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1.
水资源短缺一直制约着京津唐地区经济和社会的发展。20世纪70年代,因缺水引发的经济、社会问题逐渐凸显,促使中央和地方政府开始考虑实施跨流域调水工程。引滦工程作为北方最大的跨流域调水工程,其决策经历了曲折的过程。1958年,北京和唐山曾分别提出引滦河水的设想,唐山还实施了引滦入还和引还入陡工程。1972年,海河流域大旱促使中央做出加快实施引滦工程的决定,但由于地质情况复杂等原因,引滦工程设计方案被反复修改。1981年,天津提出了单独引滦济津路线并得到了中央的支持。引滦工程对缓解京津唐用水紧张发挥了重要作用,天津是引滦工程受益最大的地区。  相似文献   
2.
The paper offers a geographical interpretation of the evolving technical, political, and economic intricacy of large dams. It incorporates existing hydropolitical scholarship and the notion of the Chinese Water Machine to reframe dams as assemblages built by specific political, financial and technical processes in particular socioenvironmental regions. The paper examines the continuity of hydropolitical relationships through a genealogical inquiry into the formulation and materialisation of Ghana's three dams: the Akosombo and Kpong dams built during the Cold War, backed by Western lenders and engineering companies; and the Bui dam commissioned in the 2010s, with support from China. Based on fieldwork in Ghana and China, as well as documentary evidence, the paper argues that the thinking, planning and building of dams interconnect the host regime and external techno-financial actors with their floating political-economic interests, but in a durable way. Sometimes, even if little concrete is actually poured, the symbolic power of dams endures, transforms, and at certain times and places expands, through events and discourses of national and international interest groups pursuing their own purposes, albeit with the replacement of influential individuals and powerful institutions, and regardless of the involvement of Western, Chinese and/or other actors. Ruptures exist but do not necessarily break the continuity of dam assemblages. The emergence of an opposition assemblage that battles against dams is a more recent complexity.  相似文献   
3.
Climate-driven water variability is a natural phenomenon that is observed across river basins, but one that is predicted to increase due to climate change. Environmental change of this kind may aggravate political tensions, especially in regions which are not equipped with an appropriate institutional apparatus. Increased variability is also likely to challenge regions with existing institutional capacity. We argue that our best attempts to assess the ability of states to deal with variability in the future rest with considering how agreements have fared in the past. In this paper, we explore treaty effectiveness, or treaty resilience, by investigating whether particular water allocation and institutional mechanisms help mitigate inter-country tensions over shared water. We use water-related events from the Basins at Risk events database as a dependent variable to test particular hypotheses regarding the impact of treaty design on conflict and cooperation over time. A broad set of climatic, geographic, political, and economic variables are used as controls. The analysis is conducted for the years 1948–2001 using the country dyad as the level of observation. Findings pertaining to our primary explanatory variables suggest that country dyads governed by treaties with water allocation mechanisms exhibiting both flexibility and specificity evince more cooperative behavior. Country dyads governed by treaties with a larger sum of institutional mechanisms likewise evince a higher level of cooperation, although certain institutional mechanisms appear to be more important than others.  相似文献   
4.
本工作借鉴已有的研究成果,并辅以相关调研,试图探究修复用水选择的重要性以及如何选择修复用水的问题。为此,通过对国内外文献的分析以及相关问题的调研,综述了生活饮用水中对纸张长期保存有害的污染物及其对纸张纤维的危害。通过对修复用水实例的讨论,指出:纸质藏品的修复须采用净化水,即通过逆渗透、去离子处理等方法净化后并达到一定电阻率的纯水,在条件许可的情况下,采用电阻率更高的超纯水更好;须现制现用以保证使用过程中净化水不被再次污染;在设备方面,选择小型纯水系统更能保证用水质量。  相似文献   
5.
Federico Ferretti 《对极》2019,51(4):1123-1145
This paper argues for a rediscovery and reassessment of the contributions that humanistic approaches can make to critical and radical geographies. Based on an exploration of the archives of Anne Buttimer (1938–2017) and drawing upon Paulo Freire's notion of conscientização (awareness of oppression accompanied by direct action for liberation), a concept that inspired the International Dialogue Project (1977–1988), I explore Buttimer's engagement with radical geographers and geographies. My main argument is that Buttimer's notions of “dialogue” and “catalysis”, which she put into practice through international and multilingual networking, should be viewed as theory‐praxes in a relational and Freirean sense. In extending and putting critically in communication literature on radical pedagogies, transnational feminism and the “limits to dialogue”, this paper discusses Buttimer's unpublished correspondence with geographers such as David Harvey, William Bunge, Myrna Breitbart, Milton Santos and others, and her engagement with radical geographical traditions like anarchism, repositioning “humanism” vis‐à‐vis the fields of critical and radical geography.  相似文献   
6.
This article compares and contrasts the approaches of the NewDeal Federal Writers' Project and the Columbia Oral HistoryProgram in an effort to reconsider the paradoxical history oforal history research in the United States and its relationshipto how many oral historians today look at their work and thehistory of their field. As it turns out, the theoretical andsocial concerns of the FWP projects are closer to current theoreticalconcerns of oral historians than the work Allan Nevins conductedin the early years of the Columbia project. The article alsoshows how awareness of the history of the intellectual and culturalcurrents that affect oral history projects in general, and theFWP's work in particular—interviews with former slaves,tenant farmers, industrial workers, and members of ethnic minorities—canhelp us analyze and use those materials. It argues that an awarenessof continuity and discontinuity in the history of oral historymakes it possible for today's oral historians to have a productivedialogue with their predecessors in the field.  相似文献   
7.
为配合南水北调工程建设,河南省文物考古研究所对安阳固岸墓地进行了考古发掘,清理出大批战国至隋代的墓葬,其中M2是一座保存较为完整的北齐时期的墓葬,出土器物60余件,尤其是出土的陶俑和镇墓兽十分精美,为研究北齐时期葬俗、葬制提供了珍贵的实物资料。  相似文献   
8.
杨华 《东南文化》2007,(6):6-13
通过对三峡地区长江沿岸的考古发掘,发现了远古时期人类居住遗址的所处位置、海拔高度,尤其是遗址地层堆积中往往还叠压有洪水过后的淤积,根据这些洪水淤沙层的位置以及其上、下堆积层中包含物的年代,我们可推测出远古时期三峡地区长江发生洪水的大致年代,洪水水位的海拔高度,看看那时的河床究竟是比现在高、还是低,从而为当今人们治理长江、开发长江提供科学的证据。  相似文献   
9.
五千年前陶质建材的测试研究   总被引:1,自引:0,他引:1  
迄今为止的考古发掘表明,我国最早的陶质建材,应该是距今5500年左右的凌家滩“红陶块”。考古学家推测其原料为粘土矿物,烧成温度约800~1000℃,且其物理性能与砖质建材较为接近,应为“砖的雏形”,为此,本工作测试分析了凌家滩“红陶块”的物相组成、烧成温度、吸水率与抗压强度,同时对比分析了明砖、汉砖、现代砖的物理性能,发现“红陶块”系粘土原料在950℃以上温度烧制而成,其吸水率和抗压强度由外向内呈梯度变化,内层的抗压强度、吸水率接近于现代砖和汉砖,业已超过明砖样品,所有这些分析结果,皆支持考古学家关于凌家滩“红陶块”为砖的雏型的推测。  相似文献   
10.
非均质的砂砾石层是莫高窟壁画的主要墙体,但砂砾石层的非均质性如何在水盐运移过程中发挥作用却还不清楚。为此,通过在108窟西壁面上1 m×1 m和2 m×2 m范围的三维高密度电阻率成像监测,发现在这些区域上,墙体电阻率的空间分布都是非均匀的,低阻值区域在空间位置、大小和形状上都会随时间而变化。这明确说明在构成墙体的非均质砂砾石层内存在着重要的水分饱和与非饱和过程(再分配过程),正是这一不断重复的饱和与非饱和过程促进了墙体内水分的运移和盐分在一些特定区域的聚集。研究成果对全面认识莫高窟墙体内的水盐运移机理,减轻和防治壁画盐害都具有重要意义。  相似文献   
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