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Marine litter abundance and distribution on beaches on the Isle of Rügen considering the influence of exposition, morphology and recreational activities
2017
Hengstmann, Elena | Gräwe, Dennis | Tamminga, Matthias | Fischer, Elke Kerstin
The abundance, weight and composition of marine debris were determined at the northwest coast of the Isle of Rügen in 2015. A total number of 1115 macrolitter items were registered, resulting in an abundance of 304±88.96 items per 100m of beach length and therefore being greater than the abundances found for other beaches at the Baltic Sea. Macrolitter items were predominantly composed of plastic, on average 83%. The four beaches under investigation have different exposition as well as touristic levels. The differing influence of wind and water currents as well as recreational activities on the macrolitter at these beaches was detectable. The distribution of items within a beach segment was analyzed by implementing D-GPS and drone aerial photography. The results of this analysis suggested that the identity of the substrate as well as the presence of vegetation are both major influencing factors in the macrolitter distribution.
显示更多 [+] 显示较少 [-]Seasonal variation, flux estimation, and source analysis of dissolved emerging organic contaminants in the Yangtze Estuary, China
2017
Zhao, Heng | Cao, Zhen | Liu, Xue | Zhan, Yi | Zhang, Jing | Xiao, Xi | Yang, Yi | Zhou, Junliang | Xu, Jiang
The occurrence and seasonal variation of 24 dissolved emerging organic contaminants in the Yangtze Estuary were studied, including 12 non-antibiotic pharmaceuticals, seven sulfonamides, two macrolides and three chloramphenicols. Sulfadiazine, erythromycin, thiamphenicol and paracetamol were the primary contaminants in sulfonamides, macrolides, chloramphenicols and non-antibiotic pharmaceutical groups, respectively. Compared to the concentrations at Datong, chloramphenicols at Xuliujing were significantly higher in autumn and winter, while macrolides were lower in spring. Based on the flux estimation, approximately 37.1 tons of sulfonamides, 17.4 tons of macrolides, 79.2 tons of chloramphenicols and 14.1 tons of non-antibiotic pharmaceuticals were discharged into the Yangtze Estuary from June 2013 to May 2014. However, the total flux from the Huangpu River only represented 5% of the total. The pharmaceutical sources were speculated on by analyzing the seasonal variations in pharmaceutical concentrations and fluxes at various sites. Both environmental and social factors might affect the fluxes.
显示更多 [+] 显示较少 [-]Seasonal antioxidant responses in the sea urchin Paracentrotus lividus (Lamarck 1816) used as a bioindicator of the environmental contamination in the South-East Mediterranean
2017
Amri, Sandra | Samar, Mohamed-Faouzi | Sellem, Fériel | Ouali, Kheireddine
In this study, sea urchin Paracentrotus lividus were sampled seasonally at three stations during 2012 in the coastal areas of the Gulf of Annaba (southeast Mediterranean). For all sea urchins, the gonad index was calculated to determine sea urchin reproductive status. Moreover, a set of biochemical parameters, including biomarkers and oxidative stress parameters, was measured in gonads. The pesticides and physiochemical parameters were measured and dosed in sea water.The results obtained highlighted that the levels of pesticide were generally low and below those commonly applied by environmental quality standards (EQS), indicating that no alarm state is currently present in the Gulf of Annaba. In addition to pollution, seasonal change is an important factor influencing biomarker activity, and the significant increases in biomarker levels in spring are a major observed trend. This activity may also be related to reproductive status. Seasonal variability was confirmed by the significant results of the Kruskal-Wallis test and by the high degree of divergence between seasons in PCA, with a total of 83.83% of variance explained.These results indicate that environmental factors that vary seasonally may affect the antioxidant status of the sea urchin Paracentrotus lividus.
显示更多 [+] 显示较少 [-]Paralytic shellfish toxins in phytoplankton and shellfish samples collected from the Bohai Sea, China
2017
Liu, Yang | Yu, Ren-Cheng | Kong, Fan-Zhou | Chen, Zhen-Fan | Dai, Li | Gao, Yan | Zhang, Qing-Chun | Wang, Yunfeng | Yan, Tian | Zhou, Ming-Jiang
Phytoplankton and shellfish samples collected periodically from 5 representative mariculture zones around the Bohai Sea, Laishan (LS), Laizhou (LZ), Hangu (HG), Qinhuangdao (QHD) and Huludao (HLD), were analysed for paralytic shellfish toxins (PSTs) using an high-performance liquid chromatography (HPLC) method. Toxins were detected in 13 out of 20 phytoplankton samples, and N-sulfocarbamoyl toxins (C1/2) were predominant components of PSTs in phytoplankton samples with relatively low toxin content. However, two phytoplankton samples with high PST content collected from QHD and LS had unique toxin profiles characterized by high-potency carbamoyl toxins (GTX1/4) and decarbamoyl toxins (dcGTX2/3 and dcSTX), respectively. PSTs were commonly found in shellfish samples, and toxin content ranged from 0 to 27.6nmol/g. High level of PSTs were often found in scallops and clams. Shellfish from QHD in spring, and LZ and LS in autumn exhibited high risks of PST contamination.
显示更多 [+] 显示较少 [-]Are seagrass beds indicators of anthropogenic nutrient stress in the rocky intertidal?
2017
Honig, Susanna E. | Mahoney, Brenna | Glanz, Jess S. | Hughes, Brent B.
It is well established that anthropogenic nutrient inputs harm estuarine seagrasses, but the influence of nutrients in rocky intertidal ecosystems is less clear. In this study, we investigated the effect of anthropogenic nutrient loading on Phyllospadix spp., a rocky intertidal seagrass, at local and regional scales. At sites along California, Washington, and Oregon, we demonstrated a significant, negative correlation of urban development and Phyllospadix bed thickness. These results were echoed locally along an urban gradient on the central California coast, where Phyllospadix shoot δ15N was negatively associated with Phyllospadix bed thickness, and experimentally, where nutrient additions in mesocosms reduced Phyllospadix shoot formation and increased epiphytic cover on Phyllospadix shoots. These findings provide evidence that coastal development can threaten rocky intertidal seagrasses through increased epiphytism. Considering that seagrasses provide vital ecosystem services, mitigating eutrophication and other factors associated with development in the rocky intertidal coastal zone should be a management priority.
显示更多 [+] 显示较少 [-]Assessment of metal concentrations (Cu, Zn, and Pb) in seawater, sediment and biota samples in the coastal area of Eastern Black Sea, Turkey
2017
Baltas, Hasan | Sirin, Murat | Dalgic, Goktug | Bayrak, Esra Yilmaz | Akdeniz, Aysel
This study investigated the contents of Cu, Zn and Pb in seawater, sediment, different shell sizes of mussel (Mytilus galloprovincialis) and sea snail (Rapana venosa) samples collected from four different provinces of the Eastern Black Sea Region. With the exception of Zn, all the metal concentration values measured in the sea snail were observed to be higher than those of mussels in all stations. While the correlation between mussels and sea snail according to metal concentrations was found to be positive (p˂0.05), this relation was not observed between the other parameters, such as the shell sizes, salinity and pH (p˃0.05). Although the mean concentration values of Cu, Zn, and Pb for mussel and sea snail are significantly above the tolerable levels, the estimated daily intake values for mussel were below the daily intake recommended.
显示更多 [+] 显示较少 [-]Source apportionment of PM2.5 pollution in an industrial city in southern China
2017
Zou, Bei-Bing | Huang, Xiao Feng | Dai, Jing | Zhang, Bin | Zeng, Li-Wu | Feng, Ning | He, Ling-Yan
Severe PM2.5 pollution has become a great challenge to atmospheric pollution control in China. Most of previous aerosol source apportionment studies in China focused only on part of PM2.5 (e.g., organic matter in composition or PM1 in size) or lacked source contributions identified with necessary tempo-spatial variations, which makes the results not convincible enough for policy making. In this study, five various sites were selected for simultaneous PM2.5 observation in an industrial city in the Pearl River Delta (PRD) of South China during all four seasons of 2014. A positive matrix factorization (PMF) model was applied to the datasets of measured chemical species to perform source apportionment with the results as: (1) The annual mean PM2.5 concentration was 52.6 μg/m³, with secondary sulfate, vehicle emissions, secondary organic aerosol (SOA), and secondary nitrate identified as the major sources, contributing 24.6%, 14.5%, 12.0%, and 10.9% to PM2.5, respectively. Ship emissions, fugitive dust, biomass combustion, industrial emissions, and aged sea salt each contributed 3%–8%. (2) The tempo-spatial variations of sources reveal that secondary sulfate, SOA, biomass combustion, and ship emissions had obvious regional pollution characteristics; however, vehicle emissions, secondary nitrate, fugitive dust, and industrial emissions showed obvious local emission characteristics. (3) The exceeding standard polluted days (PM2.5>75 μg/m³) appeared with secondary nitrate, biomass burning, and SOA increasing mostly in concentration, which should be controlled more strictly. This study highlights the importance of SOA in PM2.5 pollution in China, which has been scarcely quantified for bulk PM2.5 in the literature.
显示更多 [+] 显示较少 [-]The impact of two oil spill events on the water quality along coastal area of Kenting National Park, southern Taiwan
2017
Chen, Chung-Chi | Tew, Kwee Siong | Ho, Ping-Ho | Ko, Fung-Chi | Hsieh, Hung-Yen | Meng, Pei-Jie
In 2009, the container ship Colombo Queen and the oil tanker W-O BUDMO grounded off Jialeshui and Houwan, respectively, in southern Taiwan. Water quality was monitored at each site to evaluate the environmental impact caused by the resulting oil spills. The results show that the PAHs, turbidity, and other nutrients increased shortly after oil spill, however levels of these parameters eventually returned to baseline levels. On the other hand, DO saturation, pH and chl. a decreased initially, reached maxima after 10days, and returned to the baseline levels after 14days. The chl. a concentration, pH and DO saturation fluctuated in a similar pattern at both sites during the oil spills, likely driven by algal blooms. In this study, we documented a full environmental recovery at coastal areas before, during and after the oil spills.
显示更多 [+] 显示较少 [-]Mountains to the sea: River study of plastic and non-plastic microfiber pollution in the northeast USA
2017
Miller, Rachael Z. | Watts, Andrew J.R. | Winslow, Brooke O. | Galloway, Tamara S. | Barrows, Abigail P.W.
Aquatic environments are sinks for anthropogenic contamination, whether chemical or solid pollutants. Microfibers shed from clothing and other textiles contribute to this problem. These can be plastic or non-plastic origin. Our aim was to investigate the presence and distribution of both types of anthropogenic microfibers along the length of the Hudson River, USA. Surface grab samples were collected and filtered through a 0.45μm filter paper. Abundance of fibers was determined after subtraction of potential contamination. 233 microfibers were recorded in 142 samples, averaging 0.98microfibersL−1. Subsequent micro-FTIR showed half of the fibers were plastic while the other half were non-plastic, but of anthropogenic origin. There was no relationship between fiber abundance, wastewater treatment plant location or population density. Extrapolating from this data, and using available hydrographic data, 34.4% of the Hudson River's watershed drainage area contributes an average 300 million anthropogenic microfibers into the Atlantic Ocean per day.
显示更多 [+] 显示较少 [-]Size and dynamics of microplastic in gastrointestinal tracts of Northern Fulmars (Fulmarus glacialis) and Sooty Shearwaters (Ardenna grisea)
2017
Terepocki, Alicia K. | Brush, Alex T. | Kleine, Lydia U. | Shugart, Gary W. | Hodum, Peter
We found microplastic in 89.5% of 143 Northern Fulmars from 2008 to 2013 and 64% of 25 Sooty Shearwaters in 2011–2012 that were found dead or stranded on Oregon and Washington beaches. Average plastic loads were 19.5 pieces and 0.461g for fulmars and 13.3 pieces and 0.335g for shearwaters. Pre-manufactured plastic pellets accounted for 8.5% of fulmar and 33% of shearwater plastic pieces. In both species, plastic in proventriculi averaged 2–3mm larger in greatest dimension than in ventriculi. Intestinal plastic in fulmars averaged 1mm less in greatest dimension than ventricular plastic. There was no significant reduction in pieces or mass of plastic in 33 fulmars held for a median of seven days in a plastic-free environment. Three fulmars that survived to be released from rehabilitation regurgitated plastic, which provided an alternative outlet for elimination of plastic and requires reassessment of the dynamics of plastic in seabird gastrointestinal tracts.
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