Marine environmental research最新文献

{"title":"Seasonal monitoring, ecological risk assessment, and prioritization of pharmaceuticals in a tropical semi-enclosed bay (Santos, São Paulo coast, Brazil)","authors":"Vinicius Roveri ,&nbsp;Luciana Lopes Guimarães ,&nbsp;Rafael Barreiros Kiyotani ,&nbsp;Wellington Rui Andrade de Assis Junior ,&nbsp;Ana Paula Metropolo ,&nbsp;Gilmar Aparecido dos Santos ,&nbsp;Aírton Zogaib Rodrigues ,&nbsp;Camilo Dias Seabra Pereira ,&nbsp;Alberto Teodorico Correia","doi":"10.1016/j.marenvres.2024.106889","DOIUrl":"10.1016/j.marenvres.2024.106889","url":null,"abstract":"<div><div>Research on the occurrence and seasonal monitoring of pharmaceutically active compounds (PhACs) in estuarine and coastal waters has intensified recently. However, few studies have been conducted with PhACs flowing into the marine waters of South America (such as Brazil). Against this backdrop, the aims of this study were: (i) evaluate, for the first time, the seasonal occurrence throughout a year and the potential ecological risks of ten selected PhACs in marine bathing waters from Santos Bay, São Paulo, Brazil (a tropical low-wave energy semi-closed bay); and (ii) develop a list of high-priority PhACs for the monitoring based on \"occurrence, persistence, bioaccumulation, and toxicity\" criteria (OPBT). Four water sampling campaigns were carried out throughout the four seasons of the year. The results showed that: (i) ten PhACs (namely, caffeine/CAF (87.20–567.23 ng/L); carbamazepine/CAR [below the limit of quantification (&lt;LOQ) to 3.42 ng/L]; citalopram/CIT (&lt;LOQ to 2.98 ng/L); acetaminophen/ACE (&lt;LOQ to 4.00 ng/L); diclofenac/DIC (&lt;LOQ to 5.17 ng/L); orphenadrine/ORP (&lt;LOQ to 3.92 ng/L); atenolol/ATE (&lt;LOQ to 2.98 ng/L); losartan/LOS (&lt;LOQ to 3.98 ng/L); enalapril/ENA (&lt;LOQ to 2.23 ng/L); and furosemide/FUR (&lt;LOQ to 3.24 ng/L), were found in Santos Bay; (ii) the \"mass gathering\" in Santos city during New Year holiday contributed significantly to increase the mass load of nine PhACs in marine waters; (iii) the ecological risk assessment revealed great environmental concern for the aquatic ecosystem, since the results suggest low to moderate risks of CAF, followed by LOS &gt; ACE &gt; DIC and CAR to algae, crustaceans, and fishes; (iv) Finally, regarding the OPBT ranking, the DIC was the highest-priority PhAC in Santos Bay, followed by: ORP &gt; LOS &gt; CIT &gt; CAR &gt; FUR &gt; ATE &gt; CAF &gt; ACE &gt; ENA.</div></div>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"Article 106889"},"PeriodicalIF":3.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142794501","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}

{"title":"Foraging in contrasting oceanographic regions impacts the fatty acid profile of two closely related pelagic seabirds","authors":"Maria I. Laranjeiro ,&nbsp;Tiago Simões ,&nbsp;Jaime A. Ramos ,&nbsp;Ivo dos Santos ,&nbsp;Jorge M. Pereira ,&nbsp;José M. Reyes-González ,&nbsp;Marco F.L. Lemos ,&nbsp;Vítor H. Paiva ,&nbsp;Sara C. Novais ,&nbsp;Joan Navarro ,&nbsp;Filipe R. Ceia","doi":"10.1016/j.marenvres.2024.106888","DOIUrl":"10.1016/j.marenvres.2024.106888","url":null,"abstract":"<div><div>Coastal urbanisation negatively affects marine ecosystems through habitat degradation and pollution. Cory's (<em>Calonectris borealis</em>) and Scopoli's (<em>C. diomedea</em>) shearwaters are closely related species inhabiting the Northeast Atlantic Ocean and the Mediterranean Sea, respectively. This study assesses the fatty acid profile, with the trophic and foraging ecology, of Cory's and Scopoli's shearwaters breeding at Berlenga (Atlantic Ocean) and Chafarinas (Mediterranean Sea) Islands. The diet quality of Scopoli's shearwaters is expected to be generally lower, characterised by reduced levels of ω-3 fatty acids. Additionally, higher concentrations of specific fatty acid trophic markers are anticipated, reflecting the Mediterranean's semi-enclosed environment, low productivity, and pollution challenges. These markers include oleic acid, vaccenic acid, <em>trans</em> fatty acids (indicative of urban and industrial discharges), and odd-chain fatty acids (indicative of bacterial presence). This study supported these predictions, with Scopoli's shearwaters foraging in the Mediterranean having higher concentrations of oleic and vaccenic acids, odd-chain fatty acids, and <em>trans</em>-palmitoleic acid in their plasma. Yet, concentrations of ω-3 were also higher in Scopoli's shearwaters. This may result from diverse prey availability and selection, and different habitat exploitation, partially supported by differences in the trophic ecology and foraging patterns of both species; or from an enhanced immunological basal response of Scopoli's shearwaters to cope with higher anthropogenic pressure in the western Mediterranean Sea. Further studies including specific diet and contaminant analyses are crucial to understand differences in fatty acid profiles of seabirds inhabiting both oceanic basins and the implications of diet quality for seabird populations.</div></div>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"Article 106888"},"PeriodicalIF":3.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142813678","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}

{"title":"Assessing spatial and temporal patterns of benthic bacterial communities in response to different sediment conditions.","authors":"Soraia Vieira, Helena Adão, Cláudia S L Vicente","doi":"10.1016/j.marenvres.2025.106963","DOIUrl":"https://doi.org/10.1016/j.marenvres.2025.106963","url":null,"abstract":"<p><p>Benthic bacterial communities are sensitive to habitat condition and present a fast response to environmental stressors, which makes them powerful ecological indicators of estuarine environments. The aim of this work is to study the spatial-temporal patterns of benthic bacterial communities in response to contrasting environmental conditions and assess their potential as ecological indicators of estuarine sediments. We characterized the diversity of bacterial communities in three contrasting sites on Sado Estuary (SW Coast, Portugal) and 4 sampling occasions, using 16S metagenomic approach. Based on previous studies, we hypothesized that diversity patterns of bacterial communities will be distinct between sites and across sampling occasions. Bacterial communities were more influenced by each site conditions than by temporal variations in the sediments. The main drivers of bacterial distribution were sediments' composition, organic contents, and hydrodynamic activity. This work provided an important baseline dataset from Sado estuary to explore bacterial networks concerning benthic ecosystem functioning.</p>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"106963"},"PeriodicalIF":3.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143374380","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}

{"title":"Multivariate statistical analysis of surface water quality in the capibaribe river (Pernambuco state, Northeast Brazil): Contributions to water management","authors":"Jaqueline dos Santos Silva ,&nbsp;Livia Caroline Alexandre de Araújo ,&nbsp;Milena Danda Vasconcelos ,&nbsp;Iago José Santos da Silva ,&nbsp;Fabricio Motteran ,&nbsp;Rosner Henrique Alves Rodrigues ,&nbsp;Carina Lucena Mendes-Marques ,&nbsp;Rayanna Barroso de Oliveira Alves ,&nbsp;Hernande Pereira da Silva ,&nbsp;Maria Paloma Barros ,&nbsp;Sivoneide Maria da Silva ,&nbsp;Guilherme Malafaia ,&nbsp;Carlos Alonso Leite dos Santos ,&nbsp;Henrique Douglas Melo Coutinho ,&nbsp;Maria Betânia Melo de Oliveira","doi":"10.1016/j.marenvres.2024.106876","DOIUrl":"10.1016/j.marenvres.2024.106876","url":null,"abstract":"<div><div>Assessing the quality of surface waters is essential for identifying changes in freshwater ecosystems and supporting the planning/proposing of measures to mitigate polluting sources. However, many studies involving the identification of pathogenic bacteria and/or their resistance profile to antimicrobial agents need a more holistic approach to conditioning or modulating factors. Thus, we apply different multivariate statistical techniques to the data set from the Capibaribe River's surface water, one of the most important in the Northeast of Brazil. Our data, taken together, suggest that the waters of the Capibaribe River have been suffering impacts associated with different human activities. Due to its flow crossing a large urban area, different sources are contributing to the contamination/pollution of its aquatic ecosystem, whose multivariate analysis allowed us to identify site-dependent characteristics that reflect the degree and type of human influence. The study of physical-chemical and chemical parameters reveals the influence of the high load of effluents (industrial and domestic) on the chemical and microbiological quality of the waters sampled at the SS4 site. On the other hand, the antimicrobial resistance profile of the isolates evaluated, especially at SS1, SS2, and SS3 sites, provides a comprehensive sample of the “resistome” present in the fecal content of thousands of people living in the region surrounding the Capibaribe River. The presence of enterobacteria in water indicates contamination of fecal origin. It represents a public health problem since the waters of the Capibaribe River can be a source of dissemination and persistence of bacteria resistant to humans and the environment. In conclusion, our study provides a more comprehensive understanding of the relationships between surface water, basic sanitation, antibiotic exposure, bacterial gene transfer, and human colonization, whether in the context of the region studied or other locations.</div></div>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"Article 106876"},"PeriodicalIF":3.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142791571","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}

{"title":"Predicted environmental concentration (PEC), environmental risk assessment (ERA) and prioritization of antiretroviral drugs (ARVs) in seawater from Guarujá (Brazilian coastal zone).","authors":"Leonardo Teixeira Ramos, Vinicius Roveri, Walber Toma, Rafael Barreiros Kiyotani, Wellington Rui Andrade de Assis Junior, Ana Paula Metropolo, Gilmar Aparecido Dos Santos, Aírton Zogaib Rodrigues, Luciana Lopes Guimarães","doi":"10.1016/j.marenvres.2025.106964","DOIUrl":"10.1016/j.marenvres.2025.106964","url":null,"abstract":"<p><p>The antiretroviral therapy program's success in managing the human immunodeficiency virus (HIV) has inadvertently led to the release of antiretrovirals (ARVs) into worldwide aquatic ecosystems. However, few studies investigated the risks of ARV loadings that flow continuously to the marine waters of South America (such as Brazil). Against this backdrop, the aims of this study were: (i) to estimate the Predicted Environmental Concentration (PEC) of thirteen ARVs worldwide used in HIV treatment, and which are frequently disposed of in the marine aquatic ecosystems of Guarujá, São Paulo coastline, Brazil.; (ii) predict, through the Environmental Risk Assessment (ERA), the potential acute and chronic risks of these ARVs; and (iii) create a prioritization list of the most hazardous ARVs, based on the intrinsic properties of these compounds, i.e.: occurrence (O); persistence (P), bioaccumulation (B) and toxicity (T) (OPBT criteria). The PEC calculations indicated that all the ARVs examined in this study require an assessment of their impact on aquatic organisms, as all results exceeded the limits set by the guidelines of the European Medicines Agency., i.e., the PEC ranged between 0.37 and 99.39 μg/L. The results of individual ERA showed the following trend: (i) 56.41% of the results of acute toxicity indicated high toxicity for the three trophic levels; 33.33% of the results indicated low risk for one of the trophic levels, and 10.26% indicated moderate toxicity, and (ii) in terms of chronic toxicity, 33.33% of the results indicated moderate risks, 35.90% indicated low or no risk, and 30.77% indicated high risks. Regarding the results of the mixture of ARVs, the ERA showed a high acute and/or chronic risk for all five classes tested, i.e., (i) nucleoside/nucleotide reverse transcriptase inhibitors; ii) non-nucleoside reverse transcriptase inhibitors; iii) protease inhibitors; (iv) integrase strand transfer inhibitors; and (v) chemokine receptor antagonists. Ultimately, the final ranking of the OPBT approach was etravirine (the highest-priority ARV in seawater from Guarujá), followed by: nevirapine > efavirenz > ritonavir > lopinavir > maraviroc > atazanavir > darunavir > abacavir > dolutegravir > zidovudine > tenofovir > lamivudine.</p>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"106964"},"PeriodicalIF":3.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143023797","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}

{"title":"The differential physiological responses to heat stress in the scleractinian coral Pocillopora damicornis are affected by its energy reserve.","authors":"Qiuyu Yu, Chunlong He, Yi Wang, Mingxun An, Kai Tang, Zhaoqun Liu, Zhi Zhou","doi":"10.1016/j.marenvres.2025.106966","DOIUrl":"10.1016/j.marenvres.2025.106966","url":null,"abstract":"<p><p>The scleractinian corals conduct various responses upon heat stress such as bleaching and tissue loss, and colonies from the same coral species can conduct differential physiological activities with the biochemical basis unknown. In the present study, factors that influence the heat stress responses in coral Pocillopora damicornis were investigated. It was observed that P. damicornis conducted three differential physiological responses under heat treatment including tissue loss, bleaching, and polyp bailout. During heat response process, coral colonies conducting tissue loss had significantly higher total antioxidant capacity (T-AOC) level, while the bleached coral colonies exhibited higher caspase-3 activation level. Moreover, the stress response varied based on the energy reserve status. Colonies with higher lipid and sugar reserves were more likely to bleach, while those with lower reserves tended to undergo polyp bailout. We demonstrate that energy reserves influence the heat response patterns of P. damicornis. Colonies with higher lipid and sugar reserves may survive longer under heat stress, suggesting that these energy reserves contribute to their heat resistance. This study suggests that colonies with higher energy reserves prior to thermal stress may have greater thermal resistance, indicating that long-term environmental stressors that deplete energy reserves could increase susceptibility to thermal stress.</p>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"106966"},"PeriodicalIF":3.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143047024","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}

{"title":"Enhanced crude oil degradation observed in sea ice following bioaugmentation with arctic bacteria","authors":"Diana Saltymakova ,&nbsp;Durell S. Desmond ,&nbsp;Alastair F. Smith ,&nbsp;María A. Bautista ,&nbsp;Eric Collins ,&nbsp;Katarzyna Polcwiartek ,&nbsp;Nolan Snyder ,&nbsp;Teresinha Wolfe ,&nbsp;Casey Hubert ,&nbsp;Dustin Isleifson ,&nbsp;Gary Stern","doi":"10.1016/j.marenvres.2024.106942","DOIUrl":"10.1016/j.marenvres.2024.106942","url":null,"abstract":"<div><div>Petroleum-derived contamination is a growing hazard for the Arctic Ocean and northern marine transportation corridors. In northern settings where the accessibility to oil spills can be limited, natural attenuation is the most promising remediation process. The goal of the presented research is to evaluate the impact of biodegradation on crude oil inside sea ice. To this end, a bioremediation experiment was conducted at the Sea-ice Environmental Research Facility, University of Manitoba. The experiment utilized two mesocosm tanks (Augmented and Native) filled with nutrient-enriched artificial seawater (i.e., biostimulation). The water in the Augmented tank also contained oil-acclimated bacteria enriched from Arctic surface seawater from Cambridge Bay, Canada (i.e., bioaugmentation). The Native tank was not inoculated, but both tanks contained a bacterial community originating with the artificial seawater preparation. Crude oil was added under the naturally formed ice cover within each tank, creating areas that contained different oil concentrations. The Augmented tank contained 22 distinct bacterial genera compared to the Native tank, presumably due to the inoculation. The abundance of distinct bacterial genera was maximal in the water column and in low-contaminated ice core samples (&lt;0.21 g oil/L). In these ice cores, bioaugmentation affected the concentration of low-molecular-weight aliphatic compounds (&lt;C₁₈) and naphthalenes (&lt;C₅). We also observed a 1% loss per day of n-nonadecane, n-docosane, methylphenanthrene, and tetramethylnaphthalene in the Augmented tank, which we attribute to bioaugmentation by the Arctic bacterial enrichment. In contrast, losses of these same compounds plateaued after day 15 in the Native tank.</div></div>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"Article 106942"},"PeriodicalIF":3.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142965543","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}

{"title":"Gradient experiment reveals physiological stress from heavy metal zinc on the economically valuable seaweed Sargassum fusiforme","authors":"Yiqi Kuang ,&nbsp;Donya Bao ,&nbsp;Xingda Sheng ,&nbsp;Congquan Gao ,&nbsp;Guanfeng Pang ,&nbsp;Lina Guo ,&nbsp;Binbin Chen ,&nbsp;Zenglin Ma","doi":"10.1016/j.marenvres.2025.106958","DOIUrl":"10.1016/j.marenvres.2025.106958","url":null,"abstract":"<div><div>Zn is a common heavy metal pollutant in water bodies and accounts for the largest proportion of heavy metal pollutants in many rivers entering the sea. This study investigated the growth and physiological response characteristics of <em>Sargassum fusiforme</em> under different divalent Zn ion concentration gradients. We observed that low concentration Zn²⁺ treatment (&lt;2 mg L⁻¹) exerted no significant effect on the growth rate, photosynthesis, and nitrogen metabolism-related indicators of <em>S. fusiforme</em>. Treatment with medium to high Zn²⁺ concentrations (2–25 mg L⁻¹) significantly affected the growth rate, photosynthetic activity, nitrogen absorption rate, antioxidant enzyme activity, membrane lipids, and DNA peroxidation damage-related indicators of <em>S. fusiforme</em>. Under medium-to-high concentration treatments, the SOD activity of <em>S. fusiforme</em> decreased with increasing concentration, and the CAT activity increased with increasing treatment concentration. The MDA and H₂O₂ contents increased with increasing Zn²⁺ concentrations. At a Zn²⁺ concentration of 5 mg L⁻¹, the relative conductivity of <em>S. fusiforme</em> significantly increased. Treatment with higher Zn²⁺ concentrations significantly increased the 8-hydroxydeoxyguanosine (8-OHdG) content, poly ADP-ribose polymerase (PARP) activity, and Histone H2AX content of <em>S. fusiforme</em>, thus indicating that Zn²⁺ stress causes DNA damage. All Zn²⁺ concentrations induced mannitol accumulation, and soluble protein content decreased with increasing Zn²⁺ concentration. In summary, we observed that a Zn²⁺ concentration of 2–5 mg L⁻¹ may be the critical value for the response of <em>S. fusiforme</em> to Zn²⁺ stress. Higher concentrations of Zn in the environment can exert toxic effects on the growth, development, and biomass accumulation of <em>S. fusiforme</em>. This study provides a reference for the risk assessment and aquaculture management of seaweeds.</div></div>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"Article 106958"},"PeriodicalIF":3.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142971562","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}

{"title":"Regulation of desiccation-immersion cycle on the rate and fate of dissolved organic carbon release by Ulva pertusa","authors":"Luyao Wang ,&nbsp;Chengxiang Peng ,&nbsp;Zhengyi Liu ,&nbsp;Xiaoli Zhang ,&nbsp;Zhaokun Xu ,&nbsp;Zhiyuan Liu ,&nbsp;Jinhuan Hu ,&nbsp;Song Qin ,&nbsp;Zhihai Zhong","doi":"10.1016/j.marenvres.2024.106943","DOIUrl":"10.1016/j.marenvres.2024.106943","url":null,"abstract":"<div><div>Macroalgae widely distribute in intertidal zones, one of blue carbon organisms. However, the regulatory mechanisms of tide on the carbon sequestration of macroalgae are still unclear. This study explored the effects of desiccation-rewetting cycles induced by tide on dissolved organic carbon (DOC) release from <em>Ulva pertusa</em>, which is prevalent from high to low tidal zones. Results showed that during desiccation stage, the DOC release of <em>U. pertusa</em> varied with desiccation levels, releasing 0.082, 0.22, and 0.35 mg g⁻¹ FW at 0%, 40%, and 80% water loss, respectively, DOC accumulated on the surface of <em>U. pertusa</em> at a rate of about 0.52 mg g⁻¹ FW h⁻¹. Following 4 h of rewetting, DOC released surges to 0.99, 2.51, and 2.10 mg g⁻¹ FW h⁻¹. Using a stable isotope (¹³C) tracer method, we found that most DOC released by <em>U. pertusa</em> come from early fixed carbon. At 40% water loss, partial DOC stemmed from newly fixed carbon. DOC composition varied with desiccation level, affecting its bioavailability. After 16 days of degradation, DOC concentrations from <em>U. pertusa</em> at 0%, 40%, and 80% desiccation were 1.99, 3.22, and 2.54 mg g⁻¹ FW, respectively. The 80% water loss showed the highest degradation rate, while the non-water-loss treatment group had the most potential to form refractory DOC. This study underlines the complex relationship between tide and the dynamics of DOC release in <em>U. pertusa</em>, highlighting their role in coastal carbon cycling.</div></div>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"Article 106943"},"PeriodicalIF":3.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142927469","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}

{"title":"Temporal variability in mortality and recruitment jointly influence the periodic fluctuations in Antarctic krill populations","authors":"Sisong Dong ,&nbsp;Fan Zhang ,&nbsp;Guoping Zhu","doi":"10.1016/j.marenvres.2024.106923","DOIUrl":"10.1016/j.marenvres.2024.106923","url":null,"abstract":"<div><div>Antarctic krill (<em>Euphausia superba</em>) is a key part of the food web in the Southern Ocean ecosystem. Significant inter-annual fluctuations in population dynamics make stock assessment and management of its population a significant challenge. To better understand the population dynamics and fluctuation of krill, a survey-based age-structured catch-at-length model (ACL) is used to estimate the periodic fluctuations, based on length data collected from scientific surveys under the US Antarctic Marine Living Resources (AMLR) Program between 1992 and 2011. Spectral analysis of the model estimates revealed periodic fluctuations of 5–6 years in the recruitment, total abundance, and total biomass of krill in the Antarctic Peninsula, while spawning stock biomass exhibited periodic fluctuations of both 5–6 years and 2–3 years. The variations in krill total abundance and total biomass were mainly driven by recruitment, but the variation in spawning stock biomass was likely driven by both recruitment and time-varying, age-specific mortality. Our study contributes to a better understanding of the patterns and drivers of the periodic dynamics of Antarctic krill, which may help lead to improved assessments and fishery management for this important stock.</div></div>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"204 ","pages":"Article 106923"},"PeriodicalIF":3.0,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142895841","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}