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Noise Pollution and Urban Planning Полный текст
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.
Показать больше [+] Меньше [-]Seagrass ecosystem services – What's next? Полный текст
2018
Nordlund, Lina Mtwana | Jackson, Emma L. | Nakaoka, Masahiro | Samper-Villarreal, Jimena | Beca-Carretero, Pedro | Creed, Joel. C.
Seagrasses, marine flowering plants, provide a wide range of ecosystem services, defined here as natural processes and components that directly or indirectly benefit human needs. Recent research has shown that there are still many gaps in our comprehension of seagrass ecosystem service provision. Furthermore, there seems to be little public knowledge of seagrasses in general and the benefits they provide. This begs the questions: how do we move forward with the information we have? What other information do we need and what actions do we need to take in order to improve the situation and appreciation for seagrass? Based on the outcomes from an international expert knowledge eliciting workshop, three key areas to advance seagrass ecosystem service research were identified: 1) Variability of ecosystem services within seagrass meadows and among different meadows; 2) Seagrass ecosystem services in relation to, and their connection with, other coastal habitats; and 3) Improvement in the communication of seagrass ecosystem services to the public. Here we present ways forward to advance seagrass ecosystem service research in order to raise the profile of seagrass globally, as a means to establish more effective conservation and restoration of these important coastal habitats around the world.
Показать больше [+] Меньше [-]Root activities and arsenic translocation of Avicennia marina (Forsk.) Vierh seedlings influenced by sulfur and iron amendments Полный текст
2018
Lin, Yushan | Fan, Jin | Yu, Jinfeng | Jiang, Shan | Yan, Chongling | Liu, Jingchun
Sulfur and iron are abundant and have close, complex interactions with the biogeochemical cycle of arsenic (As) in mangrove ecosystems. A hydroponic experiment was conducted to investigate the influences of variable SO42− and Fe2+ supplies on radial oxygen loss (ROL), iron plaque formation and As translocation in Avicennia marina upon exposure to As(III). The results indicate that A. marina is an As-tolerant plant, the application of iron and sulfur not only showed positive growth effects but also induced much higher amounts of ROL-induced iron plaque formation on root surfaces. The presence of iron plaque remarkably improved the proportion of As sequestration near this area but consequently reduced the proportion of As translocation in root. Therefore, it is concluded that iron plaque may act as a barrier for protection against As, and iron and sulfur play important roles in controlling the growth and translocation of As in A. marina seedlings.
Показать больше [+] Меньше [-]Evaluation of polycyclic aromatic hydrocarbons bioavailability on Santos Bay (Brazil) through levels of biliary metabolites Полный текст
2018
de Albergaria-Barbosa, Ana Cecília Rizzatti | da Silva, Denis Albuquerque Moreira | da Silva Rocha, Arthur José | Taniguchi, Satie | Patire, Vinicius Faria | Dias, June Ferraz | Fernandez, Wellington Silva | Bícego, Marcia Caruso
This study evaluated the PAH bioavailability from Santos Bay (Brazil) in 4 species of fish, using PAH biliary metabolites. The collection was done monthly, between July and December, in three different regions of Santos Bay. The metabolites were analyzed through a high performance liquid chromatograph with fluorescence detectors. Total metabolites concentrations ranged from 65.5 to 589μgg−1 of bile, evidencing PAH bioavailability on Santos Bay. Levels of phenanthrene and benzo[a]pyrene metabolites were in the classification range of areas moderate contaminated. Those concentrations were lower in Nebris microps and higher in Sphoeroides testudineus (p<0.05). Naphthalene metabolites concentrations did not differ significantly among fish species and were in the classification range of low contaminated areas. There were no significant spatial and temporal differences in levels among sampled areas. These results are environmentally important given the high levels of urbanization and the absence of biomonitoring data in this area.
Показать больше [+] Меньше [-]Accumulation of quaternary ammonium compounds as emerging contaminants in sediments collected from the Pearl River Estuary, China and Tokyo Bay, Japan Полный текст
2018
Dai, Xi | Wang, Cuicui | Lam, James C.W. | Yamashita, Nobuyoshi | Yamazaki, Eriko | Horii, Yuichi | Chen, Weifang | Li, Xiaolin
In this work, the distribution of quaternary ammonium compounds (QACs) in two dated sediment cores, collected from the Pearl River Estuary (PRE) and Tokyo Bay (TB), were investigated to understand the historical input of QACs and their diagenetic behavior in urban estuarine environments. The vertical variation profiles of QAC concentrations showed that benzylalkyldimethyl ammonium compounds (BACs) and dialkyldimethyl ammonium compounds (DADMACs) were widely used during 1970s and 1980s both in China and Japan. The declining environmental concentrations of QACs suggested a compositional change of commodities and the effectiveness of emission control strategies. For the individual QAC homologues, BAC homologues decreased significantly over time, while DADMAC compositions remained relatively stable. The differences in concentration and composition profiles of BACs and DADMACs in the sediment cores provided useful information on the patterns of use of QACs in China and Japan, as well as their diagenetic behaviors in the sediments.
Показать больше [+] Меньше [-]Levels of pollution of rare earth elements in the surface sediments from the Gulf of Pozzuoli (Campania, Italy) Полный текст
2018
Trifuoggi, Marco | Donadio, Carlo | Ferrara, Luciano | Stanislao, Corrado | Toscanesi, Maria | Arienzo, Michele
The Gulf of Pozzuoli includes the former second largest Italian steelworks of Bagnoli. The REE, Y, Th and Sc pollution in sediments of the Gulf of Pozzuoli was determined. Ce, La, Nd and Pr had the highest percentage distribution of rare earth elements normalized respect to chondrite with 31.19, 28.35, 19.51 and 8.41% individually. It was observed a marked enrichment of these elements, from west to the east from 26.39 to 111.04 mg/kg and from onshore to offshore from 31.67 to 217.74 mg/kg. The output of the principal component analysis revealed that the REE were mainly of anthropic origin being clearly linked to that of PAHs, metals and organic matter. This, together with their distribution patterns, highlighted the role of the former Bagnoli metallurgical plant in the pollution of the gulf.
Показать больше [+] Меньше [-]Irreversible behavioural impairment of fish starts early: Embryonic exposure to ocean acidification Полный текст
2018
Rodriguez-Dominguez, Almendra | Connell, Sean D. | Baziret, Clement | Nagelkerken, Ivan
Long-term species responses to ocean acidification depend on their sensitivity during different life stages. We tested for sensitivity of juvenile fish behaviour to ocean acidification by exposing eggs to control and elevated CO₂ levels, and translocating offspring between treatments in a reciprocal design. After 12 weeks of exposure, activity, inactivity and anxiety levels of juveniles from control eggs were similar, whether juveniles had experienced elevated CO₂ conditions or not, and this pattern was consistent over time. However, juveniles raised as eggs under elevated CO₂ showed increased anxiety levels compared to those from control eggs. This response was not reversed when CO₂-exposed juveniles were translocated to control conditions. Our findings highlight the value of evaluating fish sensitivities to global change pollutants across different life stages, and indicate that sensitivity during the often-overlooked egg stage can be critical with long-lasting impairment of behaviours that are coupled to individual fitness and population persistence.
Показать больше [+] Меньше [-]Simulated conservative tracer as a proxy for S-metolachlor concentration predictions compared to POCIS measurements in Arcachon Bay Полный текст
2018
Fauvelle, Vincent | Belles, Angel | Budzinski, Hélène | Mazzella, Nicolas | Plus, Martin
The work presented here aims at comparing monitoring of S-metolachlor, the major pesticide in use in the Arcachon Bay (South West of France, transitional coastal area), by chemical analysis (monthly passive sampling) and contaminant dissipation modeling from sources (Mars-2D model). The global strategy consisted in i) identifying the major sources of S-metolachlor to the Bay, ii) monitoring these sources for 12 months, and iii) comparing modeled data in the Bay based on measured inputs, to chemical measurements made inside the Bay along with the 12-month source monitoring. Results first showed that the major S-metolachlor surface inputs to the Arcachon Bay are mainly from one single source. Modeled and measured data were in good agreement at 5 sites in the Bay, both in terms of concentration range and seasonal trends. Modeling thus offers a cost-effective solution for monitoring contaminants in transitional waters, overcoming in addition the technical limitations for measuring pg L⁻¹ or lower levels in coastal waters. However, we highlighted that secondary sources may affect accuracy at local level.
Показать больше [+] Меньше [-]From banana fields to the deep blue: Assessment of chlordecone contamination of oceanic cetaceans in the eastern Caribbean Полный текст
2018
Méndez-Fernandez, Paula | Kiszka, Jeremy J. | Heithaus, Michael R. | Beal, Andria | Vandersarren, Gaëlle | Caurant, Florence | Spitz, Jérôme | Taniguchi, Satie | Montone, Rosalinda C.
In the French West Indies (Caribbean), the insecticide Chlordecone (CLD) has been extensively used to reduce banana weevil (Cosmopolites sordidus) infestations in banana plantations. Previous studies have shown high CLD concentrations in freshwater and coastal communities of the region. CLD concentrations, however, have not yet been assessed in marine top predators. We investigated CLD concentrations in cetacean blubber tissues from Guadeloupe, including Physeter macrocephalus, Lagenodelphis hosei, Stenella attenuata and Pseudorca crassidens. Chlordecone was detected in all blubber samples analysed, with the exception of four P. macrocephalus. Concentrations (range: 1 to 329 ng·g−1 of lipid weight) were, however, lower than those found in species from fresh and brackish water. Ecological factors (open ocean habitat), CLD kinetics, and cetacean metabolism (high or specific enzymatic activity) might explain low concentrations found in cetacean blubber. Future analyses that include internal organ sampling would help to confirm CLD levels observed in this study.
Показать больше [+] Меньше [-]Spreading of drill cuttings and sediment recovery of three exploration wells of different ages, SW Barents Sea, Norway Полный текст
2018
Junttila, Juho | Dijkstra, Noortje | Aagaard-Sørensen, Steffen
Five stations (≤250 m from the well heads) from three exploration wells of different ages from the SW Barents Sea were studied to investigate the spreading of drill cuttings and sediment quality. Two of the wells were drilled before the restriction of use of oil-based drilling fluids (1993). Elevated concentrations of Ba were found in sediments near all the wells with the highest concentrations at ≤60 m from the well head. The thickness of drill cutting layers was between >20 cm (well head) and 2 cm (250 m from the well head). The sediment quality varied from very bad (oldest well) to background (normal) (newer wells). Regulations led to better sediment quality. Metal concentrations from the oldest well suggested that the top 4 cm of the core represents sediment recovery. However, Ba concentrations of the top sediment layer at all the stations of the three wells indicate no physical recovery.
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