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How to select the best tree planting locations to enhance air pollution removal in the MillionTreesNYC initiative Полный текст
2011
Morani, Arianna | Nowak, David J. | Hirabayashi, Satoshi | Calfapietra, Carlo
Highest priority zones for tree planting within New York City were selected by using a planting priority index developed combining three main indicators: pollution concentration, population density and low canopy cover. This new tree population was projected through time to estimate potential air quality and carbon benefits. Those trees will likely remove more than 10 000 tons of air pollutants and a maximum of 1500 tons of carbon over the next 100 years given a 4% annual mortality rate. Cumulative carbon storage will be reduced through time as carbon loss through tree mortality outweighs carbon accumulation through tree growth. Model projections are strongly affected by mortality rate whose uncertainties limit estimations accuracy. Increasing mortality rate from 4 to 8% per year produce a significant decrease in the total pollution removal over a 100 year period from 11 000 tons to 3000 tons.
Показать больше [+] Меньше [-]Developments in greenhouse gas emissions and net energy use in Danish agriculture – How to achieve substantial CO₂ reductions? Полный текст
2011
Dalgaard, T. | Olesen, J.E. | Petersen, S.O. | Petersen, B.M. | Jørgensen, U. | Kristensen, T. | Hutchings, N.J. | Gyldenkærne, S. | Hermansen, J.E.
Developments in greenhouse gas emissions and net energy use in Danish agriculture – How to achieve substantial CO₂ reductions? Полный текст
2011
Dalgaard, T. | Olesen, J.E. | Petersen, S.O. | Petersen, B.M. | Jørgensen, U. | Kristensen, T. | Hutchings, N.J. | Gyldenkærne, S. | Hermansen, J.E.
Greenhouse gas (GHG) emissions from agriculture are a significant contributor to total Danish emissions. Consequently, much effort is currently given to the exploration of potential strategies to reduce agricultural emissions. This paper presents results from a study estimating agricultural GHG emissions in the form of methane, nitrous oxide and carbon dioxide (including carbon sources and sinks, and the impact of energy consumption/bioenergy production) from Danish agriculture in the years 1990–2010. An analysis of possible measures to reduce the GHG emissions indicated that a 50–70% reduction of agricultural emissions by 2050 relative to 1990 is achievable, including mitigation measures in relation to the handling of manure and fertilisers, optimization of animal feeding, cropping practices, and land use changes with more organic farming, afforestation and energy crops. In addition, the bioenergy production may be increased significantly without reducing the food production, whereby Danish agriculture could achieve a positive energy balance.
Показать больше [+] Меньше [-]Developments in greenhouse gas emissions and net energy use in Danish agriculture - How to achieve substantial CO2 reductions? Полный текст
2011
Dalgaard, Tommy | Olesen, Jørgen E. | Petersen, B.M. | Petersen, Søren O. | Jørgensen, Uffe | Kristensen, Troels | Hutchings, Nicholas J. | Gyldenkerne, Steen | Hermansen, J.E.
Greenhouse gas (GHG) emissions from agriculture are a significant contributor to total Danish emissions. Consequently, much effort is currently given to the exploration of potential strategies to reduce agricultural emissions. This paper presents results from a study estimating agricultural GHG emissions in the form of methane, nitrous oxide and carbon dioxide (including carbon sources and sinks, and the impact of energy consumption/bioenergy production) from Danish agriculture in the years 1990-2010. An analysis of possible measures to reduce the GHG emissions indicated that a 50-70% reduction of agricultural emissions by 2050 relative to 1990 is achievable, including mitigation measures in relation to the handling of manure and fertilisers, optimization of animal feeding, cropping practices, and land use changes with more organic farming, afforestation and energy crops. In addition, the bioenergy production may be increased significantly without reducing the food production, whereby Danish agriculture could achieve a positive energy balance.
Показать больше [+] Меньше [-]Inputs of antifouling paint-derived dichlorodiphenyltrichloroethanes (DDTs) to a typical mariculture zone (South China): Potential impact on aquafarming environment Полный текст
2011
Yu, Huan-Yun | Shen, Ru-Lang | Liang, Yan | Cheng, Hefa | Zeng, E. Y. (Eddy Y.)
Existing evidence indicated that dichlorodiphenyltrichloroethane (DDT)-containing antifouling paints were an important source of DDT residues to mariculture zones. However, the magnitude of the impact on aquafarming environment has remained largely unknown. In the present study, the concentrations of DDT and its metabolites (designated as DDXs) were determined in harbor sediment and antifouling paint samples collected from a typical mariculture zone in South China. Compositional and concentration correlation analyses implicated the DDT-containing antifouling paints for fishing boat maintenance as an important source of DDT in the mariculture zone. The annual emission of DDXs to the study region was estimated at 0.58tons/yr. Furthermore, a comparison of the expected DDT loadings in pelagic fish and field measurements indicated that fish feed especially trash fish was a major source of DDTs in the fish body. Nevertheless, the use of DDT-containing antifouling paints should be limited to prevent further deterioration in aquafarming environment.
Показать больше [+] Меньше [-]Combining polar organic chemical integrative samplers (POCIS) with toxicity testing to evaluate pesticide mixture effects on natural phototrophic biofilms Полный текст
2011
Pesce, Stéphane | Morin, Soizic | Lissalde, Sophie | Montuelle, Bernard | Mazzella, Nicolas
Combining polar organic chemical integrative samplers (POCIS) with toxicity testing to evaluate pesticide mixture effects on natural phototrophic biofilms Полный текст
2011
Pesce, Stéphane | Morin, Soizic | Lissalde, Sophie | Montuelle, Bernard | Mazzella, Nicolas
Polar organic chemical integrative samplers (POCIS) are valuable tools in passive sampling methods for monitoring polar organic pesticides in freshwaters. Pesticides extracted from the environment using such methods can be used to toxicity tests. This study evaluated the acute effects of POCIS extracts on natural phototrophic biofilm communities. Our results demonstrate an effect of POCIS pesticide mixtures on chlorophyll a fluorescence, photosynthetic efficiency and community structure. Nevertheless, the range of biofilm responses differs according to origin of the biofilms tested, revealing spatial variations in the sensitivity of natural communities in the studied stream. Combining passive sampler extracts with community-level toxicity tests offers promising perspectives for ecological risk assessment.
Показать больше [+] Меньше [-]Combining polar organic chemical integrative sampler (POCIS) with toxicity testing to evaluate pesticide mixture effects on natural phototrophic biofilms Полный текст
2011
Pesce, Stéphane | Morin, Soizic | Lissalde, Sophie | Montuelle, Bernard | Mazzella, Nicolas | Milieux aquatiques, écologie et pollutions (UR MALY) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Réseaux épuration et qualité des eaux (UR REBX) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Centre Alpin de Recherche sur les Réseaux Trophiques et Ecosystèmes Limniques (CARRTEL) ; Institut National de la Recherche Agronomique (INRA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]) | Cemagref's "PestExpo" Research Program ; French National Office for the Aquatic Environment
International audience
Показать больше [+] Меньше [-]Root porosity and radial oxygen loss related to arsenic tolerance and uptake in wetland plants Полный текст
2011
Li, H. | Ye, Z.H. | Wei, Z.J. | Wong, M.H.
The rates of radial oxygen loss (ROL), root porosity, concentrations of arsenic (As), iron (Fe) and manganese (Mn) in shoot and root tissues and on root surfaces, As tolerances, and their relationships in different wetland plants were investigated based on a hydroponic experiment (control, 0.8, 1.6mg AsL⁻¹) and a soil pot trail (control, 60mg Askg⁻¹). The results revealed that wetland plants showed great differences in root porosity (9–64%), rates of ROL (55–1750mmo1 O₂kg⁻¹ root d.w.d⁻¹), As uptake (e.g., 8.8–151mgkg⁻¹ in shoots in 0.8mg AsL⁻¹ treatment), translocation factor (2.1–47% in 0.8mg AsL⁻¹) and tolerance (29–106% in 0.8mg AsL⁻¹). Wetland plants with higher rates of ROL and root porosity tended to form more Fe/Mn plaque, possess higher As tolerance, higher concentrations of As on root surfaces and a lower As translocation factor so decreasing As toxicity.
Показать больше [+] Меньше [-]Screening of pharmaceuticals and hormones at the regional scale, in surface and groundwaters intended to human consumption Полный текст
2011
Vulliet, Emmanuelle | Cren-Olivé, Cécile
As part of a regional screening to evaluate the risk, for the health of populations, to certain classes of emerging substances, several families of pharmaceuticals and hormones were looked for in waters intended to drinking. Thus, 52 substances were investigated in 71 surface waters and 70 groundwaters. Results indicate that no water was free of pollutants, regardless of its origin (surface or groundwater) and the season of collect. The pharmaceuticals most frequently detected and with the highest concentration levels were salicylic acid, carbamazepine and acetaminophen. Among hormones, testosterone, androstenedione and progesterone were detected in almost all the samples. Globally the groundwaters were less contaminated than surface waters in regards pharmaceuticals frequencies and levels. On the other side, androgens and progestagens were present with comparable frequencies and levels in both compartments. The risk linked to the presence of these substances on human health is discussed.
Показать больше [+] Меньше [-]Distributions of polyhalogenated compounds in Hudson River (New York, USA) fish in relation to human uses along the river Полный текст
2011
Skinner, Lawrence C.
PCBs (as Aroclor concentrations) have been extensively examined in fish along the Hudson River, but other xenobiotic chemicals in fish have had limited assessment. This study determined concentrations and congener distributions of polybrominated diphenyl ethers (PBDEs), polybrominated and polychlorinated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs and PCDD/Fs), and polychlorinated biphenyls (PCBs) in smallmouth bass and striped bass taken from a 385km reach of the Hudson River. Concentrations of PBDEs and PCBs in smallmouth bass, and PCBs in striped bass, were positively related to human uses of the compounds in the basin. Generally low levels of PCDD/Fs were found. One striped bass, however, contained elevated 2,3,7,8-TCDD, indicating exposure to a known source in the adjacent Newark Bay-Passaic River basin. PBDDs were generally below detection. PBDFs were present in four of 18 smallmouth bass, but were not detected in striped bass. Dioxin-like PCBs contribute most to 2,3,7,8-TCDD toxic equivalents in 29 of 30 samples.
Показать больше [+] Меньше [-]Nitrogen critical loads using biodiversity-related critical limits Полный текст
2011
Posch, Maximilian | Aherne, Julian | Hettelingh, Jean-Paul
Critical loads are widely used in the effects-based assessment of emission reduction policies. While the impacts of acidification have diminished, there is increasing concern regarding the effects of nitrogen deposition on terrestrial ecosystems. In this context much attention has been focussed on empirical critical loads as well as simulations with linked geochemistry–vegetation models. Surprisingly little attention has been paid to adapt the widely used simple mass balance approach. This approach has the well-established benefit of easy regional applicability, while incorporating specified critical chemical criteria to protect specified receptors. As plant occurrence/biodiversity is related to both the nutrient and acidity status of an ecosystem, a single abiotic factor (chemical criterion) is not sufficient. Rather than an upper limit for deposition (i.e., critical load), linked nutrient nitrogen and acidity chemical criteria for plant occurrence result in an ‘optimal’ nitrogen and sulphur deposition envelope.
Показать больше [+] Меньше [-]Atmospheric concentrations, sources and gas-particle partitioning of PAHs in Beijing after the 29th Olympic Games Полный текст
2011
Ma, Wanli | Sun, De-Zhi | Shen, Wei-Guo | Yang, Meng | Qi, Hong | Liu, Li-Yan | Shen, Ji-Min | Li, Yi-Fan
A comprehensive sampling campaign was carried out to study atmospheric concentration of polycyclic aromatic hydrocarbons (PAHs) in Beijing and to evaluate the effectiveness of source control strategies in reducing PAHs pollution after the 29th Olympic Games. The sub-cooled liquid vapor pressure (logPL ᵒ)-based model and octanol-air partition coefficient (Kₒₐ)-based model were applied based on each seasonal dateset. Regression analysis among log KP, logPL ᵒ and log Kₒₐ exhibited high significant correlations for four seasons. Source factors were identified by principle component analysis and contributions were further estimated by multiple linear regression. Pyrogenic sources and coke oven emission were identified as major sources for both the non-heating and heating seasons. As compared with literatures, the mean PAH concentrations before and after the 29th Olympic Games were reduced by more than 60%, indicating that the source control measures were effective for reducing PAHs pollution in Beijing.
Показать больше [+] Меньше [-]The effect of atmospheric thermal conditions and urban thermal pollution on all-cause and cardiovascular mortality in Bangladesh Полный текст
2011
Burkart, Katrin | Schneider, Alexandra | Breitner, Susanne | Khan, Md. Mobarak Hossain | Krämer, Alexander | Endlicher, Wilfried
This study assessed the effect of temperature and thermal atmospheric conditions on all-cause and cardiovascular mortality in Bangladesh. In particular, differences in the response to elevated temperatures between urban and rural areas were investigated. Generalized additive models (GAMs) for daily death counts, adjusted for trend, season, day of the month and age were separately fitted for urban and rural areas. Breakpoint models were applied for determining the increase in mortality above and below a threshold (equivalent) temperature. Generally, a ’V’-shaped (equivalent) temperature–mortality curve with increasing mortality at low and high temperatures was observed. Particularly, urban areas suffered from heat-related mortality with a steep increase above a specific threshold. This adverse heat effect may well increase with ongoing urbanization and the intensification of the urban heat island due to the densification of building structures. Moreover, rising temperatures due to climate change could aggravate thermal stress.
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