中国土壤模式-作物系统重金属生物富集模型建立

Establishment of Heavy Metal Bioaccumulation Model of Soil Pattern-Crop System in China

针对土壤模式建立土壤和作物重金属含量关系模型,旨在消除土壤属性对作物重金属吸收量的影响。当作物类型或品种确定后,作物重金属吸收量只与土壤重金属含量有关。提出了农田作物重金属生物富集的"土壤重金属含量-作物特性-土壤属性"关系理论,定义了土壤模式、土壤模式-作物系统重金属生物富集模型、土壤模式-作物系统重金属生物富集模型图谱等概念,确定了土壤模式的划分方法和使用方法,在此基础上以最近30年来中文期刊发表的土壤镉含量与水稻和小麦镉含量关系作为案例验证了以上方法。结果表明:水稻和小麦同一部位镉吸收量随土壤镉含量增加而增加,水稻和小麦吸收镉能力顺序为根>茎>叶>籽粒,水稻和小麦籽粒镉吸收量在同一范围内。

A relational model of the content of heavy metals between soil and crop in farm system was established based on the different soil patterns to eliminate the effect of soil properties on heavy metal absorption by crop from soils. Thus heavy metals absorption by crops was only related to the contents of heavy metals in soil patterns when crop type or variety was confined. A theory was put forward about bioaccumulation of heavy metals dependent on the relations among heavy metal contents in soil, crop characteristics and soil properties. The concepts of soil pattern, soil pattern- crop system heavy metal bioaccumulation model and its atlas were also defined. Methods for classifying and utilizing soil patterns were established and verified based on the Chinese articles published in the last 30 years dealing with the relationships between Cd contents in farm soils and in rice and wheat plants. The results showed that the Cd absorption quantity in the same plant organ was increasing with Cd content in soil, with Cd absorption ability of root >stem >leaf >grain. The Cd content of rice grains and wheat grains was within the same range.