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Coastal wetlands are a valuable resource to North Carolina, USA, representing important habitat for marine organisms and providing flood control areas and buffer zones from marine storms. An analysis of wetland development trends in coastal North Carolina from 1970 to 1984 was conducted using over 3000 files containing 15 years of permitting records. The total amount of coastal wetland area altered due to authorized development under the Coastal Area Management Act (CAMA), the Dredge and Fill Law, and Section 404 of the Federal Water Pollution Control Act is 1740 ha. This represents nearly 2% of the salt marsh wetlands along the coast of North Carolina. The number of permits issued steadily increased during the 1980s; however, the total amount of wetland loss decreased each year. A few large projects in the early 1970s accounted for nearly 70% of all wetland area developed during the 15-year period. Nearly two-thirds of all projects involving wetland destruction involved impacts on high marsh ecosystems. Bulkheads, canals, and filling activities made up 80% of the projects requiring permits; 62% of the permits were issued to private landowners, but this group accounted for only 16% of the losses of wetland area. Utility companies, which accounted for less than 1% of the permits issued, were responsible for 46% of the permitted wetland loss during the 15-year study period. Future studies should address agriculture and forestry practices which are exempt under CAMA laws and therefore their effects on wetland alteration have not been quantified.  相似文献   
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This paper presents the findings of a study commissioned by World Food Programme (WFP) in early 2006 to enhance understanding of how the conflict in Darfur has affected livelihoods and markets, and of the effects of food aid. The livelihoods of many in Darfur were devastated early on in the conflict, principally through the widespread looting or destruction of assets and highly restricted population movements, which struck at the heart of pre-conflict livelihoods. Livelihood strategies for most people are now restricted, poorly remunerated and often associated with high risk of attack. Patterns of coercion and exploitation have also become entrenched; and markets and trade, the lifeblood of Da fur's economy pre-conflict, severely disrupted. Against this backdrop the impact of food aid on livelihoods in Darfur has been overwhelmingly positive. The paper proposes a number of preconditions for investment in recovery in Darfur, and recommends ways in which livelihoods can be supported in the current context of ongoing conflict.  相似文献   
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We examine vigilance within a mixed-species troop of saddleback (Saguinus fuscicollis) and moustached (S. mystax) tamarins over a complete year. Saddleback tamarins were consistently more vigilant than moustached tamarins. This may be linked to their preference for lower strata. In accordance with previous studies of other primates, vigilant tamarins of both species were significantly further away from their nearest neighbours, and were also at lower heights in the forest than non-vigilant individuals. There was no observed sex difference in the amount of time spent vigilant. In terms of modes of scanning, the saddleback tamarins looked up significantly more frequently than the moustached tamarins, whereas there was no difference between the species in the frequency of side sweeps. There were no differences between the sexes in the frequencies of either type of vigilant behaviour. The proportion of time spent vigilant was higher than average immediately prior to entering a sleeping site for saddleback tamarins, but not for moustached tamarins. Both species were more vigilant immediately after exiting a sleeping site than at other times of the day. There was significant variation in the amount of time devoted to vigilance over the course of the year. These findings are discussed with respect to the social structure, ecology and main predator threats facing these species.Communicated by D. Watts  相似文献   
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Regional Environmental Change - The characterization of Pacific Islands as especially vulnerable to climate change often undervalues the cultural resilience of their inhabitants. On many...  相似文献   
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