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991.
Opencast coalmining has been undertaken in Britain since 1942, but national policy towards its role in the energy market has fluctuated, and today there is a growing awareness of its detrimental impact on the environment. This paper explores the changing policy background since 1974 and, through an examination of recent planning appeal decisions, assesses the weight placed on the competing factors underlying the present formulation of government policy. It is submitted that at present government has failed to formulate a coherent policy in terms of land‐use and that the cost of this failure is a continued erosion of the environment. 相似文献
992.
Martin H. David Erhard F. Joeres Eric D. Loucks Kenneth W. Potter Stuart S. Rosenthal 《Journal of the American Water Resources Association》1988,24(1):141-148
ABSTRACT: Water level fluctuations of the Great Lakes often have created regional controversies among the states and Canadian provinces that share this vast resource. Even though the 100-year range of their water levels is only four to five feet, episodes of high and low Great Lakes water levels have been a recurring problem throughout the twentieth century. The possibility of increased diversion and consumptive use has exacerbated the existing conflicts over how to manage this water resource. A research project evaluated the effects of interbasin diversion on the Great Lakes system and on the industries that depend on the maintenance of historical water levels, namely hydropower and commercial navigation. The simulation approach employed in this research and some of the important findings are presented. The approach is similar to that used in recent government studies of Great Lakes water level regulation. Several significant modifications were made specifically addressing the diversion issue. Aggregate annual impacts to hydropower and shipping resulting from a diversion of 10,000 cubic feet per second were found to vary from 60 to 100 million dollars. Increases in impacts as a function of diversion rate are nonlinear for the navigation industry. 相似文献
993.
M. van der Zee J. H. Stoutjesdijk P. A. A. W. van der Heijden D. de Wit 《Journal of Polymers and the Environment》1995,3(4):235-242
The biodegradability of oxidized starch and inulin has been studied in relation to the degree of periodate oxidation to dialdehyde derivatives, by measuring oxygen consumption and mineralization to carbon dioxide. A higher degree of oxidation of dialdehyde starch and dialdchyde inulin results in a lower rate at which the polymers are biodegraded. It is demonstrated that the biodegradation rate of dialdehyde inulin derivatives decreases more than that of equivalent starch derivatives. The differences in biodegradation behavior between dialdehyde starch and dialdehyde inulin, resulting from comparable modifications, are discussed in terms of conformational structure. 相似文献
994.
Twenty-five years of HAZOPs 总被引:7,自引:0,他引:7
The HAZOP or hazard and operability study was developed by ICI over 25 years ago and is in wide use today throughout the world. The technique is intended to review, in a formalized manner, the design of a system such as a chemical process production plant to detect potential problems in the operation of the system. The system has been extended for use on all types of production, storage and distribution units. Experience in the use of hazard studies has lead to the development of a phased approach with three distinct design phases. 相似文献
995.
Large-scale constructed wetlands for nutrient removal from stormwater runoff: An everglades restoration project 总被引:14,自引:0,他引:14
Mariano Guardo Larry Fink Thomas D. Fontaine Susan Newman Michael Chimney Ronald Bearzotti Gary Goforth 《Environmental management》1995,19(6):879-889
The South Florida Water Management District (SFWMD) constructed a wetland south of Lake Okeechobee to begin the process of
removing nutrients (especially phosphorus) from agricultural stormwater runoff entering the Everglades. The project, called
the Everglades Nutrient Removal (ENR) project, is a prototype for larger, similarly constructed wetlands that the SFWMD will
build as part of the Everglades restoration program. This innovative project is believed to be one of the largest agricultural
stormwater cleanup projects in the United States, if not in the world. This publication describes the ENR project's design,
construction, and proposed operation, as well as the proposed research program to be implemented over the next few years. 相似文献
996.
The Clean Air Act Amendments of 1977 designated national parks and wilderness areas larger than 1894 ha to be class I areas
for air quality management, setting more restrictive criteria than the National Ambient Air Quality Standards. Class I areas
are afforded the greatest degree of air quality protection under the Clear Air Act of 1970. In recent years, several studies
have documented air pollution effects in the Great Smoky Mountains National Park (GSMNP), the second-largest class I area
in the eastern United States. Air pollution problems of greatest concern in the GSMNP are effects of acid deposition, visibility
impairment, and tropospheric ozone. Several recent events have increased concerns about air quality management in the class
I area of the GSMNP. A forum, sponsored by the Southern Appalachian Man and the Biosphere Cooperative (SAMAB), was held in
March 1992, which involved representative. parties-at-interest and began to address strategies for better management of air
resources in the Southern Appalachians. This paper summarizes those discussions and recommendations and reports actions occurring
as a result of the forum. Another objective of this paper is to present a conceptual framework for more effective management
of the class I area of the GSMNP. 相似文献
997.
A resource survey and planning method for parks, reserves, and other environmentally significant areas (ESAs) is presented in the context of a holistic balanced approach to land use and environmental management. This method provides a framework for the acquisition, analysis, presentation, and application of diverse ecological data pertinent to land use planning and resource management within ESAs. Through the independent analysis and subsequent integration of abiotic, biotic, and cultural or ABC information, land areas within an ESA are identified in terms of their relative environmental significance and environmental constraints. The former term encompasses wildlife, historic, and other resource values, while the latter term reflects biophysical hazards and sensitivities, and land use conflicts. The method thus calls for a matching of an ESA's distinctive attributes with appropriate land use and institutional arrancements through an analysis of available acts, regulations, agencies, and other conservation and land use management mechanisms. The method culminates with a management proposal showing proposed park or reserve allocations, buffer areas, or other land use controls aimed at preserving an ESA's special ecological qualities, while providing for resource development. The authors suggest that all resource management decisions affecting ESA's should be governed by a philosophical stance that recognizes a spectrum of broad land use types, ranging from preservation to extractive use and rehabilitation. 相似文献
998.
999.
W. L. Nutter T. Tkacs P. B. Bush D. G. Neary 《Journal of the American Water Resources Association》1984,20(6):851-858
The breakpoint rainfall hydrology and pesticide options of the field scale model CREAMS (Chemicals, Runoff, and Erosion from Agricultural Management Systems) were used to predict average concentrations of hexazinone [3 cyclohexyl-6-(dimethyl-amino)-1-methyl-1,3,5-triazine-2,4(1H,3H)-dione] in stormflow from four forested watersheds in the upper Piedmont region of Georgia. Predicted concentrations were compared with measured concentrations recorded over a 13-month period. CREAMS accurately predicted hexazinone concetrations in the initial stormflow events which also contained the highest concentrations. The model underestimated the hexazinone concentrations in stormflow two months and greater following pesticide application. In a companion study, the daily rainfall option of the CREAMS model was used to evaluate the reltive risk associated with the maximum expected concentration of hexazinone, bromacil (5-bromo-3 sec-butyl-6 methyuracil), picloram (4-amino-3,5,6 trichloropicolinic acid), dicamba (3,6-dichloro-0-anisic acid), and triclopyr {[(3,5,6-trichloro-2-pyridinyl)oxy] acetic acid} in stormflow from small forested watersheds. The model predicted the following order of potential residue appearance in stormflow: bromacil>triclopyr>hexazinone>picloram>dicamba. Subsurface movement of residues via interflow and deep leaching losses are not simulated by the version of CREAMS used in these studies. 相似文献
1000.
E. D. BROWN 《Natural resources forum》1983,7(1):55-70
In July 1982 the US Government announced that it would not sign the new Convention on the Law of the Sea adopted at the eleventh session of the Third United Nations Conference on the Law of the Sea in April 1982. This article investigates the possible consequences of the failure to achieve a consensus between the Group of 77 and the western industrialised States on a regime to govern the deep-sea mining of manganese nodules. After considering the range of possible outcomes, the author identifies the benefits and costs involved in operating under the two alternative regimes, that provided by the new Convention and related Conference resolutions and the alternative Reciprocating States Regime based on unilateral legislation co-ordinated by a Mini-Treaty. En juillet 1982, le gouvernement des Etats-Unis a annoncé qu'il ne signerait pas la nouvelle Convention sur le droit de la mer qui a été adoptée à la llème session de la troisième Conférence des Nations Unies sur le droit de la mer en avril 1982. Cet article étudie les conséquences possibles de l'absence d'un consensus entre le Groupe des 77 et les nations industrielles occidentales sur un régime devant gouverner l'exploitation des nodules de manganèse que l'on trouve sur les fonds marins profonds. Après avoir consideéré tout un éventail de résultantes éventuelles, l'auteur dresse un état des avantages et désavantages que présentent les deux régimes possibles, c'est-à-dire le régime prévu par la nouvelle Convention et les résolutions concomitantes adoptées par la Conférence et le régime de réciprocité entre états basé sur une législation unilatérale et sanctionné par un mini-traité. En julio de 1982 el gobierno de los Estados Unidos anunció que no firmaría la nueva Convención sobre el Derecho del Maradoptada en la undécima sesión de la Tercera Conferencia de las Naciones Unidas sobre el Derecho del Mar en abril de 1982. Este artículo investiga las posibles consecuencias de la falta de consenso entre el Grupo de los 77 y los estados industriales occidentales sobre el régimen que gobierna la extracción de nódulos de manganeso en mares profundos. Después de considerar el posible rango de consecuencias el autor evalúa los costos y beneficios resultantes de operar bajo dos regímenes alternativos, aquel definido por la nueva convención y las resoluciones relacionadas y el Régimen de Reciprocidad entre Estados basado en legislación unilateral coordinados por el Mini-Tratado. 相似文献