原子荧光光谱法对果园土壤中砷和汞空间分布特征的研究

Using Atomic Fluorescence Spectrometry to Study the Spatial Distribution of As and Hg in Orchard Soils

利用王水消解-双道原子荧光光谱法测定了山东省苹果主产区栖霞市果园土壤中的 As和 Hg含量，验证了检测方法的检出限、准确度与精密度，分析了栖霞市果园土壤中重金属As和 Hg的空间分布特征，并对栖霞市果园土壤中As和Hg的污染状况进行评价。结果表明：栖霞市果园土壤中As的含量范围为2.79～20.93 mg ＆#183; kg -1，平均值为10.59 mg ＆#183; kg -1，而Hg的含量范围为0.01～0.79 mg ＆#183; kg -1，平均值为0.12 mg ＆#183; kg -1。As元素在土壤中变异较小，而 Hg元素在土壤中变异较大。频数分布图显示，土壤中 As元素含量基本符合正态分布，含量大多在7～15 mg ＆#183; kg -1之间，土壤中Hg元素含量不符合正态分布，含量大多在0.03～0.21 mg ＆#183; kg -1之间。土壤As和 Hg含量与土壤各养分指标之间的相关性均不显著，且土壤中As和Hg两种元素之间亦无显著的相关关系。以国家绿色食品产地环境质量标准为评价依据，栖霞市果园土壤A s含量处于无污染的清洁水平，而土壤 H g的污染指数大于1的样点占总数的4.76％，需要引起管理者的注意。

Aqua regia digestion ,double channels-atomic fluorescence spectrometry method was used to determine the concentra-tions of As and Hg in orchard soils of Qixia City -the main apple production area of Shandong province .Validate The detection limitation ,accuracy and precision of the method were validated ,the spatial distribution was analyzed ,and the characteristics of As and Hg pollution in Qixia orchard soils were assessed .The results showed that the range of As concentration in Qixia soils is between 2.79 and 20.93 mg ＆#183; kg -1 ,the average concentration is 10.59 mg ＆#183; kg -1 ,the range of Hg concentration in Qixia soil is between 0.01 and 0.79 mg ＆#183; kg -1 ,the average concentration is 0.12 mg ＆#183; kg -1 .The variation of As concentration in soils is small ,whereas that of Hg concentration is large .Frequency distribution graphics of As and Hg showed that the concentration of As in soils is according with the normal distribution approximately and the concentrations are mostly between 7 and 15 mg ＆#183; kg -1 ,the concentration of Hg in soil isn＆#39;t according with the normal distribution and the concentrations are mostly between 0.03 and 0.21 mg ＆#183; kg -1 .The correlations between the concentrations of As or Hg in soils and the nutrient are not significant and there is no significant correlation even between As and Hg .Based on the environmental technical terms for green food production area ,the As concentration in orchard soil of Qixia City is at clean level ,but there are 4.76% of sample points with Hg pollution index exceeding 1 ,and this should be attracted the attention of the administrators .