铯在土壤-大豆间的迁移和分布特征

Characteristics of transfer and distribution of cesium in soil-soybean system

目的探讨铯(Cs)通过大豆根系吸收,从土壤向大豆迁移及其在大豆各组织器官中的分布特征。方法分别以土壤Cs背景值的1倍(5.37 mg/kg)、2倍(13.78 mg/kg)、10倍(49.64 mg/kg)、15倍(77.14 mg/kg)、20倍(97.26 mg/kg)和25倍(126.30 mg/kg)温室盆栽大豆56 d。采用石墨炉原子吸收光谱(GF-AAS)法检测土壤以及大豆果实、叶、茎和根系中的Cs含量。结果 Cs在大豆的根中含量最高,叶中含量次之,茎和果实中的含量最少并且相当。随土壤中Cs含量的增加,大豆各器官的迁移系数(TF)较稳定。根的富集率(CR)较其他器官高,果实、叶和茎中的CR随着土壤中Cs含量的升高而呈上升的趋势。大豆果实、叶、茎、根中的Cs含量间均呈正相关(P<0.01),同时,土壤与大豆各器官中的Cs含量间也均呈正相关(P<0.05,P<0.01)。结论大豆各器官对Cs有一定蓄积作用。

Objective To study the characteristics of cesium(Cs)absorbed by root,transfered and distributed in soybean[Glycine max(L.)Merr.]organs from soil.Methods The experiment was carried out by soybean pot in greenhouse,Cs with different concentrations was added to the cultivated soil,and soybeans were harvested after 56-day cultivation.The contents of Cs in the cultivated soil were 1-fold(5.37 mg/kg),10-fold(49.64 mg/kg),15-fold(77.14 mg/kg),20-fold(97.26 mg/kg)and 25-fold(126.30 mg/kg)of background value of Cs content in the cultivated soil.The Cs contents of soybean fruit,leaf,stem and root were detected by graphite furnace atomic absorption spectrometry(GF-AAS).Results The content of Cs was the highest in the root of soybean,the second in the leaf,the nexts in stem and fruit which were similar.With the increase of Cs content in soil,the transportation factor(TF)value of soybean plants was stable.The value of concentration ratio(CR)for Cs was higher in roots compared with those in other organs,and increased in fruits,leaves and stems with the increase of Cs content in soil.There was a significantly positive correlation between the contents of Cs in various organs of soybean(P<0.01),as well as between the contents of Cs in soil and organs of soybeans(P<0.05,P<0.01).Conclusion Cesium may accumulate in all organs of soybean.