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41.
全球气候博弈的实质是各国在承认地球资源和承载能力有限的前提下力图在未来世界能源、资源分配和温室气体排放空间的分配中获得尽可能大的份额。美国与中国的个案分析表明:气候公地的悲剧源于博弈主体对于自身短期利益的追求及对人类根本利益的忽视。具体说来,发达国家受制于自由民主制度放纵的内部博弈,而发展中国家则更多的受制于国际体系的无政府状态与不平等现状下外部博弈引发的安全需求。气候危机将人类带入困境的同时也加速了人类从工业文明迈向生态文明的进程。公地悲剧的出路在于强化国家在应对气候方面的作用;加强转型时期政策的系统性;以政治上的预防原则对应吉登斯悖论;国际社会对于责任认定的公平化。 相似文献
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Information on the freshwater fauna of the remote Arctic territories is very patchy, and most of the isolated islands of the Arctic Ocean remain absolutely unexplored. The pioneer data on the species composition of microcrustaceans of Shokalsky Island (northwest Siberia, Russia) is reported here. The initial three-year research revealed a total of 31 new for the area species of Cladocera and Copepoda, including new records for the whole of northwestern Siberia. Comparing the interannual differences in faunal composition, we suggested the hypothesis of the existence of a cryptic pool of species’ resting stages, which can invade the community in the event of favourable environmental conditions in the Arctic freshwaters. We also compiled all the available data from different parts of northern Siberia and compared them with the fauna of Shokalsky Island to analyse the connection between the diversity and distributional patterns of copepods and cladoceran species and the climate conditions of different territories. 相似文献
44.
Temperature changes are known to affect the social and environmental determinants of health in various ways. Consequently, excess deaths as a result of extreme weather conditions may increase over the coming decades because of climate change. In this paper, the relationship between trends in mortality and trends in temperature change (as a proxy) is investigated using annual data and for specified (warm and cold) periods during the year in the UK. A thoughtful statistical analysis is implemented and a new stochastic, central mortality rate model is proposed. The new model encompasses the good features of the Lee and Carter (Journal of the American Statistical Association, 1992, 87: 659–671) model and its recent extensions, and for the very first time includes an exogenous factor which is a temperature‐related factor. The new model is shown to provide a significantly better‐fitting performance and more interpretable forecasts. An illustrative example of pricing a life insurance product is provided and discussed. 相似文献
45.
在全球气候变化的背景下,特殊的气候条件引发的城市突发公共卫生事件不容忽视.城市规划是政府确保公共卫生安全的重要手段,从城市规划角度预防及控制气候变化带来的突发公共卫生事件并作出一定的规划响应,对于提升寒地城市居民健康水平具有重要意义.以寒地城市为例,分析了地域气候特征对突发公共卫生事件的影响,结合城乡人口空间分布、土地... 相似文献
46.
马君 《系统工程理论与实践》2016,36(4):945-957
激活员工创造力、凝聚新的发展动力是企业面临的紧迫任务.基于系统而权变的视角,以"语义感知-心理计量-行为强化"为理论主线,针对60个团队274名员工样本,运用跨层次分析考察了不同成就动机氛围下奖励(水平和结构)对创造力的影响.结果表明,精熟氛围、扁平型奖励结构正向影响突破式创造力;表现氛围、陡峭型奖励结构正向影响渐进式创造力:三项交互检验显示,在高精熟氛围及扁平型结构下,提高奖励水平能够更好地激活突破式创造力;而在高表现氛围和陡峭性结构下,提高奖励水平能够更好地激活渐进式创造力.研究揭示,成就动机氛围、奖励结构与创造力类型之间存在一种相对最优的匹配关系.蕴含的实践价值在于,企业应从执行角度在项目团队营造表现动机氛围并辅以竞争性激励结构,以提升渐进式创造力,快速获取局部竞争优势;但鉴于"渐进式创新有余,突破式创新不足"的企业创新格局,我们更应从战略视角在技术核心部门营造精熟氛围并辅以高位均衡的激励模式,以催生突破式创造力,赢得持久竞争优势. 相似文献
47.
《高技术通讯(英文版)》2016,(4):343-349
Vegetation cover change is critical for understanding impacts and responses of vegetation to climate change. A study found that vegetation in the regions between 45°N-70°N was increasing using normalized difference vegetation index( NDVI) from 1981 to 1991 ten years ago. The global vegetation growth has changed because of climate change in recent twelve years( 2001- 2012). After thorough analysis based on satellite data,it is found that it is evident that the global vegetation changed( NDVI) little,and it is increasing slightly in Northern hemisphere while it is decreasing slightly in Southern Hemisphere. For different latitudes,vegetation is increasing 0.17% every year from 60°N to 70 °N( R~2= 0.47,P 0.013),while the vegetation is decreasing 0.11% every year from 10°N to 10° S( R~2= 0.54,P 0.004). For different continents,the vegetation in South America is decreasing 0.16% every year( R~2= 0.78,P 0.0001) and it is increasing 0.05% every year in Asia( R~2= 0.28,P 0.072) and 0.25% every year in Oceania( R~2= 0.24,P 0.1). The analysis of global vegetation in different seasons indicates that spatial distribution of global temperature and water vapor will affect the spatial distribution of vegetation,in turn,the spatial distribution of vegetation will also regulate the global temperature and water vapor spatial distribution at large scale. The growth and distribution of vegetation are mainly caused by the orbit of the celestial bodies,and a big data model based on gravitational-magmatic change with the solar or the galactic system as its center is proposed to be built for analyzing how the earth's orbit position in the solar and galaxy system affects spatial-temporal variations of global vegetation and temperature at large scale. These findings promise a holistic understanding of the global climate change and potential underlying mechanisms. 相似文献
48.
Surface pollen assemblages of human-disturbed vegetation and their relationship with vegetation and climate in Northeast China 总被引:1,自引:0,他引:1
ManYue Li YueCong Li QingHai Xu RuiMing Pang Wei Ding ShengRui Zhang ZhiGuo He 《科学通报(英文版)》2012,57(5):535-547
Pollen assemblages of 53 surface pollen samples from farmlands and wastelands in Northeast China were analyzed. Tree pollen percentages were usually higher than 30%, with Pinus (26.9%), Quercus (0.9%), Betula (0.9%) and Populus (0.7%) as the major types, and herb pollen percentages were usually higher than 50%, with weedy Poaceae (8.7%), Chenopodiaceae (7.1%), Artemisia (1.9%) and Compositae (3.5%) as the major taxa. Thus, the pollen assemblages were consistent with the regional vegetation compositions. However, there were differences in pollen assemblages among regions, especially among different geomorphological units. For example, in the mountains, there were more types of tree pollen and higher total percentages (average 42%) than in other areas, while cereal pollen percentages were lowest (11.2%). In the hills and high plains, herbs made up more than 60% of the pollens, with cereals (average 53.6%) the dominant type. In the low plains, pollen types were similar to those in the hills and high plains, but total pollen concentrations and the proportion of Concentricystes were much higher, while cereal pollen percentages were slightly lower (average 41.6%). Pollen assemblages in different land use types also differed. For example, in farmland, cereal pollen percentages were more than 40% and Chenopodiaceae was usually less than 2.5%, while in wasteland, weedy Poaceae was usually less than 10% and Chenopodiaceae was usually higher than 25%. Total pollen concentrations in farmland (average 3909 grains/g) were much lower than in wasteland (average 15074 grains/g). Redundancy analysis revealed that pollen assemblages were significantly negatively correlated with mean annual temperature (-0.73) and July mean temperature (-0.81) and significantly positively correlated with mean annual precipitation (0.48), indicating that pollen assemblages in the artificial or human-disturbed vegetation reflect regional climate well. Comparison of pollen assemblages in different areas of northern China showed that pollen concentrations reflect the intensities of human impact to some degree. For example, pollen concentrations decrease as human impacts increase in intensity. The cereal pollen proportions in farmland differed by area. In Northeast China, cereal pollen proportions were distinctly higher than in most other areas of northern China, suggesting differences in planting habits and climate. 相似文献
49.
《Journal of Natural History》2012,46(37-38):2375-2396
This article marks the beginning of a short series on the butterfly fauna of Mount Kilimanjaro. It commences with a brief overview of the topography, tectonic history, climate, ecological zonation and conservation significance of Africa's highest mountain. Following an introductory account to the butterfly fauna, the rest of this paper presents an annotated checklist of the swallowtails (Papilionidae). Eight papilionid species are currently believed to occur within the main forest zone, from 1800 to 2800 m (in places this zone extends down to c.1600 m). Another 10 have been recorded from the lower slopes, which include some disturbed forest and forest relicts, from 700–1800 m. The need for better data is discussed in light of the suggestion that the butterflies of Mount Kilimanjaro could become a focal group for monitoring effects of climate change. An identification key to families, together with a key to the swallowtail species and colour illustrations of adults, are included as online Supplementary Information. 相似文献
50.
Climate extremes, such as extreme hot temperatures and heat waves, can have dramatic societal, economic, and ecological consequences. China has experienced remarkable interannual and decadal changes in hot extremes during the last several decades. However, the underlying mechanisms responsible for changes in the hot extremes over China have not been clearly identified. In this study, we investigate the role of land-atmosphere coupling for hot days and heat waves during summer over China using two long-term ... 相似文献