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Forests under climate change and air pollution: Gaps in understanding and future directions for research 全文
2012
Matyssek, R. | Wieser, G. | Calfapietra, C. | de Vries, W. | Dizengremel, P. | Ernst, D. | Jolivet, Y. | Mikkelsen, T.N. | Mohren, G.M.J. | Le Thiec, D. | Tuovinen, J.-P. | Weatherall, A. | Paoletti, E.
Forests under climate change and air pollution: Gaps in understanding and future directions for research 全文
2012
Matyssek, R. | Wieser, G. | Calfapietra, C. | de Vries, W. | Dizengremel, P. | Ernst, D. | Jolivet, Y. | Mikkelsen, T.N. | Mohren, G.M.J. | Le Thiec, D. | Tuovinen, J.-P. | Weatherall, A. | Paoletti, E.
Forests in Europe face significant changes in climate, which in interaction with air quality changes, may significantly affect forest productivity, stand composition and carbon sequestration in both vegetation and soils. Identified knowledge gaps and research needs include: (i) interaction between changes in air quality (trace gas concentrations), climate and other site factors on forest ecosystem response, (ii) significance of biotic processes in system response, (iii) tools for mechanistic and diagnostic understanding and upscaling, and (iv) the need for unifying modelling and empirical research for synthesis. This position paper highlights the above focuses, including the global dimension of air pollution as part of climate change and the need for knowledge transfer to enable reliable risk assessment. A new type of research site in forest ecosystems (“supersites”) will be conducive to addressing these gaps by enabling integration of experimentation and modelling within the soil-plant-atmosphere interface, as well as further model development.
显示更多 [+] 显示较少 [-]Forests under climate change and air pollution: Gaps in understanding and future directions for research 全文
2012
Matyssek, R. | Wieser, G. | Calfapietra, C. | de Vries, W. | Dizengremel, Pierre | Ernst, D. | Jolivet, Yves | Mikkelsen, T. N. | Mohren, G. M. J. | Le Thiec, Didier | Tuovinen, J. -P. | Weatherall, A. | Paoletti, E. | Technische Universität Munchen - Technical University Munich - Université Technique de Munich (TUM) | Dept Alpine Timberline Ecophysiol ; Federal Office and Research Centre for Forests | Natl Res Council ; Inst Agroenvironm & Forest Biol | Environm Syst Anal Grp ; Wageningen University and Research [Wageningen] (WUR) | Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL) | Inst Biochem Plant Pathol ; Helmholtz Zentrum München = German Research Center for Environmental Health (HMGU) | Biosystems Division [Roskilde] ; Risø National Laboratory for Sustainable Energy (Risø DTU) ; Danmarks Tekniske Universitet = Technical University of Denmark (DTU)-Danmarks Tekniske Universitet = Technical University of Denmark (DTU) | Forest Ecology and Forest Management Group [Wageningen] ; Centre for Ecosystem Studies [Wageningen] ; Wageningen University and Research [Wageningen] (WUR)-Wageningen University and Research [Wageningen] (WUR) | Finnish Meteorological Institute (FMI) | Natl Sch Forestry ; Univ Cumbria | National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR) | EU Commission
Forests in Europe face significant changes in climate, which in interaction with air quality changes, may significantly affect forest productivity, stand composition and carbon sequestration in both vegetation and soils. Identified knowledge gaps and research needs include: (i) interaction between changes in air quality (trace gas concentrations), climate and other site factors on forest ecosystem response, (ii) significance of biotic processes in system response, (iii) tools for mechanistic and diagnostic understanding and upscaling, and (iv) the need for unifying modelling and empirical research for synthesis. This position paper highlights the above focuses, including the global dimension of air pollution as part of climate change and the need for knowledge transfer to enable reliable risk assessment. A new type of research site in forest ecosystems ("supersites") will be conducive to addressing these gaps by enabling integration of experimentation and modelling within the soil-plant-atmosphere interface, as well as further model development. (C) 2011 Elsevier Ltd. All rights reserved.
显示更多 [+] 显示较少 [-]Gene expression of heat shock protein 70, interleukin-1β and tumor necrosis factor α as tools to identify immunotoxic effects on Xenopus laevis: A dose–response study with benzo[a]pyrene and its degradation products 全文
2012
Martini, Federica | Fernández, Carlos | Tarazona, José V. | Pablos, M Victoria
Gene expression of heat shock protein 70, interleukin-1β and tumor necrosis factor α as tools to identify immunotoxic effects on Xenopus laevis: A dose–response study with benzo[a]pyrene and its degradation products 全文
2012
Martini, Federica | Fernández, Carlos | Tarazona, José V. | Pablos, M Victoria
The exposure to benzo[a]pyrene (B[a]P) results in an alteration of immune function in mammals and fish, and the analysis of cytokine mRNA levels has been suggested for predicting the immunomodulatory potential of chemicals. To obtain evidence of the innate immune responses to B[a]P in Xenopus laevis, the present study monitored the mRNA expression of interleukin 1-β (IL-1β), tumor necrosis factor α (TNF-α) and heat shock protein 70 (HSP70) in a laboratorial exposure. Tadpoles exposed to 8.36, 14.64, 89.06 and 309.47 μg/L of B[a]P,were used for detecting hsp70, IL-1β and TNF-α mRNA induction. A dose–response increase in the expression of hsp70 and IL-1β mRNA was found. The results of this study confirmed the use of hsp70 and IL-1β, but not TNF-α, as sensitive indicators of immunotoxic effect of B[a]P in X. laevis. Further research would be required for the validation of these endpoints.
显示更多 [+] 显示较少 [-]Gene expression of heat shock protein 70, interleukin-1β and tumor necrosis factor α as tools to identify immunotoxic effects on Xenopus laevis A dose-response study with benzo[a]pyrene and its degradation products 全文
2012
Martini, F. | Fernández, Carlos | Tarazona, J. V. | Pablos, María Victoria | Pablos, María Victoria [0000-0003-2955-5846]
The exposure to benzo[a]pyrene (B[a]P) results in an alteration of immune function in mammals and fish, and the analysis of cytokine mRNA levels has been suggested for predicting the immunomodulatory potential of chemicals. To obtain evidence of the innate immune responses to B[a]P in Xenopus laevis, the present study monitored the mRNA expression of interleukin 1-β (IL-1β), tumor necrosis factor α (TNF-α) and heat shock protein 70 (HSP70) in a laboratorial exposure. Tadpoles exposed to 8.36, 14.64, 89.06 and 309.47 μg/L of B[a]P,were used for detecting hsp70, IL-1β and TNF-α mRNA induction. A dose-response increase in the expression of hsp70 and IL-1β mRNA was found. The results of this study confirmed the use of hsp70 and IL-1β, but not TNF-α, as sensitive indicators of immunotoxic effect of B[a]P in X. laevis. Further research would be required for the validation of these endpoints. © 2011 Elsevier Ltd. All rights reserved.
显示更多 [+] 显示较少 [-]Mutagenicity assessment of aerosols in emissions from wood combustion in Portugal 全文
2012
Vu, B. | Alves, C.A. | Gonçalves, C. | Pio, C. | Gonçalves, F. | Pereira, R.
Mutagenicity assessment of aerosols in emissions from wood combustion in Portugal 全文
2012
Vu, B. | Alves, C.A. | Gonçalves, C. | Pio, C. | Gonçalves, F. | Pereira, R.
Polycyclic aromatic hydrocarbon (PAH) extracts of fine particles (PM₂.₅) collected from combustion of seven wood species and briquettes were tested for mutagenic activities using Ames test with Salmonella typhimurium TA98 and TA100. The woods were Pinus pinaster (maritime pine), Eucalyptus globulus (eucalypt), Quercus suber (cork oak), Acacia longifolia (golden wattle), Quercus faginea (Portuguese oak), Olea europea (olive), and Quercus ilex rotundifolia (Holm oak). Burning experiments were done using woodstove and fireplace, hot start and cold start conditions. A mutagenic response was recorded for all species except golden wattle, maritime pine, and briquettes. The mutagenic extracts were not correlated with high emission factors of carcinogenic PAHs. These extracts were obtained both from two burning appliances and start-up conditions. However, fireplace seemed to favour the occurrence of mutagenic emissions. The negative result recorded for golden wattle was interesting, in an ecological point of view, since after confirmation, this invasive species, can be recommended for domestic use.
显示更多 [+] 显示较少 [-]Mutagenicity assessment of aerosols in emissions from wood combustion in Portugal 全文
2012
Vu, B. | Alves, C. A. | Gonçalves, C. | Pio, C. | Gonçalves, F. | Pereira, R.
Polycyclic aromatic hydrocarbon (PAH) extracts of fine particles (PM(2.5)) collected from combustion of seven wood species and briquettes were tested for mutagenic activities using Ames test with Salmonella typhimurium TA98 and TA100. The woods were Pinus pinaster (maritime pine), Eucalyptus globulus (eucalypt), Quercus suber (cork oak), Acacia longifolia (golden wattle), Quercus faginea (Portuguese oak), Olea europea (olive), and Quercus ilex rotundifolia (Holm oak). Burning experiments were done using woodstove and fireplace, hot start and cold start conditions. A mutagenic response was recorded for all species except golden wattle, maritime pine, and briquettes. The mutagenic extracts were not correlated with high emission factors of carcinogenic PAHs. These extracts were obtained both from two burning appliances and start-up conditions. However, fireplace seemed to favour the occurrence of mutagenic emissions. The negative result recorded for golden wattle was interesting, in an ecological point of view, since after confirmation, this invasive species, can be recommended for domestic use. | published
显示更多 [+] 显示较少 [-]Arsenic fractionation in mine spoils 10 years after aided phytostabilization 全文
2012
Kumpiene, Jurate | Fitts, Jeffrey P. | Mench, Michel
Arsenic fractionation in mine spoils 10 years after aided phytostabilization 全文
2012
Kumpiene, Jurate | Fitts, Jeffrey P. | Mench, Michel
Aided phytostabilization using a combination of compost, zerovalent iron grit and coal fly ash (CZA) amendments and revegetation effectively promoted the biological recovery of mining spoils generated at a gold mine in Portugal. Selective dissolution of spoil samples in combination with solid phase characterization using microbeam X-ray absorption near edge structure (μXANES) spectroscopy and microbeam X-ray fluorescence (μXRF) mapping were used to assess As associations in spoils ten years after CZA treatment. The results show that As preferentially associates with poorly crystalline Fe-oxyhydroxides as opposed to crystalline Fe-(oxyhydr)oxide phases. The crystalline Fe(III)-phases dominated in the treated spoil and exceeded those of the untreated spoil three-fold, but only 2.6–6.8% of total As was associated with this fraction. Correlation maps of As:Fe reveal that As in the CZA-treated spoils is primarily contained in surface coatings as precipitates and sorbates. Arsenic binding with poorly crystalline Fe-oxyhydroxides did not inhibit As uptake by plants.
显示更多 [+] 显示较少 [-]Arsenic fractionation in mine spoils 10 years after aided phytostabilization 全文
2012
Kumpiene, Jurate | Fitts, Jeffrey P. | Mench, Michel | Division of Waste Science and Technology ; Luleå University of Technology = Luleå Tekniska Universitet (LUT) | Environmental Sciences Department ; Brookhaven National Laboratory [Upton, NY] (BNL) ; UT-Battelle, LLC-Stony Brook University [SUNY] (SBU) ; State University of New York (SUNY)-State University of New York (SUNY)-U.S. Department of Energy [Washington] (DOE)-UT-Battelle, LLC-Stony Brook University [SUNY] (SBU) ; State University of New York (SUNY)-State University of New York (SUNY)-U.S. Department of Energy [Washington] (DOE) | Biodiversité, Gènes & Communautés (BioGeCo) ; Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB)
International audience | Aided phytostabilization using a combination of compost, zerovalent iron grit and coal fly ash (CZA) amendments and revegetation effectively promoted the biological recovery of mining spoils generated at a gold mine in Portugal. Selective dissolution of spoil samples in combination with solid phase characterization using microbeam X-ray absorption near edge structure (μXANES) spectroscopy and microbeam X-ray fluorescence (μXRF) mapping were used to assess As associations in spoils ten years after CZA treatment. The results show that As preferentially associates with poorly crystalline Fe-oxyhydroxides as opposed to crystalline Fe-(oxyhydr)oxide phases. The crystalline Fe(III)-phases dominated in the treated spoil and exceeded those of the untreated spoil three-fold, but only 2.6–6.8% of total As was associated with this fraction. Correlation maps of As:Fe reveal that As in the CZA-treated spoils is primarily contained in surface coatings as precipitates and sorbates. Arsenic binding with poorly crystalline Fe-oxyhydroxides did not inhibit As uptake by plants.
显示更多 [+] 显示较少 [-]Modeling the kinetics of microbial degradation of deicing chemicals in porous media under flow conditions 全文
2012
Wehrer, Markus | Jaesche, Philipp | Totsche, Kai Uwe
A quantitative knowledge of the fate of deicing chemicals in the subsurface can be provided by joint analysis of lab experiments with numerical simulation models. In the present study, published experimental data of microbial degradation of the deicing chemical propylene glycol (PG) under flow conditions in soil columns were simulated inversely to receive the parameters of degradation. We evaluated different scenarios of an advection-dispersion model including different terms for degradation, such as zero order, first order and inclusion of a growing and decaying biomass for their ability to explain the data. The general break-through behavior of propylene glycol in soil columns can be simulated well using a coupled model of solute transport and degradation with growth and decay of biomass. The susceptibility of the model to non-unique solutions was investigated using systematical forward and inverse simulations. We found that the model tends to equifinal solutions under certain conditions.
显示更多 [+] 显示较少 [-]Variability of indoor and outdoor VOC measurements: An analysis using variance components 全文
2012
Jia, Chunrong | Batterman, Stuart A. | Relyea, George E.
This study examines concentrations of volatile organic compounds (VOCs) measured inside and outside of 162 residences in southeast Michigan, U.S.A. Nested analyses apportioned four sources of variation: city, residence, season, and measurement uncertainty. Indoor measurements were dominated by seasonal and residence effects, accounting for 50 and 31%, respectively, of the total variance. Contributions from measurement uncertainty (<20%) and city effects (<10%) were small. For outdoor measurements, season, city and measurement variation accounted for 43, 29 and 27% of variance, respectively, while residence location had negligible impact (<2%). These results show that, to obtain representative estimates of indoor concentrations, measurements in multiple seasons are required. In contrast, outdoor VOC concentrations can use multi-seasonal measurements at centralized locations. Error models showed that uncertainties at low concentrations might obscure effects of other factors. Variance component analyses can be used to interpret existing measurements, design effective exposure studies, and determine whether the instrumentation and protocols are satisfactory.
显示更多 [+] 显示较少 [-]High levels of DDT in breast milk: Intake, risk, lactation duration, and involvement of gender 全文
2012
Bouwman, Hindrik | Kylin, Henrik | Sereda, Barbara | Bornman, Riana
We investigated presence and levels of DDT in 163 breast milk samples from four South African villages where, in three of them, malaria is controlled with DDT-sprayed indoors. Mean ΣDDT levels in breast milk were 18, 11, and 9.5 mg/kg mf (milk fat) from the three DDT-sprayed villages, respectively, including the highest ΣDDT level ever reported for breast milk from South Africa (140 mg/kg mf). Understanding the causes for these differences would be informative for exposure reduction intervention. The Provisional Tolerable Daily Intake (PTDI) for DDT by infants, and the Maximum Residue Limit (MRL) were significantly exceeded. DDT had no effect on duration of lactation. There were indications (not significant) from DDT-sprayed villages that first-born female infants drink milk with more ΣDDT than first-born male infants, and vice versa for multipara male and female infants, suggesting gender involvement on levels of DDT in breast milk – requiring further investigation.
显示更多 [+] 显示较少 [-]Rapid recovery of stem increment in Norway spruce at reduced SO₂ levels in the Harz Mountains, Germany 全文
2012
Hauck, Markus | Zimmermann, Jorma | Jacob, Mascha | Dulamsuren, Choimaa | Bade, Claudia | Ahrends, Bernd | Leuschner, Christoph
Tree-ring width of Picea abies was studied along an altitudinal gradient in the Harz Mountains, Germany, in an area heavily affected by SO₂-related forest decline in the second half of the 20th century. Spruce trees of exposed high-elevation forests had earlier been shown to have reduced radial growth at high atmospheric SO₂ levels. After the recent reduction of the SO₂ load due to clean air acts, we tested the hypothesis that stem growth recovered rapidly from the SO₂ impact. Our results from two formerly damaged high-elevation spruce stands support this hypothesis suggesting that the former SO₂-related spruce decline was primarily due to foliar damage and not to soil acidification, as the deacidification of the (still acidic) soil would cause a slow growth response. Increasing temperatures and deposited N accumulated in the topsoil are likely additional growth-promoting factors of spruce at high elevations after the shortfall of SO₂ pollution.
显示更多 [+] 显示较少 [-]Stream habitat structure influences macroinvertebrate response to pesticides 全文
2012
Rasmussen, Jes Jessen | Wiberg-Larsen, Peter | Baattrup-Pedersen, Annette | Friberg, Nikolai | Kronvang, Brian
Agricultural pesticides continue to impair surface water ecosystems, although there are few assessments of interactions with other modifications such as fine sediment and physical alteration for flood drainage. We, therefore, surveyed pesticide contamination and macroinvertebrates in 14 streams along a gradient of expected pesticide exposure using a paired-reach approach to differentiate effects between physically modified and less modified sites. Apparent pesticides effects on the relative abundance of SPEcies At Risk (SPEAR) were increased at sites with degraded habitats primarily due to the absence of species with specific preferences for hard substrates. Our findings highlight the importance of physical habitat degradation in the assessment and mitigation of pesticide risk in agricultural streams.
显示更多 [+] 显示较少 [-]The growth pattern and fuel life cycle analysis of the electricity consumption of Hong Kong 全文
2012
To, W.M. | Lai, T.M. | Lo, W.C. | Lam, K.H. | Chung, W.L.
As the consumption of electricity increases, air pollutants from power generation increase. In metropolitans such as Hong Kong and other Asian cities, the surge of electricity consumption has been phenomenal over the past decades. This paper presents a historical review about electricity consumption, population, and change in economic structure in Hong Kong. It is hypothesized that the growth of electricity consumption and change in gross domestic product can be modeled by 4-parameter logistic functions. The accuracy of the functions was assessed by Pearson's correlation coefficient, mean absolute percent error, and root mean squared percent error. The paper also applies the life cycle approach to determine carbon dioxide, methane, nitrous oxide, sulfur dioxide, and nitrogen oxide emissions for the electricity consumption of Hong Kong. Monte Carlo simulations were applied to determine the confidence intervals of pollutant emissions. The implications of importing more nuclear power are discussed.
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