【摘要】 对四川省成都经济区内3种代表性土壤生长的水稻、小麦、玉米及其根系土进行了硒含量的采样分析。根据成土母质的不同,布置45个不同类型土壤的垂直剖面,采集不同深度(0～200cm)的土壤样品267件。对土壤样品和农作物样品分别以原子荧光法和等离子体质谱法进行了全硒质量分数分析。结果表明:根系土(0～20cm)硒的质量分数为(0.055～19.76)×10-6,平均值为0.34×10-6,高于全国表层土壤硒的质量分数平均值(0.246×10-6)。各种土壤类型中硒均有在表层(0～20cm)土壤中富集的特征。由于成土母质的不同,表层土壤硒质量分数有较大差异:黄壤分布区各类作物根系土硒质量分数平均值最高,其次是水稻土,紫色土最低。根据谭见安等硒生态景观界限值的划分,研究区内主要粮食作物的根系土样品中49.7%属于硒含量适中的,富硒土壤占20.7%;硒不足或者潜在不足的土壤占29.4%。农作物籽实样品中的硒质量分数分析表明:大米样品中有19.9%属于富硒大米,小麦样品中有29.8%属于富硒小麦;但同时存在硒缺乏或潜在缺乏的样品,玉米样品中90%以上缺硒或潜在缺硒。更多还原

【Abstract】 This paper analyzes the selenium contents of three farm crops,paddy rice,wheat and corn,and the relevant soils taken from the root zones in Chengdu economic regions of Sichuan.A total of 267 soil samples were collected from different depths(0~200 cm)in 45 soil profiles according to the different soil parent rocks.The total concentration of selenium is analyzed by AFS and ICP-MS.The results from the three typical soil types show that the selenium concentrations of the root soils are ranged from(0.055~19.76)×10-6,with an average value of 0.34 ×10-6.The average value is higher than the national average level(0.246×10-6)of surface layer soils.Selenium concentrates in the surface layer(0~20 cm)in all soil types.The average concentration of the selenium in the surface layer has a notable difference between the soil parent rocks.The highest selenium concentration in the root zones is found in the loess soil,followed by the paddy soil,and the lowest concentration is found in the purple soil.According to the selenium boundary values of the ecological landscapes demarcated by Tan Jian-an et al.(1991),49.7% of the root soils displays a moderate level of selenium content;20.7% of that belongs to be rich in selenium,and the rest(29.4%)of that exhibits to be deficient or potentially deficient in selenium.The selenium concentrations of the three crops seeds show that 19.9% of the rice samples and 29.8% of the wheat samples belong to the type rich in selenium,while more than 90% of the corn samples display to that deficient or potentially deficient in selenium.更多还原