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31.
In 1995 the authors spent a considerable amount of time conducting audits and audit training classes all over the world. In rolling out Colgate-Palmolive's reengineered environmental audit program, they coupled a two-day training program with a three-day audit. Whether in Asia-Pacific, South America, Europe, or the United States, auditors, especially those newly trained, always seemed to fall into the same traps time and again. In order to facilitate the learning process, the authors prepared a list of 20 tips to use at the beginning and end of all training programs and audits. In this article, the authors share the 20 “golden rules” to help all auditors improve the quality of their audits. 相似文献
32.
Treatment of risk in environmental impact assessment 总被引:7,自引:0,他引:7
Glenn W. Suter II Lawrence W. Barnthouse Robert V. O'Neill 《Environmental management》1987,11(3):295-303
Risk assessment and environmental impact assessment have developed as separate traditions. While environmental impact assessment is a broad field that includes all activities that attempt to analyze and evaluate the effects of human and related actions on the environment, risk assessment has been concerned with the relatively well-defined regulatory problems and employs formal quantitative analysis of the probability of specific undesired events, such as cancer. Risk analytic approaches, particularly the explicit treatment of uncertainty, can significantly contribute to environmental assessments. This article discusses the type and sources of uncertainty in environmental assessments, techniques for their quantification, and ways to use uncertainty estimates to calculate probabilities of effects or probabilities of exceeding environmental standards and to determine the need for mitigation or additional research.This article was presented at the International Institute of Applied Systems Analysis, Task Force Meeting on Risk and Policy Analysis under Conditions of Uncertainty, Laxenburg, Austria, November 1985. 相似文献
33.
Stephen J. Lawrence Parker J. Wigington 《Journal of the American Water Resources Association》1987,23(6):1069-1076
ABSTRACT: Oxidized nitrogen (nitrite + nitrate N) concentrations were measured from bulk precipitation, bulk through-fall, and streamflow in a 7.86 hectare forested watershed in southeastern Oklahoma during the wet season from March through June 1983. Oxidized nitrogen inputs comparable to results of other studies were recorded during the 19 rainstorms sampled. Oxidized nitrogen concentrations appeared to increase after rainfall interacted with the pine and hardwood canopies and were inversely related to both rainfall and through-fall depth. Oxidized N concentrations in streamflow were greatest during the rising limb of storm flow with subsequent decreases during the falling limb of storm hydrographs and lowest during base flow. The oxidized N inputs from bulk precipitation were considerably greater than outputs from streamflow resulting in a net retention of oxidized nitrogen within the watershed during the study period. 相似文献
34.
S. Lawrence Dingman 《Journal of the American Water Resources Association》1981,17(4):684-690
: In general, the choice among reservoirs for water supply or flow augmentation is a multiobjective problem. Choices are based in part on the yield available from water supply reservoirs or, in the case of flow augmentation reservoirs, on the increase in low flows at downstream locations. Detailed estimates of these effects may be too costly for basin planning purposes. Thus this paper presents methods for rapid estimation of those quantities for New Hampshire. For water supply reservoirs, a composite empirical relation between Y95 (the draft available 95 percent of the time) and storage ratio, S*, is developed from previous studies in the region. For flow augmentation reservoirs, empirical relations between S* and degree of regulation, R*, are applied to each upstream regulating reservoir. Values of regulation arc then summed and divided by the mean flow at the downstream reach of interest. This parameter, (ΓR)*, is then related to increase in flow available 95 percent of the time by an empirical relation. 相似文献
35.
36.
S. Lawrence Dingman Kevin J. Palaia 《Journal of the American Water Resources Association》1999,35(5):1233-1243
We develop and compare three regression models for estimating flood quantiles at ungaged stream reaches in New Hampshire and Vermont. These models emerge from systematic analysis and validation of relations between flood magnitude and six candidate predictors reflecting basin size, topography, and climate and channel size at 36 gaging stations with record lengths exceeding 20 years. Of the candidate predictors, bank full width is most highly correlated with flood magnitude and the best prediction equation is based on width. Thus channel geometry is closely related to the current hydrologic regime in spite of geologically recent glaciation and apparently non-alluvial bank materials. We also develop models that use information obtainable from maps or GIS. The best of these uses drainage area and drainage-basin elevation as predictors, but it is substantially less precise than the width-based relation. A third relation using only drainage area as a predictor is even less precise but may be useful for some purposes. No other single predictors or combinations yielded useful predictions, although some had been included in previously-established models for the region. Model comparison included examination of residuals generated by regression using one-at-a-time suppression of data points and comparison with precision obtainable with gaging records of varying lengths. 相似文献
37.
Water movement within the unsaturated zone in four agricultural areas of the United States 总被引:2,自引:0,他引:2
Millions of tons of agricultural fertilizer and pesticides are applied annually in the USA. Due to the potential for these chemicals to migrate to groundwater, a study was conducted in 2004 using field data to calculate water budgets, rates of groundwater recharge and times of water travel through the unsaturated zone and to identify factors that influence these phenomena. Precipitation was the only water input at sites in Indiana and Maryland; irrigation accounted for about 80% of total water input at sites in California and Washington. Recharge at the Indiana site (47.5 cm) and at the Maryland site (31.5 cm) were equivalent to 51 and 32%, respectively, of annual precipitation and occurred between growing seasons. Recharge at the California site (42.3 cm) and Washington site (11.9 cm) occurred in response to irrigation events and was about 29 and 13% of total water input, respectively. Average residence time of water in the unsaturated zone, calculated using a piston-flow approach, ranged from less than 1 yr at the Indiana site to more than 8 yr at the Washington site. Results of bromide tracer tests indicate that at three of the four sites, a fraction of the water applied at land surface may have traveled to the water table in less than 1 yr. The timing and intensity of precipitation and irrigation were the dominant factors controlling recharge, suggesting that the time of the year at which chemicals are applied may be important for chemical transport through the unsaturated zone. 相似文献
38.
Morton Corn Ph.D. Lawrence Demaio 《Journal of the Air & Waste Management Association (1995)》2013,63(1):26-30
Atmospheric dustfall was qualitatively examined for sulfate content by the techniques of chemical micrurgy. Quantitative assessment of suspended sulfate particulate according to size was by cascade impactor sampling and turbidimetric analysis of stage washings as BaSO4. Sulfate particles less than 1.9 micron mass median diameter in size contributed approximately 43% by weight and 90% by number to total particulate sulfate in Pittsburgh air. The mechanics of particulate sulfate formation in the atmosphere are discussed on the basis of these findings. 相似文献
39.
Citizen science networks in natural history and the collective validation of biodiversity data 下载免费PDF全文
Biodiversity data are in increasing demand to inform policy and management. A substantial portion of these data is generated in citizen science networks. To ensure the quality of biodiversity data, standards and criteria for validation have been put in place. We used interviews and document analysis from the United Kingdom and The Netherlands to examine how data validation serves as a point of connection between the diverse people and practices in natural history citizen science networks. We found that rather than a unidirectional imposition of standards, validation was performed collectively. Specifically, it was enacted in ongoing circulations of biodiversity records between recorders and validators as they jointly negotiated the biodiversity that was observed and the validity of the records. These collective validation practices contributed to the citizen science character or natural history networks and tied these networks together. However, when biodiversity records were included in biodiversity‐information initiatives on different policy levels and scales, the circulation of records diminished. These initiatives took on a more extractive mode of data use. Validation ceased to be collective with important consequences for the natural history networks involved and citizen science more generally. 相似文献
40.
Assessing ecological risk on a regional scale 总被引:17,自引:0,他引:17
Carolyn T. Hunsaker Robin L. Graham Glenn W. Suter II Robert V. O'Neill Lawrence W. Barnthouse Robert H. Gardner 《Environmental management》1990,14(3):325-332
Society needs a quantitative and systematic way to estimate and compare the impacts of environmental problems that affect
large geographic areas. This paper presents an approach for regional risk assessment that combines regional assessment methods
and landscape ecology theory with an existing framework for ecological risk assessment. Risk assessment evaluates the effects
of an environmental change on a valued natural resource and interprets the significance of those effects in light of the uncertainties
identified in each component of the assessment process. Unique and important issues for regional risk assessment are emphasized;
these include the definition of the disturbance scenario, the assessment boundary definition, and the spatial heterogeneity
of the landscape.
Although the research described in this article has been funded wholly or in part by the United States Environmental Protection
Agency (EPA) through Interagency Agreement Number DW89932112-01-2 to the U.S. Department of Energy, it has not been subjected
to EPA review and therefore does not necessarily reflect the views of EPA and no official endorsement should be inferred. 相似文献