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Abstract

Innovations for the British Army during World War I included use of a military geologist to compile 'water supply' maps and to guide well drilling. Between June 1915 and November 1918, W. B. R. King served as a staff lieutenant at General Headquarters of the British Expeditionary Force deployed on the Western Front. He pioneered British development of water supply maps for parts of Belgium and northern France, in several different styles and at scales of 1 : 100 000, 1 : 250 000 and 1 : 40 000. These assisted planning for advances into enemy-occupied territory or the development of water supply infrastructure within the region held ultimately by five British armies: in total about 1,500,000 men with some 500,000 horses and mules, each man/animal requiring on average 10 gallons (45 L) per day of potable water. The maps guided emplacement of over 470 military boreholes to supply drinking water to British forces, especially in provinces underlain by Cretaceous Chalk: Picardy and Artois. German forces also made use of military geologists at the Front, but in much greater number: up to about 300 in total. Water supply tasks were given high priority, and German water supply maps were finally standardized like other medium scale German geotechnical maps at 1 : 25 000. Six geologists were deployed with the American Expeditionary Force late in the war, and for their sector of the Front compiled at least two water supply maps at 1 : 80 000, and 11 at 1 : 50 000 that were supported by explanatory reports. Wartime imperatives thus generated expertise in hydrogeology that became available for civilian use post-war, and laid the foundation for further military development during World War II.  相似文献   
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关于长江冲淡水路径的若干问题   总被引:2,自引:0,他引:2  
自从1980年6月中美关于长江口及其邻近陆架海区的沉积动力学联合考察开始以来,关于长江径流人海后路径的时空变化问题,引起了中外学者的广泛兴趣。 在这次中美联合考察之前,作者曾根据1980年以前的实测水文资料和余流资料,分析了洪水期本区的盐度分布和海流结构。本文目的是根据中美联合考察所得到的资料和历史资料,对长江冲淡水实测路径的性状作进一步的分析,并拟对影响长江冲淡水复杂多变路径的若干动力学问题作一初步分析。  相似文献   
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主要介绍了黑河流域遥感—地面观测同步试验(Watershed Allied Telemetry Experimental Research,WATER)的第二阶段,即以森林水文过程及中游干旱区生态水文过程为主要目标的中游试验。简要阐述了试验目标与研究内容,重点介绍了航空飞行试验、地面同步试验和加密观测试验的样方布置、数据获取与处理以及研究进展与展望。中游试验的核心研究内容是紧密围绕森林水文及中游干旱区水文的水循环问题开展航空遥感、地面同步观测试验和水文与生态参数加密观测试验,改善蒸散发反演模型和算法,探讨尺度转换方法。其中航空试验使用了微波辐射计、激光雷达(LiDAR)、高光谱成像仪、热红外成像仪和多光谱CCD相机5类传感器,飞行了17个架次和72个小时。  相似文献   
4.
Continuous CTD data from a series of recent cruises show that the distribution of the water mass characteristics in the central Benguela region from the Orange River mouth (28°38'S) to alvis Bay (22°57'S) is discontinuous in the central and intermediate waters at about the latitude of Lüderitz (26°40'S), Namibia. The central and intermediate water masses at the shelf edge and shelf break north of the Lüderitz upwelling cell have a high salinity relative to the potential temperature compared to similar waters south of the upwelling cell. It is shown that the feed waters for the wind-induced upwelling on the shelf to the north and south of the Lüderitz discontinuity are different in character and source. The distribution of the water masses shows that the shelf-edge poleward undercurrent provides low-oxygen water from different regions in the Atlantic Ocean to be upwelled onto the shelf. North of th Lüderitz upwelling cell, the central and intermediate waters come from the oxygen-depleted Angola Basin, whereas south of the discontinuity those waters are from the interior of the adjacent Cape Basin, which is less oxygen-deficient. This has implications for the dispersion of low-oxygen water and the triggering of anoxic events, and consequences for the biota on the shelf, including commercially important fish species.  相似文献   
5.
The distribution of five dominant calanoid copepods was related to different water masses in the Angola-Benguela Front system. Five water bodies were identified by principal component analysis, on the basis of abiotic parameter such as temperature, salinity, dissolved oxygen, phosphate, silicate, nitrate and nitrite. These parameters were reduced to single factors and arranged along two principal component axes. The copepod species incuded females and copepodites C5 of Calanoides carinatus and females of Metridia lucens, Centropages brachiatus, Nannocalanus minor and Aetideopsis carinata. The water bodies identified in the frontal system were related to currents, upwelling processes, an oxygen minimum layer and biological modification. The different copepod species, as well as the two ontogenetic stages of C. carinatus, showed clear preference for specific water bodies, and their behavioural and physiological adaptations to the environment are discussed.  相似文献   
6.
近地层能量平衡闭合问题——综述及个例分析   总被引:7,自引:4,他引:7  
近地层能量闭合问题,即测量到的感热和潜热通量之和一般总小于近地层可利用能量(净辐射与土壤热通量之差),是近20年来困扰地气相互作用实验研究的主要难点之一。对国内外有关研究现状做了综述,与解决此问题日益迫切的要求相适应,问题的实质及解决途径近年来已逐渐明朗。"涡动相关方法"应用在复杂的大气湍流通量观测中的局限,特别是对低频较大尺度湍流通量的低估,仍是关键所在。在理论分析的基础上,结合2008年部分"黑河综合实验"资料对有关计算结果做了具体介绍。以阿柔站6天连续资料为例,仔细计算土壤浅层热储存,在涡动相关资料再处理中加上高低频损失修正等,再参考该站大口径闪烁仪(LAS)观测对感热通量的提高,能量闭合率可达到99%,当然这只是个例。许多复杂情况下,较大尺度的涡旋或湍流有组织结构(TOS)会有更明显影响。近地层能量闭合问题的根本解决必须考虑后者的贡献,提高通量观测的时空代表性。  相似文献   
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