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Anthropogenic carbon as a basal resource in the benthic food webs in the Neva Estuary (Baltic Sea) Полный текст
2019
Golubkov, Sergey M. | Golubkov, Mikhail S. | Tiunov, Alexei V.
Organic pollution is a serious environmental problem for the coastal zones of seas. The study tested the hypothesis that allochthonous organic carbon derived from St. Petersburg wastewaters is a significant basal resource of carbon for the benthic food webs. We analyzed stable isotope composition of carbon and nitrogen in suspended organic matter in the Neva Estuary and in the tissues of macroinvertebrates and fish. The Stable Isotope Bayesian mixing model showed that waste waters were an important source of carbon for the most of consumers in the Neva Estuary. The autochthonous carbon produced by phytoplankton was a significant source of carbon only for some macroinvertebrates. The main consumers of the carbon derived from waste waters were tubificid worms, chironomid larvae and alien polychaete, which currently dominate in the zoobenthos of the estuary. These species replaced the former dominants, native crustaceans, which to a lesser extent use anthropogenic carbon.
Показать больше [+] Меньше [-]Endocrine and reproductive endpoints of Notothenia rossii and N. coriiceps: A baseline study for ecotoxicological monitoring in Antarctic waters Полный текст
2019
Ferreira, María Florencia | Lo Nostro, Fabiana | Honji, Renato | Ansaldo, Martin | Genovese, Griselda
Endocrine and reproductive endpoints of Notothenia rossii and N. coriiceps: A baseline study for ecotoxicological monitoring in Antarctic waters Полный текст
2019
Ferreira, María Florencia | Lo Nostro, Fabiana | Honji, Renato | Ansaldo, Martin | Genovese, Griselda
Pollution threats Antarctica and scientists blame xenobiotics and anthropic activities. Yet little is known about their effect on Antarctic ichthyofauna. Accordingly, we investigated the endocrine system of male fish Notothenia rossii and N. coriiceps (Perciformes, Nototheniidae) collected during Austral summer. For N. rossii, hormone levels of estradiol, testosterone, and 11-ketotestosterone were higher in fish collected during March than those of January; whereas for N. coriiceps estradiol and androgens levels were higher and lower in March, respectively. Histological analysis of the testes showed an unrestricted lobular type with no pathological alterations. However, detection of vitellogenin-like in plasma and skin mucus were seen in 75% of N. coriiceps males and 7% of N. rossii males. This is the first report of mucus vitellogenin-like detection as a non-invasive biomarker of endocrine disruption in notothenioid males and settles a baseline for future studies of reproductive biology and endocrine disruption in Antarctic fishes.
Показать больше [+] Меньше [-]Endocrine and reproductive endpoints of Notothenia rossii and N. coriiceps: A baseline study for ecotoxicological monitoring in Antarctic waters Полный текст
2019
Ferreira, María Florencia | Lo Nostro, Fabiana Laura | Honji, Renato Massaaki | Ansaldo, Martin | Genovese, Griselda
Pollution threats Antarctica and scientists blame xenobiotics and anthropic activities. Yet little is known about their effect on Antarctic ichthyofauna. Accordingly, we investigated the endocrine system of male fish Notothenia rossii and N. coriiceps (Perciformes, Nototheniidae) collected during Austral summer. For N. rossii, hormone levels of estradiol, testosterone, and 11-ketotestosterone were higher in fish collected during March than those of January; whereas for N. coriiceps estradiol and androgens levels were higher and lower in March, respectively. Histological analysis of the testes showed an unrestricted lobular type with no pathological alterations. However, detection of vitellogenin-like in plasma and skin mucus were seen in 75% of N. coriiceps males and 7% of N. rossii males. This is the first report of mucus vitellogenin-like detection as a non-invasive biomarker of endocrine disruption in notothenioid males and settles a baseline for future studies of reproductive biology and endocrine disruption in Antarctic fishes. | Fil: Ferreira, María Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental. Laboratorio de Ecotoxicología Acuática; Argentina | Fil: Lo Nostro, Fabiana Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental. Laboratorio de Ecotoxicología Acuática; Argentina | Fil: Honji, Renato Massaaki. Universidade de Sao Paulo; Brasil. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina | Fil: Ansaldo, Martin. Ministerio de Relaciones Exteriores, Comercio Interno y Culto. Dirección Nacional del Antártico. Instituto Antártico Argentino; Argentina | Fil: Genovese, Griselda. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental. Laboratorio de Ecotoxicología Acuática; Argentina
Показать больше [+] Меньше [-]Microplastic pollution on the Persian Gulf shoreline: A case study of Bandar Abbas city, Hormozgan Province, Iran Полный текст
2019
Nabizadeh, Ramin | Sajadi, Mojtaba | Rastkari, Noushin | Yaghmaeian, Kamyar
Microplastic particles (<5 mm), which are an emerging threat, are commonly found in marine ecosystems worldwide. This study investigated the effect of different types of coastal land use on microplastic frequency and distribution on the coastline of Bandar Abbas city; this study used a large sample compared to that used in other studies conducted in this region. The average number of microplastics was determined as 3252 ± 2766 microplastics/m² (±SD). ATR FT-IR spectroscopy showed that the dominant microplastic particles are expanded polystyrene, polyethylene terephthalate, polypropylene, and polyethylene. Statistical analysis showed a significant difference in microplastic contamination levels between the urban and nonuse beaches. This shows that heavily urbanized areas and human activities have significant effects on the dispersion and frequency of microplastics in the coastal areas of Bandar Abbas. Periodical coast-based cleanup and studies on microplastic pollution and their fluxes by comprehensive sampling are mostly recommended for the Persian Gulf coastline.
Показать больше [+] Меньше [-]Seagrass Posidonia oceanica diel pH fluctuations reduce the mortality of epiphytic forams under experimental ocean acidification Полный текст
2019
Ramajo, Laura | Lagos, Nelson A. | Duarte, Carlos M.
It is hypothesized that pH fluctuations produced by seagrasses metabolism may confer marine calcifiers resistance to ocean acidification. Here, we tested this thesis by comparing the net population growth rate (NPGR) of a foraminifer species (Rosalina sp.) epiphytic of Mediterranean seagrass (Posidonia oceanica) to average current and projected pH scenarios under either stable conditions or diel fluctuations in pH of 0.3 units; variations similar to that experienced in their habitat. No significant differences were found in NPGRs between the fluctuating and stable pH treatments at current pH levels. NPGRs in treatments where pH fluctuated did not present significant differences to the treatment with high and stable pH conditions. In contrast, foraminifers exposed to stable low pH regimes experienced a steep decline in NPGR. These results suggest that diel pH fluctuations generated by P. oceanica photosynthetic activity could confer resistance to ocean acidification to Rosalina sp.
Показать больше [+] Меньше [-]Damping of surface waves due to crude oil/oil emulsion films on water Полный текст
2019
Sergievskaya, Irina | Ermakov, Stanislav | Lazareva, Tatyana | Guo, Jie
In this paper results of laboratory studies of damping of gravity-capillary waves due to emulsified oil films (EOF) are presented and compared to crude oil films (COF). A laboratory method based on measuring the damping coefficient and the length of parametrically generated gravity-capillary waves is applied to a 50% EOF and to crude oil films. Measurements of wave damping were carried out in a range of surface wave lengths, corresponding to Bragg waves of X- to Ka-band radars. The obtained dependences of wave damping coefficient on EOF thickness have demonstrated the existence of a damping maximum at thicknesses of about 1–2 mm, and the maximum is approximately twice the one for COF, the damping maximum for EOF is located at larger film thicknesses than for COF. Theoretical calculations of wave damping have been performed and viscoelastic parameters of EOF have been estimated from comparison between theory and experiment.
Показать больше [+] Меньше [-]Understanding of Aerosol–Climate Interactions in China: Aerosol Impacts on Solar Radiation, Temperature, Cloud, and Precipitation and Its Changes Under Future Climate and Emission Scenarios Полный текст
2019
Liu, Song | Xing, Jia | Zhao, Bin | Wang, Jiandong | Wang, Shuxiao | Zhang, Xiaoye | Ding, Aijun
Fast growth of air pollution was experienced in China during the past decades, resulting in extremely large aerosol radiative forcing with up to ten times high compared to the global averages. The responses of surface air temperature to aerosol radiative effects range from − 0.1 to 1.1 K across China, with strong spatial and seasonal variations. Aerosol interaction with clouds can also affect radiation and precipitation. Under high pollution conditions, the frequency of heavy rain increases while the frequency of light rain decreases. Aerosols share common emission sources with CO₂, implying that reducing common sources can be another manifestation of the interaction between aerosol and climate. Air pollution controls will contribute to the climate change mitigation by reducing CO₂ emissions stemming from controls of pollution sources. On the other hand, potential co-benefits in reducing air pollution also come from the mitigation of climate change by reducing CO₂ emission that potentially affects the aerosol concentrations. It is suggested that the PM₂.₅ (fine particulate matter with an aerodynamic diameter of 2.5 μm or less) concentration tends to decrease under future climate control scenarios. Such co-benefits are mostly associated with the reduction of common sources of CO₂ and aerosol (noted as emission-driven interaction), rather than the variation of meteorological conditions associated with future climate change (noted as meteorology-driven interaction). Compared to emission-driven interaction, the impact by meteorology-driven interaction on aerosols is relatively smaller and varies geographically as the PM₂.₅ concentration is likely to increase in northern China while decrease in eastern China. The current review suggested that the co-benefits of reducing CO₂ and aerosol pollutant in China, and their response in the context of future climate change, are worthy of further research.
Показать больше [+] Меньше [-]Status of faecal pollution in ports: A basin-wide investigation in the Adriatic Sea Полный текст
2019
Luna, Gian Marco | Manini, Elena | Turk, Valentina | Tinta, Tinkara | D'Errico, Giuseppe | Baldrighi, Elisa | Baljak, Vanja | Buda, Donatella | Cabrini, Marina | Campanelli, Alessandra | Cenov, Arijana | Del Negro, Paola | Drakulović, Dragana | Fabbro, Cinzia | Glad, Marin | Grilec, Dolores | Grilli, Federica | Jokanović, Sandra | Jozić, Slaven | Kauzlarić, Vesna | Kraus, Romina | Marini, Mauro | Mikuš, Josip | Milandri, Stefania | Pećarević, Marijana | Perini, Laura | Quero, Grazia Marina | Šolić, Mladen | Lušić, Darija Vukić | Zoffoli, Silvia
Ports are subject to a variety of anthropogenic impacts, and there is mounting evidence of faecal contamination through several routes. Yet, little is known about pollution in ports by faecal indicator bacteria (FIB). FIB spatio-temporal dynamics were assessed in 12 ports of the Adriatic Sea, a semi-enclosed basin under strong anthropogenic pressure, and their relationships with environmental variables were explored to gain insight into pollution sources. FIB were abundant in ports, often more so than in adjacent areas; their abundance patterns were related to salinity, oxygen, and nutrient levels. In addition, a molecular method, quantitative (q)PCR, was used to quantify FIB. qPCR enabled faster FIB determination and water quality monitoring that culture-based methods. These data provide robust baseline evidence of faecal contamination in ports and can be used to improve the management of routine port activities (dredging and ballast water exchange), having potential to spread pathogens in the sea.
Показать больше [+] Меньше [-]Optimizing a coastal monitoring network using a water-quality response grid (WRG)-based sampling design for improved reliability and efficiency Полный текст
2019
Duan, Ke | Li, Keqiang | Liang, Shengkang | Li, Yanbin | Su, Ying | Wang, Xiulin
Marine monitoring in Bohai Sea is delivered within three networks by lacking appropriate sampling and assessment methodologies. Water-quality response grid (WRG)-based sampling design using optimization and multi-factors assessment can reliably detect a variety of environmental impacts. Which includes 5 steps: selects environmental reference factors, divides the sampling grid, sets the initial stations, optimizes the sampling stations, and assesses the proposed network's reproducibility and efficiency. We applied this method to the Bohai Sea, the networks proposed here have 225 stations for optimized special surveys (OSS) and 181 stations for optimized operational monitoring (OOM), accounting for 46.5% and 37.4% of the original station totals, respectively. Besides, the reproducibility and efficiency index (REI) of OSS and OOM stations approximately 15.4% and 13.3% higher than three current monitoring networks on average among multi-factors in 4 seasons. Thus, the method can improve the reproducibility, efficiency and land-sea spatial matching of monitoring network.
Показать больше [+] Меньше [-]Distribution and pollution assessment of heavy metals in the intertidal zone environments of typical sea areas in China Полный текст
2019
Zhao, Mengwei | Wang, Enkang | Xia, Peng | Feng, Aiping | Ji, Yuan | Sun, Yonggen
The heavy metals (Cu, Cr, Zn, Cd, Pb) were analysed for 217 surface sediment samples collected across 14 typical intertidal zone areas in China. The data reveals the heavy metals spatial distribution patterns and correlations among their concentrations. Cu, Zn, Cd and Cr showed similar trends of spatial variation and the correlations between the concentrations of every two heavy metals were significantly positive except for the correlation between Pb and Cr concentrations. By using Nemerow index method, Enrichment factor and Sediment Quality Guidelines, it is found that Hangzhou Bay and Jiulong River Estuary were polluted, Yingluo Bay and Dongzhaigang Bay were Cd-rich areas. Except Beidaihe shoal, Sishili Bay and Yingluo Bay that were not exposed to any ecological risk of heavy metals and had no adverse biotoxic effects, the other 11 typical intertidal zone areas were exposed to moderate ecological risk of heavy metals in the sediment with potential adverse biotoxic effects.
Показать больше [+] Меньше [-]Distribution and ecotoxicological effects of polyhalogenated carbazoles in sediments from Jiaozhou Bay wetland Полный текст
2019
Zhu, Huihui | Zheng, Minggang | Zheng, Li | Wang, Ling | Lou, Yinghua | Zhao, Quansheng | Zhang, Yu
A suite of eight polyhalogenated carbazole (PHCZ) congeners were detected in sediments of the Jiaozhou Bay wetland. 3,6-dichlorocarbazole (36-CCZ), and 3,6-dibromocarbazole (36-BCZ) were detected in all samples. The concentrations of ΣPHCZs ranged from 6.9 to 33.4 ng/g dry weight (dw). The recovery of surrogate standard ranged from 85 to 109%. Significant relationships were found between the concentrations of 36-CCZ and those of the other three detected compounds (36-BCZ, 36-ICZ, and 1368-BCZ). However, with regard to the other chemicals, only 1368-BCZ was related to 36-ICZ. The toxic equivalent (TEQ) was used to assess the relative toxicity of PHCZs, which ranged within 0.1–3.9 pg TEQ/g dw in sediment. The inventory of ΣPHCZs was 58.9 kg. These results indicate that PHCZs are widely distributed in the Jiaozhou wetland and the dyeing and finishing industries may be important contamination sources of PHCZs.
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