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Noise Pollution and Urban Planning 全文
2018
Morillas, Juan Miguel Barrigón | Gozalo, Guillermo Rey | González, David Montes | Moraga, Pedro Atanasio | Vílchez-Gómez, Rosendo
Noise pollution distribution in each city around the world is necessarily influenced by its own design. A lot of factor associated to urban planning have a considerable effect on volume of traffic, vehicles distribution, traffic conditions, etc. And it is know that, from a temporal and spatial point of view, the most important source of noise in cities is road traffic. For that, good relationships between urban planning and different factors such as urban density, urban morphology, urban land use, street distribution, street environment and green spaces are being founded. In this way, the fact of finding a sustainable city could be closer, at least with respect to noise pollution. A good knowledge of these relationships would allow better prediction, analysis and prevention of such pollution through an effective design of urban environments. However, although in the first decade of XXI century these relationships were treated in some works, only some aspects of these problems were considered, essentially focused on street functionality. In the last years, this topic has reached more important development and more studies focused on the analysis of the relationships between the distributions of pollution and urbanism. This work makes a revision of spatial sampling methodologies for noise pollution assessment in relation with urban planning and a review of studies that have analysed the relationships between urban noise and different specifics aspects of urban design.
显示更多 [+] 显示较少 [-]Mercury in dated sediment cores from coastal ponds of St Thomas, USVI 全文
2018
Benoit, Gaboury
We collected seven cores from five coastal ponds in St Thomas, USVI, dated them via 210Pb, and measured their Hg profiles. Levels ranged from 20 to 100ngg−1 and always increased upward to the surface or a shallow mixed zone. Taking into account differences in sediment accumulation rates and the presence or absence of a mixed zone, all sites revealed similar deposition histories. Mercury levels were at low, possibly pristine, values until the early to mid-20th century. Then they then doubled or quadrupled steadily until about 1990, after which Hg became relatively constant. We conclude that Hg in the sediments of these ponds came from long range deposition directly to the ponds and to their watersheds. Constant levels in recent years may be caused by transfer from watersheds, a pathway that is delayed compared to direct deposition from the atmosphere.
显示更多 [+] 显示较少 [-]Water quality near Estonian harbours in the Baltic Sea as observed from entire MERIS full resolution archive 全文
2018
Sipelgas, Liis | Uiboupin, Rivo | Arikas, Age | Siitam, Laura
Variations and trends in water quality parameters (total suspended matter and coloured dissolved organic matter) were examined in five harbours in the eastern Baltic Sea using satellite imagery collected from 2002 to 2011 by the Medium Resolution Imaging Spectrometer (MERIS) at full spatial resolution (300×300m). In the eastern Gulf of Finland harbours (Sillamäe, Kunda) the TSM monthly variations were related to monthly mean wind speed. In Tallinn harbour, which operates >6000 vessels annually, evidence of anthropogenic impacts was identified through inter-annual TSM variations. The vessel traffic footprint was ascertained from the significant correlation (R=0.66; p=0.035) between the number of annual vessel visits and mean annual TSM concentration. In the harbour of Pärnu, located close to the river mouth, inter-annual water quality variations in terms of the CDOM concentrations were affected by the mean annual river discharge levels of the Pärnu River.
显示更多 [+] 显示较少 [-]Plastic cigar tips debris: Exploring use and disposal issues for Lake Erie beaches 全文
2018
Hardy, Scott D. | Bartolotta, Jill
Great Lakes states are increasingly faced with questions regarding how plastic debris is impacting marine and coastal ecosystems. This is especially evident along the southern beaches of Lake Erie, where high population and industrial development have contributed to the plastics problem. In Ohio, the most common items found are cigarettes and other smoking related materials, including plastic cigar tips. Given the growing awareness of the issue, and the impact of plastics on beaches throughout the Great Lakes, a focus group convened to investigate strategies to help address the problem. The group was comprised of individuals with practical knowledge of plastic cigar tip use and disposal issues, including representatives of government agencies, nongovernmental organizations, community groups, and local academic institutions. This report represents the exploratory results of the focus group, complete with information regarding the what, why, and how of plastic cigar tip debris in the region, guidance on the material and social barriers to sustaining desired behaviors (cessation of use by minors and/or proper disposal), strategies to overcome those barriers, and suggestions for management and policy actions moving forward. Group members suggest that a combination of education and government-supported financial incentives may be the most effective approach, with community-based positive messaging backed by local taxes on smoking items that have plastic tips and rebates or other rewards for properly disposing of debris.
显示更多 [+] 显示较少 [-]Application of Box-Behnken design in response surface methodology for the molecularly imprinted polymer pipette-tip solid phase extraction of methyl red from seawater samples and its determination by spectrophotometery 全文
2018
Hashemi, Sayyed Hossein | Kaykhaii, Massoud | Keikha, Ahmad Jamali | Sajjadi, Zahra
In this paper, a rapid, selective and effective technique, pipette-tip solid phase extraction based on molecularly imprinted polymer, was used for extraction and pre-concentration of methyl red (MR) prior to its determination by spectrophotometer. Variables influencing extraction efficiency including type and volume of eluent solvent, sample volume, number of cycles of extraction and elution, amount of sorbent and pH of the sample solution were optimized with two methods of one-variable-at-a-time and response surface methodology (RSM). For RSM optimization, seven factors in three-levels were utilized for Box-Behnken experimental design. Under optimum conditions, a linear calibration graph in the range of 3.0–300.0 μg L−1 for MR was resulted. The limit of detection of proposed method was 0.50 μg L−1 for MR. Finally, the investigated method was used for the determination of MR in seawater and the mean recoveries were calculated to be 84.0–98.0% with mean RSD of 2.5–6.7%.
显示更多 [+] 显示较少 [-]Distribution characteristics, sources and ecological risk of antimony in the surface sediments of Changjiang Estuary and the adjacent sea, East China 全文
2018
Zhuang, Wen | Lai, Xiaoying | Wang, Qian | Liu, Yongxia | Chen, Qing | Liu, Chang
The distribution characteristics, sources and ecological risk of antimony (Sb) in the surface sediments of Changjiang Estuary and the adjacent sea were studied. Sb concentrations ranged from 0.320 to 0.968 μg g−1 with mean value of 0.577 μg g−1. Sb concentrations were relatively high in sediments of the south Yellow Sea, the Hangzhou Bay mouth and the inner Changjiang Estuary. The variation trend of Sb concentrations was controlled by hydrodynamics, Al/Fe/Mn oxides. Sb also showed strong chalcophile property. Correlation analysis and enrichment factor showed Sb came mainly from natural sources. Total Sb sediment flux in the study area was 446.3 t/yr. The Changjiang River, the Yellow River and atmospheric inputs accounted for 85.7%, 13.9%, and 0.4% of the total sediment Sb flux, respectively. The result of potential ecological index indicated the very low Sb concentrations could hardly threat the ecological environment of the study area.
显示更多 [+] 显示较少 [-]Surface sediment properties and heavy metal contamination assessment in river sediments of the Pearl River Delta, China 全文
2018
Zhao, Guangming | Ye, Siyuan | Yuan, Hongming | Ding, Xigui | Wang, Jin | Laws, Edward A.
Concentrations of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), lead (Pb), and zinc (Zn), grain sizes, and concentrations of organic carbon (Corg) were measured in 323 river sediment samples from the Pearl River Delta (PRD). Results showed that the heavy metal concentrations in the sediments ranged from 1.6–93 mg/kg for As, 0.04–9.3 mg/kg for Cd, 2–315 mg/kg for Cr, 1.1–352 mg/kg for Cu, 0.01–0.67 mg/kg for Hg, 11–221 mg/kg for Pb, and 11–1234 mg/kg for Zn. The highest values of As, Cr, Cu, Hg, Pb, and Zn appeared in the Beijiang River, whereas Cd was high in the Xijiang River. The overall sediment quality in the area with respect to metal concentrations generally met the primary standard criteria of China (Marine Sediment Quality), except for Cd and Cu. The spatial distributions of the heavy metals were influenced by both grain sizes and Corg concentrations. The Igeo geo-accumulation index indicated that there was no significant Cr, Cu, Hg, or Zn pollution, slight to moderate pollution by As and Pb, and moderate Cd pollution in the study area. Spatial distributions of an eco-toxicological index based on probable effect levels indicated that there was a 21% probability that the combination of the seven metals was exerting a toxic stress in the PRD river sediments.
显示更多 [+] 显示较少 [-]Tissue-specific metabolic responses of the pearl oyster Pinctada martensii exposed to benzo[a]pyrene 全文
2018
Chen, Hao | Diao, Xiaoping | Zhou, Hailong
Benzo[a]pyrene (BaP) is a polycyclic aromatic hydrocarbon (PAH) that is well known for its teratogenic, mutagenic and carcinogenic effects. In this study, we applied metabolomics to investigate the tissue-specific metabolic responses of the Pinctada martensii digestive glands and gills after a short-duration exposure to BaP (1 μg/L and 10 μg/L). After 72 h of exposure to BaP, the majority of metabolite changes were related to osmolytes, energy metabolites, and amino acids. BaP (1 μg/L) accelerated energy deterioration and decreased osmotic regulation, while BaP (10 μg/L) disturbed energy metabolism and increased osmotic stress in the digestive glands. Both BaP doses disturbed osmotic regulation and energy metabolism in the gills. BaP also induced neurotoxicity in both tissues. These findings demonstrated that BaP exhibited tissue-specific metabolic responses in P. martensii. The difference in these metabolite responses between the digestive glands and gills might prove to be suitable biomarkers for indicating exposure to specific marine pollutants.
显示更多 [+] 显示较少 [-]Metal concentrations in seagrass (Halophila ovalis) tissue and ambient sediment in a highly modified estuarine environment (Sydney estuary, Australia) 全文
2018
Birch, G.F. | Cox, B.M. | Besley, C.H.
Research into sediment-seagrass tissue metal relationships has been undertaken in Sydney estuary due to the recognized role contamination plays in threats to seagrass health. Seagrass (Halophila ovalis) leaf tissue concentrations are elevated in Cu, Pb and Zn and contain the highest reported root Cr concentrations. Seagrass metal concentrations were significantly different between species H. ovalis and Zostera capricorni; between root and leaf tissue; and between sampling locations. Greatest tissue enrichment was for Pb, however metals were not enriched in seagrass relative to surficial sediment. Fine and total sediment metal concentrations were temporally consistent between collection years 2013/15, whereas root tissue metals changed between years and sites and leaf metal contents were temporally inconsistent. Extractable metal concentrations in fine sediment (<62.5 μm) showed moderate significant correlation with root tissue and a weak significant relationship with leaf tissue, whereas total sediment metal showed no such relationships. Management implications are provided.
显示更多 [+] 显示较少 [-]Phycotoxins in scallops (Patinopecten yessoensis) in relation to source, composition and temporal variation of phytoplankton and cysts in North Yellow Sea, China 全文
2018
Wu, Hai-Yan | Luan, Qing-Shan | Guo, Meng-Meng | Gu, Hai-Feng | Zhai, Yu-Xiu | Tan, Zhi-Jun
The North Yellow Sea is a major aquaculture production area for the scallop Patinopecten yessoensis. In this study, the temporal and spatial variation of phycotoxins in scallops, phytoplankton, and their cysts were analyzed during a survey conducted from June 2011 to April 2012 around Zhangzi Island. The study area is a semi-enclosed epicontinental sea surrounded by the Shandong Peninsula, the Liaodong Peninsula and the Korean Peninsula. The three main results of the study were as follows: (1) The saxitoxin-group toxins, okadaic acid and analogues, and pectenotoxins were the major phycotoxin residues found in scallops; (2) Six kinds of toxic microalgae were identified, Protoperidinium spp., Gonyaulax spp., and Alexandrium spp. were the dominant taxa; Seven types of potential marine toxin-producing dinoflagellates, A. tamarense, A. catenella, Dinophysis fortii, G. catenatum, Gambierdiscus toxicus, Azadinium poporum, and Pseudo-nitzschia pungen were identified as the primary source of phycotoxins and were present at relatively high density from June to October; and (3) azaspiracids and domoic acid might be new potential sources of toxin pollution. This study represents the first assessment to phycotoxins around Zhangzi Island in the North Yellow Sea.
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