云南省盈江县旧城-姐冒地区土壤和农产品硒地球化学特征及影响因素

Geochemical characteristics and influencing factors of Selenium in soils and agricultural products in the Jiucheng-Jiemao area, Yingjiang County, Yunnan Province

基于云南省盈江县旧城-姐冒地区土壤、岩石和农产品采样分析资料,研究了土壤硒地球化学特征及主要影响因素,分析了农产品硒含量特征。结果表明,研究区土壤硒含量范围为0.01×10^-6~2.22×10^-6,平均值为0.23×10^-6,其中富硒土壤面积为73.41 km2,占比17.47%;硒主要以残渣态形式存在,而能被农作物有效吸收的水溶态和离子交换态含量仅占总量的3.32%;土壤硒含量主要受成土母质、土壤硅铝铁率、有机质和pH值等因素影响。按照相关评价标准,研究区共有15件咖啡、1件澳洲坚果、2件稻谷和5件甘蔗达到安全富硒食品要求,其安全富硒率分别为100%、10%、1.32%和16.67%,且与富硒土壤集中分布位置基本一致。

Based on the sampling data of soils, rocks and agricultural products in the Jiucheng-Jiemao area, Yingjiang County, Yunnan Province, geochemical characteristics of selenium in soils and main influencing factors were studied, and the characteristics of selenium content in agricultural products were analyzed. The results show that the range of selenium content in soils of the study area is 0.01×10^-6~2.22×10^-6, the average value is 0.23×10^-6 and the area of selenium-rich soil is 73.41 km2, accounting for 17.47%, that selenium is mainly in the form of residue state, but the percentage of water soluble state and ion exchange state which can be effectively absorbed by crops is only 3.32%, and that the content of selenium in soil is mainly influenced by soil-forming parent materials, silica-sesquioxide ratio, organic matter and pH value. According to the relevant evaluation criteria, a total of fifteen coffee beans, one Australian nut, two rice and five sugarcanes can meet the requirements of safe selenium-rich food. The safe selenium-rich rate of four kinds of agricultural products is 100%, 10%, 1.32% and 16.67% respectively, which is basically consistent with the distribution position of selenium-rich soil.