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我国地方性氟病的地球化学问题 总被引：18，自引：0，他引：18
Endemic fluorine disease is a chronic fluorine poisoning caused by high level of fluorine in drinking water or foods. Incidence of this disease has been knowu in many parts of the world. In China its occurrence has been observed in the Northeast, Northwest, Southwest and some other localities. Investigation shows that it is closely related to geochemical environment: Major fluorine sources in nature include fluorinerich volcanic rocks, calcareous dolomites, phosphorus-bearing rocks/loess and Quarternary loose sediments. Under special conditions fluorine is concentrated in ground water or soil and seeks its way into human body through diet. Areas With high fluorine concentration responsible for the fluorine disease can be classified into four types, depending on characteristics of geochemical environment: (1) Arid and semiarid calcium-rich soda saline areas; (2) Semiarid, alternatively marine-terrestrial strata with a high degree of salinity; (3) Semihumid iron- and aluminum-rich intermediate-acid soils; (4) Localities where fluorine-rich rocks or deposits are developed;and those with high fluorine content as a result of industrial pollution. Based on medical statistics and chemical analyses, of water, soil, food and other related samplcs,this work will provide a scientific baekground for the prevention and control of fluorine disease. 相似文献
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Discussed in this paper are the regularities governing the prevalence of Keshan disease and its relationship te the local rock type, soil, vegetation, climate and landform, as well aa to the characteristic variations of stereo-environment- environmental gradient in Yunnan Province. Based upon the foregoing discussion, the gradations of environmental quality and the coefficients of environmental quality mirroring the general picture of physical environment there have been determined, and a model of environmental quality has been established with an attempt to detail the relationship between the factors of environmental geology and Keshan disease. 相似文献
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通过江西赣南及邻区（23.66°N～27.20°N,113.50°E～118.84°E）中等地震时、空、强和地震活动频度、b值、应变能释放特征分析。结果表明,该地区具有中强地震活动背景,现代小地震呈现密集成带分布特点。中强以上地震序列以主余震型和震群型地震为主。1971年以来地震活动持续活跃,ML≥4.0地震呈现明显的群聚性质,主要表现为地震活动的空间和时间集中现象;ML≥3.5地震活动具有周期性特征,包括高活跃期、平静期和发生破坏性地震事件;b值一直低于年平均值时,中强以上地震活跃;在中强地震活跃之前,应变能释放曲线的速率呈现出加速变化的趋势。本研究结果为该地区预测地震的时、空、强提供了一些重要的参考信息,有助于对该地区的地震活动情况进行密切观测。 相似文献
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贵州草海地区持续发展能力建设吴丰昌，万国江，余志成（中国科学院地球化学研究所．贵阳５５０００２）关键词持续发展，草海，贵州草海位于贵州西部的威宁县境内，是一个由碳酸盐岩形成的喀斯特盆地，积水成湖（因其水草丰富而得名，据考查唯管束植物就有一百余种）。目... 相似文献
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微量元素钼预防克山病的实验研究 总被引：2，自引：0，他引：2
The role of trace element Mo in the prevention of Keshan disease is a new subject in environmental geochemistry. Experimental observations have shown that the natnral incidence of Keshan disease has dropped obviously among inhabitants in the Keshan disease-affeeted areas as a result of six-year successive spreading of anomium molybdate in the crop fields because in doing so the level of molybdenum has been enhaneed in grain crops while the concentrations of nitrates and nitrites have been reduced remarkably in the environment. Experimental results demonstrate that molybdenum may play an effective role in the prevention of Keshan disease. 相似文献
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