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91.
Environment, Development and Sustainability - Environmental deterioration and global warming has created a substantial impact on international companies to incorporate eco-friendly, green supply...  相似文献   
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Environment, Development and Sustainability - Realisation of the sustainable development goals (SDGs) will provide improvements to people's lives and longevity of the planet. The architectural,...  相似文献   
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Russian Journal of Ecology - Populations at the border of ranges are considered more vulnerable than those in the center. However, some recent reviews contradict this hypothesis. We have studied...  相似文献   
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Russian Journal of Ecology - Abstract—We tested a hypothesis about the different abilities of alien and native plants to form arbuscular mycorrhizae. The studies were carried out in the...  相似文献   
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Four 6-mo mark-and-recapture experiments conducted in Long Island Sound, USA, from 1988 to 1990, involving approximately 2250 individual observations, demonstrated that under natural conditions significantly higher mortality (p0.001, chi-square test) occurred amongMya arenaria (L.) with hematopoietic neoplasia than those diagnosed as non-neoplastic. Using a blood-screening technique, the clams were diagnosed and placed in one of three diagnostic groups based on the severity of the disease (the percentage neoplastic cells per total number of blood cells): non-neoplastic (NN), 0%; low-severity neoplastic (LSN), < 50%; high-severity neoplastic (HSN), > 50%. Mortality of those clams initially diagnosed as HSN ranged from 48% to 78%, depending on the test period, as compared to 3% to 21% for the non-neoplastic. Mortality in the LSN treatment varied from 8% to 34%. Both progression and remission were evident in clams at all stages of the disease. Mortality and rates of progression and remission in individuals appeared to be linked to water temperatures. Differential mortality may be responsible for the apparent seasonal cycle of prevalence in populations.  相似文献   
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Natural disasters: a framework for research and teaching   总被引:5,自引:0,他引:5  
Alexander D 《Disasters》1991,15(3):209-226
Natural disasters are defined in this paper by relating the impact of extreme geophysical events to patterns of human vulnerability. Hazard perception is shown to be a factor that limits the mitigation of risk. The historical development of disaster studies is traced and five different schools of thought are identified. The current International Decade for Natural Disaster Reduction (IDNDR) is evaluated critically with regard to its potential for unifying the disparate strands of knowledge and its scope as a vehicle for education.
A pedagogical framework for disaster studies is presented. Time and space provide valuable unifying factors, while the subject matter can be differentiated according to the continua and dichotomies that it presents. In disaster studies as in other branches of higher education, an ecocentric approach is preferable to a technocentric one, as many of the poorer nations of the world, which are most afflicted by natural catastrophe, will have to rely for mitigation on maintaining their ecological sustainability, instead of depending on sophisticated technology. Valuable insights into the impact of environmental extremes on mankind are gained from the study of disasters as human ecology.  相似文献   
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