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灾害是人类面临的最严重的威胁。本文简要列述了各类灾害对国民经济建设和人类生存的危害性,论述了灾害的分类和体系特征,探讨了灾害形成的科学机理,强调了开展多学科、大体系研究的重要意义。同时结合国土环境遥感调查,提出了开展灾害学研究、监测防御、减灾抗祸的对策和建议,以期发挥现代地球科学理论与遥感技术的潜力,为促进灾害学的研究、保障人类更好地生存与发展作出贡献。 相似文献
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可持续发展与自然灾害类型的分析研究 总被引:1,自引:1,他引:1
彭珂珊 《云南地理环境研究》1997,9(1):23-33
在人口与经济快速增长的条件下,人与自然关系的不协调发展导致了自然灾害频繁发生。为了协调环境与资源的关系,拓展并良化人类生存空间,作者根据多年来收集的自然灾害资料与研究成果,对自然灾害的分类与危害进行了系统分析,在采用边缘科学相互交叉的基础上,从社会经济可持续发展的战略角度出发,总结了国内外防灾工作的经验,提出了防御自然灾害的减免措施。 相似文献
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Skin toxins in coral‐associated Gobiodon species (Teleostei: Gobiidae) affect predator preference and prey survival
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Predation risk is high for the many small coral reef fishes, requiring successful sheltering or other predator defence mechanisms. Coral‐dwelling gobies of the genus Gobiodon live in close association with scleractinian corals of the genus Acropora. Earlier studies indicated that the low movement frequency of adult fishes and the development of skin toxins (crinotoxicity) are predation avoidance mechanisms. Although past experiments showed that predators refuse food prepared with goby skin mucus, direct predator–prey interactions have not been studied. The present study compares the toxicity levels of two crinotoxic coral gobies – Gobiodon histrio, representative of a conspicuously coloured species, and Gobiodon sp.3 with cryptic coloration – using a standard bioassay method. The results show that toxin levels of both species differ significantly shortly after mucus release but become similar over time. Predator preferences were tested experimentally in an aquarium in which the two gobies and a juvenile damselfish Chromis viridis were exposed to the small grouper Epinephelus fasciatus. Video‐analysis revealed that although coral gobies are potential prey, E. fasciatus clearly preferred the non‐toxic control fish (C. viridis) over Gobiodon. When targeting a goby, the predator did not prefer one species over the other. Contrary to our expectations that toxic gobies are generally avoided, gobies were often captured, but they were expelled quickly, repeatedly and alive. This unusual post‐capture avoidance confirms that these gobies have a very good chance of surviving attacks in the field due to their skin toxins. Nonetheless, some gobies were consumed: the coral shelter may therefore also provide additional protection, with toxins protecting them mainly during movement between corals. In summary, chemical deterrence by crinotoxic fishes seems to be far more efficient in predation avoidance than in physical deterrence involving body squamation and/or strong fin spines. 相似文献
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This article reviews the types and effectiveness of marine mammal mitigation measures used during some naval activities worldwide. The three main standard methods used to mitigate the potential impacts of naval sonar sound on marine mammals are (1) time/area planning (of exercises/active sonar use) to avoid marine mammals; (2) implementation of operational procedures (e.g. ‘soft start’ - where sound levels are gradually increased over time); and (3) monitoring of animals for the purpose of maintaining an ‘exclusion zone’ around the sound source. Suggestions towards a minimum worldwide mitigation standard are made. 相似文献
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森林火灾与气象条件的关系及其预报和防御 总被引:3,自引:0,他引:3
分析了湿度、温度、风、降水等气象要素及地形地貌与林火发生的关系,介绍了森林火险等级预报方法,并提出了林火防范措施。 相似文献
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