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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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岩石在风化过程中释放的碳，是全球碳循环的一个重要组成部分。对碳酸盐岩、泥质岩、花岗岩、玄武岩等母岩以及不同风化阶段和成土过程产物中无机碳的研究表明，碳都有一个从母岩中释放和又重新积累的过程。 相似文献
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土壤表层CO_2的释放与土壤水分波动 总被引：2，自引：0，他引：2
贵州虽地处雨量充沛、气候潮湿的亚热带,但近年来旱地土壤往往出现明显的干湿循环现象,这是因为：１）森林植被遭到破坏,使其对气候的调节功能大不如前,导致出现多年气候异常,最大的年降雨量与最小的年降雨量之间相差５００ｍｍ以上,旱涝灾害频繁;２）喀斯特地貌土... 相似文献
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