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Reviews of each nation's annual greenhouse gas inventory submissions including forestland are part of the ongoing reporting process of the United Nations Framework Convention on Climate Change. Goals of these reviews include improving quality and consistency within and among reports. One method of facilitating comparisons is the use of a standard index such as an implied emission factor (IEF), which for forest biomass indicates net rate of carbon emission or sequestration per area. Guidance on the use of IEFs in reviews is limited, but there is an expectation that values should be relatively constant both over time and across spatial scales. To address this hypothesis, we examine IEFs over time, derived from U.S. forests at plot-, state-, and national-levels. Results show that at increasingly aggregated levels, relative heterogeneity decreases but can still be substantial. A net increase in U.S. whole-forest IEFs over time is consistent with results from temperate forests of nations in the European Community. IEFs are better viewed as a distribution of values rather than one constant value principally because of sensitivities to productivity, disturbance, and land use change, which can all vary considerably across a nation's forest land. 相似文献
643.
Maria da Gra?a Madeira Martinho Ana Isabel Silveira Elsa Maria Fernandes Duarte Branco 《Waste management & research》2008,26(5):484-490
This report proposes a new set of guidelines for the characterization of municipal solid waste. It is based on an analysis of reference methodologies, used internationally, and a case study of Valorsul (a company that handles recovery and treatment of solid waste in the North Lisbon Metropolitan Area). In particular, the suggested guidelines present a new definition of the waste to be analysed, change the sampling unit and establish statistical standards for the results obtained. In these new guidelines, the sampling level is the waste collection vehicle and contamination and moisture are taken into consideration. Finally, focus is on the quality of the resulting data, which is essential for comparability of data between countries. These new guidelines may also be applicable outside Portugal because the methodology includes, besides municipal mixed waste, separately collected fractions of municipal waste. They are a response to the need for information concerning Portugal (e.g. Eurostat or OECD inquiries) and follow European Union municipal solid waste management policies (e.g. packaging waste recovery and recycling targets and the reduction of biodegradable waste going to landfill). 相似文献
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Chencho Norbu Prof. Timothy J. Downs Edward Yeboah Dr. L.J.R. Scholtens Dr. Jyotsna Bapat Maren Oelbermann Ph.D. Sayyed Ahang Kowsar Jaime Alexandra Webbe Bram Govaerts Ph.D. Nele Verhulst M. Sc. Goodspeed Kopolo Maria Rosário Partidário Mr. N’guessan Alphonse Kouassi John All Ph.D. JD Narcisa Pricope Leslie Lipper 《Natural resources forum》2008,32(3):252-256
646.
Umberto Arena Lucio Zaccariello Maria Laura Mastellone 《Waste management (New York, N.Y.)》2010,30(7):1212-1219
Five alternative waste-derived fuels obtained from municipal solid waste and different post-consumer packaging were fed in a pilot-scale bubbling fluidized bed gasifier, having a maximum feeding capacity of 100 kg/h. The experimental runs utilized beds of natural olivine, quartz sand or dolomite, fluidized by air, and were carried out under various values of equivalence ratio. The process resulted technically feasible with all the materials tested. The olivine, a neo-silicate of Fe and Mg with an olive-green colour, has proven to be a good candidate to act as a bed catalyst for tar removal during gasification of polyolefin plastic wastes. Thanks to its catalytic activity it is possible to obtain very high fractions of hydrogen in the syngas (between 20% and 30%), even using air as the gasifying agent, i.e. in the most favourable economical conditions and with the simplest plant and reactor configuration. The catalytic activity of olivine was instead reduced or completely inhibited when waste-derived fuels from municipal solid wastes and aggregates of different post-consumer plastic packagings were fed. Anyhow, these materials have given acceptable performance, yielding a syngas of sufficient quality for energy applications after an adequate downstream cleaning. 相似文献
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Type A behavior dimensions and optimism were examined as predictors of health and performance. In addition, this research also explored the ways that Type As and optimists cope with stressful situations. The achievement striving dimension of the Type A behavior pattern and optimism were positively related to class performance, while the anger/hostility dimension was positively related to the health symptom of anxiety. Optimism, on the other hand, was negatively related to anxiety. The interaction of achievement striving and optimism was negatively related to anxiety. Additionally, while achievement striving was positively related to problem-focused coping, irritability showed a negative association with problem-focused coping strategy. The results of this study provide insights for both individuals and organizations regarding how to cope with daily stresses in order to lower health risks and improve performance. 相似文献
649.
George R. Holdren Jr. Timothy C. Strickland Bernard J. Cosby David Marmorek David Bernard Robert Santore Charles T. Driscoll Linda Pardo Carolyn Hunsaker Robert S. Turner John Aber 《Environmental management》1993,17(3):355-363
The critical loads approach is emerging as an attractive means for evaluating the effects of atmospheric deposition on sensitive
terrestrial and aquatic ecosystems. Various approaches are available for modeling ecosystem responses to deposition and for
estimating critical load values. These approaches include empirical and statistical relationships, steady-state and simple
process models, and integrated-effects models. For any given ecosystem, the most technically sophisticated approach will not
necessarily be the most appropriate for all applications; identification of the most useful approach depends upon the degree
of accuracy needed and upon data and computational requirements, biogeochemical processes being modeled, approaches used for
representing model results on regional bases, and desired degree of spatial and temporal resolution. Different approaches
are characterized by different levels of uncertainty. If the limitations of individual approaches are known, the user can
determine whether an approach provides a reasonable basis for decision making. Several options, including point maps, grid
maps, and ecoregional maps, are available for presenting model results in a regional context. These are discussed using hypothetical
examples for choosing populations and damage limits.
The research described in this article has been funded by the US Environmental Protection Agency. This document has been prepared
at the EPA Environmental Research Laboratory in Corvallis, Oregon, through contract #68-C8-0006 with ManTech Environmental
Technology, Inc., and Interagency Agreement #1824-B014-A7 with the U.S. Department of Energy and at Oak Ridge National Laboratory
managed by Martin Marietta Energy Systems, Inc., under Contract DE-AC05-84OR21400 with the US Department of Energy. Environmental
Sciences Division Publication No. 3904. It has been subjected to the agency’s peer and administrative review and approved
for publication. Mention of trade names or commercial products does not constitute endorsement or recommendation for use. 相似文献
650.
Creating an effective and consistent corporate health, safety, and environment program for a decentralized, international company poses unique challenges. This article describes how, with global company input, Kodak has established a set of twenty-eight corporate HSE performance standards. Worldwide facility compliance with these standards is monitored through Kodak's Corporate HSE Assessment Program and through the Corporate Self-Appraisal Program. 相似文献