三种蔬菜对土壤中Sr元素富集和转移特性的研究

Absorption and transport characteristics of strontium onto three kinds of vegetables grown in the soil

目的 探索放射性核素90Sr在土壤-植物系统中的转移特性,并初步分析植物不同组织对土壤中不同浓度Sr的吸收积累特征.方法 利用稳定性核素88Sr替代放射性核素90 Sr进行室内盆栽种植小白菜、芹菜和萝卜的实验.采用电感耦合等离子体发射光谱法（ICP-AES）测定上述3种蔬菜和土壤中Sr的浓度,并计算上述3种蔬菜根部及茎叶部对Sr的转运系数（TF）及富集率（CR）,进而研究Sr在土壤-植物系统中的转移特征.结果 土壤中Sr浓度对于蔬菜的不同组织具有显著影响（F =5.90 ～ 139.39,P＜0.05）.在398.33、477.99和557.57 mg/kg的土壤Sr浓度条件下,小白菜、芹菜和萝卜不同组织Sr浓度均高于对照组（t=-10.49～7.41,P＜0.05）.除了芹菜茎部之外,3种蔬菜的其他组织与实验土壤中Sr含量呈正相关关系（r=0.88 ～0.99,t =7.41 ～15.96,P ＜0.05）.小白菜和萝卜各组织样本的转运系数（基于干重）＞1,且小白菜和萝卜中的富集率表现为：茎叶部＞根部（F=8.22、91.49,P＜0.05）.结论 3种蔬菜对Sr均有一定的富集作用.

Objective To explore the transport properties of the radionuclide strontium 90Sr in the soil-plant system,and discuss the accumulation characteristics of strontiumes in different vegetable tissues.Methods Three kinds of vegetables,including Chinese cabbage,radish and celery,were planted in this experiments using stable nuclide 88Sr instead of 90Sr.Strontium concentrations in these kinds of plant and soil were measured with inductively coupled plasma atomic emission spectrometry （ICP-AES）,and the transportation factor （TF） of strontium and the concentration ratio （CR） of these plants were calculated.Results The contents of strontium in different tissues of the vegetables increased significantly in response to the strontium concentrations in soil （F =3.75-139.39,P 〈 0.05）.The contents of strontium at 398.33,477.99 and 557.57 mg/kg in different tissues of these vegetables were significantly higher than that in control group （t =-10.49-7.41,P 〈0.05）.Except celery stems,there was a positive correlation about contents of the strontium between other tissues of these vegetables and their experimental soils （r =0.88-0.99,t =7.41-15.96,P 〈0.05）.Based on dry weight of examples,the TF in each tissue sample of cabbage and radish was higher than 1,and the concentration ratio,for cabbage and radish,was higher in stems than in roots （F =8.22,91.49,P 〈 0.05）.Conclusions Three kinds of vegetables have been shown to have strontium accumulation ability in soil environment.