Pub Date : 2024-11-28DOI: 10.1016/j.marenvres.2024.106877
Rodríguez-Salazar Claudia Lorena , Comas-García Mauricio , Muñoz Tenería Fernando Alberto , Zenteno-Savín Tania , Labrada-Martagón Vanessa
Tourism, urban development, and sargasso beaching caused environmental alterations in the Mexican Caribbean coasts. Little ecotoxicological information exists on the green turtle (Chelonia mydas) population inhabiting this region. Micronucleus (MN) and erythrocytic nuclear abnormalities (ENA) tests are non-destructive DNA damage biomarkers. We aimed to determine local (Punta Arenas, Akumal, Punta Herrero, and Xcalak) and annual (2015–2019) variability in MN/ENA frequency to understand genotoxic damage extent. Almost all the individuals sampled (n = 166) presented DNA damage (98.8%); the lack of correlations between MN/ENA and biological variables confirmed the usefulness of these tests as biomarkers. The southern foraging site had the highest number of MN/ENA; an increase over time was found in the most urbanized and the most protected sites, coinciding with previously reported regional variability of persistent organic compounds, heavy metals, and annual massive influx of sargasso. Considering the sentinel status of green turtles, the advantages of the blood tests, and the continuous accelerated urban development in the Caribbean, long-term monitoring of this species is advised.
{"title":"Genotoxic damage in green turtles (Chelonia mydas) exhibits regional and annual fluctuations","authors":"Rodríguez-Salazar Claudia Lorena , Comas-García Mauricio , Muñoz Tenería Fernando Alberto , Zenteno-Savín Tania , Labrada-Martagón Vanessa","doi":"10.1016/j.marenvres.2024.106877","DOIUrl":"10.1016/j.marenvres.2024.106877","url":null,"abstract":"<div><div>Tourism, urban development, and sargasso beaching caused environmental alterations in the Mexican Caribbean coasts. Little ecotoxicological information exists on the green turtle (<em>Chelonia mydas</em>) population inhabiting this region. Micronucleus (MN) and erythrocytic nuclear abnormalities (ENA) tests are non-destructive DNA damage biomarkers. We aimed to determine local (Punta Arenas, Akumal, Punta Herrero, and Xcalak) and annual (2015–2019) variability in MN/ENA frequency to understand genotoxic damage extent. Almost all the individuals sampled (<em>n</em> = 166) presented DNA damage (98.8%); the lack of correlations between MN/ENA and biological variables confirmed the usefulness of these tests as biomarkers. The southern foraging site had the highest number of MN/ENA; an increase over time was found in the most urbanized and the most protected sites, coinciding with previously reported regional variability of persistent organic compounds, heavy metals, and annual massive influx of sargasso. Considering the sentinel status of green turtles, the advantages of the blood tests, and the continuous accelerated urban development in the Caribbean, long-term monitoring of this species is advised.</div></div>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"Article 106877"},"PeriodicalIF":3.0,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-28DOI: 10.1016/j.marenvres.2024.106859
Feichao Du , Yuhang Li , Gust Bilcke , Shinya Sato , Kuidong Xu
Extreme climate events, such as marine heatwaves (MHWs), are expected to occur more frequently and intensely in the future, resulting in a substantial impact on marine life. The way that diatoms respond to MHWs may have crucial effects on global primary production and biogeochemical cycles. Euplanktonic diatoms appear to benefit from MHWs directly, but this phenomenon needs an explanation. As concerns tychoplanktonic and benthic diatoms, no studies have been addressed on their thermal response strategies. To address this, we investigated the responses and underlying mechanisms of three typical growth forms of diatoms, Pseudo-nitzschia multiseries (euplanktonic), Paralia guyana (tychoplanktonic) and Navicula avium (benthic), under heat stress by combining a growth experiment with transcriptomic analysis. Our results showed that the physiological responses of diatoms to MHWs and underlying molecular mechanisms are largely related to their growth forms. The euplanktonic diatom was first depressed, but then had a distinct increase in the growth rate accompanied by inducing zeatin and unsaturated fatty acid biosynthesis and repressing substance assimilation and energy metabolism. Contrarily, the benthic diatom showed elevated substance and energy demands for macromolecules accumulation by reducing cell division and increasing photosynthesis and nitrogen assimilation. The tychoplanktonic diatom exhibited higher physiological plasticity to maintain growth and cellular homeostasis. Our results indicate the increased rate of cell division in euplanktonic diatoms under heat stress is likely an emergency response strategy promoting diatom dispersal for survival, but at the cost of disturbances of metabolic balance.
{"title":"Distinct interspecies thermal resistance strategies exhibited by euplanktonic, tychoplanktonic and benthic diatoms under marine heatwaves","authors":"Feichao Du , Yuhang Li , Gust Bilcke , Shinya Sato , Kuidong Xu","doi":"10.1016/j.marenvres.2024.106859","DOIUrl":"10.1016/j.marenvres.2024.106859","url":null,"abstract":"<div><div>Extreme climate events, such as marine heatwaves (MHWs), are expected to occur more frequently and intensely in the future, resulting in a substantial impact on marine life. The way that diatoms respond to MHWs may have crucial effects on global primary production and biogeochemical cycles. Euplanktonic diatoms appear to benefit from MHWs directly, but this phenomenon needs an explanation. As concerns tychoplanktonic and benthic diatoms, no studies have been addressed on their thermal response strategies. To address this, we investigated the responses and underlying mechanisms of three typical growth forms of diatoms, <em>Pseudo-nitzschia multiseries</em> (euplanktonic), <em>Paralia guyana</em> (tychoplanktonic) and <em>Navicula avium</em> (benthic), under heat stress by combining a growth experiment with transcriptomic analysis. Our results showed that the physiological responses of diatoms to MHWs and underlying molecular mechanisms are largely related to their growth forms. The euplanktonic diatom was first depressed, but then had a distinct increase in the growth rate accompanied by inducing zeatin and unsaturated fatty acid biosynthesis and repressing substance assimilation and energy metabolism. Contrarily, the benthic diatom showed elevated substance and energy demands for macromolecules accumulation by reducing cell division and increasing photosynthesis and nitrogen assimilation. The tychoplanktonic diatom exhibited higher physiological plasticity to maintain growth and cellular homeostasis. Our results indicate the increased rate of cell division in euplanktonic diatoms under heat stress is likely an emergency response strategy promoting diatom dispersal for survival, but at the cost of disturbances of metabolic balance.</div></div>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"Article 106859"},"PeriodicalIF":3.0,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142759422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-28DOI: 10.1016/j.marenvres.2024.106878
Adriana P Nascimento, Rufino Neto A Azevedo, Marília Gabriela A Pereira, Danielle M M Franco, Boniek G Vaz, André H B Oliveira, Jandyson M Santos, Rivelino M Cavalcante, Laercio L Martins
This work applied the forensic environmental geochemistry assessment to evaluate the tarballs that contaminated the coast of Brazil in late 2022. Accordingly, saturated and aromatic biomarkers were analyzed by gas chromatography and acidic polar compounds by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) of 16 tarball samples from beaches of five Brazilian states. All samples presented waxy characteristics and are from the same source, highlighting the large coast extension affected by this event (∼3,000 km). However, they have distinct sources from the spilled oils stranded on the Brazilian coast in 2019 and early 2022, as they present distinct fingerprints related to the distribution of resistant biomarkers, including the triaromatic steroids, tricyclic and pentacyclic terpanes, and steranes, which mirrors in significantly different diagnostic ratios. Biomarkers indicate their characteristics of mature and marine crude oils (not fuel). Furthermore, all samples presented low weathering levels, indicating their fate as a high-persistence contaminant in the environment. These tarballs likely originated from the washing processes of ship tanks and persisted drifting on the sea until they arrived on the Brazilian coast.
{"title":"Forensic environmental geochemistry to reveal the extent, characteristics, and fate of waxy tarballs spilled over the northeast coast of Brazil in 2022.","authors":"Adriana P Nascimento, Rufino Neto A Azevedo, Marília Gabriela A Pereira, Danielle M M Franco, Boniek G Vaz, André H B Oliveira, Jandyson M Santos, Rivelino M Cavalcante, Laercio L Martins","doi":"10.1016/j.marenvres.2024.106878","DOIUrl":"https://doi.org/10.1016/j.marenvres.2024.106878","url":null,"abstract":"<p><p>This work applied the forensic environmental geochemistry assessment to evaluate the tarballs that contaminated the coast of Brazil in late 2022. Accordingly, saturated and aromatic biomarkers were analyzed by gas chromatography and acidic polar compounds by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) of 16 tarball samples from beaches of five Brazilian states. All samples presented waxy characteristics and are from the same source, highlighting the large coast extension affected by this event (∼3,000 km). However, they have distinct sources from the spilled oils stranded on the Brazilian coast in 2019 and early 2022, as they present distinct fingerprints related to the distribution of resistant biomarkers, including the triaromatic steroids, tricyclic and pentacyclic terpanes, and steranes, which mirrors in significantly different diagnostic ratios. Biomarkers indicate their characteristics of mature and marine crude oils (not fuel). Furthermore, all samples presented low weathering levels, indicating their fate as a high-persistence contaminant in the environment. These tarballs likely originated from the washing processes of ship tanks and persisted drifting on the sea until they arrived on the Brazilian coast.</p>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"106878"},"PeriodicalIF":3.0,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142780551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-27DOI: 10.1016/j.marenvres.2024.106875
Melisa Aranza Sánchez-Rojas , Ana Carolina Ruiz-Fernández , Brigitta I. van Tussenbroek , Joan-Albert Sanchez-Cabeza , Libia Hascibe Pérez-Bernal , José Gilberto Cardoso-Mohedano
Seagrass meadow sediments are efficient organic carbon (Corg) sinks and can store Corg for hundreds of years. The temporal variation of Corg burial rates and stocks over recent decades at nearshore seagrass meadows in the Puerto Morelos Reef Lagoon, Mexico, was evaluated in 210Pb-dated sediment cores from nearshore meadows dominated by Thalassia testudinum. The sediments were predominantly sandy (>52% sand) rich in carbonate grains (11.8–12.5% Cinorg) with minor Corg (0.24–1.12%) and Norg (0.02–0.13%) concentrations. The C:N ratio (9.4–13.0) indicated that marine-derived Corg was prevalent. Corg stocks in the upper 30 cm sediment were 15.9 ± 3.0–24.8 ± 4.6 Mg ha−1. Sedimentary mass accumulation rates (MAR) (0.7–1.5 g cm−2 yr−1) were higher than those previously recorded in seagrass sediments from the reef lagoon and other parts of the world. The highest MAR values, recorded in 2015 (±0.13) and 2018 (±0.03), coincided with the peak sargassum influx years. MAR and Corg burial rates (11.4–133 g m−2 yr−1) were correlated (r2 = 0.76), indicating that the massive influxes of sargassum have accelerated Corg burial rates in the region since 2015. This study marks the initial evaluation of the interaction between the massive influx of sargassum, MAR, and Corg burial rates in seagrass sediments, potentially laying the groundwork for future extended monitoring initiatives.
{"title":"Quantifying organic carbon burial rates and stocks in seagrass meadow sediments influenced by sargassum-brown tides","authors":"Melisa Aranza Sánchez-Rojas , Ana Carolina Ruiz-Fernández , Brigitta I. van Tussenbroek , Joan-Albert Sanchez-Cabeza , Libia Hascibe Pérez-Bernal , José Gilberto Cardoso-Mohedano","doi":"10.1016/j.marenvres.2024.106875","DOIUrl":"10.1016/j.marenvres.2024.106875","url":null,"abstract":"<div><div>Seagrass meadow sediments are efficient organic carbon (C<sub>org</sub>) sinks and can store C<sub>org</sub> for hundreds of years. The temporal variation of C<sub>org</sub> burial rates and stocks over recent decades at nearshore seagrass meadows in the Puerto Morelos Reef Lagoon, Mexico, was evaluated in <sup>210</sup>Pb-dated sediment cores from nearshore meadows dominated by <em>Thalassia testudinum.</em> The sediments were predominantly sandy (>52% sand) rich in carbonate grains (11.8–12.5% C<sub>inorg</sub>) with minor C<sub>org</sub> (0.24–1.12%) and N<sub>org</sub> (0.02–0.13%) concentrations. The C:N ratio (9.4–13.0) indicated that marine-derived C<sub>org</sub> was prevalent. C<sub>org</sub> stocks in the upper 30 cm sediment were 15.9 ± 3.0–24.8 ± 4.6 Mg ha<sup>−1</sup>. Sedimentary mass accumulation rates (MAR) (0.7–1.5 g cm<sup>−2</sup> yr<sup>−1</sup>) were higher than those previously recorded in seagrass sediments from the reef lagoon and other parts of the world. The highest MAR values, recorded in 2015 (±0.13) and 2018 (±0.03), coincided with the peak sargassum influx years. MAR and C<sub>org</sub> burial rates (11.4–133 g m<sup>−2</sup> yr<sup>−1</sup>) were correlated (r<sup>2</sup> = 0.76), indicating that the massive influxes of sargassum have accelerated C<sub>org</sub> burial rates in the region since 2015. This study marks the initial evaluation of the interaction between the massive influx of sargassum, MAR, and C<sub>org</sub> burial rates in seagrass sediments, potentially laying the groundwork for future extended monitoring initiatives.</div></div>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"Article 106875"},"PeriodicalIF":3.0,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142759355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-27DOI: 10.1016/j.marenvres.2024.106861
Li-Gong Zou, Fu-Fang Wen, Xiao Zhang, Gang Li, Qing Wang, Hong-Ye Li, Yu-Feng Yang
In the intricate realm of aquatic ecosystems, biotic interactions play pivotal roles in shaping the physiological responses and survival strategies of microorganisms. This study investigates the effects of Gracilaria bailinae on photosynthesis and metabolism on the diatom Phaeodactylum tricornutum and the ecological significance. Our results reveal considerable suppression by G. bailinae on both its light-dependent and light-independent reactions of photosynthesis in P. tricornutum. A pronounced decline in carbon fixation was observed causing. the diatom to prioritize its carbon flux towards carbohydrate synthesis for its cellular energy needs. At high G. bailinae concentrations a marked reduction in lipid content indicated their importance as emergency energy sources. This response in lipid mobilization under photosynthetic stress is an evolutionary strategy for environmental adaptation. In addition, G. bailinae-induced stress amplified lysosomal activity in the diatom. Such an upsurge in oxidative stress appears to fast-track cellular death. We conclude that the ROS production, induced by G. bailinae, acts as a linchpin in mediating stress responses, thereby significantly reconfiguring the metabolism in the diatom. This study not only elucidates the physiological countermeasures of microalgae against biotic stressors but it also underscores the complex interactions between aquatic microorganisms.
{"title":"Mechanistic impact of Gracilaria bailinae extracts on photosynthesis and metabolism in Phaeodactylum tricornutum.","authors":"Li-Gong Zou, Fu-Fang Wen, Xiao Zhang, Gang Li, Qing Wang, Hong-Ye Li, Yu-Feng Yang","doi":"10.1016/j.marenvres.2024.106861","DOIUrl":"https://doi.org/10.1016/j.marenvres.2024.106861","url":null,"abstract":"<p><p>In the intricate realm of aquatic ecosystems, biotic interactions play pivotal roles in shaping the physiological responses and survival strategies of microorganisms. This study investigates the effects of Gracilaria bailinae on photosynthesis and metabolism on the diatom Phaeodactylum tricornutum and the ecological significance. Our results reveal considerable suppression by G. bailinae on both its light-dependent and light-independent reactions of photosynthesis in P. tricornutum. A pronounced decline in carbon fixation was observed causing. the diatom to prioritize its carbon flux towards carbohydrate synthesis for its cellular energy needs. At high G. bailinae concentrations a marked reduction in lipid content indicated their importance as emergency energy sources. This response in lipid mobilization under photosynthetic stress is an evolutionary strategy for environmental adaptation. In addition, G. bailinae-induced stress amplified lysosomal activity in the diatom. Such an upsurge in oxidative stress appears to fast-track cellular death. We conclude that the ROS production, induced by G. bailinae, acts as a linchpin in mediating stress responses, thereby significantly reconfiguring the metabolism in the diatom. This study not only elucidates the physiological countermeasures of microalgae against biotic stressors but it also underscores the complex interactions between aquatic microorganisms.</p>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"106861"},"PeriodicalIF":3.0,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142822235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-27DOI: 10.1016/j.marenvres.2024.106873
Jingjing Sha , Xudong Liu , Hui Wang , Xiaoli Song , Mengmeng Bao , Qingyun Yu , Guoyi Wen , Miao Wei
Seagrass beds serve crucial ecological functions, yet they are facing a severe decline necessitating immediate conservation and restoration efforts. Current assessments of seagrass habitat suitability are insufficient, thus hindering the restoration effects. This study used a combination of field surveys and satellite remote sensing to conduct a three-year monitoring of typical temperate seagrass beds in the Caofeidian and Xingcheng areas of the Bohai Sea. The relationships between seagrass community factors and environmental factors were investigated using Spearman correlation analysis, BIOENV analysis, and redundancy analysis (RDA). Subsequently, the weights of each environmental factor were determined using the Analytic Hierarchy Process (AHP), leading to the development of the Habitat Suitability Index (HSI). Seagrass habitat suitability maps for Caofeidian and Xingcheng areas were then generated using Geographic Information System (GIS). The results indicate that both seagrass ecosystems degraded during the study period, which coincided with a decreasing trend in habitat suitability shown by the suitability maps. This study provides a methodology for seagrass bed habitat suitability assessment, thereby contributing to the conservation and restoration of these vital ecosystems.
{"title":"Status and habitat suitability evaluation: A case study of the typical temperate seagrass beds in the Bohai Sea, China","authors":"Jingjing Sha , Xudong Liu , Hui Wang , Xiaoli Song , Mengmeng Bao , Qingyun Yu , Guoyi Wen , Miao Wei","doi":"10.1016/j.marenvres.2024.106873","DOIUrl":"10.1016/j.marenvres.2024.106873","url":null,"abstract":"<div><div>Seagrass beds serve crucial ecological functions, yet they are facing a severe decline necessitating immediate conservation and restoration efforts. Current assessments of seagrass habitat suitability are insufficient, thus hindering the restoration effects. This study used a combination of field surveys and satellite remote sensing to conduct a three-year monitoring of typical temperate seagrass beds in the Caofeidian and Xingcheng areas of the Bohai Sea. The relationships between seagrass community factors and environmental factors were investigated using Spearman correlation analysis, BIOENV analysis, and redundancy analysis (RDA). Subsequently, the weights of each environmental factor were determined using the Analytic Hierarchy Process (AHP), leading to the development of the Habitat Suitability Index (HSI). Seagrass habitat suitability maps for Caofeidian and Xingcheng areas were then generated using Geographic Information System (GIS). The results indicate that both seagrass ecosystems degraded during the study period, which coincided with a decreasing trend in habitat suitability shown by the suitability maps. This study provides a methodology for seagrass bed habitat suitability assessment, thereby contributing to the conservation and restoration of these vital ecosystems.</div></div>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"Article 106873"},"PeriodicalIF":3.0,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A better understanding of bacterial communities and the factors that drive them is essential to maintain their functions and services. As an ecosystem closely linked to human activities, the health of offshore aquaculture depends on the diversity and functions of bacteria in its environment. However, little attention has been paid to the vertical interface of the offshore aquaculture areas with shellfish net cages. In this study, high-throughput sequencing was used to analyze bacterial communities in different water layers of a net cage scallop farm in the offshore area of Northeast of China. Based on the results, an increased richness of bacterial communities was observed in the water adjacent to the net cages. Meanwhile, apparently different bacterial community compositions were observed among the water layers, with an enrichment of Cyanobacteria, Bacteroidota, and Firmicutes in the water layers above, parallel to, and below the net cages, respectively. According to the predicted functions, the bacterial communities of the water layers above, parallel to, and below the net cages were identified as phototrophy-, chemoheterotrophy-, and nitrogen respiration-dominated. Furthermore, network analysis revealed a complex but unstable bacterial community in the water layer containing the net cage. Finally, partial least squares path modelling revealed that the net cage aquaculture directly influenced the environmental variables and bacterial richness, which further induced the variations in bacterial community composition, and ultimately affected their ecological functions. These results provide a basic understanding of bacterial communities in net cage scallop farms and highlight the effects of offshore aquaculture on variations in ecological functions.
{"title":"Net cage aquaculture alters the co-occurrence network and functions of bacterial communities in offshore areas","authors":"Xiaoyan Guan , Zelong Zhao , Jingwei Jiang, Yongjia Pan, Shan Gao, Bai Wang, Zhong Chen, Xuda Wang, Hongjuan Sun, Bing Jiang, Ying Dong, Zunchun Zhou","doi":"10.1016/j.marenvres.2024.106872","DOIUrl":"10.1016/j.marenvres.2024.106872","url":null,"abstract":"<div><div>A better understanding of bacterial communities and the factors that drive them is essential to maintain their functions and services. As an ecosystem closely linked to human activities, the health of offshore aquaculture depends on the diversity and functions of bacteria in its environment. However, little attention has been paid to the vertical interface of the offshore aquaculture areas with shellfish net cages. In this study, high-throughput sequencing was used to analyze bacterial communities in different water layers of a net cage scallop farm in the offshore area of Northeast of China. Based on the results, an increased richness of bacterial communities was observed in the water adjacent to the net cages. Meanwhile, apparently different bacterial community compositions were observed among the water layers, with an enrichment of Cyanobacteria, Bacteroidota, and Firmicutes in the water layers above, parallel to, and below the net cages, respectively. According to the predicted functions, the bacterial communities of the water layers above, parallel to, and below the net cages were identified as phototrophy-, chemoheterotrophy-, and nitrogen respiration-dominated. Furthermore, network analysis revealed a complex but unstable bacterial community in the water layer containing the net cage. Finally, partial least squares path modelling revealed that the net cage aquaculture directly influenced the environmental variables and bacterial richness, which further induced the variations in bacterial community composition, and ultimately affected their ecological functions. These results provide a basic understanding of bacterial communities in net cage scallop farms and highlight the effects of offshore aquaculture on variations in ecological functions.</div></div>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"Article 106872"},"PeriodicalIF":3.0,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Marine heatwaves (MHWs) have become more frequent and intense in the context of rapid climate change, causing detrimental effects on marine bivalves and ecosystems they sustain. While selective breeding programs for bivalves can substantially enhance growth performance, their ability to improve thermal stress tolerance remains largely unexplored. Here, we compared physiological energetics of wild and selectively bred Hongkong oysters (Guihao No. 1) under intensifying MHWs conditions. Following two consecutive events of MHWs, selectively bred oysters exhibited around 10% higher survival rate than that of wild oysters. Throughout the course of the experiment, the clearance rate of selectively bred oysters was significantly increased in comparison to wild oysters showing significantly depressed ability to feed. Nevertheless, exposure of selectively bred oysters to MHWs elicited significantly increased oxygen assumption and ammonia excretion rates, which in turn enhanced their O:N ratio. When couched into energetic terms, while MHWs inhibited the individual scope for growth, selectively bred oysters displayed better thermal tolerance than wild oysters. Taken together, our findings highlight the potential of new varieties of selectively bred oysters (such as Guihao No. 2) in coping with intensifying MHWs and guide the future development of selective breeding strategies to enhance the oyster thermal resilience in this era of unprecedented climate change.
{"title":"Physiological energetics of selectively bred oysters (Crassostrea hongkongensis) under marine heatwaves","authors":"Xiaoyan Jiang , Xingzhi Zhang , Junliang Guan , Pingping He , Pingyuan Wei , Li Zhang , Jinxia Peng , Liqiang Zhao","doi":"10.1016/j.marenvres.2024.106871","DOIUrl":"10.1016/j.marenvres.2024.106871","url":null,"abstract":"<div><div>Marine heatwaves (MHWs) have become more frequent and intense in the context of rapid climate change, causing detrimental effects on marine bivalves and ecosystems they sustain. While selective breeding programs for bivalves can substantially enhance growth performance, their ability to improve thermal stress tolerance remains largely unexplored. Here, we compared physiological energetics of wild and selectively bred Hongkong oysters (Guihao No. 1) under intensifying MHWs conditions. Following two consecutive events of MHWs, selectively bred oysters exhibited around 10% higher survival rate than that of wild oysters. Throughout the course of the experiment, the clearance rate of selectively bred oysters was significantly increased in comparison to wild oysters showing significantly depressed ability to feed. Nevertheless, exposure of selectively bred oysters to MHWs elicited significantly increased oxygen assumption and ammonia excretion rates, which in turn enhanced their O:N ratio. When couched into energetic terms, while MHWs inhibited the individual scope for growth, selectively bred oysters displayed better thermal tolerance than wild oysters. Taken together, our findings highlight the potential of new varieties of selectively bred oysters (such as Guihao No. 2) in coping with intensifying MHWs and guide the future development of selective breeding strategies to enhance the oyster thermal resilience in this era of unprecedented climate change.</div></div>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"Article 106871"},"PeriodicalIF":3.0,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Global climate change has led to more frequent extreme temperature (extreme heat and cold) events, posing a serious threat to coral reef ecosystems. Higher latitudes are considered potential refuges for reef-building corals, but their response to extreme temperature stress in these regions remain unclear. This study, indoor simulated stress experiments ranging on Porites lutea from Weizhou Island in the northern part of the South China Sea, simulating suitable (26 °C) to extreme high (34 °C) and extreme low (12 °C) temperatures. Physiological, biochemical, and transcriptional responses, were analysed. Results showed P. lutea's tentacles contracted, and symbiotic relationships broke down at both high and low temperatures; leading to oxidative stress, and a higher risk of disease. The coral host's response to temperature stress was positively regulated, mainly through apoptosis and metabolic inhibition pathways, whereas Symbiodiniaceae C15 showed no significant response to either high- or low-temperature stress. The coral host played a dominant role in the holobiont's stress response, using similar mechanisms for both high- and low-temperatures with some differences in the details. This study enhances understanding the temperature response mechanisms of the dominant coral species, P. lutea in the relatively high-latitude regions of the South China Sea.
{"title":"High- and low-temperature stress responses of Porites lutea from the relatively high-latitude region of the South China Sea","authors":"Wen Huang , Zhihua Huang , Enguang Yang , Linqing Meng , Jinlian Chen , Ronghua Tan , Zunyong Xiao , Yupeng Zhou , Mingpei Xu , Kefu Yu","doi":"10.1016/j.marenvres.2024.106858","DOIUrl":"10.1016/j.marenvres.2024.106858","url":null,"abstract":"<div><div>Global climate change has led to more frequent extreme temperature (extreme heat and cold) events, posing a serious threat to coral reef ecosystems. Higher latitudes are considered potential refuges for reef-building corals, but their response to extreme temperature stress in these regions remain unclear. This study, indoor simulated stress experiments ranging on <em>Porites lutea</em> from Weizhou Island in the northern part of the South China Sea, simulating suitable (26 °C) to extreme high (34 °C) and extreme low (12 °C) temperatures. Physiological, biochemical, and transcriptional responses, were analysed. Results showed <em>P. lutea'</em>s tentacles contracted, and symbiotic relationships broke down at both high and low temperatures; leading to oxidative stress, and a higher risk of disease. The coral host's response to temperature stress was positively regulated, mainly through apoptosis and metabolic inhibition pathways, whereas Symbiodiniaceae C15 showed no significant response to either high- or low-temperature stress. The coral host played a dominant role in the holobiont's stress response, using similar mechanisms for both high- and low-temperatures with some differences in the details. This study enhances understanding the temperature response mechanisms of the dominant coral species, <em>P. lutea</em> in the relatively high-latitude regions of the South China Sea.</div></div>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"Article 106858"},"PeriodicalIF":3.0,"publicationDate":"2024-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-24DOI: 10.1016/j.marenvres.2024.106866
Daiane Aviz, Renata Souza de Barros, Raphael Simão de Faria, Roseanne Figueira da Silva, Jose Souto Rosa Filho
Despite their ecological importance, there has been insufficient investigation of reefs constructed by polychaetes of the family Sabellariidae in tropical regions. The present study compared macrofauna associated with Amazonian Sabellaria wilsoni reefs with focus on different morphologies (platform vs. hummock reefs) during distinct annual phases of structural development (preserved, eroded, and recuperation). The two types of reefs had dissimilar assemblages over the course of the structural phases. The platform reef had more muddy sediments and higher proportions of organic matter and phaeopigments, which favored soft-bottom infaunal groups, such as the polychaetes. The hummock reef had denser and taxonomically richer macrofauna, which was typical of consolidated substrates and dominated by crustaceans and bivalves. Temporal changes in the characteristics of the macrofauna were driven by physical disturbance of the reef morphology resulting from local increases in hydrodynamic intensity. The macrofauna associated with periods of reef growth (preserved and recuperation phases), which coincided with the rainy season, was less taxonomically rich in both reef types. In the erosion phase (in the dry season), degradation of the reef structure led to an increase in the complexity of the habitat and thus species richness. In the platform reef, erosion was accompanied by an increase in the density of the assemblage, while in the hummock reef, the density decreased. The present study offers important insights into the biodiversity and ecological function of this important marine habitat, as well as a baseline for future ecological research and the monitoring of tropical sabellariid reefs.
{"title":"Effects of the morphology and structural cycles of Sabellaria wilsoni Lana & Gruet, 1989 (Annelida: Sabellariidae) reefs on the associated macrofauna.","authors":"Daiane Aviz, Renata Souza de Barros, Raphael Simão de Faria, Roseanne Figueira da Silva, Jose Souto Rosa Filho","doi":"10.1016/j.marenvres.2024.106866","DOIUrl":"https://doi.org/10.1016/j.marenvres.2024.106866","url":null,"abstract":"<p><p>Despite their ecological importance, there has been insufficient investigation of reefs constructed by polychaetes of the family Sabellariidae in tropical regions. The present study compared macrofauna associated with Amazonian Sabellaria wilsoni reefs with focus on different morphologies (platform vs. hummock reefs) during distinct annual phases of structural development (preserved, eroded, and recuperation). The two types of reefs had dissimilar assemblages over the course of the structural phases. The platform reef had more muddy sediments and higher proportions of organic matter and phaeopigments, which favored soft-bottom infaunal groups, such as the polychaetes. The hummock reef had denser and taxonomically richer macrofauna, which was typical of consolidated substrates and dominated by crustaceans and bivalves. Temporal changes in the characteristics of the macrofauna were driven by physical disturbance of the reef morphology resulting from local increases in hydrodynamic intensity. The macrofauna associated with periods of reef growth (preserved and recuperation phases), which coincided with the rainy season, was less taxonomically rich in both reef types. In the erosion phase (in the dry season), degradation of the reef structure led to an increase in the complexity of the habitat and thus species richness. In the platform reef, erosion was accompanied by an increase in the density of the assemblage, while in the hummock reef, the density decreased. The present study offers important insights into the biodiversity and ecological function of this important marine habitat, as well as a baseline for future ecological research and the monitoring of tropical sabellariid reefs.</p>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"106866"},"PeriodicalIF":3.0,"publicationDate":"2024-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142813676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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