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Daytime Ozone Variation in Surface Air in a Subtropical Mangrove Estuary at Manakudy, South India
2018
Krishna Sharma, R. | Chithambarathau, T | Elampari, K. | Nagaveena, S.
Surface ozone (SOZ) can be very harmful if it exceeds the threshold limit. It can accumulate over sea and can return back to the land along with the breeze. Rural and vegetation rich areas often record elevated levels of surface ozone because of the variations in Volatile Organic Compound (VOC) levels, wind velocity and direction. Similarly methane is also an important greenhouse gas and plays a vital role in the atmospheric budget. In this work, ozone and methane levels measured during daytime in a mangrove estuary near Manakudy(8.0911 N, 77.477 E),kanyakumari, South India for a period of ten months from March 2014 to December 2014 are analyzed.SOZ showed an imprecise diurnal pattern with an early morning peak whereas methane recorded an apparent diurnality. The maximum value of SOZ was around 50 ppb. Summer months recorded high levels of SOZ followed by Southwest monsoon (SWM) and Northeast monsoon (NEM).High levels of methane were found in SWM followed by NEM and low concentration during summer. The correlation between SOZ and methane was found as r = -0.257, p
显示更多 [+] 显示较少 [-]Anthropogenic share of metal contents in soils of urban areas
2018
Fazeli, G. | Karbassi, A.R. | khoramnejadian, Sh. | Nasrabadi, T.
In the present investigation, 41 soil samples were subjected to single step chemical partitioning to assess the lithogenic and non-lithogenic portions of metals in Tehran's soils. The share of various studied metals in the anthropogenic portion ranges from as low as 0.2% to as high as 85% of bulk concentration. Geo-accumulation index (Igeo) showed that Cd falls within "heavily contaminated" soils. It might be inferred that Ni, Cu, Cr, Zn, Co and Ca fall within "Deficient to minimal" class in accordance with enrichment factor (EF) classification.. Enrichment factor values (to some extents) match with the chemical partition studies results (except for Ni and Cr). The very low Ca content of soil samples could be indicative of low biological productivity in the Tehran's soil. Also the very low concentrations of Mn could be indicative of reducing environment in soils of Tehran.
显示更多 [+] 显示较少 [-]Contaminants in Atlantic walruses Part 2: Relationships with endocrine and immune systems
2018
Routti, Heli | Diot, Beatrice | Panti, Cristina | Duale, Nur | Fossi, Maria Cristina | Harju, Mikael | Kovacs, Kit M. | Lydersen, Christian | Scotter, Sophie | Villanger, Gro Dehli | Bourgeon, Sophie
acceptedVersion
显示更多 [+] 显示较少 [-]Indoor PM2.5 in an urban zone with heavy wood smoke pollution: The case of Temuco, Chile
2018
Jorquera, Héctor | Barraza, Francisco | Heyer, Johanna | Valdivia, Gonzalo | Schiappacasse Poyanco, Luis | Montoya, Lupita D.
Temuco is a mid-size city representative of severe wood smoke pollution in southern Chile; however, little is known about the indoor air quality in this region. A field measurement campaign at 63 households in the Temuco urban area was conducted in winter 2014 and is reported here. In this study, indoor and outdoor (24-hr) PM2.5 and its elemental composition were measured and compared. Infiltration parameters and outdoor/indoor contributions to indoor PM2.5 were also determined. A statistical evaluation of how various air quality interventions and household features influence indoor PM2.5 was also performed. This study determined median indoor and outdoor PM2.5 concentrations of 44.4 and 41.8 μg/m3, respectively. An average infiltration factor (0.62 ± 0.06) was estimated using sulfur as a tracer species. Using a simple mass balance approach, median indoor and outdoor contributions to indoor PM2.5 concentrations were then estimated as 12.5 and 26.5 μg/m3, respectively; therefore, 68% of indoor PM2.5 comes from outdoor infiltration. This high percentage is due to high outdoor pollution and relatively high household air exchange rates (median: 1.06 h−1). This study found that S, Br and Rb were dominated by outdoor contributions, while Si, Ca, Ti, Fe and As originated from indoor sources. Using continuous indoor and outdoor PM2.5 measurements, a median indoor source strength of 75 μg PM2.5/min was estimated for the diurnal period, similar to literature results. For the evening period, the median estimate rose to 135 μg PM2.5/min, reflecting a more intense wood burning associated to cooking and space heating at night. Statistical test results (at the 90% confidence level) support the ongoing woodstove replacement program (reducing emissions) and household weatherization subsidies (reducing heating demand) for improving indoor air quality in southern Chile, and suggest that a cookstove improvement program might be helpful as well. In the city of Temuco, southern Chile, 68% of indoor PM2.5 comes from severe outdoor pollution due to intensive wood burning, enhanced by poor household building standards and fuel poverty
显示更多 [+] 显示较少 [-]Development of a flux DMT with integrated adsorptive stripping voltammetry for free metal ions detection in solution
2018
Janot, Noemie | Rotureau, Elise | Pinheiro, Jose Paulo
Development of a flux DMT with integrated adsorptive stripping voltammetry for free metal ions detection in solution. Interfaces Against Pollution
显示更多 [+] 显示较少 [-]Solid-solution partitioning of Rare Earth Elements in mine-tailings and soils in China: experimental results and multi-surface modelling
2018
Janot, Noemie | Huot, Hermine | Otero-Fariña, Alba | Leguédois, Sophie | Groenenberg, Jan E.
Solid-solution partitioning of Rare Earth Elements in mine-tailings and soils in China: experimental results and multi-surface modelling. Interfaces Against Pollution
显示更多 [+] 显示较少 [-]Resiliency of a healthy fish stock to recruitment losses from oil spills
2018
Carroll, JoLynn | Vikebø, Frode Bendiksen | Howell, Daniel | Broch, Ole Jacob | Nepstad, Raymond | Augustine, Starrlight | Skeie, Geir Morten | Bast, Radovan
We simulate oil spills of 1500 and 4500 m3/day lasting 14, 45, and 90 days in the spawning grounds of the commercial fish species, Northeast Arctic cod. Modeling the life history of individual fish eggs and larvae, we predict deviations from the historical pattern of recruitment to the adult population due to toxic oil exposures. Reductions in survival for pelagic stages of cod were 0-10%, up to a maximum of 43%. These reductions resulted in a decrease in adult cod biomass of <3% for most scenarios, up to a maximum of 12%. In all simulations, the adult population remained at full reproductive potential with a sufficient number of juveniles surviving to replenish the population. The diverse age distribution helps protect the adult cod population from reductions in a single year's recruitment after a major oil spill. These results provide insights to assist in managing oil spill impacts on fisheries. | publishedVersion
显示更多 [+] 显示较少 [-]Long term organochlorine soil pollution in agriculture: The lessons learnt from the Chlordecone pollution in French West Indies
2018
Lesueur Jannoyer, Magalie | Cattan, Philippe | Mottes, Charles | Clostre, Florence | Della Rossa, Pauline | Woignier, Thierry
The French West Indies face nowadays a diffuse and long term environmental pollution related to historical use of organochlorine insecticide in banana fields, Chlordecone (CLD). Due to its stability, it now pollutes soil, waters, agricultural products and leads to a global exposure of people and ecosystems. We wonder how to manage such a complex pollution system involving all environmental compartments, linked each other. For that, we have been conducting research studies for more than 15 years in the field of agronomy and environment to explore the fate of the molecule in the environment, the impact on food safety, and also the remediation options. Three main points are addressed: i) how to characterize the pollution and to make easier the diagnosis? ii) how to assess the impacts on environmental compartments and agricultural products? iii) How to manage the pollution? The tools we developed make a diagnosis of such pollution easier at different scales (field, farm, watershed, and territory). We built monitoring support systems for the water quality of rivers with models helping to understand variability of water contamination. We built also decision support systems to farmers to manage their soil pollution and choose the crops that will ensure food security. Now CLD content of local crop products on the market complies with the Maximum Residue Limit. Management is more complex for animal products, and further investigations are needed. We investigated alternative solution to enhance CLD soil sequestration, using physical properties of French West Indies volcanic soil and organic matter amendment. Increased organic matter content in soil reduced drastically the CLD transfer from soil to water, but this effect was not perennial and amendment had to be regularly applied. Our results show that an integrative approach is needed to build efficient policies to manage such pollution than to prevent new ones.
显示更多 [+] 显示较少 [-]Assessing agricultural soil pollution risks from organic waste recycling: informing regional participatory waste management
2018
Wassenaar, Tom | Feder, Frédéric | Doelsch, Emmanuel
The well-informed recycling of organic waste to agricultural land becomes increasingly desirable in dynamic, developing regions worldwide. Pursuing locally optimal benefit-risk ratios, agro-environmental research in support of OW recycling does not focus on avoiding contamination perse, but on the control of dynamics, in soil and other environmental compartments, in order not to exceed risk thresholds. We present a series of empirical research efforts that inform decision making in regions under OW pressure on OW-contained trace contaminant fate under local conditions. Their results illustrate that the present understanding of trace elements fate allows for the ex-ante assessment of fate under specific use scenarios and local conditions, with a limited set of simplifications. A well-established set of analytical tools provides the information required by such assessments. Understanding of OW-borne organic contaminants is less advanced, but the present capacity to project fate under local conditions does allow for the approximate appreciation of risk levels, the major benefit of which is to focus subsequent research on substances of concern. Ongoing long-term field trials may critically advance our understanding of OW-borne contaminant fate in soil. Developing a reasonable capacity to assess biological contaminant fate is one of its priorities.
显示更多 [+] 显示较少 [-]Solid-solution partitioning of Rare Earth Elements in mine-tailings and soils in China: experimental results and multi-surface modelling
2018
Janot, Noemie | Huot, Hermine | Otero-Fariña, Alba | Leguédois, Sophie | Groenenberg, Jan E. | Laboratoire Sols et Environnement (LSE) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL) | Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC) ; Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Terre et Environnement de Lorraine (OTELo) ; Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS) | Centre National de la Recherche Scientifique (CNRS) | Sun Yat-Sen University (SYSU) | Wageningen University and Research [Wageningen] (WUR)
International audience | Solid-solution partitioning of Rare Earth Elements in mine-tailings and soils in China: experimental results and multi-surface modelling. Interfaces Against Pollution
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