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21.
Forest Fires and Climate Change in the 21ST Century 总被引:3,自引:0,他引:3
M. D. Flannigan B. D. Amiro K. A. Logan B. J. Stocks B. M. Wotton 《Mitigation and Adaptation Strategies for Global Change》2006,11(4):847-859
Fire is the major stand-renewing disturbance in the circumboreal forest. Weather and climate are the most important factors
influencing fire activity and these factors are changing due to human-caused climate change. This paper discusses and synthesises
the current state of fire and climate change research and the potential direction for future studies on fire and climate change.
In the future, under a warmer climate, we expect more severe fire weather, more area burned, more ignitions and a longer fire
season. Although there will be large spatial and temporal variation in the fire activity response to climate change. This
field of research allows us to better understand the interactions and feedbacks between fire, climate, vegetation and humans
and to identify vulnerable regions. Lastly, projections of fire activity for this century can be used to explore options for
mitigation and adaptation. 相似文献
22.
Phototransformation of methabenthiazuron in the presence of nitrate and nitrite ions 总被引:2,自引:0,他引:2
The influence of nitrate and nitrite ions on the degradation of methabenzthiazuron upon irradiation using artificial solar light has been investigated. The rate of degradation of methabenzthiazuron (1 microM) was accelerated by NO3- (0.1 mM) by a factor of 10. The irradiation of methabenzthiazuron (0.1 mM) in the presence of NO3- (1 mM) or NO2- (0.1 mM) yielded numerous intermediary photoproducts. Mineralization was achieved after prolonged exposure. Some were identified with the help of LC-ESI-MS and flow injection APCI-MS techniques. Both oxidations of the aromatic ring and of the urea chain were observed. The former started by hydroxylation of the ring. Further oxidation of the ring led to cleavage of the benzenic ring with formation of dialdehydic, diacidic and anhydric compounds. Complete removal of the lateral urea chain took place subsequently to demethylation of the terminal methyl group and loss of the CO-NH2 group. Nitration was a minor process. This work shows that the photodegradation of methabenzthiazuron in the presence of nitrate or nitrite ions is highly non-specific. 相似文献
23.
The photochemical behaviour of several chlorinated pesticides, namely 4-chloro-2-methylphenoxyacetic acid (MCPA), dichlorophen (DCPH), flamprop-methyl (FPM) and vinclozolin (VCZ) is studied on various kinds of sand: Fontainebleau sand (almost pure silica), Touggourt sand (coloured sand from Sahara) and Jijel sand (dark marine sand). The photodegradation of MCPA is more rapid on Fontainebleau sand than on the two others, because the former is almost colourless pure silica and the others adsorb on the internal surface of the reactor. The degradation rate decreases in the order MCPA, DCPH, FPM, VCZ. The main products identified are 4-chloro-2-methylphenol with MCPA and reduction product with DCPH. 相似文献
24.
The Ontario Ministry of Environment (MOE) recently participated in a joint Canadian/U.S. program to monitor the behavior and environmental impact of prescribed fires. Air, soil and ash samples were collected at the burn sites and analyzed for chlorinated dibenzo-p-dioxins (CDD) and dibenzofurans (CDF). Preliminary results indicated that larger air sample volumes were required. 相似文献
25.
Amniotic fluid cholinesterases tested on polyacrylamide gel and rapidly adhering cell analysis were compared in their efficiency at diagnosing fetal neural tube defects in three cases where the alphafetoprotein results were equivocal. While rapidly adhering cells were also equivocal, the cholinesterases consistently gave a clear indication of fetal abnormality. 相似文献
26.
Nicolas Breysse Gaelle Vial Lauriane Pattingre Bernadette C. Ossendorp Karin Mahieu Hermine Reich 《Journal of environmental science and health. Part. B》2018,53(6):352-365
ABSTRACTProposals to update the methodology for the international estimated short-term intake (IESTI) equations were made during an international workshop held in Geneva in 2015. Changes to several parameters of the current four IESTI equations (cases 1, 2a, 2b, and 3) were proposed. In this study, the overall impact of these proposed changes on estimates of short-term exposure was studied using the large portion data available in the European Food Safety Authority PRIMo model and the residue data submitted in the framework of the European Maximum Residue Levels (MRL) review under Article 12 of Regulation (EC) No 396/2005. Evaluation of consumer exposure using the current and proposed equations resulted in substantial differences in the exposure estimates; however, there were no significant changes regarding the number of accepted MRLs. For the different IESTI cases, the median ratio of the new versus the current equation is 1.1 for case 1, 1.4 for case 2a, 0.75 for case 2b, and 1 for case 3. The impact, expressed as a shift in the IESTI distribution profile, indicated that the 95th percentile IESTI shifted from 50% of the acute reference dose (ARfD) with the current equations to 65% of the ARfD with the proposed equations. This IESTI increase resulted in the loss of 1.2% of the MRLs (37 out of 3110) tested within this study. At the same time, the proposed equations would have allowed 0.4% of the MRLs (14 out of 3110) that were rejected with the current equations to be accepted. The commodity groups that were most impacted by these modifications are solanacea (e.g., potato, eggplant), lettuces, pulses (dry), leafy brassica (e.g., kale, Chinese cabbage), and pome fruits. The active substances that were most affected were fluazifop-p-butyl, deltamethrin, and lambda-cyhalothrin. 相似文献
27.
David Browne Bernadette O'Regan Richard Moles 《Journal of Environmental Planning and Management》2008,51(3):447-470
The objective of this paper is to compare the carbon emissions produced as a result of product consumption by the residents of an Irish city-region, that is Limerick City and its environs. The resulting carbon footprints are used to compare imports of food items, manufactured products and construction materials with domestic production as well as changes between 1996 and 2002. The total ecological footprints (EF) associated with product consumption are also calculated by aggregating the theoretical land required to sequester carbon emissions and the terrestrial land area appropriated for agricultural production and industrial activity. It is suggested that this approach be used to allocate producer or consumer responsibility for environmental impacts from trade. 相似文献
28.
Alex H.S. Chik Melissa B. Glier Mark Servos Chand S. Mangat Xiao-Li Pang Yuanyuan Qiu Patrick M. DAoust Jean-Baptiste Burnet Robert Delatoll Sarah Dorner Qiudi Geng John P. Giesy Robert Mike McKay Michael R. Mulvey Natalie Prystajecky Nivetha Srikanthan Yuwei Xie Bernadette Conant Steve E. Hrudey 《环境科学学报(英文版)》2021,33(9):218-229
29.
In recent years there has been growing interest in Britain in the possibility of opting for underground, rather than surface, extraction methods for low value aggregates. Such a policy would lead to reduced environmental impact and could, under particular circumstances, offer cost advantages to the producer. An assured supply of aggregates at acceptable cost is essential to any modern industrialised country. There is therefore a need to devise a technique capable of assessing the financial implications of a switch from surface to underground production of aggregates in any region. This paper reports the development of a computerised simulation programme, able to calculate the costs of underground working with sufficient accuracy to facilitate strategic decisions on the merits of more detailed analysis in any area of interest. An example is reported of the use of the programme to evaluate underground stone mining potential in the South East of England. 相似文献
30.
Amina Amine-Khodja Claire Richard Bernadette Lavédrine Ghislain Guyot Olga Trubetskaya Oleg Trubetskoj 《Environmental Chemistry Letters》2006,4(4):249-177
Composts fractions were extracted by water from composts at the beginning and at the end of the composting process. These water extracts were characterized by elementary analysis and spectroscopies, and then, tested for their capacity to photosensitize the degradation of three aromatic compounds: Irgarol, fenuron, and 2,4,6-trimethylphenol. In solar light, the water extracts (25 mg/l) were found to completely degrade 2,4,6-trimethylphenol after 24 h, and afford a transformation of fenuron and Irgarol of 25% and 18%, respectively.An erratum to this article can be found at 相似文献