河北某燃煤电厂周边土壤中砷及其形态分布特征

Characteristics of Distribution and Fractions of Arsenic in the Soil around a Coal-Fired Power Plant

采用高压密闭消解-原子荧光光谱法及分级提取-原子荧光光谱法,对某燃煤电厂周边土壤中的砷(As)总量及As形态进行了分析测定。结果显示,所有采样点土壤中As含量均低于国家标准;土壤垂直方向As含量随采样点深度增加而减少;以燃煤电厂烟囱为原点,土壤水平方向As含量分布符合抛物线特性,且与风向有关;As的存在形态以铁铝水合氧化物结合态和残渣态为主,这些形态的As不易被生物直接吸收利用,对生物的影响较低。

The soil samples were collected from the locations near a coal-fired power plant. The atomic fluorescence spectrometry was applied in the total arsenic detection, and the arsenic in the soil samples was further fractionated into different fractions by a sequential extraction procedure. The results indicate that the arsenic content in the soil samples is below the national environmental quality standards for soil and decreases vertically with the deeper sampling spot. Taking the chimney as the origin, the arsenic content is distributed horizontally in agreement with parabola characteristics and is also related to the wind direction. The fractions of arsenic are mainly in iron and aluminum hydration oxide binding fractions and residuals, which are not easily uptaken by plants and animals.