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1.
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   
2.
Empirical aspects of the movement of strontium through the food chain suggest that the level of bone strontium can be used as an indicator of the percentage of meat in human diet. In general, skeletal remains from agricultural peoples are expected to have high bone strontium levels relative to hunter-gatherers from the same geographical region because plants contain relatively higher amounts of strontium when compared with animal products. The results of the study described in this paper, however, indicate that the inclusion of molluscs as a component of the diet may produce the opposite of the expected strontium values. Burials from an Archaic (c. 2500 BC) hunting-gathering population excavated from Luo25, an archaeological site in northern Alabama, USA, exhibit a mean bone strontium level ( atomic absorption; neutron activation) that is higher than the mean level from an agricultural Mississippian (c. AD 1400) population ( atomic absorption; neutron activation) that was buried at the same site. The samples were analysed by two techniques (atomic absorption spectrometry and neutron activation analysis) and the results compared favourably; therefore, the results can be accepted as valid rather than being due to technique error. We propose that the ingestion of molluscs, whose meat is known to contain large amounts of strontium, has produced this reversal from expected results.  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.
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   
6.
The number of studies using trace elements as indicators of diet has increased with time, but the majority have used few elements and a small sample. The present study has as a principal objective a multi-element analysis of diet in a large sample in which diagenetic changes have been shown to be unimportant. The analysis was made using concentrations of seven elements—Sr, Ba, Mg, Cu, Zn, V and Ca—in 197 individuals from the necropolis of ‘S' Illot des Porros’ (Majorca, Spain). The results show that these individuals would have had a mixed diet with a high meat component, principally of marine origin (molluscs and fish), but with an important consumption of seeds and cereals and a low proportion of vegetables.  相似文献   
7.
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   
8.
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   
9.
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   
10.
Based on extensive fieldwork as well as a discourse and content analysis of relevant government documents, we identify two important rescalings around China's South-North Water Transfer Project (SNWTP), the world's largest water project to date. These rescalings work in tandem with a discourse around the long-held Chinese ethic of “eating bitterness” (enduring hardship or chiku) and serve to include and exclude stakeholders and manufacture public acceptance of the project in the face of significant social, economic, and ecological trade-offs. We focus on two rescalings—one a more orthodox upscaling to the central government and one that relies on a fragmented, geographically disembodied, subnational scalar construction. Both rescalings operate in representational spaces, but also have important material dimensions. The case of the SNWTP demonstrates how rescaling is not only about power struggles between administrative political units, but can also be used as a political tool to exert power over particular groups of people.  相似文献   
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