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351.
John R. Ehrenfeld 《环境质量管理》1995,4(4):37-51
For most of its history of environmental protection, U.S. policy has concentrated on a pollution control strategy based on single medium emissions: air, water, or land. Efforts to mitigate environmental impacts to one medium often resulted in greater impacts to others. While much environmental improvement has occurred via this system over the last quarter-century, it is generally recognized that alternative strategies which address environmental impacts across all media in an integrated manner will be necessary for continued improvement. Increasingly, regulatory strategies that result in only passive compliance will be insufficient to meet these demands. This article demonstrates why new strategies which encourage proactive behavior are necessary. A new framework for making strategic decisions—design for environment—concerning the relation between our actions and environment is necessary to ensure a sustainable future. 相似文献
352.
353.
The siting of facilities with undesirable environmental characteristics often leads to public conflict. Efforts to resolve the conflict and make siting decisions frequently exacerbate the problem. Environmental mediation, the process of negotiating an agreeable settlement, is an accepted approach to resolving conflict. This paper explores the use of incentive systems as a means of achieving equity in environmental mediation. Obnoxious and noxious characteristics of facilities are discussed as the basis of conflicts. Four types of incentives—mitigation, compensation, reward, and participation—are discussed. The paper concludes with a discussion of the utility and application of incentives for solving environmental conflicts. 相似文献
354.
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356.
Robert B. Leonard Donald C. Signor Donald G. Jorgensen John O. Helgesen 《Journal of the American Water Resources Association》1983,19(6):903-912
ABSTRACT: The Dakota aquifer, composed of the Dakota Sandstone and stratigraphically equivalent sandstone units of Cretaceous age, is the upper-most regional aquifer underlying the extensively developed High Plains aquifer of the midwestern United States. The concentration of dissolved solids in ground water of the Dakota aquifer ranges from less than 500 milligrams per liter in calcium bicarbonate type water in the eastern outcrop area to more than 100,000 milligrams per liter in sodium chloride type oilfield brine in the Denver Basin to the west. Preliminary maps showing the distribution of dissolved solids confirm the complex nature of the Dakota aquifer as inferred from stratigraphic and hydraulic evidence. Extensive vertical leakage through confining layers, local recharge at the truncated eastern boundary, and a barrier to recharge along the western edge of the Denver Basin are consistent with the distribution of hydraulic head and dissolved solids. 相似文献
357.
John C. Peters 《Journal of the American Water Resources Association》1983,19(6):913-920
ABSTRACT: The routing of flood waves through the Central Basin of the Passaic River in New Jersey is complex because of flat gradients and flow reversals. The one-dimensional unsteady flow program DWOPER, developed by the National Weather Service, was used to simulate flood wave movement through the Basin. A historical event was used for calibration and two synthetic events were simulated. Boundary conditions consisted of discharge hydrographs at inflow points to the study area, local flow hydrographs at interior points, and a stage discharge relation for flow over the crest of a diversion dam at the basin outlet. Manning's n values were adjusted based on stage and discharge data for the historical event; however, verification data were not available for events comparable in magnitude to the synthetic events. Aspects of the investigation reported include techniques for characterizing the flow system, model calibration, techniques for representing a tunnel diversion, and simulation results. 相似文献
358.
Under the United States Clean Air Act Amendments of 1977, a class I designation safeguards wilderness areas from the negative
effects of new sources of air pollution. We monitored streamwater chemistry in the class I Lye Brook Wilderness in southwestern
Vermont from May 1994 through August 1995. Stream samples were collected biweekly at nine sampling locations throughout the
wilderness and were analyzed for major cations and anions, dissolved organic carbon, pH, and acid-neutralizing capacity. Eight
of nine sites sampled had mean annual acid neutralizing capacity values below zero. During the study period, decreases in
streamwater acid neutralizing capacity values were caused primarily by SO4
2−. At some sites, however, NO3
− and naturally occurring, weak organic acids were seasonally important. During high discharge, the low pH and high concentrations
of inorganic monomeric Al were at levels that are toxic to acid-sensitive aquatic species. Watershed mass balances were calculated
to determine annual gains or losses for measured ions. These budgets indicate that S inputs and outputs were nearly equal,
there was a net loss of base cations, and a net gain in N. How long these watersheds can continue to assimilate additional
N inputs is unknown. 相似文献
359.
John F. Potter 《The Environmentalist》2002,22(4):395-395
Call for Papers
Rolex Calls for Entries to 11th Awards for Enterprise and Extends Deadlines for All Countries 相似文献360.