim Blv., 8855630, Eilat, Israel
| | - Marlen I Vasquez
- Department of Chemical Engineering, Cyprus University of Technology, 30 Archbishop Kyprianos Str.t, 3036, Limassol, Cyprus
- European University of Technology, 30 Archbishop Kyprianos Str.t, 3036, Limassol, Cyprus
| | - Luciana Migliore
- Department of Biology, Laboratory of Ecology and Ecotoxicology, University of Rome Tor Vergata, 00133, Rome, Italy.
- eCampus University, Via Isimbardi 10, 22060, Novedrate, CO, Italy.
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Conte C, Apostolaki ET, Vizzini S, Migliore L. A Tight Interaction between the Native Seagrass Cymodocea nodosa and the Exotic Halophila stipulacea in the Aegean Sea Highlights Seagrass Holobiont Variations. PLANTS (BASEL, SWITZERLAND) 2023; 12:350. [PMID: 36679063 PMCID: PMC9863530 DOI: 10.3390/plants12020350] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 01/03/2023] [Accepted: 01/05/2023] [Indexed: 06/17/2023]
Abstract
Seagrasses harbour bacterial communities with which they constitute a functional unit called holobiont that responds as a whole to environmental changes. Epiphytic bacterial communities rapidly respond to both biotic and abiotic factors, potentially contributing to the host fitness. The Lessepsian migrant Halophila stipulacea has a high phenotypical plasticity and harbours a highly diverse epiphytic bacterial community, which could support its invasiveness in the Mediterranean Sea. The current study aimed to evaluate the Halophila/Cymodocea competition in the Aegean Sea by analysing each of the two seagrasses in a meadow zone where these intermingled, as well as in their monospecific zones, at two depths. Differences in holobionts were evaluated using seagrass descriptors (morphometric, biochemical, elemental, and isotopic composition) to assess host changes, and 16S rRNA gene to identify bacterial community structure and composition. An Indicator Species Index was used to identify bacteria significantly associated with each host. In mixed meadows, native C. nodosa was shown to be affected by the presence of exotic H. stipulacea, in terms of both plant descriptors and bacterial communities, while H. stipulacea responded only to environmental factors rather than C. nodosa proximity. This study provided evidence of the competitive advantage of H. stipulacea on C. nodosa in the Aegean Sea and suggests the possible use of associated bacterial communities as an ecological seagrass descriptor.
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Affiliation(s)
- Chiara Conte
- PhD Program in Evolutionary Biology and Ecology, University of Rome Tor Vergata, 00133 Rome, Italy
- Laboratory of Ecology and Ecotoxicology, Department of Biology, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Eugenia T. Apostolaki
- Institute of Oceanography, Hellenic Centre for Marine Research, P.O. Box 2214, 71003 Heraklion, Crete, Greece
| | - Salvatrice Vizzini
- Department of Earth and Marine Sciences, University of Palermo, Via Archirafi 18, 90123 Palermo, Italy
- CoNISMa, National Interuniversity Consortium for Marine Sciences, Piazzale Flaminio 9, 00196 Roma, Italy
| | - Luciana Migliore
- Laboratory of Ecology and Ecotoxicology, Department of Biology, University of Rome Tor Vergata, 00133 Rome, Italy
- eCampus University, Via Isimbardi 10, 22060 Novedrate (CO), Italy
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Shu Q, Xia D, Ma Y, Zhang Y, Luo T, Ma J, Liu F, Yan S, Liu D. Response of physiological characteristics of ecological restoration plants to substrate cement content under exogenous arbuscular mycorrhizal fungal inoculation. FRONTIERS IN PLANT SCIENCE 2022; 13:1028553. [PMID: 36507450 PMCID: PMC9728102 DOI: 10.3389/fpls.2022.1028553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 11/03/2022] [Indexed: 06/17/2023]
Abstract
INTRODUCTION In order to solve the inhibition of alkaline environment on plants growth at the initial stage of Eco-restoration of vegetation concrete technology, introducing AMF into vegetation concrete substrate is an effective solution. METHODS In this study, Glomus mosseae (GM), Glomus intraradices (GI) and a mixture of two AMF (MI) were used as exogenous inoculation agents. Festuca elata and Cassia glauca were selected as host plants to explore the relationship between the physiological characteristics of plants and the content of substrate cement under exogenous inoculation of AMF. RESULTS The experiment showed that, for festuca elata, the maximum mycorrhizal infection rates of inoculation with GM, MI were when the cement contents ranged 5-8% and that of GI inoculation was with the cement contents ranging 5-10%. Adversely, for Cassia glauca, substrate cement content had little effect on the root system with the exogenous inoculation of AMF. Compared with CK, the effects of AMF inoculation on the physiological characteristics of the two plants were different. When the cement content was the highest (10% and 8% respectively), AMF could significantly increase(p<0.05) the intercellular CO2 concentration (Ci) of Festuca elata. Moreover, for both plants, single inoculation was more effective than mixed inoculation. When the cement content was relatively low, the physiological characteristics of Cassia glauca were promoted more obviously by the inoculation of GI. At higher cement content level, inoculation of GM had a better effect on the physiological characteristics of the two plants. CONCLUSION The results suggest that single inoculation of GM should be selected to promote the growth of Festuca elata and Cassia glauca in higher alkaline environment.
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Affiliation(s)
- Qian Shu
- College of Biological & Pharmaceutical Sciences, China Three Gorges University, Yichang, China
- Hubei Provincial Engineering Research Center of Slope Habitat Construction Technique Using Cement-based Materials, China Three Gorges University, Key Laboratory of Mountain Hazards and Surface Processes Chinese, Yichang, China
| | - Dong Xia
- College of Biological & Pharmaceutical Sciences, China Three Gorges University, Yichang, China
- Hubei Provincial Engineering Research Center of Slope Habitat Construction Technique Using Cement-based Materials, China Three Gorges University, Key Laboratory of Mountain Hazards and Surface Processes Chinese, Yichang, China
- College of Hydraulic & Environmental Engineering, China Three Gorges University, Yichang, China
| | - Yueyang Ma
- Hubei Provincial Engineering Research Center of Slope Habitat Construction Technique Using Cement-based Materials, China Three Gorges University, Key Laboratory of Mountain Hazards and Surface Processes Chinese, Yichang, China
- College of Civil Engineering & Architecture, China Three Gorges University, Yichang, China
| | - Yang Zhang
- College of Biological & Pharmaceutical Sciences, China Three Gorges University, Yichang, China
- Hubei Provincial Engineering Research Center of Slope Habitat Construction Technique Using Cement-based Materials, China Three Gorges University, Key Laboratory of Mountain Hazards and Surface Processes Chinese, Yichang, China
| | - Ting Luo
- Hubei Provincial Engineering Research Center of Slope Habitat Construction Technique Using Cement-based Materials, China Three Gorges University, Key Laboratory of Mountain Hazards and Surface Processes Chinese, Yichang, China
- College of Civil Engineering & Architecture, China Three Gorges University, Yichang, China
| | - Jiaxin Ma
- College of Biological & Pharmaceutical Sciences, China Three Gorges University, Yichang, China
- Hubei Provincial Engineering Research Center of Slope Habitat Construction Technique Using Cement-based Materials, China Three Gorges University, Key Laboratory of Mountain Hazards and Surface Processes Chinese, Yichang, China
| | - Fang Liu
- Hubei Provincial Engineering Research Center of Slope Habitat Construction Technique Using Cement-based Materials, China Three Gorges University, Key Laboratory of Mountain Hazards and Surface Processes Chinese, Yichang, China
- College of Hydraulic & Environmental Engineering, China Three Gorges University, Yichang, China
| | - Shuxing Yan
- Hubei Provincial Engineering Research Center of Slope Habitat Construction Technique Using Cement-based Materials, China Three Gorges University, Key Laboratory of Mountain Hazards and Surface Processes Chinese, Yichang, China
- College of Hydraulic & Environmental Engineering, China Three Gorges University, Yichang, China
| | - Daxiang Liu
- Hubei Provincial Engineering Research Center of Slope Habitat Construction Technique Using Cement-based Materials, China Three Gorges University, Key Laboratory of Mountain Hazards and Surface Processes Chinese, Yichang, China
- College of Civil Engineering & Architecture, China Three Gorges University, Yichang, China
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9
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Abstract
Coastal marine macrophytes exhibit some of the highest rates of primary productivity in the world. They have been found to host a diverse set of microbes, many of which may impact the biology of their hosts through metabolisms that are unique to microbial taxa. Here, we characterized the metabolic functions of macrophyte-associated microbial communities using metagenomes collected from 2 species of kelp (Laminaria setchellii and Nereocystis luetkeana) and 3 marine angiosperms (Phyllospadix scouleri, P. serrulatus, and Zostera marina), including the rhizomes of two surfgrass species (Phyllospadix spp.), the seagrass Zostera marina, and the sediments surrounding P. scouleri and Z. marina. Using metagenomic sequencing, we describe 63 metagenome-assembled genomes (MAGs) that potentially benefit from being associated with macrophytes and may contribute to macrophyte fitness through their metabolic activity. Host-associated metagenomes contained genes for the use of dissolved organic matter from hosts and vitamin (B1, B2, B7, B12) biosynthesis in addition to a range of nitrogen and sulfur metabolisms that recycle dissolved inorganic nutrients into forms more available to the host. The rhizosphere of surfgrass and seagrass contained genes for anaerobic microbial metabolisms, including nifH genes associated with nitrogen fixation, despite residing in a well-mixed and oxygenated environment. The range of oxygen environments engineered by macrophytes likely explains the diversity of both oxidizing and reducing microbial metabolisms and contributes to the functional capabilities of microbes and their influences on carbon and nitrogen cycling in nearshore ecosystems. IMPORTANCE Kelps, seagrasses, and surfgrasses are ecosystem engineers on rocky shorelines, where they show remarkably high levels of primary production. Through analysis of their associated microbial communities, we found a variety of microbial metabolisms that may benefit the host, including nitrogen metabolisms, sulfur oxidation, and the production of B vitamins. In turn, these microbes have the genetic capabilities to assimilate the dissolved organic compounds released by their macrophyte hosts. We describe a range of oxygen environments associated with surfgrass, including low-oxygen microhabitats in their rhizomes that host genes for nitrogen fixation. The tremendous productivity of coastal seaweeds and seagrasses is likely due in part to the activities of associated microbes, and an increased understanding of these associations is needed.
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10
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Mohapatra M, Manu S, Dash SP, Rastogi G. Seagrasses and local environment control the bacterial community structure and carbon substrate utilization in brackish sediments. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 314:115013. [PMID: 35447445 DOI: 10.1016/j.jenvman.2022.115013] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 03/16/2022] [Accepted: 04/02/2022] [Indexed: 06/14/2023]
Abstract
Seagrasses are complex benthic coastal ecosystems that play a crucial role in organic matter cycling and carbon sequestration. However, little is known about how seagrasses influence the structure and carbon utilization potential of benthic bacterial communities. This study examined the bacterial communities in monospecific and mixed meadows of seagrasses and compared with bulk (unvegetated) sediments from Chilika, a brackish water coastal lagoon of India. High-throughput sequencing of 16S rRNA genes revealed a vegetation effect in terms of differences in benthic bacterial community diversity, composition, and abundances in comparison with bulk sediments. Desulfobacterales, Chromatiales, Enterobacteriales, Clostridiales, Vibrionales, and Acidimicrobiales were major taxa that contributed to differences between seagrass and bulk sediments. Seagrasses supported ∼5.94 fold higher bacterial abundances than the bulk due to rich organic carbon stock in their sediments. Co-occurrence network demonstrated much stronger potential interactions and connectedness in seagrass bacterial communities compared to bulk. Chromatiales and Acidimicrobiales were identified as the top two keystone taxa in seagrass bacterial communities, whereas, Dehalococcoidales and Rhizobiales were in bulk communities. Seagrasses and local environmental factors, namely, water depth, water pH, sediment salinity, redox potential, total organic carbon, available nitrogen, sediment texture, sediment pH, and sediment core depth were the major drivers of benthic bacterial community composition. Carbon metabolic profiling revealed that heterotrophic bacteria in seagrass sediments were much more metabolically diverse and active than bulk. The utilization of carbon substrate guilds, namely, amino acids, amines, carboxylic acids, carbohydrates, polymers, and phenolic compounds was enhanced in seagrass sediments. Metabolic mapping predicted higher prevalence of sulfate-reducer and N2 fixation metabolic functions in seagrass sediments. Overall, this study showed that seagrasses control benthic bacterial community composition and diversity, enhance heterotrophic carbon substrate utilization, and play crucial roles in organic matter cycling including degradation of hydrocarbon and xenobiotics in coastal sediments.
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Affiliation(s)
- Madhusmita Mohapatra
- Wetland Research and Training Centre, Chilika Development Authority, Balugaon, 752030, Odisha, India
| | - Shivakumara Manu
- CSIR-Centre for Cellular and Molecular Biology, Hyderabad, 500048, India
| | - Stiti Prangya Dash
- Wetland Research and Training Centre, Chilika Development Authority, Balugaon, 752030, Odisha, India
| | - Gurdeep Rastogi
- Wetland Research and Training Centre, Chilika Development Authority, Balugaon, 752030, Odisha, India.
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11
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Szitenberg A, Beca-Carretero P, Azcárate-García T, Yergaliyev T, Alexander-Shani R, Winters G. Teasing apart the host-related, nutrient-related and temperature-related effects shaping the phenology and microbiome of the tropical seagrass Halophila stipulacea. ENVIRONMENTAL MICROBIOME 2022; 17:18. [PMID: 35428367 PMCID: PMC9013022 DOI: 10.1186/s40793-022-00412-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Accepted: 03/24/2022] [Indexed: 06/02/2023]
Abstract
BACKGROUND Halophila stipulacea seagrass meadows are an ecologically important and threatened component of the ecosystem in the Gulf of Aqaba. Recent studies have demonstrated correlated geographic patterns for leaf epiphytic community composition and leaf morphology, also coinciding with different levels of water turbidity and nutrient concentrations. Based on these observations, workers have suggested an environmental microbial fingerprint, which may reflect various environmental stress factors seagrasses have experienced, and may add a holobiont level of plasticity to seagrasses, assisting their acclimation to changing environments and through range expansion. However, it is difficult to tease apart environmental effects from host-diversity dependent effects, which have covaried in field studies, although this is required in order to establish that differences in microbial community compositions among sites are driven by environmental conditions rather than by features governed by the host. RESULTS In this study we carried out a mesocosm experiment, in which we studied the effects of warming and nutrient stress on the composition of epiphytic bacterial communities and on some phenological traits. We studied H. stipulacea collected from two different meadows in the Gulf of Aqaba, representing differences in the host and the environment alike. We found that the source site from which seagrasses were collected was the major factor governing seagrass phenology, although heat increased shoot mortality and nutrient loading delayed new shoot emergence. Bacterial diversity, however, mostly depended on the environmental conditions. The most prominent pattern was the increase in Rhodobacteraceae under nutrient stress without heat stress, along with an increase in Microtrichaceae. Together, the two taxa have the potential to maintain nitrate reduction followed by an anammox process, which can together buffer the increase in nutrient concentrations across the leaf surface. CONCLUSIONS Our results thus corroborate the existence of environmental microbial fingerprints, which are independent from the host diversity, and support the notion of a holobiont level plasticity, both important to understand and monitor H. stipulacea ecology under the changing climate.
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Affiliation(s)
- Amir Szitenberg
- Dead Sea and Arava Science Center, Dead Sea Branch, 8693500, Masada, Israel.
- Ben-Gurion University of the Negev, 8858537, Eilat, Israel.
| | - Pedro Beca-Carretero
- Department of Theoretical Ecology and Modelling, Leibniz Centre for Tropical Marine Research, Fahrenheitstrasse 6, 28359, Bremen, Germany
- Department of Oceanography, Instituto de Investigacións Mariñas (IIM-CSIC), Vigo, Spain
- Departamento de Biología, Área de Ecología, Facultad de Ciencias del Mar Y Ambientales, Universidad de Cádiz, 11510, Puerto Real, Cádiz, Spain
| | - Tomás Azcárate-García
- Department of Theoretical Ecology and Modelling, Leibniz Centre for Tropical Marine Research, Fahrenheitstrasse 6, 28359, Bremen, Germany
- Departamento de Biología, Área de Ecología, Facultad de Ciencias del Mar Y Ambientales, Universidad de Cádiz, 11510, Puerto Real, Cádiz, Spain
- Dead Sea and Arava Science Center, Central Arava Branch, 8682500, Sapir, Israel
| | - Timur Yergaliyev
- Dead Sea and Arava Science Center, Dead Sea Branch, 8693500, Masada, Israel
- Hohenheim Center for Livestock Microbiome Research (HoLMiR), Institute of Animal Science, University of Hohenheim, Stuttgart, Germany
| | | | - Gidon Winters
- Ben-Gurion University of the Negev, 8858537, Eilat, Israel
- Dead Sea and Arava Science Center, Central Arava Branch, 8682500, Sapir, Israel
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12
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Zhang X, Liu S, Jiang Z, Wu Y, Huang X. Gradient of microbial communities around seagrass roots was mediated by sediment grain size. Ecosphere 2022. [DOI: 10.1002/ecs2.3942] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Xia Zhang
- Key Laboratory of Tropical Marine Bio‐resources and Ecology South China Sea Institute of Oceanology, Chinese Academy of Sciences Guangzhou China
- Southern Marine Science and Engineering Guangdong Laboratory Guangzhou China
| | - Songlin Liu
- Key Laboratory of Tropical Marine Bio‐resources and Ecology South China Sea Institute of Oceanology, Chinese Academy of Sciences Guangzhou China
- Southern Marine Science and Engineering Guangdong Laboratory Guangzhou China
- Key Laboratory of Tropical Marine Biotechnology of Hainan Province Sanya Institute of Oceanology, SCSIO Sanya China
| | - Zhijian Jiang
- Key Laboratory of Tropical Marine Bio‐resources and Ecology South China Sea Institute of Oceanology, Chinese Academy of Sciences Guangzhou China
- Southern Marine Science and Engineering Guangdong Laboratory Guangzhou China
| | - Yunchao Wu
- Key Laboratory of Tropical Marine Bio‐resources and Ecology South China Sea Institute of Oceanology, Chinese Academy of Sciences Guangzhou China
- Southern Marine Science and Engineering Guangdong Laboratory Guangzhou China
| | - Xiaoping Huang
- Key Laboratory of Tropical Marine Bio‐resources and Ecology South China Sea Institute of Oceanology, Chinese Academy of Sciences Guangzhou China
- Southern Marine Science and Engineering Guangdong Laboratory Guangzhou China
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13
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Soonthornkalump S, Ow YX, Saewong C, Buapet P. Comparative study on anatomical traits and gas exchange responses due to belowground hypoxic stress and thermal stress in three tropical seagrasses. PeerJ 2022; 10:e12899. [PMID: 35186485 PMCID: PMC8840093 DOI: 10.7717/peerj.12899] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 01/17/2022] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND The ability to maintain sufficient oxygen levels in the belowground tissues and the rhizosphere is crucial for the growth and survival of seagrasses in habitats with highly reduced sediment. Such ability varies depending on plant anatomical features and environmental conditions. METHODS In the present study, we compared anatomical structures of roots, rhizomes and leaves of the tropical intertidal seagrasses, Cymodocea rotundata, Thalassia hemprichii and Halophila ovalis, followed by an investigation of their gas exchange both in the belowground and aboveground tissues and photosynthetic electron transport rates (ETR) in response to experimental manipulations of O2 level (normoxia and root hypoxia) and temperature (30 °C and 40 °C). RESULTS We found that C. rotundata and T. hemprichii displayed mostly comparable anatomical structures, whereas H. ovalis displayed various distinctive features, including leaf porosity, number and size of lacunae in roots and rhizomes and structure of radial O2 loss (ROL) barrier. H. ovalis also showed unique responses to root hypoxia and heat stress. Root hypoxia increased O2 release from belowground tissues and overall photosynthetic activity of H. ovalis but did not affect the other two seagrasses. More pronounced warming effects were detected in H. ovalis, measured as lower O2 release in the belowground tissues and overall photosynthetic capacity (O2 release and dissolved inorganic carbon uptake in the light and ETR). High temperature inhibited photosynthesis of C. rotundata and T. hemprichii but did not affect their O2 release in belowground tissues. Our data show that seagrasses inhabiting the same area respond differently to root hypoxia and temperature, possibly due to their differences in anatomical and physiological attributes. Halophila ovalis is highly dependent on photosynthesis and appears to be the most sensitive species with the highest tendency of O2 loss in hypoxic sediment. At the same time, its root oxidation capacity may be compromised under warming scenarios.
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Affiliation(s)
- Sutthinut Soonthornkalump
- Division of Biological Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla, Thailand,Coastal Oceanography and Climate Change Research Center, Prince of Songkla University, Hat Yai, Songkhla, Thailand
| | - Yan Xiang Ow
- St John’s Island National Marine Laboratory, Tropical Marine Science Institute, National University of Singapore, Singapore, Singapore
| | - Chanida Saewong
- Division of Biological Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla, Thailand,Coastal Oceanography and Climate Change Research Center, Prince of Songkla University, Hat Yai, Songkhla, Thailand
| | - Pimchanok Buapet
- Division of Biological Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla, Thailand,Coastal Oceanography and Climate Change Research Center, Prince of Songkla University, Hat Yai, Songkhla, Thailand
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14
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Ren L, Jensen K, Porada P, Mueller P. Biota-mediated carbon cycling-A synthesis of biotic-interaction controls on blue carbon. Ecol Lett 2022; 25:521-540. [PMID: 35006633 DOI: 10.1111/ele.13940] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 08/03/2021] [Accepted: 11/02/2021] [Indexed: 01/22/2023]
Abstract
Research into biotic interactions has been a core theme of ecology for over a century. However, despite the obvious role that biota play in the global carbon cycle, the effects of biotic interactions on carbon pools and fluxes are poorly understood. Here we develop a conceptual framework that illustrates the importance of biotic interactions in regulating carbon cycling based on a literature review and a quantitative synthesis by means of meta-analysis. Our study focuses on blue carbon ecosystems-vegetated coastal ecosystems that function as the most effective long-term CO2 sinks of the biosphere. We demonstrate that a multitude of mutualistic, competitive and consumer-resource interactions between plants, animals and microbiota exert strong effects on carbon cycling across various spatial scales ranging from the rhizosphere to the landscape scale. Climate change-sensitive abiotic factors modulate the strength of biotic-interaction effects on carbon fluxes, suggesting that the importance of biota-mediated carbon cycling will change under future climatic conditions. Strong effects of biotic interactions on carbon cycling imply that biosphere-climate feedbacks may not be sufficiently represented in current Earth system models. Inclusion of new functional groups in these models, and new approaches to simplify species interactions, may thus improve the predictions of biotic effects on the global climate.
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Affiliation(s)
- Linjing Ren
- Institute of Plant Science and Microbiology, Universität Hamburg, Hamburg, Germany.,State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, P. R. China
| | - Kai Jensen
- Institute of Plant Science and Microbiology, Universität Hamburg, Hamburg, Germany
| | - Philipp Porada
- Institute of Plant Science and Microbiology, Universität Hamburg, Hamburg, Germany
| | - Peter Mueller
- Institute of Plant Science and Microbiology, Universität Hamburg, Hamburg, Germany.,Smithsonian Environmental Research Center, Edgewater, Maryland, USA
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15
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Qin LZ, Suonan Z, Kim SH, Lee KS. Coastal Sediment Nutrient Enrichment Alters Seagrass Blue Carbon Sink Capacity. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:15466-15475. [PMID: 34698488 DOI: 10.1021/acs.est.1c03782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The seagrass ecosystem is among the most efficient natural carbon sinks that can contribute to climate change mitigation. However, little is known about the effects of coastal nutrient enrichment caused by anthropogenic activities and/or climate change on the capacity of the seagrass blue carbon sink. Our experimental manipulations of sediment nutrient enrichment shifted the blue carbon sink capabilities of seagrass meadows. Sediment nutrient enrichment significantly increased the nutrient content of seagrass litter, stimulating the decomposition of rhizome + root litter by ∼10% while retarding the decomposition of leaf litter by ∼5%. Sediment N + P enrichment increased seagrass growth and litter production, while enrichment of N or P alone did not. Organic carbon (Corg) stocks in the surface sediments (0-5 cm) were 34% higher than those in the control with N + P enrichment due to high litter production and the low decomposition rate of nutrient-enriched leaf litter. However, Corg stocks in the subsurface sediments (5-20 cm) did not increase with sediment nutrient enrichment, which is likely due to accelerated decomposition of rhizome + root litter. Our findings suggest that nutrient loading in coastal sediments alters the blue carbon sink and storage capacities in seagrass meadows by changing the rates of carbon sequestration and decomposition.
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Affiliation(s)
- Le-Zheng Qin
- Department of Biological Sciences, Pusan National University, Busan 46241, Republic of Korea
- College of Marine Science, Hainan University, Haikou 570228, China
| | - Zhaxi Suonan
- Department of Biological Sciences, Pusan National University, Busan 46241, Republic of Korea
| | - Seung Hyeon Kim
- Department of Biological Sciences, Pusan National University, Busan 46241, Republic of Korea
| | - Kun-Seop Lee
- Department of Biological Sciences, Pusan National University, Busan 46241, Republic of Korea
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16
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Tarquinio F, Attlan O, Vanderklift MA, Berry O, Bissett A. Distinct Endophytic Bacterial Communities Inhabiting Seagrass Seeds. Front Microbiol 2021; 12:703014. [PMID: 34621247 PMCID: PMC8491609 DOI: 10.3389/fmicb.2021.703014] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 07/12/2021] [Indexed: 11/13/2022] Open
Abstract
Seagrasses are marine angiosperms that can live completely or partially submerged in water and perform a variety of significant ecosystem services. Like terrestrial angiosperms, seagrasses can reproduce sexually and, the pollinated female flower develop into fruits and seeds, which represent a critical stage in the life of plants. Seed microbiomes include endophytic microorganisms that in terrestrial plants can affect seed germination and seedling health through phytohormone production, enhanced nutrient availability and defence against pathogens. However, the characteristics and origins of the seagrass seed microbiomes is unknown. Here, we examined the endophytic bacterial community of six microenvironments (flowers, fruits, and seeds, together with leaves, roots, and rhizospheric sediment) of the seagrass Halophila ovalis collected from the Swan Estuary, in southwestern Australia. An amplicon sequencing approach (16S rRNA) was used to characterize the diversity and composition of H. ovalis bacterial microbiomes and identify core microbiome bacteria that were conserved across microenvironments. Distinct communities of bacteria were observed within specific seagrass microenvironments, including the reproductive tissues (flowers, fruits, and seeds). In particular, bacteria previously associated with plant growth promoting characteristics were mainly found within reproductive tissues. Seagrass seed-borne bacteria that exhibit growth promoting traits, the ability to fix nitrogen and anti-pathogenic potential activity, may play a pivotal role in seed survival, as is common for terrestrial plants. We present the endophytic community of the seagrass seeds as foundation for the identification of potential beneficial bacteria and their selection in order to improve seagrass restoration.
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Affiliation(s)
- Flavia Tarquinio
- Oceans and Atmosphere, Indian Ocean Marine Research Centre, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Crawley, WA, Australia.,Environomics Future Science Platform, Indian Ocean Marine Research Centre, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Crawley, WA, Australia
| | - Océane Attlan
- Oceans and Atmosphere, Indian Ocean Marine Research Centre, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Crawley, WA, Australia.,Sciences et Technologies, Université de la Réunion, Saint-Denis, France
| | - Mathew A Vanderklift
- Oceans and Atmosphere, Indian Ocean Marine Research Centre, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Crawley, WA, Australia
| | - Oliver Berry
- Environomics Future Science Platform, Indian Ocean Marine Research Centre, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Crawley, WA, Australia
| | - Andrew Bissett
- Oceans and Atmosphere, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Hobart, TAS, Australia
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17
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Ling J, Zhou W, Yang Q, Yin J, Zhang J, Peng Q, Huang X, Zhang Y, Dong J. Spatial and Species Variations of Bacterial Community Structure and Putative Function in Seagrass Rhizosphere Sediment. Life (Basel) 2021; 11:life11080852. [PMID: 34440596 PMCID: PMC8401270 DOI: 10.3390/life11080852] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 08/05/2021] [Accepted: 08/11/2021] [Indexed: 12/21/2022] Open
Abstract
Seagrasses are an important part of the coral reef ecosystem, and their rhizosphere microbes are of great ecological importance. However, variations in diversity, composition, and potential functions of bacterial communities in the seagrass rhizosphere of coral reef ecosystems remain unclear. This study employed the high-throughput sequencing based on 16S rDNA gene sequences and functional annotation of prokaryotic taxa (FAPROTAX) analysis to investigate these variations based on seagrass species and sampling locations, respectively. Results demonstrated that the seagrass rhizosphere microbial community was mainly dominated by phylum Proteobacteria (33.47%), Bacteroidetes (23.33%), and Planctomycetes (12.47%), while functional groups were mainly composed of sulfate respiration (14.09%), respiration of sulfur compounds (14.24%), aerobic chemoheterotrophy (20.87%), and chemoheterotrophy (26.85%). Significant differences were evident in alpha diversity, taxonomical composition and putative functional groups based on seagrass species and sampling locations. Moreover, the core microbial community of all investigated samples was identified, accounting for 63.22% of all obtained sequences. Network analysis indicated that most microbes had a positive correlation (82.41%), and two module hubs (phylum Proteobacteria) were investigated. Furthermore, a significant positive correlation was found between the OTUs numbers obtained and the functional groups assigned for seagrass rhizosphere microbial communities (p < 0.01). Our result would facilitate future investigation of the function of seagrass rhizosphere microbes.
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Affiliation(s)
- Juan Ling
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; (J.L.); (W.Z.); (Q.Y.); (J.Y.); (J.Z.); (Q.P.); (X.H.); (Y.Z.)
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
- Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Oceanology, SCSIO, Sanya National Marine Ecosystem Research Station, Chinese Academy of Sciences, Sanya 572000, China
- Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Sciences, Guangzhou 511458, China
| | - Weiguo Zhou
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; (J.L.); (W.Z.); (Q.Y.); (J.Y.); (J.Z.); (Q.P.); (X.H.); (Y.Z.)
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
- Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Oceanology, SCSIO, Sanya National Marine Ecosystem Research Station, Chinese Academy of Sciences, Sanya 572000, China
- Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Sciences, Guangzhou 511458, China
| | - Qingsong Yang
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; (J.L.); (W.Z.); (Q.Y.); (J.Y.); (J.Z.); (Q.P.); (X.H.); (Y.Z.)
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
- Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Oceanology, SCSIO, Sanya National Marine Ecosystem Research Station, Chinese Academy of Sciences, Sanya 572000, China
- Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Sciences, Guangzhou 511458, China
| | - Jianping Yin
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; (J.L.); (W.Z.); (Q.Y.); (J.Y.); (J.Z.); (Q.P.); (X.H.); (Y.Z.)
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Jian Zhang
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; (J.L.); (W.Z.); (Q.Y.); (J.Y.); (J.Z.); (Q.P.); (X.H.); (Y.Z.)
- College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qiuying Peng
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; (J.L.); (W.Z.); (Q.Y.); (J.Y.); (J.Z.); (Q.P.); (X.H.); (Y.Z.)
- College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaofang Huang
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; (J.L.); (W.Z.); (Q.Y.); (J.Y.); (J.Z.); (Q.P.); (X.H.); (Y.Z.)
- College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuhang Zhang
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; (J.L.); (W.Z.); (Q.Y.); (J.Y.); (J.Z.); (Q.P.); (X.H.); (Y.Z.)
- College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Junde Dong
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; (J.L.); (W.Z.); (Q.Y.); (J.Y.); (J.Z.); (Q.P.); (X.H.); (Y.Z.)
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
- Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Oceanology, SCSIO, Sanya National Marine Ecosystem Research Station, Chinese Academy of Sciences, Sanya 572000, China
- Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Sciences, Guangzhou 511458, China
- Correspondence: ; Tel.: +86-20-8910-7830
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Shi Y, Yang H, Chu M, Niu X, Huo X, Gao Y, Zeng J, Lin Q, Lou K. Diversity and Spatiotemporal Dynamics of Fungal Communities in the Rhizosphere Soil of Cotton in the Arid Region of Northwest China. MICROBIAL ECOLOGY 2021; 82:87-99. [PMID: 33415384 DOI: 10.1007/s00248-020-01646-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 11/15/2020] [Indexed: 06/12/2023]
Abstract
This study aimed to investigate the fungal diversity and its temporal and spatial dynamics in the rhizosphere soil of healthy cotton by high-throughput sequencing. We studied species richness, composition, and distribution of cotton rhizosphere fungal community with respect to location (Alaer, Kuerle, Tumushuke, Hami, Shihezi, Wusu, and Jinghe) and plant growth period (seedling stage, bud stage, flowering stage, and boll-opening stage) using the methods of PCR-based high-throughput sequencing and real-time quantitative PCR. A total of 1,838,454 fungal nuclear ribosomal internal transcribed spacer region sequences (rRNA ITS) were obtained from all cotton plants sampled at different growth stages in the seven locations in Xinjiang. The most abundant fungal group in the cotton rhizosphere was the Ascomycota (78.72%), followed by the Zygomycota (9.56%) and Basidiomycota (2.77%). These sequences revealed an enormous number of operational taxonomic units (OTUs) in cotton (1802 unique OTUs), with 67-464 OTUs in a single cotton sample, at a 3% threshold and a sequencing depth of 30,000 sequences. We identified 33 classes and 389 genera from the resulting 1,800,714 sequences. Sordariomycetes was the most frequent class in all samples, followed by Leotiomycetes and Eurotiomycetes. There were some differences in OTUs among different growth stages, but the differences were not significant, with 382 OTUs (14.66%) being common to each of the stages. A marked difference in the diversity of fungi in the rhizosphere soil of cotton was evident among the different locations, with the highest number of OTUs being detected in Jinghe (1084 OTUs) and clusters of OTUs representative of northern and eastern Xinjiang being detected. There were significantly more tags of Mortierella in Jinghe and Wusu than in the other sampling sites. The dynamics of the rhizosphere fungal communities were influenced by sampling sites. To the best of our knowledge, the current study is the first application of PCR-based Illumina to characterize and compare the fungal biodiversity in multiple rhizosphere soil samples from cotton.
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Affiliation(s)
- YingWu Shi
- Institute of Microbiology, Xinjiang Academy of Agricultural Sciences, Urumqi, 830091, Xinjiang, China.
- Xinjiang Laboratory of Special Environmental Microbiology, Urumqi, 830091, Xinjiang, China.
- Key Laboratory of Agricultural Environment in Northwest Oasis of Ministry of Agriculture and Countryside, Urumqi, 830091, Xinjiang, China.
- Institute of Soil, Fertilizer and Agricultural Water Conservation, Xinjiang Academy of Agricultural Sciences, Urumqi, 830091, Xinjiang, China.
| | - HongMei Yang
- Institute of Microbiology, Xinjiang Academy of Agricultural Sciences, Urumqi, 830091, Xinjiang, China
- Xinjiang Laboratory of Special Environmental Microbiology, Urumqi, 830091, Xinjiang, China
- Key Laboratory of Agricultural Environment in Northwest Oasis of Ministry of Agriculture and Countryside, Urumqi, 830091, Xinjiang, China
| | - Ming Chu
- Institute of Microbiology, Xinjiang Academy of Agricultural Sciences, Urumqi, 830091, Xinjiang, China
- Xinjiang Laboratory of Special Environmental Microbiology, Urumqi, 830091, Xinjiang, China
- Key Laboratory of Agricultural Environment in Northwest Oasis of Ministry of Agriculture and Countryside, Urumqi, 830091, Xinjiang, China
| | - XinXiang Niu
- Key Laboratory of Agricultural Environment in Northwest Oasis of Ministry of Agriculture and Countryside, Urumqi, 830091, Xinjiang, China
- Institute of Soil, Fertilizer and Agricultural Water Conservation, Xinjiang Academy of Agricultural Sciences, Urumqi, 830091, Xinjiang, China
| | - XiangDong Huo
- Institute of Microbiology, Xinjiang Academy of Agricultural Sciences, Urumqi, 830091, Xinjiang, China
- Xinjiang Laboratory of Special Environmental Microbiology, Urumqi, 830091, Xinjiang, China
| | - Yan Gao
- Institute of Microbiology, Xinjiang Academy of Agricultural Sciences, Urumqi, 830091, Xinjiang, China
- Xinjiang Laboratory of Special Environmental Microbiology, Urumqi, 830091, Xinjiang, China
| | - Jun Zeng
- Institute of Microbiology, Xinjiang Academy of Agricultural Sciences, Urumqi, 830091, Xinjiang, China
- Xinjiang Laboratory of Special Environmental Microbiology, Urumqi, 830091, Xinjiang, China
| | - Qing Lin
- Institute of Microbiology, Xinjiang Academy of Agricultural Sciences, Urumqi, 830091, Xinjiang, China
- Xinjiang Laboratory of Special Environmental Microbiology, Urumqi, 830091, Xinjiang, China
| | - Kai Lou
- Institute of Microbiology, Xinjiang Academy of Agricultural Sciences, Urumqi, 830091, Xinjiang, China
- Xinjiang Laboratory of Special Environmental Microbiology, Urumqi, 830091, Xinjiang, China
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19
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Li M, Fang A, Yu X, Zhang K, He Z, Wang C, Peng Y, Xiao F, Yang T, Zhang W, Zheng X, Zhong Q, Liu X, Yan Q. Microbially-driven sulfur cycling microbial communities in different mangrove sediments. CHEMOSPHERE 2021; 273:128597. [PMID: 33077194 DOI: 10.1016/j.chemosphere.2020.128597] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 10/05/2020] [Accepted: 10/07/2020] [Indexed: 05/13/2023]
Abstract
Microbially-driven sulfur cycling is a vital biogeochemical process in the sulfur-rich mangrove ecosystem. It is critical to evaluate the potential impact of sulfur transformation in mangrove ecosystems. To reveal the diversity, composition, and structure of sulfur-oxidizing bacteria (SOB) and sulfate-reducing bacteria (SRB) and underlying mechanisms, we analyzed the physicochemical properties and sediment microbial communities from an introduced mangrove species (Sonneratia apetala), a native mangrove species (Kandelia obovata) and the mudflat in Hanjiang River Estuary in Guangdong (23.27°N, 116.52°E), China. The results indicated that SOB was dominated by autotrophic Thiohalophilus and chemoautotrophy Chromatium in S. apetala and K. obovata, respectively, while Desulfatibacillum was the dominant genus of SRB in K. obovata sediments. Also, the redundancy analysis indicated that temperature, redox potential (ORP), and SO42- were the significant factors influencing the sulfur cycling microbial communities with elemental sulfur (ES) as the key factor driver for SOB and total carbon (TC) for SRB in mangrove sediments. Additionally, the morphological transformation of ES, acid volatile sulfide (AVS) and SO42- explained the variation of sulfur cycling microbial communities under sulfur-rich conditions, and we found mangrove species-specific dominant Thiohalobacter, Chromatium and Desulfatibacillum, which could well use ES and SO42-, thus promoting the sulfur cycling in mangrove sediments. Meanwhile, the change of nutrient substances (TN, TC) explained why SOB were more susceptible to environmental changes than SRB. Sulfate reducing bacteria produces sulfide in anoxic sediments at depth that then migrate upward, toward fewer reducing conditions, where it's oxidized by sulfur oxidizing bacteria. This study indicates the high ability of SOB and SRB in ES, SO42-,S2- and S2- generation and transformation in sulfur-rich mangrove ecosystems, and provides novel insights into sulfur cycling in other wetland ecosystems from a microbial perspective.
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Affiliation(s)
- Mingyue Li
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China
| | - Anqi Fang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China
| | - Xiaoli Yu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China
| | - Keke Zhang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China
| | - Zhili He
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China; College of Agronomy, Hunan Agricultural University, Changsha, 410128, China
| | - Cheng Wang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China
| | - Yisheng Peng
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China
| | - Fanshu Xiao
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China.
| | - Tony Yang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China
| | - Wei Zhang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China
| | - Xiafei Zheng
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China
| | - Qiuping Zhong
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China
| | - Xingyu Liu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China
| | - Qingyun Yan
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou, 510006, China.
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20
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Wang L, Tomas F, Mueller RS. Nutrient enrichment increases size of Zostera marina shoots and enriches for sulfur and nitrogen cycling bacteria in root-associated microbiomes. FEMS Microbiol Ecol 2021; 96:5861935. [PMID: 32578844 DOI: 10.1093/femsec/fiaa129] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 06/22/2020] [Indexed: 01/09/2023] Open
Abstract
Seagrasses are vital coastal ecosystem engineers, which are mutualistically associated with microbial communities that contribute to the ecosystem services provided by meadows. The seagrass microbiome and sediment microbiota play vital roles in belowground biogeochemical and carbon cycling. These activities are influenced by nutrient, carbon and oxygen availability, all of which are modulated by environmental factors and plant physiology. Seagrass meadows are increasingly threatened by nutrient pollution, and it is unknown how the seagrass microbiome will respond to this stressor. We investigated the effects of fertilization on the physiology, morphology and microbiome of eelgrass (Zostera marina) cultivated over 4 weeks in mesocosms. We analyzed the community structure associated with eelgrass leaf, root and rhizosphere microbiomes, and of communities from water column and bulk sediment using 16S rRNA amplicon sequencing. Fertilization led to a higher number of leaves compared with that of eelgrass kept under ambient conditions. Additionally, fertilization led to enrichment of sulfur and nitrogen bacteria in belowground communities. These results suggest nutrient enrichment can stimulate belowground biogeochemical cycling, potentially exacerbating sulfide toxicity in sediments and decreasing future carbon sequestration stocks.
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Affiliation(s)
- Lu Wang
- Department of Microbiology, Oregon State University, Corvallis, OR 97331, USA
| | - Fiona Tomas
- Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR 97331, USA.,Instituto Mediterráneo de Estudios Avanzados (CSIC-UIB), C/ Miquel Marquès, 21 07190 Esporles Illes Balears, Spain
| | - Ryan S Mueller
- Department of Microbiology, Oregon State University, Corvallis, OR 97331, USA
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21
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The Seagrass Holobiont: What We Know and What We Still Need to Disclose for Its Possible Use as an Ecological Indicator. WATER 2021. [DOI: 10.3390/w13040406] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Microbes and seagrass establish symbiotic relationships constituting a functional unit called the holobiont that reacts as a whole to environmental changes. Recent studies have shown that the seagrass microbial associated community varies according to host species, environmental conditions and the host’s health status, suggesting that the microbial communities respond rapidly to environmental disturbances and changes. These changes, dynamics of which are still far from being clear, could represent a sensitive monitoring tool and ecological indicator to detect early stages of seagrass stress. In this review, the state of art on seagrass holobiont is discussed in this perspective, with the aim of disentangling the influence of different factors in shaping it. As an example, we expand on the widely studied Halophila stipulacea’s associated microbial community, highlighting the changing and the constant components of the associated microbes, in different environmental conditions. These studies represent a pivotal contribution to understanding the holobiont’s dynamics and variability pattern, and to the potential development of ecological/ecotoxicological indices. The influences of the host’s physiological and environmental status in changing the seagrass holobiont, alongside the bioinformatic tools for data analysis, are key topics that need to be deepened, in order to use the seagrass-microbial interactions as a source of ecological information.
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22
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Recovery and Community Succession of the Zostera marina Rhizobiome after Transplantation. Appl Environ Microbiol 2021; 87:AEM.02326-20. [PMID: 33187993 DOI: 10.1128/aem.02326-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 11/04/2020] [Indexed: 12/26/2022] Open
Abstract
Seagrasses can form mutualisms with their microbiomes that facilitate the exchange of energy sources, nutrients, and hormones and ultimately impact plant stress resistance. Little is known about community succession within the belowground seagrass microbiome after disturbance and its potential role in the plant's recovery after transplantation. We transplanted Zostera marina shoots with and without an intact rhizosphere and cultivated plants for 4 weeks while characterizing microbiome recovery and effects on plant traits. Rhizosphere and root microbiomes were compositionally distinct, likely representing discrete microbial niches. Furthermore, microbiomes of washed transplants were initially different from those of sod transplants and recovered to resemble an undisturbed state within 14 days. Conspicuously, changes in the microbial communities of washed transplants corresponded with changes in the rhizosphere sediment mass and root biomass, highlighting the strength and responsive nature of the relationship between plants, their microbiome, and the environment. Potential mutualistic microbes that were enriched over time include those that function in the cycling and turnover of sulfur, nitrogen, and plant-derived carbon in the rhizosphere environment. These findings highlight the importance and resilience of the seagrass microbiome after disturbance. Consideration of the microbiome will have meaningful implications for habitat restoration practices.IMPORTANCE Seagrasses are important coastal species that are declining globally, and transplantation can be used to combat these declines. However, the bacterial communities associated with seagrass rhizospheres and roots (the microbiome) are often disturbed or removed completely prior to transplantation. The seagrass microbiome benefits seagrasses through metabolite, nutrient, and phytohormone exchange and contributes to the ecosystem services of seagrass meadows by cycling sulfur, nitrogen, and carbon. This experiment aimed to characterize the importance and resilience of the seagrass belowground microbiome by transplanting Zostera marina with and without intact rhizospheres and tracking microbiome and plant morphological recovery over 4 weeks. We found the seagrass microbiome to be resilient to transplantation disturbance, recovering after 14 days. Additionally, microbiome recovery was linked with seagrass morphology, coinciding with increases in the rhizosphere sediment mass and root biomass. The results of this study can be used to include microbiome responses in informing future restoration work.
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23
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Garcias-Bonet N, Eguíluz VM, Díaz-Rúa R, Duarte CM. Host-association as major driver of microbiome structure and composition in Red Sea seagrass ecosystems. Environ Microbiol 2020; 23:2021-2034. [PMID: 33225561 DOI: 10.1111/1462-2920.15334] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 11/17/2020] [Accepted: 11/18/2020] [Indexed: 12/16/2022]
Abstract
The role of the microbiome in sustaining seagrasses has recently been highlighted. However, our understanding of the seagrass microbiome lacks behind that of other organisms. Here, we analyse the endophytic and total bacterial communities of leaves, rhizomes, and roots of six Red Sea seagrass species and their sediments. The structure of seagrass bacterial communities revealed that the 1% most abundant OTUs accounted for 87.9% and 74.8% of the total numbers of reads in sediment and plant tissue samples, respectively. We found taxonomically distinct bacterial communities in vegetated and bare sediments. Yet, our results suggest that lifestyle (i.e. free-living or host-association) is the main driver of bacterial community composition. Seagrass bacterial communities were tissue- and species-specific and differed from those of surrounding sediments. We identified OTUs belonging to genera related to N and S cycles in roots, and members of Actinobacteria, Bacteroidetes, and Firmicutes phyla as particularly enriched in root endosphere. The finding of highly similar OTUs in well-defined sub-clusters by network analysis suggests the co-occurrence of highly connected key members within Red Sea seagrass bacterial communities. These results provide key information towards the understanding of the role of microorganisms in seagrass ecosystem functioning framed under the seagrass holobiont concept.
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Affiliation(s)
- Neus Garcias-Bonet
- Red Sea Research Centre (RSRC) and Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology, Thuwal, 23955, Saudi Arabia
| | - Víctor M Eguíluz
- Red Sea Research Centre (RSRC) and Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology, Thuwal, 23955, Saudi Arabia.,Instituto de Física Interdisciplinar y Sistemas Complejos (CSIC-UIB), Palma de Mallorca, E-07122, Spain
| | - Rubén Díaz-Rúa
- Red Sea Research Centre (RSRC) and Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology, Thuwal, 23955, Saudi Arabia
| | - Carlos M Duarte
- Red Sea Research Centre (RSRC) and Computational Bioscience Research Center (CBRC), King Abdullah University of Science and Technology, Thuwal, 23955, Saudi Arabia
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24
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Sun Y, Song Z, Zhang H, Liu P, Hu X. Seagrass vegetation affect the vertical organization of microbial communities in sediment. MARINE ENVIRONMENTAL RESEARCH 2020; 162:105174. [PMID: 33099080 DOI: 10.1016/j.marenvres.2020.105174] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 09/11/2020] [Accepted: 10/06/2020] [Indexed: 06/11/2023]
Abstract
Seagrasses represent high primary productivity and provide important ecosystem services to the marine environment. Seagrass-associated microbial communities are playing essential ecological functional roles in biogeochemical cycles. However, little is known about the effect of seagrass vegetation on microbial communities in sediment. In the present study, the sediment cores of seagrass bed (dominated by Zostera japonica and Zostera marine) and degradation area in Swan Lake (China) were sampled; then, biogeochemical parameters were analyzed, and microbial community composition was investigated by using high-throughput sequencing of the 16S rRNA gene. The results showed that the presence of seagrass could lead to a decrease in the richness and diversity of the microbial community. In the vertical direction, a pronounced shift from Proteobacteria-dominated upper layers to Chloroflexi and Crenarchaeota-dominated deep layers in all sediment cores were observed. Besides, Bathyarchaeia is more abundant at degradation area, while Vibrionaceae, Sulfurovum and Lokiarchaeial overrepresent at the seagrass bed area. Vibrionaceae was abundant in the rhizosphere of Z. marina and Z. japonica, and the proportions reached 84.45% and 63.89%, respectively. This enrichment of Vibrio spp. may be caused by the macrobenthic species near the seagrass rhizosphere, and these Vibrio spp. reduced the diversity and stability of microbial community, which may lead to the degradation of seagrass. This study would provide clues for the distribution patterns and niche preferences of seagrass microbiome. The conservation strategy of seagrass would be further elucidated from the perspective of the microbiome.
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Affiliation(s)
- Yanyu Sun
- Key Laboratory of Coastal Biology and Bioresource Utilization, Yantai Institute of Costal Zone Research, Chinese Academy of Sciences, Yantai, Shandong, 264003, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong, 266237, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zenglei Song
- Key Laboratory of Coastal Biology and Bioresource Utilization, Yantai Institute of Costal Zone Research, Chinese Academy of Sciences, Yantai, Shandong, 264003, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong, 266237, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Haikun Zhang
- Key Laboratory of Coastal Biology and Bioresource Utilization, Yantai Institute of Costal Zone Research, Chinese Academy of Sciences, Yantai, Shandong, 264003, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong, 266237, China
| | - Pengyuan Liu
- Key Laboratory of Coastal Biology and Bioresource Utilization, Yantai Institute of Costal Zone Research, Chinese Academy of Sciences, Yantai, Shandong, 264003, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong, 266237, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiaoke Hu
- Key Laboratory of Coastal Biology and Bioresource Utilization, Yantai Institute of Costal Zone Research, Chinese Academy of Sciences, Yantai, Shandong, 264003, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong, 266237, China.
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25
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Elgetti Brodersen K, Kühl M, Trampe E, Koren K. Imaging O 2 dynamics and microenvironments in the seagrass leaf phyllosphere with magnetic optical sensor nanoparticles. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 104:1504-1519. [PMID: 33037691 DOI: 10.1111/tpj.15017] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 09/17/2020] [Accepted: 09/23/2020] [Indexed: 06/11/2023]
Abstract
Eutrophication leads to epiphyte blooms on seagrass leaves that strongly affect plant health, yet the actual mechanisms of such epiphyte-induced plant stress remain poorly understood. We used magnetic optical sensor nanoparticles in combination with luminescence lifetime imaging to map the O2 concentration and dynamics in the heterogeneous seagrass phyllosphere under changing light conditions. By incorporating magnetite into the sensor nanoparticles, it was possible to image the spatial O2 distribution under flow over seagrass leaf segments in the presence of a strong magnetic field. Local microniches with low leaf surface O2 concentrations were found under thick epiphytic biofilms, often leading to anoxic microhabitats in darkness. High irradiance led to O2 supersaturation across most of the seagrass phyllosphere, whereas leaf microenvironments with reduced O2 conditions were found under epiphytic biofilms at low irradiance, probably driven by self-shading. Horizontal micro-profiles extracted from the O2 images revealed pronounced heterogeneities in local O2 concentration over the base of the epiphytic biofilm, with up to 52% reduction in O2 concentrations in areas with relatively thick (>2 mm), compared with thin (≤1 mm), epiphyte layers in darkness. We also present evidence of enhanced relative internal O2 transport within leaves with epiphyte overgrowth, compared with bare seagrass leaves, in light as a result of limited mass transfer across thick outward diffusion pathways. The local availability of O2 was still markedly reduced in the epiphyte-covered leaves, however. The leaf phyllosphere is thus characterized by a complex microlandscape of O2 availability that strongly affects microbial processes occurring within the epiphytic biofilm, which may have implications for seagrass health, as anoxic microhabitats have been shown to promote the microbiological production of reduced toxic compounds, such as nitric oxide.
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Affiliation(s)
- Kasper Elgetti Brodersen
- Marine Biological Section, Department of Biology, University of Copenhagen, Strandpromenaden 5, Helsingør, 3000, Denmark
| | - Michael Kühl
- Marine Biological Section, Department of Biology, University of Copenhagen, Strandpromenaden 5, Helsingør, 3000, Denmark
| | - Erik Trampe
- Marine Biological Section, Department of Biology, University of Copenhagen, Strandpromenaden 5, Helsingør, 3000, Denmark
| | - Klaus Koren
- Marine Biological Section, Department of Biology, University of Copenhagen, Strandpromenaden 5, Helsingør, 3000, Denmark
- Department of Biology, Section for Microbiology, Aarhus University Centre for Water Technology, Ny Munkegade 114, Aarhus C, 8000, Denmark
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26
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King WL, Siboni N, Kahlke T, Dove M, O'Connor W, Mahbub KR, Jenkins C, Seymour JR, Labbate M. Regional and oyster microenvironmental scale heterogeneity in the Pacific oyster bacterial community. FEMS Microbiol Ecol 2020; 96:5813259. [PMID: 32221598 DOI: 10.1093/femsec/fiaa054] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 03/22/2020] [Indexed: 01/04/2023] Open
Abstract
Different organs of a host represent distinct microenvironments resulting in the establishment of multiple discrete bacterial communities within a host. These discrete bacterial communities can also vary according to geographical location. For the Pacific oyster, Crassostrea gigas, the factors governing bacterial diversity and abundance of different oyster microenvironments are poorly understood. In this study, the factors shaping bacterial abundance, diversity and composition associated with the C. gigas mantle, gill, adductor muscle and digestive gland were characterised using 16S (V3-V4) rRNA amplicon sequencing across six discrete estuaries. Both location and tissue-type, with tissue-type being the stronger determinant, were factors driving bacterial community composition. Bacterial communities from wave-dominated estuaries had similar compositions and higher bacterial abundance despite being geographically distant from one another, possibly indicating that functional estuarine morphology characteristics are a factor shaping the oyster bacterial community. Despite the bacterial community heterogeneity, examinations of the core bacterial community identified Spirochaetaceae bacteria as conserved across all sites and samples. Whereas members of the Vulcaniibacterium, Spirochaetaceae and Margulisbacteria, and Polynucleobacter were regionally conserved members of the digestive gland, gill and mantle bacterial communities, respectively. This indicates that baseline bacterial community profiles for specific locations are necessary when investigating bacterial communities in oyster health.
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Affiliation(s)
- William L King
- University of Technology Sydney, The School of Life Sciences, Ultimo, New South Wales, 2007, Australia.,University of Technology Sydney, Climate Change Cluster, Ultimo, New South Wales, 2007, Australia
| | - Nachshon Siboni
- University of Technology Sydney, Climate Change Cluster, Ultimo, New South Wales, 2007, Australia
| | - Tim Kahlke
- University of Technology Sydney, Climate Change Cluster, Ultimo, New South Wales, 2007, Australia
| | - Michael Dove
- NSW Department of Primary Industries, Port Stephens Fisheries Institute, Port Stephens, New South Wales, 2316, Australia
| | - Wayne O'Connor
- NSW Department of Primary Industries, Port Stephens Fisheries Institute, Port Stephens, New South Wales, 2316, Australia
| | - Khandaker Rayhan Mahbub
- University of Technology Sydney, The School of Life Sciences, Ultimo, New South Wales, 2007, Australia
| | - Cheryl Jenkins
- NSW Department of Primary Industries, Elizabeth Macarthur Agricultural Institute, Menangle, New South Wales, 2568, Australia
| | - Justin R Seymour
- University of Technology Sydney, Climate Change Cluster, Ultimo, New South Wales, 2007, Australia
| | - Maurizio Labbate
- University of Technology Sydney, The School of Life Sciences, Ultimo, New South Wales, 2007, Australia
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27
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Pedersen O, Revsbech NP, Shabala S. Microsensors in plant biology: in vivo visualization of inorganic analytes with high spatial and/or temporal resolution. JOURNAL OF EXPERIMENTAL BOTANY 2020; 71:3941-3954. [PMID: 32253437 DOI: 10.1093/jxb/eraa175] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 04/04/2020] [Indexed: 06/11/2023]
Abstract
This Expert View provides an update on the recent development of new microsensors, and briefly summarizes some novel applications of existing microsensors, in plant biology research. Two major topics are covered: (i) sensors for gaseous analytes (O2, CO2, and H2S); and (ii) those for measuring concentrations and fluxes of ions (macro- and micronutrients and environmental pollutants such as heavy metals). We show that application of such microsensors may significantly advance understanding of mechanisms of plant-environmental interaction and regulation of plant developmental and adaptive responses under adverse environmental conditions via non-destructive visualization of key analytes with high spatial and/or temporal resolution. Examples included cover a broad range of environmental situations including hypoxia, salinity, and heavy metal toxicity. We highlight the power of combining microsensor technology with other advanced biophysical (patch-clamp, voltage-clamp, and single-cell pressure probe), imaging (MRI and fluorescent dyes), and genetic techniques and approaches. We conclude that future progress in the field may be achieved by applying existing microsensors for important signalling molecules such as NO and H2O2, by improving selectivity of existing microsensors for some key analytes (e.g. Na, Mg, and Zn), and by developing new microsensors for P.
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Affiliation(s)
- Ole Pedersen
- Department of Biology, University of Copenhagen, Denmark
- School of Agriculture and Environment, The University of Western Australia, Australia
| | - Niels Peter Revsbech
- Aarhus University Centre for Water Technology, Department of Bioscience, Aarhus University, Denmark
| | - Sergey Shabala
- School of Land and Food, University of Tasmania, Australia
- International Research Centre for Environmental Membrane Biology, Foshan University, China
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28
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Scholz VV, Müller H, Koren K, Nielsen LP, Meckenstock RU. The rhizosphere of aquatic plants is a habitat for cable bacteria. FEMS Microbiol Ecol 2020; 95:5485638. [PMID: 31054245 PMCID: PMC6510695 DOI: 10.1093/femsec/fiz062] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 05/03/2019] [Indexed: 11/15/2022] Open
Abstract
Cable bacteria belonging to the family Desulfobulbaceae couple sulfide oxidation and oxygen reduction by long-distance electron transfer over centimeter distances in marine and freshwater sediments. In such habitats, aquatic plants can release oxygen into the rhizosphere. Hence, the rhizosphere constitutes an ideal habitat for cable bacteria, which have been reported on seagrass roots recently. Here, we employ experimental approaches to investigate activity, abundance, and spatial orientation of cable bacteria next to the roots of the freshwater plant Littorella uniflora. Fluorescence in situ hybridization (FISH), in combination with oxygen-sensitive planar optodes, demonstrated that cable bacteria densities are enriched at the oxic–anoxic transition zone next to roots compared to the bulk sediment in the same depth. Scanning electron microscopy showed cable bacteria along root hairs. Electric potential measurements showed a lateral electric field over centimeters from the roots, indicating cable bacteria activity. In addition, FISH revealed that cable bacteria were present in the rhizosphere of Oryza sativa (rice), Lobelia cardinalis and Salicornia europaea. Hence, the interaction of cable bacteria with aquatic plants of different growth forms and habitats indicates that the plant root–cable bacteria interaction might be a common property of aquatic plant rhizospheres.
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Affiliation(s)
- Vincent V Scholz
- Biofilm Centre, University of Duisburg-Essen, Universitätsstr. 5, 45141 Essen, Germany.,Center for Electromicrobiology, Aarhus University, Ny Munkegade 116, DK-8000 Aarhus C, Denmark
| | - Hubert Müller
- Biofilm Centre, University of Duisburg-Essen, Universitätsstr. 5, 45141 Essen, Germany
| | - Klaus Koren
- Aarhus University Centre for Water Technology, Section for Microbiology, Department of Bioscience, Aarhus University, Ny Munkegade 116, DK-8000 Aarhus C, Denmark
| | - Lars Peter Nielsen
- Center for Electromicrobiology, Aarhus University, Ny Munkegade 116, DK-8000 Aarhus C, Denmark
| | - Rainer U Meckenstock
- Biofilm Centre, University of Duisburg-Essen, Universitätsstr. 5, 45141 Essen, Germany
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Gagnon K, Rinde E, Bengil EGT, Carugati L, Christianen MJA, Danovaro R, Gambi C, Govers LL, Kipson S, Meysick L, Pajusalu L, Tüney Kızılkaya İ, Koppel J, Heide T, Katwijk MM, Boström C. Facilitating foundation species: The potential for plant–bivalve interactions to improve habitat restoration success. J Appl Ecol 2020. [DOI: 10.1111/1365-2664.13605] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Karine Gagnon
- Environmental and Marine Biology Åbo Akademi University Turku Finland
| | - Eli Rinde
- Norwegian Institute for Water Research Oslo Norway
| | - Elizabeth G. T. Bengil
- Mediterranean Conservation Society Izmir Turkey
- Girne American UniversityMarine School Girne TRNC via Turkey
| | - Laura Carugati
- Department of Life and Environmental Sciences Polytechnic University of Marche Ancona Italy
| | - Marjolijn J. A. Christianen
- Aquatic Ecology and Water Quality Management Group Wageningen University Wageningen The Netherlands
- Department of Environmental Science Institute for Wetland and Water Research Radboud University Nijmegen Nijmegen The Netherlands
| | - Roberto Danovaro
- Department of Life and Environmental Sciences Polytechnic University of Marche Ancona Italy
- Stazione Zoologica Anton Dohrn Naples Italy
| | - Cristina Gambi
- Department of Life and Environmental Sciences Polytechnic University of Marche Ancona Italy
| | - Laura L. Govers
- Department of Environmental Science Institute for Wetland and Water Research Radboud University Nijmegen Nijmegen The Netherlands
- Groningen Institute for Evolutionary Life Sciences University of Groningen Groningen The Netherlands
| | - Silvija Kipson
- Faculty of Science Department of Biology University of Zagreb Zagreb Croatia
| | - Lukas Meysick
- Environmental and Marine Biology Åbo Akademi University Turku Finland
| | - Liina Pajusalu
- Estonian Marine Institute University of Tartu Tallinn Estonia
| | - İnci Tüney Kızılkaya
- Mediterranean Conservation Society Izmir Turkey
- Faculty of Science Ege University Izmir Turkey
| | - Johan Koppel
- Groningen Institute for Evolutionary Life Sciences University of Groningen Groningen The Netherlands
- Royal Netherlands Institute for Sea Research and Utrecht University Yerseke The Netherlands
| | - Tjisse Heide
- Department of Environmental Science Institute for Wetland and Water Research Radboud University Nijmegen Nijmegen The Netherlands
- Groningen Institute for Evolutionary Life Sciences University of Groningen Groningen The Netherlands
- Department of Coastal Systems Royal Netherlands Institute of Sea Research and Utrecht University Den Burg The Netherlands
| | - Marieke M. Katwijk
- Department of Environmental Science Institute for Wetland and Water Research Radboud University Nijmegen Nijmegen The Netherlands
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Trevathan-Tackett SM, Jeffries TC, Macreadie PI, Manojlovic B, Ralph P. Long-term decomposition captures key steps in microbial breakdown of seagrass litter. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 705:135806. [PMID: 31838420 DOI: 10.1016/j.scitotenv.2019.135806] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 11/25/2019] [Accepted: 11/26/2019] [Indexed: 06/10/2023]
Abstract
Seagrass biomass represents an important source of organic carbon that can contribute to long-term sediment carbon stocks in coastal ecosystems. There is little empirical data on the long-term microbial decomposition of seagrass detritus, despite this process being one of the key drivers of carbon-cycling in coastal ecosystems, that is, it influences the amount and quality of carbon available for sequestration. Here, our goal was to investigate how litter quality (leaf vs. rhizome/root) and the microbial communities involved in organic matter remineralisation shift over a 2-year field decomposition study north of Sydney, Australia using the temperate seagrass Zostera muelleri. The sites varied in bulk sediment characteristics and the sediment-associated microbial communities, but these variables overall had little influence on long-term seagrass decomposition rates or seagrass-associated microbiomes. The results showed a clear succession of bacterial and archaeal communities for both tissues types from r-strategists such as α- and γ-proteobacteria to K-strategies, including δ-proteobacteria, Bacteroidia and Spirochaetes. We used a new mathematical model to capture how decay rates varied over time and found that two decomposition events occurred for some seagrass leaf samples, possibly due to exudate input from living seagrass roots growing into the litter bag. The new model also indicated that conventional single exponential models overestimate long-term decay rates, and we detected for the first time the refractory, or stable, phase of decomposition for rhizome/root biomass. The stable phase began at approximately 20% mass remaining and after 600 days, and the persistence of rhizome/root biomass was attributed to the anoxic conditions and the preservation of refractory organic matter. While we predict that rhizome/root biomass will contribute more to the long-term sediment carbon stocks, the preservation of leaf carbon may be enhanced at locations were sedimentation is high and burial in anoxic conditions is rapid and constant.
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Affiliation(s)
- Stacey M Trevathan-Tackett
- Climate Change Cluster, University of Technology Sydney, Ultimo, NSW 2007, Australia; Deakin University, Geelong, School of Life and Environmental Sciences, Centre for Integrative Ecology, Burwood Campus, VIC 3125, Australia.
| | - Thomas C Jeffries
- Climate Change Cluster, University of Technology Sydney, Ultimo, NSW 2007, Australia; School of Science and Health, University of Western Sydney, Penrith, NSW 2751, Australia; Hawkesbury Institute for the Environment, University of Western Sydney, Penrith, NSW 2751, Australia
| | - Peter I Macreadie
- Climate Change Cluster, University of Technology Sydney, Ultimo, NSW 2007, Australia; Deakin University, Geelong, School of Life and Environmental Sciences, Centre for Integrative Ecology, Burwood Campus, VIC 3125, Australia
| | - Bojana Manojlovic
- Climate Change Cluster, University of Technology Sydney, Ultimo, NSW 2007, Australia
| | - Peter Ralph
- Climate Change Cluster, University of Technology Sydney, Ultimo, NSW 2007, Australia
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George R, Gullström M, Mtolera MSP, Lyimo TJ, Björk M. Methane emission and sulfide levels increase in tropical seagrass sediments during temperature stress: A mesocosm experiment. Ecol Evol 2020; 10:1917-1928. [PMID: 32128125 PMCID: PMC7042687 DOI: 10.1002/ece3.6009] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 12/18/2019] [Accepted: 12/23/2019] [Indexed: 11/11/2022] Open
Abstract
Climate change-induced ocean warming is expected to greatly affect carbon dynamics and sequestration in vegetated shallow waters, especially in the upper subtidal where water temperatures may fluctuate considerably and can reach high levels at low tides. This might alter the greenhouse gas balance and significantly reduce the carbon sink potential of tropical seagrass meadows. In order to assess such consequences, we simulated temperature stress during low tide exposures by subjecting seagrass plants (Thalassia hemprichii) and associated sediments to elevated midday temperature spikes (31, 35, 37, 40, and 45°C) for seven consecutive days in an outdoor mesocosm setup. During the experiment, methane release from the sediment surface was estimated using gas chromatography. Sulfide concentration in the sediment pore water was determined spectrophotometrically, and the plant's photosynthetic capacity as electron transport rate (ETR), and maximum quantum yield (Fv/Fm) was assessed using pulse amplitude modulated (PAM) fluorometry. The highest temperature treatments (40 and 45°C) had a clear positive effect on methane emission and the level of sulfide in the sediment and, at the same time, clear negative effects on the photosynthetic performance of seagrass plants. The effects observed by temperature stress were immediate (within hours) and seen in all response variables, including ETR, Fv/Fm, methane emission, and sulfide levels. In addition, both the methane emission and the size of the sulfide pool were already negatively correlated with changes in the photosynthetic rate (ETR) during the first day, and with time, the correlations became stronger. These findings show that increased temperature will reduce primary productivity and increase methane and sulfide levels. Future increases in the frequency and severity of extreme temperature events could hence reduce the climate mitigation capacity of tropical seagrass meadows by reducing CO2 sequestration, increase damage from sulfide toxicity, and induce the release of larger amounts of methane.
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Affiliation(s)
- Rushingisha George
- Department of Ecology, Environment and Plant SciencesSeagrass Ecology and Physiology groupStockholm UniversityStockholmSweden
- Tanzania Fisheries Research Institute (TAFIRI)Dar es SalaamTanzania
| | - Martin Gullström
- Department of Ecology, Environment and Plant SciencesSeagrass Ecology and Physiology groupStockholm UniversityStockholmSweden
- Department of Biological and Environmental SciencesUniversity of GothenburgKristineberg, FiskebäckskilSweden
| | | | - Thomas J. Lyimo
- Department of Molecular Science and BiotechnologyUniversity of Dar es SalaamDar es SalaamTanzania
| | - Mats Björk
- Department of Ecology, Environment and Plant SciencesSeagrass Ecology and Physiology groupStockholm UniversityStockholmSweden
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Brodersen KE, Koren K, Revsbech NP, Kühl M. Strong leaf surface basification and CO 2 limitation of seagrass induced by epiphytic biofilm microenvironments. PLANT, CELL & ENVIRONMENT 2020; 43:174-187. [PMID: 31429088 DOI: 10.1111/pce.13645] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 08/07/2019] [Accepted: 08/09/2019] [Indexed: 06/10/2023]
Abstract
Coastal eutrophication is a growing problem worldwide, leading to increased epiphyte overgrowth of seagrass leaves. Yet little is known about how epiphytes affect key biogeochemical conditions and processes in the seagrass phyllosphere. We used electrochemical microsensors to measure microgradients of O2 , pH, and CO2 at the bare and epiphyte-covered leaf surface of seagrass (Zostera marina L.) to determine effects of epiphytes on the leaf chemical microenvironment. Epiphytes result in extreme daily fluctuations in pH, O2 , and inorganic carbon concentrations at the seagrass leaf surface severely hampering the plant's performance. In light, leaf epiphyte biofilms and their diffusive boundary layer lead to strong basification, markedly reducing the CO2 and HCO3- availability at the leaf surface, leading to reduced photosynthetic efficiency as a result of carbon limitation and enhanced photorespiration. With epiphytes, leaf surface pH increased to >10, thereby exceeding final pH levels (~9.62) and CO2 compensation points for active photosynthesis. In darkness, epiphyte biofilms resulted in increased CO2 and hypoxia at the leaf surface. Epiphytes can lead to severe carbon limitation in seagrasses owing to strong phyllosphere basification leading to CO2 depletion and costly, yet limiting, HCO3- utilization, increasing the risk of plant starvation.
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Affiliation(s)
| | - Klaus Koren
- Department of Bioscience, Aarhus University Centre for Water Technology, Aarhus C, Denmark
| | - Niels Peter Revsbech
- Department of Bioscience, Aarhus University Centre for Water Technology, Aarhus C, Denmark
| | - Michael Kühl
- Marine Biological Section, Department of Biology, University of Copenhagen, Helsingør, Denmark
- Climate Change Cluster, Faculty of Science, University of Technology Sydney, Sydney, Australia
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Rapid Metabolome and Bioactivity Profiling of Fungi Associated with the Leaf and Rhizosphere of the Baltic Seagrass Zostera marina. Mar Drugs 2019; 17:md17070419. [PMID: 31330983 PMCID: PMC6669648 DOI: 10.3390/md17070419] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 07/15/2019] [Accepted: 07/16/2019] [Indexed: 01/30/2023] Open
Abstract
Zostera marina (eelgrass) is a marine foundation species with key ecological roles in coastal habitats. Its bacterial microbiota has been well studied, but very little is known about its mycobiome. In this study, we have isolated and identified 13 fungal strains, dominated by Penicillium species (10 strains), from the leaf and the root rhizosphere of Baltic Z. marina. The organic extracts of the fungi that were cultured by an OSMAC (One-Strain–Many-Compounds) regime using five liquid culture media under both static and shaking conditions were investigated for their chemical and bioactivity profiles. All extracts showed strong anti-quorum sensing activity, and the majority of the Penicillium extracts displayed antimicrobial or anti-biofilm activity against Gram-negative environmental marine and human pathogens. HPLC-DAD-MS-based rapid metabolome analyses of the extracts indicated the high influence of culture conditions on the secondary metabolite (SM) profiles. Among 69 compounds detected in all Penicillium sp. extracts, 46 were successfully dereplicated. Analysis of SM relatedness in culture conditions by Hierarchical Cluster Analysis (HCA) revealed generally low similarity and showed a strong effect of medium selection on chemical profiles of Penicillium sp. This is the first study assessing both the metabolite and bioactivity profile of the fungi associated with Baltic eelgrass Z. marina.
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Hurtado-McCormick V, Kahlke T, Petrou K, Jeffries T, Ralph PJ, Seymour JR. Regional and Microenvironmental Scale Characterization of the Zostera muelleri Seagrass Microbiome. Front Microbiol 2019; 10:1011. [PMID: 31139163 PMCID: PMC6527750 DOI: 10.3389/fmicb.2019.01011] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 04/23/2019] [Indexed: 11/29/2022] Open
Abstract
Seagrasses are globally distributed marine plants that represent an extremely valuable component of coastal ecosystems. Like terrestrial plants, seagrass productivity and health are likely to be strongly governed by the structure and function of the seagrass microbiome, which will be distributed across a number of discrete microenvironments within the plant, including the phyllosphere, the endosphere and the rhizosphere, all different in physical and chemical conditions. Here we examined patterns in the composition of the microbiome of the seagrass Zostera muelleri, within six plant-associated microenvironments sampled across four different coastal locations in New South Wales, Australia. Amplicon sequencing approaches were used to characterize the diversity and composition of bacterial, microalgal, and fungal microbiomes and ultimately identify "core microbiome" members that were conserved across sampling microenvironments. Discrete populations of bacteria, microalgae and fungi were observed within specific seagrass microenvironments, including the leaves and roots and rhizomes, with "core" taxa found to persist within these microenvironments across geographically disparate sampling sites. Bacterial, microalgal and fungal community profiles were most strongly governed by intrinsic features of the different seagrass microenvironments, whereby microscale differences in community composition were greater than the differences observed between sampling regions. However, our results showed differing strengths of microbial preferences at the plant scale, since this microenvironmental variability was more pronounced for bacteria than it was for microalgae and fungi, suggesting more specific interactions between the bacterial consortia and the seagrass host, and potentially implying a highly specialized coupling between seagrass and bacterial metabolism and ecology. Due to their persistence within a given seagrass microenvironment, across geographically discrete sampling locations, we propose that the identified "core" microbiome members likely play key roles in seagrass physiology as well as the ecology and biogeochemistry of seagrass habitats.
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Affiliation(s)
| | - Tim Kahlke
- Climate Change Cluster, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia
| | - Katherina Petrou
- School of Life Sciences, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia
| | - Thomas Jeffries
- School of Science and Health, Western Sydney University, Penrith, NSW, Australia
| | - Peter J. Ralph
- Climate Change Cluster, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia
| | - Justin Robert Seymour
- Climate Change Cluster, Faculty of Science, University of Technology Sydney, Ultimo, NSW, Australia
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Moßhammer M, Brodersen KE, Kühl M, Koren K. Nanoparticle- and microparticle-based luminescence imaging of chemical species and temperature in aquatic systems: a review. Mikrochim Acta 2019; 186:126. [PMID: 30680465 DOI: 10.1007/s00604-018-3202-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 12/20/2018] [Indexed: 11/25/2022]
Abstract
Most aquatic systems rely on a multitude of biogeochemical processes that are coupled with each other in a complex and dynamic manner. To understand such processes, minimally invasive analytical tools are required that allow continuous, real-time measurements of individual reactions in these complex systems. Optical chemical sensors can be used in the form of fiber-optic sensors, planar sensors, or as micro- and nanoparticles (MPs and NPs). All have their specific merits, but only the latter allow for visualization and quantification of chemical gradients over 3D structures. This review (with 147 references) summarizes recent developments mainly in the field of optical NP sensors relevant for chemical imaging in aquatic science. The review encompasses methods for signal read-out and imaging, preparation of NPs and MPs, and an overview of relevant MP/NP-based sensors. Additionally, examples of MP/NP-based sensors in aquatic systems such as corals, plant tissue, biofilms, sediments and water-sediment interfaces, marine snow and in 3D bioprinting are given. We also address current challenges and future perspectives of NP-based sensing in aquatic systems in a concluding section. Graphical abstract ᅟ.
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Affiliation(s)
- Maria Moßhammer
- Marine Biological Section, Department of Biology, University of Copenhagen, 3000, Helsingør, Denmark
| | - Kasper Elgetti Brodersen
- Marine Biological Section, Department of Biology, University of Copenhagen, 3000, Helsingør, Denmark
| | - Michael Kühl
- Marine Biological Section, Department of Biology, University of Copenhagen, 3000, Helsingør, Denmark.
- Climate Change Cluster, University of Technology Sydney, Ultimo, NSW, 2007, Australia.
| | - Klaus Koren
- Aarhus University Center for Water Technology, Department of Bioscience - Microbiology, Aarhus University, 8000, Aarhus, Denmark.
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