Cao Kun-Kun, Li Cheng-Cheng, Hu Xue-Yu, Guo Xiao, Huang Yang
School of Environmental Studies, China University of Geosciences, Wuhan 430078, China.
Huan Jing Ke Xue. 2020 Jul 8;41(7):3434-3440. doi: 10.13227/j.hjkx.202001098.
To explore the safe utilization of technology in mildly and moderately cadmium (Cd)-contaminated farmland and realize the safe production of agricultural products, two different cadmium-accumulating genotypes of Tsai-tai were used as test crops, using the pot experiment method. The same six treatments were set on the soil where the two test crops were planted:control (CK), addition of 3% (mass fraction) biochar (BC), addition of 0.17% calcium magnesium phosphate fertilizers (CMP), foliar application of 3 mg·L NaSeO aqueous solution (Se), BC+Se, and CMP+Se, to study the changes in available cadmium in soil under different treatments and the characteristics of cadmium accumulation in different parts of the plant. The results showed that:① Under the same treatment, the content of available cadmium in soil near the root of the low-cadmium-accumulating genotype of Tsai-tai of Jinqiuhong Ⅲ was significantly lower than that of the high-cadmium-accumulating genotype of Shiyuehong. BC and CMP had a significant passivating effect on cadmium in the soil near the root of Jinqiuhong Ⅲ, and the passivating effect of BC was better than that of CMP; the effect of passivating treatment was significantly better than that of foliar application of selenium. ② The root system of Tsai-tai of Jinqiuhong Ⅲ had a stronger ability to accumulate cadmium than that of Shiyuehong, and the accumulated cadmium tended to be stored in the root. There were no synergistic effects between the foliar application of selenium and the two kinds of passivants on inhibiting the transfer and enrichment of cadmium to the edible parts of Tsai-tai. ③ Under the treatments of BC and CMP, the content of cadmium in the edible part of Tsai-tai of Jinqiuhong Ⅲ was lower than the limit value of cadmium in GB 2762-2017 (0.10 mg·kg). This study shows that for mildly and moderately cadmium-contaminated farmland, applying green passivants such as biochar, calcium magnesium phosphate fertilizers, and planting crops with weak absorption and low accumulation can achieve the safe use of the cadmium-contaminated farmland and safe production of agricultural products.
为探索镉（Cd）轻度和中度污染农田中技术的安全利用并实现农产品安全生产，采用盆栽试验法，选用两种不同镉积累基因型的菜苔作为试验作物。在两种试验作物种植的土壤上设置相同的六个处理：对照（CK）、添加3%（质量分数）生物炭（BC）、添加0.17%钙镁磷肥（CMP）、叶面喷施3 mg·L 亚硒酸钠水溶液（Se）、BC+Se和CMP+Se，研究不同处理下土壤有效镉的变化及植株不同部位镉的积累特征。结果表明：①在相同处理下，金秋红Ⅲ菜苔低镉积累基因型根部附近土壤中有效镉含量显著低于十月红高镉积累基因型。BC和CMP对金秋红Ⅲ根部附近土壤中的镉有显著钝化作用，且BC的钝化效果优于CMP；钝化处理效果显著优于叶面喷施硒。②金秋红Ⅲ菜苔根系积累镉的能力比十月红强，且积累的镉倾向于储存在根部。叶面喷施硒与两种钝化剂在抑制镉向菜苔可食用部位转移和富集方面没有协同作用。③在BC和CMP处理下，金秋红Ⅲ菜苔可食用部位镉含量低于GB 2762-2017中镉的限量值（0.10 mg·kg）。本研究表明，对于镉轻度和中度污染农田，施用生物炭、钙镁磷肥等绿色钝化剂并种植吸收弱、积累低的作物，可实现镉污染农田的安全利用和农产品安全生产。
