糯高粱红珍珠移除土壤重金属效果及籽粒安全性评价

Effect of Waxy Sorghum Hongzhenzhu on Removing Heavy Metals from Soil and Evaluation of Grain Safety

为解决Cd污染土壤"水改旱"的替代作物选择问题,结合"重金属植物移除及利用示范"项目的实施,进行了替代粮食作物移除土壤重金属试验。结果表明:试验区土壤重金属Cd含量背景值严重超标,Hg、As、Pb和Cr未超标。在中等和偏低肥力的土壤上,糯高粱红珍珠产量分别为4.89和3.24 t/hm^2,移除土壤重金属效果明显,Cd移除总量为38.411 g/hm^2,其中由茎叶移除的占98.5%,显著高于籽粒。籽粒中Cd、Hg、As、Pb、Cr的平均含量分别为0.145、0.008、0.158、0.11、0.772 mg/kg,均低于"GB 2762—2017食品安全国家标准食品中污染物限量"的标准,可安全用作酿酒原料。酒用糯高粱红珍珠可在湘潭地区大力推广种植,在其他Cd污染严重的地区可考虑作为"水改旱"的替代作物。

In order to solve the problem of alternative crop selection for "water to drought" in the Cd contaminated soil,combined with the implementation of "heavy metal plant removal and utilization demonstration" project,the experiment of removing heavy metals from soil by alternative food crops was carried out. The results showed that the background value of soil heavy metal Cd content in the experimental area seriously exceeded the standard,while Hg,As,Pb and Cr did not exceed the standard. In medium and low fertility soil,the yield of waxy sorghum "Hongzhenzhu" was 4.89 t/hm^2 and 3.242 t/hm^2,respectively,and the effect of removing heavy metals from soil was obvious. The total amount of Cd removal was 38.411 g/hm^2,of which 98.5% was removed by stems and leaves,which was significantly higher than that of grains. The average contents of Cd、Hg、As、Pb and Cr in grain were 0.145,0.008,0.158,0.11 and 0.772 mg/kg,respectively,which were lower than the national safety standard(GB 2762—2017),and could be safely used as raw material for winemaking. Glutinous sorghum Hongzhenzhu for wine can be widely cultivated in Xiangtan area,and could be used as a substitute crop for "water to drought" in other areas seriously polluted by Cd.