青海地区低镉积累作物品种筛选研究

Screening research on low cadmium accumulating crop varieties in Qinghai Region

中文关键词:  土壤  低镉积累  品种筛选  污染评价

英文关键词:soil  low Cd accumulation  variety screening  contamination evaluation

中文摘要:

      目的 筛选出适合青海地区种植的重金属Cd低积累作物品种并评价其农产品安全性。方法 通过田间实验, 在重金属污染耕地种植青稞、油菜和蚕豆等9种作物, 分析不同作物根部、植株、籽粒及相对应土壤中Cd元素含量。不同作物样品经石墨炉消解后用电感耦合等离子体发射光谱(inductively coupled plasma atomic emission spectrometer, ICP-OES)测定Cd含量。通过富集系数法对作物各组织器官的富集能力进行分析, 利用标靶危险系数法(target hazard quotient, THQ)对作物籽粒Cd元素的非致癌健康风险进行评价。结果 青稞和小麦土壤Cd含量超标, 所有作物籽粒Cd含量符合国家标准; 小麦根部与植株的Cd富集能力均低于其余作物, 作物籽粒对土壤Cd的富集能力最低的是燕麦和小麦; 成人因摄入6种作物可食部位中Cd不存在健康风险, 而儿童因摄入青稞和马铃薯可食部位中Cd存在健康风险。结论 油菜和燕麦是适合当地种植的一种Cd低积累型作物, 可以保证当地农田的安全利用。因此, 本研究可为青海地区筛选低Cd积累的作物品种并将其大规模应用于受污染耕地提供科学依据。

英文摘要:

      Objective To screen the crop varieties with low accumulation of heavy metal Cd suitable for cultivation in Qinghai and evaluate of their agricultural product safety. Methods Through field experiments, 9 crops, including barley, oilseed rape and broad bean, were planted in heavy metal-contaminated arable land in a field trial to analyze the Cd content in the roots, plants, seeds and corresponding soils of different crops. Cd content of different crop samples was measured by inductively coupled plasma atomic emission spectrometer (ICP-OES) after digestion in a graphite furnace. The enrichment capacity of each tissue and organ of the crop was analyzed by the enrichment coefficient method, and the non-carcinogenic health risk of Cd in crop seeds was evaluated by the target hazard quotient (THQ) method. Results The soil Cd content of barley and wheat exceeded the standard, but the seed Cd content of all crops met the national standard; the Cd enrichment capacity of wheat roots and plants was lower than that of the other crops, and the lowest soil Cd enrichment capacity of crop seeds was found in oats and wheat; there was no health risk for adults due to the intake of Cd from the edible parts of the 6 kinds of crops, and there was a health risk for children due to the intake of Cd from the edible parts of barley and potatoes. Conclusion Oilseed rape and oats is a kind of Cd low-accumulating crop suitable for local cultivation, which can ensure the safe utilization of local farmland. Therefore, this study can provide a scientific basis for screening crop varieties with low Cd accumulation and applying them on a large scale to polluted croplands in Qinghai.