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First evidence of presence of plastic debris in stomach of large pelagic fish in the Mediterranean Sea 全文
2015
Romeo, Teresa | Pietro, Battaglia | Pedà, Cristina | Consoli, Pierpaolo | Andaloro, Franco | Fossi, Maria Cristina
This study focuses, for the first time, on the presence of plastic debris in the stomach contents of large pelagic fish (Xiphias gladius, Thunnus thynnus and Thunnus alalunga) caught in the Mediterranean Sea between 2012 and 2013. Results highlighted the ingestion of plastics in the 18.2% of samples. The plastics ingested were microplastics (<5mm), mesoplastics (5–25mm) and macroplastics (>25mm).These preliminary results represent an important initial phase in exploring two main ecotoxicological aspects: (a) the assessment of the presence and impact of plastic debris on these large pelagic fish, and (b) the potential effects related to the transfer of contaminants on human health.
显示更多 [+] 显示较少 [-]Inactivation of microalgae in ballast water with pulse intense light treatment 全文
2015
Feng, Daolun | Shi, Jidong | Sun, Dan
The exotic emission of ballast water has threatened the coastal ecological environment and people’s health in many countries. This paper firstly introduces pulse intense light to treat ballast water. 99.9±0.09% inactivation of Heterosigma akashiwo and 99.9±0.16% inactivation of Pyramimonas sp. are observed under treatment conditions of 350V pulse peak voltage, 15Hz pulse frequency, 5ms pulse width and 1.78L/min flow rate. The energy consumption of the self-designed pulse intense light treatment system is about 2.90–5.14 times higher than that of the typical commercial UV ballast water treatment system. The results indicate that pulse intense light is an effective technique for ballast water treatment, while it is only a competitive one when drastic decreasing in energy consumption is accomplished.
显示更多 [+] 显示较少 [-]A comparison of microscopic and spectroscopic identification methods for analysis of microplastics in environmental samples 全文
2015
Song, Young Kyoung | Hong, Sang Hee | Jang, Mi | Han, Gi Myung | Rani, Manviri | Lee, Jongmyoung | Shim, Won Joon
The analysis of microplastics in various environmental samples requires the identification of microplastics from natural materials. The identification technique lacks a standardized protocol. Herein, stereomicroscope and Fourier transform infrared spectroscope (FT-IR) identification methods for microplastics (<1mm) were compared using the same samples from the sea surface microlayer (SML) and beach sand. Fragmented microplastics were significantly (p<0.05) underestimated and fiber was significantly overestimated using the stereomicroscope both in the SML and beach samples. The total abundance by FT-IR was higher than by microscope both in the SML and beach samples, but they were not significantly (p>0.05) different. Depending on the number of samples and the microplastic size range of interest, the appropriate identification method should be determined; selecting a suitable identification method for microplastics is crucial for evaluating microplastic pollution.
显示更多 [+] 显示较少 [-]Bioaccumulation and ecological risk assessment of heavy metals in the sediments and mullet Liza klunzingeri in the northern part of the Persian Gulf 全文
2015
Bastami, Kazem Darvish | Afkhami, Majid | Mohammadizadeh, Maria | Ehsanpour, Maryam | Chambari, Shahrokh | Aghaei, Sina | Esmaeilzadeh, Marjan | Neyestani, Mahmoud Reza | Lagzaee, Farahnaz | Baniamam, Mehrnaz
The concentrations of some heavy metals (Cu, Zn, Pb and Cd) were investigated in the sediments and in the mullet Liza klunzingeri from the northern part of the Persian Gulf. The levels of Cu, Zn and Pb in the sediment varied significantly among the sampling sites (P<0.05). Sediments from the northern part of the Persian Gulf had serious ecological risk when considering PER. The ranges of the average concentrations of Cu, Zn, Pb, and Cd in the tissue of L. klunzingeri were 10.00–16.66mg/kg, 18.75–32.50mg/kg, 3.25–14.16mg/kg and 0.37–3.33mg/kg, respectively. The health risk analysis of individual heavy metals in the fish tissue indicated dangerous levels of Pb and Cd for the general population at some sampling sites.
显示更多 [+] 显示较少 [-]Assessing shelf aggregate environmental compatibility and suitability for beach nourishment: A case study for Tuscany (Italy) 全文
2015
Bigongiari, Nicola | Cipriani, Luigi E. | Pranzini, Enzo | Renzi, Monia | Vitale, Giovanni
Beach nourishment practices are a key aspect in coastal management plans for stakeholders and communities. Stemming from a concrete case-study (Tuscany), this research analyzes: (i) principal problems of current law regulating dredging, (ii) gaps in technical guidelines, (iii) advantages of integrated approaches to the decision-making process, (iv) possible applicable nourishment options and their costs and benefits. Our results show that sand compatibility is driven mainly by grain-size stability due to the occurrence of lower pollution levels in off-shore deposits than in threatened beaches, thus current laws and guidelines should be improved to fill the evident gap in the evaluation process and to include a more complete approach to data evaluation and an integrated approach to ecotoxicity evaluation, which is relevant in cases of geochemical anomalies. The cost-benefit analysis performed indicates that only dredging intended to manage more than 1millionm3 of aggregates would represent a real advantage for local communities.
显示更多 [+] 显示较少 [-]Contamination of the southern Baltic Sea waters by the residues of selected pharmaceuticals: Method development and field studies 全文
2015
Borecka, Marta | Siedlewicz, Grzegorz | Haliński, Łukasz P. | Sikora, Kinga | Pazdro, Ksenia | Stepnowski, Piotr | Białk-Bielińska, Anna
In this study the occurrence of thirteen pharmaceuticals in seawaters collected from southern Baltic Sea was evaluated for the first time. It was performed by applying newly developed analytical procedure. The method was characterized in terms of its basic validation parameters as well as matrix effects, extraction efficiency and absolute recovery. The results were expressed as result±expanded uncertainty, which was estimated according to the Guide to the Expression of Uncertainty in Measurement. Additionally, in order to verify the influence of variable parameters of the analyzed samples on method performance parameters, chemometric analysis was carried out. The obtained results revealed that residues of pharmaceuticals were present in seawaters at a concentration level of ngL−1. Trimethoprim, sulfamethoxazole and enrofloxacin were most frequently detected compounds. The highest concentration was determined for ketoprofen (135.0±10.9ngL−1). Marine pollution potential hotspots were found in enclosed or semi-enclosed bodies of water.
显示更多 [+] 显示较少 [-]Modeling increased riverine nitrogen export: Source tracking and integrated watershed-coast management 全文
2015
Yu, Dan | Yan, Weijin | Chen, Nengwang | Peng, Benrong | Hong, Huasheng | Zhuo, Guihua
The global NEWS model was calibrated and then used to quantify the long term trend of dissolved inorganic nitrogen (DIN) export from two tributaries of Jiulong River (SE China). Anthropogenic N inputs contributed 61–92% of river DIN yield which increased from 337 in 1980s to 1662kgNkm−2yr−1 in 2000s for the North River, and from 653 to 3097kgNkm−2yr−1 for the West River. North River and West River contributed 55% and 45% respectively of DIN loading to the estuary. Rapid development and poor management driven by national policies were responsible for increasing riverine N export. Scenario analysis and source tracking suggest that reductions of anthropogenic N inputs of at least 30% in the North River (emphasis on fertilizer and manure) and 50% in the West River (emphasis on fertilizer) could significantly improve water quality and mitigate eutrophication in both river and coastal waters.
显示更多 [+] 显示较少 [-]Baseline distribution and sources of linear alkyl benzenes (LABs) in surface sediments from Brunei Bay, Brunei 全文
2015
Alkhadher, Sadeq Abullah Abdo | Zakaria, Mohamad Pauzi | Fatimah Md. Yusoff, | Kannan, Narayanan | Suratman, Suhaimi | Keshavarzifard, Mehrzad | Magam, Sami Muhsen | Masood, Najat | Vaezzadeh, Vahab | Sani, Muhamad Shirwan Abdullah
Sewage pollution is one of major concerns of coastal and shoreline settlements in Southeast Asia, especially Brunei. The distribution and sources of LABs as sewage molecular markers were evaluated in surface sediments collected from Brunei Bay. The samples were extracted, fractionated and analyzed using gas chromatography- mass spectrometry (GC-MS). LABs concentrations ranged from 7.1 to 41.3ngg−1 dry weight (dw) in surficial sediments from Brunei Bay. The study results showed LABs concentrations variably due to the LABs intensity and anthropogenic influence along Brunei Bay in recent years. The ratio of Internal to External isomers (I/E ratio) of LABs in sediment samples from Brunei Bay ranged from 0.56 to 2.17 along Brunei Bay stations, indicating that the study areas were receiving primary and secondary effluents. This is the first study carried out to assess the distribution and sources of LABs in surface sediments from Brunei Bay, Brunei.
显示更多 [+] 显示较少 [-]Historic and contemporary contamination in the marine environment of Kuwait: An overview 全文
2015
Al-Sarawi, Hanan A. | Jha, Awadhesh N. | Al-Sarawi, Mohammad A. | Lyons, Brett P.
The rapid expansion of industry, along with previous pollution events linked to conflicts in the region, have led to a variety of contaminants being inadvertently or deliberately discharged into Kuwait’s marine environment. These include polycyclic aromatic hydrocarbons (PAHs) and trace metals, from the petrochemical industry, and contaminated brine from the region’s desalination industries. The present paper has reviewed over 60 studies that have reported the levels of contaminants, including PAHs, metals and polychlorinated biphenyls (PCBs) present in seawater, sediment and representative marine organisms. Most of the reviewed literature confirmed that while Kuwait’s marine environment has been subjected to a wide array of pollution events, the actual levels of contamination remains relatively low. However, sediment contamination hotspots associated with point sources of industrial contamination, such as originating from the Shuaiba industrial area, do exist at a number of locations around the coast.
显示更多 [+] 显示较少 [-]Ecophysiological responses of three Mediterranean invasive seaweeds (Acrothamnion preissii, Lophocladia lallemandii and Caulerpa cylindracea) to experimental warming 全文
2015
Samperio-Ramos, Guillermo | Olsen, Ylva S. | Tomas, Fiona | Marbà, Núria
The Mediterranean Sea is a hotspot for invasive species and projected Mediterranean warming might affect their future spreading. We experimentally examined ecophysiological responses to the temperature range 23–31°C in three invasive seaweeds commonly found in the Mediterranean: Acrothamnion preissii, Caulerpa cylindracea and Lophocladia lallemandii. The warming range tested encompassed current and projected (for the end of 21st Century) maximum temperatures for the Mediterranean Sea. Optimal ecophysiological temperatures for A. preissii, C. cylindracea and L. lallemandii were 25°C, 27°C and 29°C, respectively. Warming below the optimal temperatures enhanced RGR of all studied invasive seaweeds. Although sensitive, seaweed photosynthetic yield was less temperature-dependent than growth. Our results demonstrate that temperature is a key environmental parameter in regulating the ecophysiological performance of these invasive seaweeds and that Mediterranean warming conditions may affect their invasion trajectory.
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