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621.
Suppressant foams used to fight forest fires may leave residual effects on surviving biota that managers need to consider prior to using them. We examined how three fire-suppressant foams (FSFs) (Forexpan S, Phos-Chek-WD881, and Silv-ex) affected seed germination and physiological responses of three plant species. Exposure to FSFs, whether in diluted concentrations or those typical in the field, reduced final germination percentages of seeds grown in petri dishes and within growth chambers. However, the FSFs did not cause total germination failure in any treatment. Inhibition of germination increased with longer exposure times, but only to diluted FSF solutions. Unlike in the laboratory experiments, none of the three FSFs affected seedling emergence when tested in field conditions. Further, we found no evidence of long-term phytotoxic effects on antioxidant enzyme activity nor chlorophyll content of the plant saplings. Therefore, although the three FSFs showed evidence of phytotoxicity to plants in laboratory tests, their actual impact on terrestrial ecosystems may be minimal. We suggest that the benefits of using these FSFs to protect plants in threatened forest ecosystems outweigh their minor risks. 相似文献
622.
Aoife Donnelly Owen Naughton Brian Broderick Bruce Misstear 《Environmental Modeling and Assessment》2017,22(3):231-241
A novel hybrid model has been developed to support the provision of real-time air quality forecasts. Statistical techniques have been applied in parallel with air mass history modelling to provide an efficient and accurate forecasting system with the ability to identify high NO2 events, which tend to be the episodes of most significance in Ireland. Air mass history modelling and k-means clustering are used to identify air mass types that lead to high NO2 levels in Ireland. Trajectory matching techniques allow data associated with these air masses to be partitioned during model development. Non-parametric regression (NPR) has been applied to describe nonlinear variations in concentration levels with wind speed, direction and season and produce a set of linearized factors which, together with other meteorological variables, are employed as inputs to a multiple linear regression. The model uses an innovative integrated approach to combine the NPR with the air mass history modelling results. On validation, a correlation coefficient of 0.75 was obtained, and 91 % of daily maximum (hourly averaged) NO2 predictions were within a factor of two of the measured value. High pollution events were well captured, as indicated by strong agreement between measured and modelled high percentile values. The model requires only simple input data, does not require an emission inventory and utilises very low computational resources. It represents an accurate and efficient means of producing real-time air quality forecasts and, when used in combination with forecaster experience, is a useful tool for identifying periods of poor air quality 24 h in advance. The hybrid approach outlined in this paper can easily be applied to produce high-quality forecasts of both NO2 and additional pollutants at new locations/countries where historical monitoring data are available. 相似文献
623.
Francesca Matthews Pillemer Robert J. Blendon Alan M. Zaslavsky Bruce Y. Lee 《Disasters》2015,39(1):125-145
Non‐pharmaceutical interventions (NPIs) are an important public health tool for responding to infectious disease outbreaks, including pandemics. However, little is known about the individual characteristics associated with support for NPIs, or whether they are consistent across regions. This study draws on survey data from four regions—Hong Kong, Singapore, Taiwan, and the United States—collected following the Severe Acute Respiratory Syndrome (SARS) outbreak of 2002–03, and employs regression techniques to estimate predictors of NPI support. It finds that characteristics associated with NPI support vary widely by region, possibly because of cultural variation and prior experience, and that minority groups tend to be less supportive of NPIs when arrest is the consequence of noncompliance. Prior experience of face‐mask usage also results in increased support for future usage, as well as other NPIs. Policymakers should be attentive to local preferences and to the application of compulsory interventions. It is speculated here that some public health interventions may serve as ‘gateway’ exposures to future public health interventions. 相似文献
624.
Bruce Christopher Glavovic 《Regional Environmental Change》2016,16(2):353-365
Coastal sustainability is elusive in South Africa and the Mississippi delta. These case studies and convergent literatures demonstrate the merits of reconceptualising coastal management as a transformative practice of deliberative governance. A normative framework is presented that focuses attention on underpinning deliberative outcomes to enable governance actors and networks to build cognitive, democratic, sociopolitical and institutional capacity to transform unsustainable and maladaptive coastal practices. But operationalising such intentions is complex and contested and requires a volte-face in thinking and practice. The South African and Mississippi delta experiences provide insights about how to develop a deliberative praxis of coastal governance based on consideration of the choice of process, timeliness, quality of process, equity and representation, connections to the policy cycle, impact, implementation and institutionalisation. 相似文献
625.
Davlasheridze Meri Atoba Kayode O. Brody Samuel Highfield Wesley Merrell William Ebersole Bruce Purdue Adam Gilmer Robert W. 《Mitigation and Adaptation Strategies for Global Change》2019,24(3):329-354
Mitigation and Adaptation Strategies for Global Change - Rapid population growth, urbanization, and concentration of valuable assets and strategic infrastructure in coastal regions make coastal... 相似文献
626.
Leakage and Comparative Advantage Implications of Agricultural Participation in Greenhouse Gas Emission Mitigation 总被引:2,自引:0,他引:2
Heng-Chi Lee Bruce A. McCarl Uwe A. Schneider Chi-Chung Chen 《Mitigation and Adaptation Strategies for Global Change》2007,12(4):471-494
The world is moving toward efforts to reduce net greenhouse gas emissions. Reduction efforts may involve the agricultural
sector through options such as planting of trees, altering crop and livestock management, and increasing production of biofuels.
However, such options can be competitive with domestic food production. In a free trade arena, reduced domestic food production
could stimulate increased production and exports in other countries, which are not pursuing net emission reductions. As a
consequence, emission reduction efforts in implementing countries may be offset by production increases stimulated in other
countries.
We examine the competitive effects of agriculturally related emission reduction actions on agricultural production and international
trade. In doing this, we employ the assumption that U.S. emission reduction caused cost increases will also occur in other
reducing countries. We consider emission reduction: 1) unilaterally by the U.S., 2) by all Kyoto Protocol Annex B countries,
and 3) globally. The results, which are only suggestive of the types of effects that would be observed due to the simplifying
cost assumptions, indicate compliance causes supply cutbacks in regulated countries and increases in non-regulated countries.
The study results show that producers in regulating countries are likely to benefit and consumers lose due to commodity price
increases.
Seniority of Authorship is shared among the first three authors. 相似文献
627.
Bruce A. Ramsay Ilie Saracovan Juliana A. Ramsay Robert H. Marchessault 《Journal of Polymers and the Environment》1994,2(1):1-7
A simple method was developed for the preparation of an autoclavable, long-side-chain poly (-hydroxyalkanoate) (LSC-PHA) colloidal suspension, which was used as a substrate for enzymatic degradation and to prepare agar overlay plates for the isolation of microorganisms producing extracellular LSC-PHA depolymerase. Six cultures producing extracellular LSC-PHA depolymerase were isolated from a composted hydrocarbon-contaminated soil. All were pseudomonads or related bacteria. All (with the possible exception ofXanthomonas maltophilia) could produce LSC PHA. Except forX. maltophilia none could hydrolyze poly (-hydroxybutyrate). Screening of sevenPseudomonas strains known to accumulate LSC PHA showed that all were negative for extracellular LSC-PHA depolymerase production. It was concluded that extracellular LSC-PHA depolymerase producers are found mostly in the genusPseudomonas but that they are relatively uncommon. 相似文献
628.
A summary of environmental legislation targeting disposable diapers and review of related literature
Patricia Cox Crews Wendelin Rich Shirley Niemeyer 《Journal of Polymers and the Environment》1994,2(1):39-48
In recent years state and local governments, as well as private citizens, have become very concerned about the mounting solid waste disposal problem facing our nation. Special concern has been expressed over the presence of disposable diapers in the solid waste stream. Responding to the concerns, legislators in at least 25 states proposed actions regarding disposable diapers between 1990 and 1992. Several factors contributed to the number of legislative proposals regarding disposable diapers over the past few years. First was the public's and legislators' misconception about the contribution of disposable diapers to the solid waste stream. Second was an erroneous assumption held by the public and some legislators that biodegradation readily occurs in landfills. Third was the desire to increase demand for agricultural products by requiring the use of degradable products. These contributing factors and other issues surrounding the proposal and passage of environmental legislation pertaining to disposable diapers are presented in this paper and the relevant literature is summarized. To provide the necessary context, the paper contains a review of the literature concerning disposable diapers, their composition and usage; and their environmental impact and fate and a comparison of their performance and cost to those of cloth diapers. 相似文献
629.
630.
We captured two species of deep-sea zoarcids, Melanostigma pammelas and Lycodapus mandibularis, from Monterey Bay California and maintained them in the laboratory. One shallow-water zoarcid, Eucryphycus californicus, and an ecologically and morphologically similar stichaeid fish Xiphister atropurpureus were collected from intertidal and subtidal habitats in Monterey Bay. We investigated the absorption and assimilation efficiencies
of these fishes to determine whether deep-sea species have evolved mechanisms to increase their efficiency of food use. Fishes
were placed in experimental chambers and fed a known quantity of food. Ammonia excretion was measured and feces were collected
daily. Both food and feces were analyzed for water, protein, lipid and ash to determine specific absorption efficiencies.
Absorption ranged from 87.7 to 92.4% and assimilation efficiencies from 84.0 to 86.5%. Meal sizes from 0.5 to 4.0% of body
weight did not affect the results. No significant differences were found between deep-sea and shallow-water species fed single
meals or fed ad libitum for 10 days. This suggests that the selective pressure to maximize absorption and assimilation is
universal and is not affected by the productivity of the habitat occupied. However, the relative size of the intestine in
the deep-sea species was significantly smaller suggesting that they had a lower metabolic cost to maintain their digestive
apparatus. It could not be concluded whether this was the result of pressure to conserve energy or rather the tendency of
the shallow-living species to ingest more refractory material (i.e. sediment, algae). 相似文献