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Rapid expansion of Ulva blooms in the Yellow Sea, China through sexual reproduction and vegetative growth Full text
2018
Cui, Jianjun | Shi, Jinting | Zhang, Jianheng | Wang, Lintao | Fan, Shaoying | Xu, Zhenyang | Huo, Yuanzi | Zhou, Qiaoyun | Lu, Yuwei | He, Peimin
Green algal blooms have occurred in the Yellow Sea for 11 consecutive years since 2007. A “seed bank” comprising micro-propagules including gametes, meiospores, and zygotes, played an important role in the rapid formation of a green tide. In the present study, germination differences among zygotes, meiospores, and gametes were examined. The growth ability and maturation period of alternating generations of sexual Ulva prolifera strains were also assessed. The zygote and meiospore germination rate was 91.67% and 80.29%, respectively, approximately three times greater than that of gametes (30%). In addition, the highest daily growth rate of sporophytes and gametophytes was 266.7% and 288.1%, respectively, and the maturation period of sporophytes and gametophytes was 35.7 and 31.3 days, respectively. These results indicate that sexual reproduction and vegetative growth are mainly responsible for the rapid expansion of macroalgal blooms in the Yellow Sea.
Show more [+] Less [-]Bisphenol A and alkylphenols concentrations in selected mariculture fish species from Pulau Kukup, Johor, Malaysia Full text
2018
Ismail, Nur Afifah Hanun | Wee, Sze Yee | Ahmad Zaharin Aris,
Endocrine disrupting compound (EDC) contamination in food is a global concern. Concerning potential environmental and human health exposed to EDCs via food intake, an experiment was conducted on the selected EDCs concentration in the mariculture fish, Trachinotus blochii (golden pomfret), Lutjanus campechanus (snapper), and Lates calcarifer (sea bass) at Pulau Kukup, Johor. Mariculture activity at Pulau Kukup involves active export of fishes to Singapore and Indonesia. The recovery of BPA (bisphenol A), 4OP (4-octylphenol), and 4NP (4-nonylphenol) were 61.54%–93.00%, 16.79%–17.13%, and 61.24%–71.49%, respectively. Relatively high concentration of BPA was recorded in T. blochii (0.322ng/g), followed by L. calcarifer (0.124ng/g) and L. campechanus (0.023ng/g). Furthermore, 4OP and 4NP were detected only in T. blochii at concentrations of 0.084ng/g and 0.078ng/g, respectively. The results of the present study provide insights on monitoring and managing mariculture activity in relation to environmental protection and food safety.
Show more [+] Less [-]Assessing the effect of mercury pollution on cultured benthic foraminifera community using morphological and eDNA metabarcoding approaches Full text
2018
Frontalini, Fabrizio | Greco, Mattia | Di Bella, Letizia | Lejzerowicz, Franck | Reo, Emanuela | Caruso, Antonio | Cosentino, Claudia | Maccotta, Antonella | Scopelliti, Giovanna | Nardelli, Maria Pia | Losada, María Teresa | Armynot du Châtelet, Eric | Coccioni, R. | Pawlowski, Jan
Mercury (Hg) is a highly toxic element for living organisms and is known to bioaccumulate and biomagnify. Here, we analyze the response of benthic foraminifera communities cultured in mesocosm and exposed to different concentrations of Hg. Standard morphological analyses and environmental DNA metabarcoding show evidence that Hg pollution has detrimental effects on benthic foraminifera. The molecular analysis provides a more complete view of foraminiferal communities including the soft-walled single-chambered monothalamiids and small-sized hard-shelled rotaliids and textulariids than the morphological one. Among these taxa that are typically overlooked in morphological studies we found potential bioindicators of Hg pollution. The mesocosm approach proves to be an effective method to study benthic foraminiferal responses to various types and concentrations of pollutants over time. This study further supports foraminiferal metabarcoding as a complementary and/or alternative method to standard biomonitoring program based on the morphological identification of species communities.
Show more [+] Less [-]Exploration of microplastics from personal care and cosmetic products and its estimated emissions to marine environment: An evidence from Malaysia Full text
2018
Praveena, Sarva Mangala | Shaifuddin, Siti Norashikin Mohamad | Akizuki, Shinichi
This study aims understand microplastics from personal care and cosmetic products in Malaysia via quantification and characterization of microplastics together with emission estimation to marine environment. A total of 214 respondents from all over Malaysia were surveyed with identification of top ten personal care and cosmetic products usage. Particles found in facial cleaner/scrub and toothpaste were colored and colorless with majority of granular shapes. Particles in toothpaste were found between 3 and 145 μm while particles in facial cleaner/scrub were found to be between 10 and 178 μm, stipulating the presence of microplastics. Plastic polymers (LDPE and polypropylene) were found in all facial cleaner/scrub samples while only plastic polymers (LDPE) were present in toothpaste sample G. A total of 0.199 trillion microplastics are expected to be released annually to marine environment in Malaysia. Personal care and cosmetic products are seen as one of the microplastics sources for Malaysia and worldwide.
Show more [+] Less [-]Reasons for seagrass optimism: Local ecological knowledge confirms presence of dugongs Full text
2018
Cullen-Unsworth, Leanne C. | Jones, Benjamin L. | Seary, Rachel | Newman, Rhian | Unsworth, Richard K.F.
Dugongs (Dugong dugon) depend on seagrass meadows for food. As such seagrass and dugong conservation should go hand in hand. Assessing dugong populations is notoriously challenging. In the most resource dependent communities Local Ecological Knowledge (LEK) is generally high and can provide an alternative to the use of expensive ecological surveys to understand dugong populations and support associated resource management decisions. Residents of the Wakatobi National Park (WNP), SE Sulawesi, Indonesia are highly dependent on marine resources for livelihoods and correspondingly LEK is high. Here LEK documents the presence of D. dugon in the WNP and infers changes in population size. Interviews with local residents in 2012–2013 revealed 99 sightings of dugongs since 1942, 48 of which occurred between 2002 and 2012, with 79.82% of respondents having seen a dugong. Declines in the frequency of sightings within the lifetime of several respondents were reported, respondents speculating that populations are reduced. This information can guide further cooperative research and conservation efforts for the protection of a vulnerable species and the seagrass habitat on which it depends.
Show more [+] Less [-]Effects of corresponding and non-corresponding contaminants on the fate of sulfonamide and quinolone resistance genes in the Laizhou Bay, China Full text
2018
Li, Qianwei | Na, Guangshui | Zhang, Linxiao | Lu, Zihao | Gao, Hui | Li, Ruijing | Jin, Shuaichen
The environmental behaviors and migration patterns of antibiotic resistance genes (ARGs) have attracted considerable research interest. However, there has been little research concerning the effects of corresponding and non-corresponding contaminants on the fate of ARGs in coastal environments. In the present study, the distribution of intI1, sul1, sul2, qnrS and aac(6′)-Ib were analyzed in water and sediment samples of Laizhou Bay in the context of corresponding and non-corresponding contaminants. The abundance of intI1, sul1 and sul2 genes exhibited a clear decreasing trend extending from the inner estuary to the coastal area. Strong and positive correlations existed between sul1/sul2 and sulfonamide antibiotic residues in sediments, and between the abundances of intI1 and sul1/sul2. Statistical analyses indicated that non-corresponding contaminants were partially correlated with ARG abundances. These results suggest that non-corresponding contaminants may have direct or indirect influences on the abundances of ARGs and intI1 in the Laizhou Bay.
Show more [+] Less [-]Fine sediment and particulate organic matter: A review and case study on ridge-to-reef transport, transformations, fates, and impacts on marine ecosystems Full text
2018
Bainbridge, Z. | Lewis, S. | Bartley, R. | Fabricius, K. | Collier, C. | Waterhouse, J. | Garzon-Garcia, A. | Robson, B. | Burton, J. | Wenger, A. | Brodie, J.
Studies documenting the effects of land-derived suspended particulate matter (SPM, i.e., particulate organic matter and mineral sediment) on marine ecosystems are typically disconnected from terrestrial studies that determine their origin, transport and fate. This study reviews sources, transport, transformations, fate and effects of SPM along the ‘ridge-to-reef’ continuum. We show that some of the SPM can be transported over long distances and transformed into large and easily resuspendible organic-rich sediment flocs. These flocs may lead to prolonged reductions in water clarity, impacting upon coral reef, seagrass and fish communities. Using the Great Barrier Reef (NE Australia) as a case study, we identify the latest research tools to determine thresholds of SPM exposure, allowing for an improved appreciation of marine risk. These tools are used to determine ecologically-relevant end-of-basin load targets and reliable marine water quality guidelines, thereby enabling enhanced prioritisation and management of SPM export from ridge-to-reef.
Show more [+] Less [-]Passive sampling monitoring of PAHs and trace metals in seawater during the salvaging of the Costa Concordia wreck (Parbuckling Project) Full text
2018
Schintu, Marco | Marrucci, Alessandro | Marras, Barbara | Atzori, Marco | Pellegrini, David
Passive sampling techniques were used for monitoring trace metals and polycyclic aromatic hydrocarbons (PAHs) in the seawater surrounding the Costa Concordia shipwreck (Isola del Giglio, Italy). The monitoring lasted two and a half years (2012–2014) and considered all four phases of the “parbuckling project”: stabilisation of the wreckage, installation of steel caissons on both sides of the wreck, parbuckling, and refloating. Dissolved trace metals (Cd, Cr, Cu, Hg, Ni, Pb, and V) were measured with diffusive gradients in thin films (DGT), while freely dissolved PAHs were measured with semi-permeable membrane devices (SPMDs). Passive sampling allowed to detect very low concentrations of contaminants, and indicated significant differences among the sampling stations and among the different steps for salvaging the wreck. The results suggested that the main source of contamination was the heavy working vessel traffic at the disaster site, rather than the release of contaminants from the wreck.
Show more [+] Less [-]The Gulfwatch contaminants monitoring program in the Gulf of Maine: Are its data being used for ocean protection, with special reference to Nova Scotia, Canada? Full text
2018
Chamberlain, Sarah D. | Wells, P. G. | MacDonald, Bertrum H.
The Gulfwatch Contaminants Monitoring Program is part of the Canada-US, Gulf of Maine Council on the Marine Environment (GOMC). Programs monitoring legacy toxic substances, i.e., chemical contaminants, such as Gulfwatch, collect and analyse environmental samples (e.g., blue mussels), interpret the data, and report on chemical levels and trends (spatial and temporal) in coastal waters. This study explored the extent to which its extensive information (data, reports, papers) has been used broadly and by Nova Scotia, a GOMC member. A mixed-methods study was conducted, using quantitative and qualitative metrics. Citations to some Gulfwatch papers and analysis of use of the Gulfwatch website showed that its data and information were accessed, mostly by government departments. However, interviews revealed that the departments were not using the data to inform Nova Scotia provincial coastal policy or practices. Recommendations are presented to improve the visibility and use of information provided by long-term, environmental monitoring programs.
Show more [+] Less [-]Antimicrobial resistance and pulsed-field gel electrophoresis typing of Vibrio parahaemolyticus isolated from shrimp mariculture environment along the east coast of China Full text
2018
Zhao, Shu | Ma, Licai | Wang, Yuan | Fu, Guihong | Zhou, Junfang | Li, Xincang | Fang, Wenhong
Environmental antimicrobial resistance (AMR) has drawn increasing attention due to its great risk to human health. The aim of this study was to investigate AMR and genotyping of Vibrio parahaemolyticus isolates (n = 114) recovered from shrimp mariculture environment in China. The isolates exhibited a high rate of resistance to streptomycin (78.9%), ampicillin (64.9%) and gentamicin (53.5%). Furthermore, multi-drug resistance was highly prevalent (61.4%), in which 95.9% of these ampicillin-resistant isolates were primarily mediated by blaCARB-17. Surprisingly, doxycylcine, florfenicol, and trimethoprim/sulfamethoxazole (TMP/SMZ) resistance genes occurred in susceptible isolates. Moreover, 114 isolates were grouped into unique pulsed field gel electrophoresis patterns. These findings suggest the need for the prudent use of antimicrobial agents on mariculture farms, in order to control the dissemination of antimicrobial resistant V. parahaemolyticus.
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