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51.
建设中老缅泰国际合作开发区营造景洪市立体开放口岸系统 总被引:1,自引:0,他引:1
本文论述了中老缅泰国际合作开发区建设是澜沧江—湄公河流域开发的优先启动区,是南南合作的新模式,对推动中南半岛次区域合作发挥着先导功能。景洪作为中国西南边境城市,在未来次区域合作中将升格为枢纽城市之一,因此,其开放度要不断扩大,在已具有的国家一类水运口岸基础上,要继续营造国家一类航空口岸、公路口岸,并在跨世纪建造昆明—曼谷铁路时,设置国家一类铁路口岸,同时在中缅240界桩两侧开辟新型的边境贸易旅游区,构筑景洪市全方位立体型开放系统。 相似文献
52.
沙漠化灾害监测评价信息系统空间数据分类编码研究 总被引:2,自引:0,他引:2
介绍本系统空间数据分类编码设计方案、原则及其特点,探索沙漠化灾害监测评价信息系统空间数据分类与编码规范化和标准化的途径,为沙漠化灾害信息的计算机存贮、管理、识别及提取奠定基础。 相似文献
53.
山岳型旅游区人文建筑环境后效与调控模型 总被引:5,自引:1,他引:4
许多山岳型旅游区内或其流域上游,都建有人文建筑,而且在急剧增多,导致自然环境日趋恶化,其中乱建疗养院和旅馆的影响最为严重。通过地监测并全面分析张家界环境演变趋势,发现住宿施对环境的影响,比其他游乐设施更为明显。张家界国家森林公园生态环境的脆弱因子是金鞭溪水质。金鞭溪水质恶化主要表现为蓝藻,绿藻迅速繁殖,感官质量下降。主要原因是磷污染较重,总磷年均值100%超标。本文提出了基于环境脆弱因子的动态阈值调控模型,通过计算得出:在不超出张家界景区最为脆弱的环境因子-金鞭溪水质标准:总磷≤0.02前提下,金鞭溪上游接待区住宿设施生态阈值的动态系列:春季临界床位数为1186,夏季为3057,冬季为545,秋季为333。目前的建筑规模已超过了金鞭溪上游接待区住宿设施生态阈值。 相似文献
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Becky Mansfield 《Geoforum》2003,34(3):329-342
This paper addresses the cultural economy of nature and the material culture of economic practice. Attending to ways that cultural notions about the biophysical world play key roles in political economic conflicts, discussion centers on two recent debates involving the cultural economy of seafood production and trade. The first debate is over whether the label “catfish” should include catfish imported from Vietnam into the United States; the second deals with whether fish and shellfish should be eligible to be certified “organic” under new US regulations. Analysis reveals that the key dynamic in these debates is not necessarily how people think about “nature”, but instead is how people make distinctions about the world. Rather than focusing on what is natural or not, key actors make distinctions among both organisms and environments. The ways that different groups define and enclose the biophysical world works to distinguish places as either appropriate or not for certain kinds of production activities. The overall argument is that significance and meaning of the biophysical become implicated in economic geographies by making distinctions about the world that then become important for how economic activity can work. As such, cultural economic approaches should attend to the ways that the biophysical is involved in relations such as competition and international trade, while nature-society approaches should shift focus from Nature to specific aspects of the biophysical world. 相似文献
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57.
扩频通信技术是基于信息容量和信息传输差错概率理论而建立的先进的无线通讯方式、多次野外实地证实它具有抗干扰性强、可实现码分多址等优点。通过分析传输试验数据,我们有理由相信扩频通信技术在遥测地震台风中具有较高的应用和广阔的发展前景。 相似文献
58.
Since it was first proposed in 2000, the concept of the Anthropocene has evolved in breadth and diversely. The concept encapsulates the new and unprecedented planetary-scale changes resulting from societal transformations and has brought to the fore the social drivers of global change. The concept has revealed tensions between generalized interpretations of humanity’s contribution to global change, and interpretations that are historically, politically and culturally situated. It motivates deep ethical questions about the politics and economics of global change, including diverse interpretations of past causes and future possibilities. As such, more than other concepts, the Anthropocene concept has brought front-and-center epistemological divides between and within the natural and social sciences, and the humanities. It has also brought new opportunities for collaboration. Here we explore the potential and challenges of the concept to encourage integrative understandings of global change and sustainability. Based on bibliometric analysis and literature review, we discuss the now wide acceptance of the term, its interpretive flexibility, the emerging narratives as well as the debates the concept has inspired. We argue that without truly collaborative and integrative research, many of the critical exchanges around the concept are likely to perpetuate fragmented research agendas and to reinforce disciplinary boundaries. This means appreciating the strengths and limitations of different knowledge domains, approaches and perspectives, with the concept of the Anthropocene serving as a bridge, which we encourage researchers and others to cross. This calls for institutional arrangements that facilitate collaborative research, training, and action, yet also depends on more robust and sustained funding for such activities. To illustrate, we briefly discuss three overarching global change problems where novel types of collaborative research could make a difference: (1) Emergent properties of socioecological systems; (2) Urbanization and resource nexus; and (3) Systemic risks and tipping points. Creative tensions around the Anthropocene concept can help the research community to move toward new conceptual syntheses and integrative action-oriented approaches that are needed to producing useful knowledge commensurable with the challenges of global change and sustainability. 相似文献
59.
Erik Mostert 《Physics and Chemistry of the Earth》2009,34(3):142-149
The management of the Rhine is often seen as an exemplary case of international river basin management. In the Rhine basin, countries that went to war with each other twice in the last century have managed to reach agreements on many issues and water quality has improved considerably. The improvement in water quality is often attributed to the activities of the International Commission for the Protection of the Rhine and in particular to its Rhine Action Plan. In order to test this assertion, this paper describes and analyzes the development of international co-operation on the water quality of the Rhine since 1945. It concludes that water quality improvement cannot be attributed to any single factor. Instead, a whole array of interrelated factors are at play, including the European Union, other international fora such as the North Sea Ministerial Conferences, domestic legislation, the activities of environmental NGOs and waterworks, growing environmental awareness, and the changing structure of the industry in the basin. Because of the importance of contextual factors, the Rhine experiences cannot simply be applied to basins with a different context. In many cases, international river basin management may be promoted most effectively by promoting co-operation at the river basin level. In many other cases, however, it may be more effective to identify and then work on the contextual factors that (1) have the biggest leverage effect in the specific case and (2) can be influenced most effectively. 相似文献
60.
1954年2月11日,中国西部河西走廊发生山丹7.3级强烈地震,这是建国以来发生在西北地区的第一个大地震。地震造成47人死亡,332人受伤,数万人无家可归;房屋损坏7277间,估计财产损失远高于2003年山丹6.1级地震灾害的直接经济损失。极震区烈度达Ⅺ度,红寺湖盆地、山丹县城破坏最重,山丹地区受灾面积4800km2。本文简要介绍了山丹地震参数、地震烈度及震区环境;重点描述了房屋建筑物破坏,分析了地震灾害特点及其经济损失估计。最后探讨了这次地震震害的成因、防震减灾的经验及其借鉴意义。 相似文献