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51.
关中盆地地-气系统灾变的节律性及耦合关系   总被引:1,自引:0,他引:1  
依据丰富而系统的历史资料,建立了关中盆地历史地震与旱涝灾害两个数据库,分析了近2000a来地-气系统环境灾变的节律性及耦合关系。结果发现:(1)地震活动具有一定的节律性,并先后经历了3个平静期和3个活跃期,平静期与活跃期呈交替出现,具有3~4个世纪的周期;(2)较为严重的干旱、洪涝灾害亦具有一定的周期性,先后经历了2个洪涝期和3个干旱期,其较长尺度的转换周期亦为3~4个世纪;(3)在世纪尺度上,地震活动与旱涝灾害具有某种耦合关系,表现为在地震活动的活跃期,旱涝灾害呈多发性,而在地震活动的平静期,旱涝灾害较为稀少;(4)以较大级别的地震群发为节点,地气系统环境灾变的耦合关系具有先旱→后震→再涝的演替特征。基于上述事实,提出了一个地-气系统环境灾变的概念模型,对地震与旱涝灾害的耦合关系给出了确定性解释。为关中盆地世纪尺度的环境灾变群发性预测提供了新的依据。  相似文献   
52.
重建湖泊水位历史、掌握其演变规律和机制,对水资源管理、生态环境保护、旱涝灾害防治以及认识区域水文气候变化机制皆有重要意义.中国西南地区拥有大量湖泊,其水位变化及驱动机制广受关注.本文通过汇总历史文献记录并将其与邻近地区的其他湖泊水位重建进行比较,总结了过去一千年中国西南地区湖泊水位的变化.结果显示中国西南地区近千年的湖...  相似文献   
53.
南京典型古建筑的消防现状调查和消防对策   总被引:1,自引:1,他引:0  
通过对江苏南京代表性古建筑朝天宫、甘熙故居、鸡鸣寺和净觉寺的实地深入调查,从结构、材料、内容、布局和环境等方面分析了古建筑普遍存在的火灾危险性,考察了古建筑中现代消防设施建设、消防资金投入、消防管理措施和现代消防材料和技术应用的现状,发现多数古建筑在消防防护方面仍处于保守、常规、落后和消极的状态。为实现对古建筑价值的最大限度保护,应从消防安全布局、消防站建设、消防通道设计、消防给水供应、消防通讯保障、消防装备配置等方面进行性能化设计和规划;在遵循“修旧如旧”的修缮和维护原则下,需要勇于尝试和接纳纳米材料等新型化学保护材料和技术。  相似文献   
54.
河北省旱涝灾害历史特征研究   总被引:3,自引:2,他引:1  
通过分析河北省旱涝灾害的历史状况,得出黉灾呈逐年减轻、时灾呈逐年加重的认识,旱灾是河北省的一种主要自然灾害,探讨了该省旱涝灾害的时空分布规律,在时间上具有季节性、持续性和阶段性,在空间上具有地域性,对增强水患意识,防汛抗旱,今后的防灾抗灾提供了科学依据。  相似文献   
55.
The problem of climate change is a global challenge.It is closely associated with social development and human survival,and it has a significant impact to all countries on energy development,economic competitiveness,technological innovation,and way of life.In recent years,with the rapid economic development in China,there is a rumor that the rapid growth of China’s carbon dioxide emission offset the efforts of the international community in reducing emissions,and China should bear the international responsibility corresponding to its significant role in greenhouse gas emission,which obviously are unfair and not objective.As this paper reveals,"China environment responsibility" that is the socalled "China environment threat" or theories,China has made a positive contribution to addressing the climate change in the past and China will still be the backbone on the protection of global climate in the future.  相似文献   
56.
The problem of climate change is a global challenge. It is closely associated with social development and human survival, and it has a significant impact to all countries on energy develop- ment, economic competitiveness, technological innovation, and way of life. In recent years, with the rapid economic development in China, there is a rumor that the rapid growth of China's carbon dioxide emission offset the efforts of the international community in reducing emissions, and China should bear the international responsibility corresponding to its significant role in greenhouse gas emission, which obviously are unfair and not objective. As this paper reveals, "China environment responsibility" that is the socalled "China environment threat" or theories, China has made a positive contribution to addressing the climate change in the past and China will still be the backbone on the protection of global climate in the future.  相似文献   
57.
While the presence of lead in urban soils from residential lead paint and leaded gasoline is well documented, the relative contribution of lead from area historical industrial activities is not. This study examined the connection between historical industrial sources of lead in Portland, Maine, USA from 1860 to 1970 to current, spatial distributions of soil lead. Collecting 1859 surface and 122 sub-surface soil samples in accordance with USEPA's Lead Safe Yard Protocols, lead concentrations varied from 9 mg/kg to >100,000 mg/kg with most of the samples greater than USEPA's critical value for lead (400 mg/kg). Using historical documents, probable sources of lead were mapped. In comparing two datasets, no clear relationship emerged. Findings were hampered by inability to sample under large areas of impervious surfaces and private properties. Because of lead's immobility in soil, one would expect decreasing concentration with depth, but lead concentrations varied with depth and location. The haphazard dumping of lead-contaminated industrial waste and the relocation of contaminated fill are likely factors. These findings suggest that in urban areas where multiple historical sources of lead existed, surface sampling to determine presence of lead may not be sufficient to protect public health.  相似文献   
58.
Abstract: The commercial trade of wildlife occurs on a global scale. In addition to removing animals from their native populations, this trade may lead to the release and subsequent introduction of nonindigenous species and the pathogens they carry. Emerging infectious diseases, such as chytridiomycosis caused by the chytrid fungus Batrachochytrium dendrobatidis (Bd), and ranaviral disease have spread with global trade in amphibians and are linked to amphibian declines and die‐offs worldwide, which suggests that the commercial trade in amphibians may be a source of pathogen pollution. We screened tiger salamanders involved in the bait trade in the western United States for both ranaviruses and Bd with polymerase chain reaction and used oral reports from bait shops and ranavirus DNA sequences from infected bait salamanders to determine how these animals and their pathogens are moved geographically by commerce. In addition, we conducted 2 surveys of anglers to determine how often tiger salamanders are used as bait and how often they are released into fishing waters by anglers, and organized bait‐shop surveys to determine whether tiger salamanders are released back into the wild after being housed in bait shops. Ranaviruses were detected in the tiger salamander bait trade in Arizona, Colorado, and New Mexico, and Bd was detected in Arizona bait shops. Ranaviruses were spread geographically through the bait trade. All tiger salamanders in the bait trade were collected from the wild, and in general they moved east to west and north to south, bringing with them their multiple ranavirus strains. Finally, 26–73% of anglers used tiger salamanders as fishing bait, 26–67% of anglers released tiger salamanders bought as bait into fishing waters, and 4% of bait shops released tiger salamanders back into the wild after they were housed in shops with infected animals. The tiger salamander bait trade in the western United States is a useful model for understanding the consequences of the unregulated anthropogenic movement of amphibians and their pathogens through trade.  相似文献   
59.
Fisheries management is increasingly transitioning towards collaborative governance. Collaborative systems depend on stakeholders’ capacity to design and implement legitimate and scientifically robust management plans within collective action arenas. Here we propose that collaborative governance outcomes, in fisheries management, will benefit from using structured participatory decision making frameworks that enhance deliberative thinking among stakeholders. We tested our approach in the artisanal fishery of Chile, an important producer of marine resources. Recently in 2013, Chile made important changes to fisheries policies by creating multi-sectorial management committees to manage de facto open access fishing areas. We applied a structured decision making framework to inform the restructuring of a management plan within a committee. As a result, we identified goals,objectives and indicators, including social, economic, biological and ecological dimensions; we explored tradeoffs, assessing the relative importance of the objectives; finally, we created scenarios and prioritized alternatives, reflecting on the interplay between self-regulation and government control. Members of the management committee were able to rationalize the different steps of the framework and identify ways forward which highlighted the importance of self-regulation in comparison to central authorities’ control. We concluded that structured decision making promotes spaces for rational analysis of alternatives costs and benefits. Promoting deliberative thinking in fisheries management can improve equity, legitimacy and sustainability of collaborative governance.  相似文献   
60.
濮阳旅游资源评价与可持续开发思路   总被引:4,自引:0,他引:4  
濮阳旅游资源以醇厚的历史文化资源为主 ,具有潜在性和开发难度大的特点。资源现状开发初具规模 ,但缺乏系统性和独特性 ,可持续的开发思路是历史文化资源的保护性开发 ,文化生态旅游式开发 ,多层次立体开发和区域联合式开发  相似文献   
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