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481.
Silvia H. Bonilla Cecília M.V.B. Almeida Biagio F. Giannetti Donald Huisingh 《Journal of Cleaner Production》2010,18(1):1-5
This issue of the Journal of Cleaner Production is based upon papers presented at the 1st International Workshop Advances in Cleaner Production (CP) held in São Paulo, Brazil, in 2007. The conference had the short-term purpose of deepening the Brazilian discussion on “The Roles of Cleaner Production in the Sustainable Development of Modern Societies”, and it had the long-term objective of providing an on-going interdisciplinary forum for knowledge development and exchange on Cleaner Production (CP) and Sustainable Development. This issue is devoted to papers covering a broad range of perspectives of CP practices and strategies. A special focus is placed upon methodological tools designed to support effective decision-making pertaining to quantitative benefits from CP.The ten papers provide insights from research designed to holistically integrate CP to help society make effective progress to sustainability. Papers cover the importance of informal knowledge, as complementary to formal knowledge, in performing effective ‘Environmental Impact Assessments.’ One paper explores the roles of radical and incremental innovation in the context of alternative automotive technologies. Benefits of Ecodesign are explored in two papers; one concerning its integration with remanufacturing to extend the life of used products and one focusing the adoption of ‘Emergy Environmental Accounting,’ as a complementary decision-making tool. The development of the Brazilian LCI database for ‘hydroelectric power generation’ and its contribution to support regionally relevant LCA studies is highlighted in one paper. The complete production chains of biodiesel and bioethanol are evaluated by using global methodologies, which help in the development of more objective and effective solutions. A “compensatory area”, calculated in terms of emergy, is proposed in order to work in a sustainable way for bamboo production. Finally, a paper about a novel approach for recycling used PET is also included. 相似文献
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484.
Donald W. Watts Jeffrey M. Novak 《Journal of environmental science and health. Part. B》2013,48(5):659-671
Abstract False positive responses on an atrazine (6‐chloro‐N‐ethyl‐N'‐(l‐methylethyl)‐1, 3, 5‐triazine‐2, 4‐diamine) immunoassay kit were investigated to explain possible causes for these occurences. Ground water samples were evaluated with the immunoassay kit and positive responses (>0.20 μg L‐1) were confirmed using gas chromatography/mass spectrometry (GC/MS). Non‐confirming samples (false positives) were analyzed for seven additional compounds on GC. Resulting GC/MS and GC analyses showed that 70% of the false positives could be attributed to two compounds. Prometon (6‐methoxy‐N,N'‐bis(l‐methylethyl)‐1, 3, 5‐triazine‐2, 4‐diamine) was responsible for the majority (64%) of the false positive responses The atrazine metabolite, deethylatrazine (2‐chloro‐4‐amino‐6‐isopropylamino‐1, 3, 5‐triazine), was responsible for the other 6% of the false positives measured. Unattributed false positives (30%) were probably due to an overestimation of pesticide concentrations in the kit's lower detection range. 相似文献
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Scott E Atkinson Donald H Lewis 《Journal of Environmental Economics and Management》1974,1(3):237-250
A number of linear programming models purport to minimize the costs of emission control to achieve ambient air quality standards. Many of the simulations incorporate the simplifying assumption that improvements in ambient air quality are proportional to reductions in regional emissions. This approach minimizes the cost of mass emission reduction, but not the cost to achieve a prescribed ambient air quality. The costs of this emissions least-cost strategy are compared to an ambient least-cost strategy which does achieve prescribed ambient air quality at minimum cost. The cost saving achieved by this strategy relative to the emissions least-cost strategy is as much as 50670. In addition, both are compared to a strategy typical of those currently used by the states, which is found to be as much as ten times as expensive as the ambient least-cost strategy. 相似文献
488.
Directional selection by fisheries and the timing of sockeye salmon (Oncorhynchus nerka) migrations.
Thomas P Quinn Sayre Hodgson Lucy Flynn Ray Hilborn Donald E Rogers 《Ecological applications》2007,17(3):731-739
The timing of migration from feeding to breeding areas is a critical link between the growth and survival of adult animals, their reproduction, and the fitness of their progeny. Commercial fisheries often catch a large fraction of the migrants (e.g., salmon), and exploitation rates can vary systematically over the fishing season. We examined daily records of sockeye salmon (Oncorhynchus nerka) in the Egegik and Ugashik management districts in Bristol Bay, Alaska (USA), for evidence of such temporally selective fishing. In recent years, the early migrants have experienced lower fishing rates than later migrants, especially in the Egegik district, and the median migration date of the fish escaping the fisheries has been getting progressively earlier in both districts. Moreover, the overall runs (catch and escapement) in the Egegik district and, to a lesser extent the Ugashik district, have been getting earlier, as predicted in response to the selection on timing. The trends in timing were not correlated with sea surface temperature in the region of the North Pacific Ocean where the salmon tend to concentrate, but the trends in the two districts were correlated with each other, indicating that there may be some common environmental influence in addition to the effect of selection. Despite the selection, both groups of salmon have remained productive. We hypothesize that this resilience may result from representation of all component populations among the early and late migrants, so that the fisheries have not eliminated entire populations, and from density-dependent processes that may have helped maintain the productivity of these salmon populations. 相似文献
489.
Richard T. Kazmaier Eric C. Hellgren ‡ Donald C. Ruthven III † David R. Synatzske† 《Conservation biology》2001,15(4):1091-1101
Abstract: Considerable effort has been exerted in attempts to understand the complex ecological effects of grazing. North American tortoises, by virtue of their distribution, provide a good model taxon through which to study how grazing effects vary with grazing regime, habitat, and climate. We studied the Texas tortoise ( Gopherus berlandieri ) , which is restricted primarily to privately owned rangelands of southern Texas and northeastern Mexico. Management of this species is hampered by a lack of information on the effects of common land-use practices. We evaluated the effects of moderate grazing by cattle (short-duration, winter-spring rotational grazing regime; 6–28 animal-unit days/ha/year) on this tortoise by comparing two grazed and two ungrazed sites in the Western Rio Grande Plains, Texas ( U.S.A.), from April 1994 to October 1997. We made 132 captures of 106 individuals in the ungrazed pastures and 324 captures of 237 individuals in the grazed pastures. We also radiotracked 22 tortoises in the ungrazed pastures and 25 tortoises in the grazed pastures. Comparisons of relative abundance, body-size distribution, age distribution, body mass, sex ratio, adult survival, proportion of juveniles, and growth rates revealed no differences ( p > 0.05 for all parameters) between tortoises on grazed and ungrazed areas. Based on these results, we suggest that moderate grazing by cattle is not incompatible with maintenance of Texas tortoise populations. Our data were consistent with a general model of tortoise biogeography and tolerance of disturbance which suggests that Texas tortoises are tolerant to intermediate levels of disturbance. Generalities about the effect of cattle grazing on the four North American tortoises should be avoided unless they can be placed in the context of grazing regime, precipitation, habitat quality, and tortoise requirements. 相似文献
490.
L. Donald Duke Molly M. Kihara 《Journal of the American Water Resources Association》1998,34(3):661-676
ABSTRACT: Nonstorm water discharges to municipal separate storm sewer systems (MS4s) are notable for spatial and temporal variability in volume, pollutant type, pollutant concentration, and activity of origin. The objective of this paper was to determine whether current technical knowledge and existing U.S. policy support an improved regulatory approach. The proposed policy would use type of discharge as a regulatory basis, merging the concepts of allowability of de minimis discharges and type-based statewide consistent rules. Specific research objectives were to comprehensively identify discharge types, characterize their prevalence in California, analyze relevant local and regional regulatory guidelines, and systematically evaluate opinions of experts about potential water quality impacts. Results demonstrate nonstorm water discharges were widespread in at least one sector, industrial facilities subject to a state permit; one discharge for every four facilities was reported in 1995, even though the permit explicitly prohibits such discharges. Clear consensus exists for minimal water quality concern for some discharge types when considering both municipal guidelines and experts’ opinions. In particular, condensate from a wide range of equipment and discharges from fire fighting equipment testing were found to be of low concern. Discharge types with consensus high concern were largely limited to discharges prohibited under other regulations, such as wastewater and hazardous waste management controls. Some discharge types where no consensus was identified, such as landscape irrigation, nevertheless generated concern for water quality impacts and appear to be relatively widespread. Available information supports technical feasibility of the proposed policy because at least some discharge types show strong consensus for de minimis impacts among regulatory guidelines and opinions of technical experts. 相似文献