天津市主要栽种水稻品种对镉的累积差异研究

Study on the differences in the accumulated characteristics of cadmium in mainly planted rice of Tianjin

中文关键词:  天津市  水稻  镉  累积特性  预测模型

英文关键词:Tianjin  rice  cadmium  absorption and accumulation  prediction model

中文摘要:

      目的 研究天津本地主栽品种水稻对镉的累积特性差异。方法 选取天津市水稻品种津原47, 津原11及津原E28在不同镉添加浓度的盆栽土壤中进行种植, 待成熟后采收地上部分并测定镉含量。结果 各品种籽粒重量及生物量随镉添加浓度升高而降低。水稻的茎叶、稻壳及糙米镉含量则随镉添加浓度升高而升高, 且符合茎叶>稻壳>糙米的规律。各部位富集系数: 津原47为1.56~6.99, 津原11为1.20~7.37, 津原E28为1.11~13.0。根据实验数据建立了3个水稻品种糙米镉含量预测模型, 并计算出安全临界值, 分别是12.20、11.01及12.65 mg/kg。结论 通过比较产量及富集系数表明品种间及水稻各部位对镉的累积特性存在差异。当土壤中的污染浓度超过该临界值时, 糙米中镉含量有可能超出安全限量标准, 存在风险。

英文摘要:

      Objective To study the difference of cadmium accumulation characteristics of Tianjin main rice varieties. Methods Rice varieties of Tianjin Jinyuan 47, Jinyuan 11 and Jinyuan E28 were planted in potting soil with different cadmium concentrations. After maturity, the above-ground parts were harvested and the cadmium content was determined. Results The weight and biomass of all varieties of grain decreased with the increase of adding concentration of cadmium. The contents of cadmium in stem, leaf, rice husk and brown rice increased with the increase of cadmium concentration. Furthermore, the rules of accumulation of cadmium were the concentration of cadmium in stem and leaf was higher than that in rice husk, and that in brown rice was lowest. The enrichment coefficient in different parts were 1.56–6.99 for Jinyuan 47, 1.20–7.37 for Jinyuan 11, and 1.11–13.0 for Jinyuan E28. The models of cadmium content in brown rice for three rice varieties were established according to the experimental data, through that the safety critical values were calculated as follow: 12.20, 11.01, 12.65 mg/kg, respectively. Conclusion By comparison of the yields and enrichment factors, it can be found that there are differences of accumulated characteristics of cadmium in different rice varieties and different parts of rice. When the polluted concentration exceeds the safety critical value, the contents of cadmium in brown rice will probably exceed the Safety Limitation Standard, which has risks.