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Ecological Benefits of the Conservation Reserve Program 总被引:8,自引:0,他引:8
Christopher P. Dunn Forest Stearns Glenn R. Guntenspergen David M. Sharpe 《Conservation biology》1993,7(1):132-139
The Conservation Reserve Program was initiated in 1985 to reduce soil loss on highly erodible agricultural land. This stated objective of the program has been quite successful. However, there are other unintentional yet significant ecological benefits to the program that merit evaluation. These benefits include the reversal of landscape fragmentation, maintenance of regional biodiversity, creation of wildlife habitat, and favorable changes in regional carbon flux. These and other benefits should be used by policy makers and federal officials to maintain the program even after enrollment expectations have been achieved. 相似文献
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Christopher E. Miller 《Journal of Environmental Planning and Management》1993,36(2):149-166
The controversy surrounding planning approval for certain developments associated with a proposal to generate electricity from gas produced at a large coke works is examined. Although the case begins as another conflict in the ‘planning versus pollution control jurisdiction’ tradition, these concerns are eventually superseded by the wider implications for planning of a residents group's attempt to advance its campaign against this long‐standing ‘bad neighbour’ by citing the principle of the ‘direct effect’ of a European Community directive on industrial air pollution. 相似文献
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Christopher Stobart 《Natural resources forum》1991,15(1):41-49
Investment in increased capacity of the major metal producers is examined in the light of changing metal prices and the business cycle. Historically, as metal prices rise, the producers have invested in new mine capacity. This process results in increased production which often comes on stream just as the business cycle is beginning to wane. During the present business cycle the investment pattern of the major mining companies appears to have broken with this historical pattern in that investment strategies are less directed toward increasing capacity. 相似文献
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Summary The ideal dominance distribution model predicts that competition between individuals of a species for territories will result in socially dominant individuals acquiring territories in higher quality habitat than their subordinates. Although the dispersion and relative reproductive success of male red-winged blackbirds (Agelaius phoeniceus) across habitats in eastern Ontario appears to conform to the ideal dominance distribution model, data from a study of three captive groups comprised of males from both high (marsh) and low (upland field) quality habitats failed to support the prediction that males from marsh habitat are dominant to those from upland habitat. Contrary to the prediction males from uplands were generally dominant to males from marshes. We found a significant positive correlation between dominance and both increased epaulet size and increased body size. Controlling for these positive effects, upland males remained generally dominant to marsh males. Measurements of independent samples of males from both habitats indicated that the overall distribution of males does not conform to ideal dominance. We suggest that the strong between-year territory fidelity shown by male red-winged blackbirds and chance events when they initially acquire territories may contribute to this lack of conformity. 相似文献
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In the Imperial County, California, earthquake of 15th October 1979, the Imperial County Services Building was seriously damaged — and has subsequently been demolished. At the time of the earthquake there were approximately 123 occupants in the six-storey reinforced concrete building which housed a number of county service departments. This paper investigates occupant behavior in a building subjected to an earthquake, and describes, in detail, what people do during and immediately subsequent to the shock. 相似文献
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Jonathan Kazmierski Megan Kram Elizabeth Mills David Phemister Nicholas Reo Christopher Riggs 《Journal of Environmental Planning and Management》2004,47(5):709-736
This paper illustrates a landscape ecology approach for land trusts undertaking conservation at the watershed scale. A conservation plan was created for the Grand Traverse Regional Land Conservancy (GTRLC) in the headwaters of Michigan's Manistee River Watershed (USA). Eight conservation drivers were devised to identify Conservation Focus Areas (CFAs) of highest ecological importance. The CFAs were ranked based on ecological importance, feasibility of protection and size. Parcels were ranked, totalling nearly 5000 ha, within the three highest-ranking CFAs in one key county. This approach is useful to land trusts trying to operationalize three distinct goals in conservation planning: to find areas of high ecological importance, to promote the landscape's spatial integrity and to delineate threats to ecological systems and processes. 相似文献