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Black coral as a new environmental recorder: The lead profiles in coral skeletons over the past century 全文
2015
Lu, Shan | Cai, Weiying | Zhang, Xiaodi | Li, Xiubao | Huang, Hui | Zhang, Fenfen | Zhang, Jing
Lead (Pb) is a typical heavy metal pollutant in the environment, and most Pb contamination comes from human activities. In the present work, the Pb contents of two black coral specimens (Cirrhipathes spp.) collected from the northern South China Sea were measured by synchrotron radiation micro X-ray fluorescence (SR μ-XRF) analysis with 2.5μm resolution. The results showed that sample SY-1 from the Sanya Bay (near the continent) exhibited higher Pb levels and greater fluctuations than sample XS-1 from the Xisha Islands (off the continent), reflecting the influence of terrestrial input and atmospheric deposition in coastal surface seawater. The present work also demonstrated that the Pb profile in black coral nearshore was highly influenced by human activities, mainly by war and economic development. Thus, black coral may serve as a new potential environmental Pb recorder with SR μ-XRF analytical technology.
显示更多 [+] 显示较少 [-]Indoor air quality in urban nursery schools in Gliwice, Poland: Analysis of the case study 全文
2015
Mainka, Anna | Brągoszewska, Ewa | Kozielska, Barbara | Pastuszka, Józef S. | Zajusz-Zubek, Elwira
Children's exposure to air pollutants is an important public health challenge. Particular attention should be paid to preschools because younger children are more vulnerable to air pollution than higher grade children and spend more time indoors. The purpose of this study was to compare the indoor air quality (IAQ) at nursery schools located in Gliwice, Poland.We investigated the concentrations of volatile organic compounds (VOCs), particulate matter (PM) and bacterial and fungal bioaerosols, as well as carbon dioxide (CO2) concentrations in younger and older children's classrooms during the winter season at two urban nursery schools, located within traffic and residential areas. The concentration of the investigated pollutants in indoor environments was higher than those in outdoor air. The results clearly indicate the problem of elevated concentrations of PM2.5 and PM10 inside the classrooms. High levels of CO2 exceeding 1000 ppm in relation to outdoor air also confirmed the low indoor air quality of classrooms. This is concerning in terms of the exposure effects on the health of children. The relation between IAQ in older and younger children's classrooms was also statistically significant in the case of PM and CO2.Improving ventilation, decreasing the occupancy per room and completing cleaning activities following occupancy periods can contribute to alleviating high CO2 and particle levels.
显示更多 [+] 显示较少 [-]Latitudinal variation and residence time of 137Cs in Indian coastal environment 全文
2015
Sartandel, S.J. | Jha, S.K. | Tripathi, R.M.
Anthropogenic 137Cs activity concentration, in surface sea water along the western and eastern coast of India has been estimated using the in-situ pre-concentration approach. Activity levels of 137Cs ranges from 0.09–1.30Bqm−3 with an overall mean of 0.69±0.29Bqm−3. Latitudinal variation and higher depletion in activity concentration of 137Cs at few locations were observed. Temporal change of 137Cs in sea water along Indian coast unveils a lower effective half-life of 13.8±0.7y in comparison to Asia Pacific regional sea water. The results prevailed that the spatial distribution confers no fresh input of 137Cs in Indian coastal region.
显示更多 [+] 显示较少 [-]Relative bioavailability and toxicity of fuel oils leaking from World War II shipwrecks 全文
2015
Faksness, Liv-Guri | Daling, Per | Altin, Dag | Dolva, Hilde | Fosbæk, Bjørn | Bergstrøm, Rune
The Norwegian Authorities have classified 30 WWII shipwrecks to have a considerable potential for pollution to the environment, based on the location and condition of the wreck and the types and amount of fuel. Oil thus far has been removed from eight of these shipwrecks. The water accommodated fractions of oils from two British wrecks and two German wrecks have been studied with special emphasis on chemistry and biological effects (algae growth (Skeletonema costatum) and copepod mortality (Calanus finmarchicus)). Chemical analyses were also performed on three additional German wreck oils. The results from these studies show that the coal based oils from German WWII shipwrecks have higher toxicity to marine organisms than the mineral oils from the British shipwrecks. The potential for higher impact on the marine environment of coal based oils has resulted in an altering of the priority list for oil recovery from WWII wrecks by the authorities.
显示更多 [+] 显示较少 [-]Spatial distribution of some trace and major elements in sediments of the Cávado estuary (Esposende, Portugal) 全文
2015
Gredilla, Ainara | Stoĭchev, Teodor | Fdez-Ortiz de Vallejuelo, Silvia | Rodriguez-Iruretagoiena, Azibar | de Morais, Paulo | Arana, Gorka | de Diego, Alberto | Madariaga, Juan Manuel
For the first time, the occurrence and spatial distribution of several elements, including some toxic metals, have been investigated in sediments of the estuary of the Cávado River (Esposende, Portugal). The pseudo total concentrations of Al, As, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sn, V and Zn in sediments collected at 24 sites covering the tidal part of the estuary were determined. According to the concentrations measured, the Cávado estuary can be considered as non-contaminated. For most of the elements, the concentrations tended to be higher upstream. Only a moderate enrichment in Cr and Ni was detected in a few sites. An important decrease in concentration was observed for the most toxic metals compared to historical data reported in the literature. Several hotspots were identified, but even in those cases the amount of metals stored in the sediments does not represent a toxicological threat to living organisms.
显示更多 [+] 显示较少 [-]Distributions and sources of petroleum, aliphatic hydrocarbons and polycyclic aromatic hydrocarbons (PAHs) in surface sediments from Bohai Bay and its adjacent river, China 全文
2015
Wang, Min | Wang, Chuanyuan | Hu, Xiaoke | Zhang, Haijiang | He, Shijie | Lv, Shuangyan
Surface sediment samples from Bohai Bay and its adjacent river, China, were analyzed for aliphatic hydrocarbon, PAHs and biomarkers in order to determine the distribution, composition and source of organic matter in a coastal environment. Results suggested that the input of organic matter from anthropogenic activities has a more significant influence on its distribution than that from natural processes. Petroleum contamination, mainly from offshore oil exploration and discharge of pollutants from rivers, was the main source of n-alkanes. PAHs were mostly of pyrogenic origin; while some sites in Yellow River Estuary were derived mainly from the petrogenic sources. The toxic assessment suggested that the PAHs in surface sediments will not cause immediately adverse biological effects in sediments from Bohai Bay and its adjacent river, China.
显示更多 [+] 显示较少 [-]Characterization of estrogenic receptor agonists and evaluation of estrogenic activity in the sediments of Liaohe River protected areas 全文
2015
Ke, Xin | Wang, Chunyong | Zhang, Haijun | Zhang, Yun | Gui, Shaofeng
Estrogenic activity of 12 sediment samples from Liaohe River protected areas was evaluated by the recombinant yeast bioassays. The bioassay-derived 17β-estradiol equivalents of crude extracts (Bio-EEQcrudes) were between 52.2 and 207.6pg/g dry weight. The most concerned estrogenic receptor (ER) agonists including estrone (E1), 17β-estradiol (E2), estriol (E3), 17α-ethynylestradiol (EE2), 4-nonylphenols (4-NP), bisphenol A (BPA), and organochlorine pesticides (OCPs) were determined. The concentrations of E1, E2, E3, EE2, BPA, andΣ10OCPs ranged up to 203.3pg/g, 185.8pg/g, 237.7pg/g, 188.5pg/g, 51.0ng/g, and 3.6ng/g, respectively. Taken together with polarity-based fractionation, in vitro bioassay and chemical analysis, it indicated that E1, E2, and EE2 were the predominant ER agonists and were mainly from the discharge of domestic wastewater and breeding wastewater. Meanwhile, this study showed that the establishment of protected areas had not obviously reduced the ecological risk caused by ER agonists in Liaohe River protected areas sediments.
显示更多 [+] 显示较少 [-]Mapping elements distribution in carapace of Caretta caretta: A strategy for biomonitoring contamination in sea turtles? 全文
2015
Mattei, D. | Veschetti, E. | D’Ilio, S. | Blasi, M.F.
This study analyzed the carapace distribution of Ca, Cd, Cr, Cu, Mg, Mn, Pb, Sb, U, V and Zn by GF-AAS and ICP-AES in one specimen of Caretta caretta from Mediterranean Sea. Calcium, Mg, Mn, Pb, U, Zn were mainly distributed in the central area while Cd, Cr, Cu, Sb, V in lateral areas. Cadmium, Cr, Mg, Mn, Sb, U and V were different between lateral areas.The different distribution may be related to several exposures during lifetime and/or the shell ossification during growth. Carapace may be a suitable matrix for metal biomonitoring, however, further studies are required to confirm these findings.
显示更多 [+] 显示较少 [-]Prospects for cost-efficient water protection in the Baltic Sea 全文
2015
Hyytiäinen, Kari | Ahlvik, Lassi
Prospects for cost-efficient water protection in the Baltic Sea 全文
2015
Hyytiäinen, Kari | Ahlvik, Lassi
This study investigates the economic consequences of the nutrient load reductions agreed in the 2013 revision of the Baltic Sea Action Plan. The cost of meeting the targets set for waterborne sources was estimated to be 1980 MEUR annually. The 2013 revision is a step towards cost-efficient water protection: the cost of meeting the earlier targets would have been 328 MEUR (14%) higher, although the revised targets are now more ambitious with respect to phosphorus. We demonstrate that there is potential for efficiency gains by introducing flexibility mechanisms, such as ‘joint implementation’ to trans-boundary water protection. The potential gains can be as high as 280 MEUR (14%). The most flexible interpretation of the basin targets, one allowing Contracting Parties to account for reductions in other sea basins in proportion to their effect in the focal basin, could further reduce the total cost by 200 MEUR (12%).
显示更多 [+] 显示较少 [-]Prospects for cost-efficient water protection in the Baltic Sea 全文
2015
Hyytiäinen, Kari | Ahlvik, Lassi | Luke / Talous ja yhteiskunta / Luonnonvarojen hyödyntäminen / Ympäristötalous (400403) | 400403
This study investigates the economic consequences of the nutrient load reductions agreed in the 2013 revision of the Baltic Sea Action Plan. The cost of meeting the targets set for waterborne sources was estimated to be 1980 MEUR annually. The 2013 revision is a step towards cost-efficient water protection: the cost of meeting the earlier targets would have been 328 MEUR (14%) higher, although the revised targets are now more ambitious with respect to phosphorus. We demonstrate that there is potential for efficiency gains by introducing flexibility mechanisms, such as ‘joint implementation’ to trans-boundary water protection. The potential gains can be as high as 280 MEUR (14%). The most flexible interpretation of the basin targets, one allowing Contracting Parties to account for reductions in other sea basins in proportion to their effect in the focal basin, could further reduce the total cost by 200 MEUR (12%). | 2015
显示更多 [+] 显示较少 [-]Effects of subchronic exposure to glyphosate in juvenile oysters (Crassostrea gigas): From molecular to individual levels 全文
2015
Mottier, Antoine | Séguin, Alexis | Devos, Alexandre | Pabic, Charles Le | Voiseux, Claire | Lebel, Jean Marc | Serpentini, Antoine | Fievet, Bruno | Costil, Katherine
Glyphosate-based herbicides are extensively used and can be measured in aquatic ecosystems, including coastal waters. The effect of glyphosate on non-target organisms is an issue of worldwide concern. The aim of this study was to investigate the effects of subchronic exposure to glyphosate in juvenile oysters, Crassostrea gigas. Yearling oysters were exposed to three concentrations of glyphosate (0.1, 1 and 100μgL−1) for 56days. Various endpoints were studied, from the individual level (e.g., gametogenesis and tissue alterations) to the molecular level (mRNA quantification), including biochemical endpoints such as glutathione-S-transferase (GST) and catalase activities and malondialdehyde content. No mortality and growth occurred during the experiment, and individual biomarkers revealed only slight effects. The levels of gene expression significantly increased in oysters exposed to the highest glyphosate concentration (GST and metallothioneins) or to all concentrations (multi-xenobiotic resistance). These results suggested an activation of defence mechanisms at the molecular level.
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