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The unprecedented population growth of recent years and the requisite economic activity to support that growth have heightened public awareness of the resultant environmental challenges we now face. Today it is widely acknowledged that we must change course to assure the same quality of life for future generations as has been experienced by those of the past. These changes in human behavior must occur in individuals, organizations, businesses, communities, and governments. The basis of this change will occur through education and leadership. Many initiatives have evolved to begin this movement toward sustainability, but the higher education sector, which prepares our leaders, has been slow to respond. The founders of one new initiative, BRIDGES, explore what needs to be done to drive this change, what is already being done, and how the BRIDGES program uses partnerships with these existing efforts to create a model of what higher education must offer in order to prepare effective leaders for tomorrow.  相似文献   
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In the framework of dynamic morphology theory, the centers of gravity and geometric centers of projections have been determined for the bodies of more than 182 forms of invertebrates, and these data have been used to distinguish four types of dynamic body shapes. It has been demonstrated that specific dynamic types of body shape are characteristic of individual taxa. In addition, there are a group of “transformers,” which may assume any dynamic type of shape, and a group of invertebrates with one predominant dynamic type.  相似文献   
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Fluxes of dissolved organic matter (DOM) in larch biogeocenoses and its export from the drainage basin have been studied in the zone of continuous permafrost. A comparative assessment of DOM input into the soil has been made on slopes of northern and southern exposures (as variants reflecting the current state and warming). The dynamics of DOM export in a creek depending on the increasing depth of the active soil horizon in the drainage area have been revealed. It is concluded that an increase in the depth of the seasonally thawing layer induced by global warming will not have any significant effect on the amount of annual DOM export. Reduction of DOM export may be expected upon a decrease in litter stocks under the effect of their mineralization and forest fires.  相似文献   
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ABSTRACT: “Nuclear winter,” more properly called “nuclear fall,” could be caused by injection of large amounts of dust into the atmosphere. Besides causing a decrease in temperature, it could be accompanied by “nuclear drought,” a catastrophic decrease in precipitation. Dry land agriculture would then be impossible, and municipal, industrial, and irrigation water supplies would be diminished. It has been argued that nuclear winter/fall poses a much greater threat to human survival than do fall out or the direct impacts of a conflict. However, this does not appear to be true, at least for the U.S. Even under the unprecedented drought that could result from nuclear fall, water supplies would be available for many essential activities. For the most part, ground water supplies would be relatively invulnerable to nuclear drought, and adequate surface supplies would be available for potable uses. This assumes that conveyance facilities and power supplies survive a conflict largely intact or can be repaired.  相似文献   
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