复合改良剂对镉污染土壤中黄瓜品质的影响

以黄瓜（Cucumis sativus L.）为试验材料，种植在人工配置的不同污染程度（2、4 mg/kg CdCl2·2.5H2O）的镉污染盆栽土壤中，研究不同浓度土壤复合改良剂（0、600、900、1200 mg/kg）对土壤有机质、pH、微生物数量、黄瓜果实镉含量和营养品质的影响。结果表明，2、4 mg/kg镉处理土壤施用1200 mg/kg复合改良剂后，土壤有机质含量分别增加了23.17%和32.89%，细菌数量分别增加了87.61%和96.02%，微生物总量分别增加了59.95%和55.81%；施用900 mg/kg复合改良剂对2、4 mg/kg镉处理土壤真菌数量提升作用最明显，增幅分别为137.50%和106.72%；但是施用复合改良剂对土壤 pH无显著影响。施用复合改良剂可明显提高黄瓜果实安全性和营养品质，2、4 mg/kg镉处理土壤种植的黄瓜果实中镉含量分别降低了31.40%和24.35%，维生素 C含量分别增加了25.00%和91.42%，可溶性糖含量分别增加了37.03%和27.06%，可溶性固形物含量分别增加了14.29%和58.80%。说明复合改良剂能够用于重金属镉污染土壤的原位修复，并可显著提高黄瓜果实的品质。

Effects of a Complex Amendment on the Quality of Cucumber Fruit under Cd Contamination Stress

Pot experiments were carried out to investigate the effects of a complex amendment on the soil organic matter content, pH, microbial quantity, Cd uptake and nutritional quality of the fruit of cucumber (Cucumis sativus L.) planted in two levels (CdCl2·2.5H2O mg/kg and 4 mg/kg) of Cd-contaminated soil in which different concentrations of complex amendments (0, 600, 900, 1 200 mg/kg) were added. The results showed that when applying 1 200 mg/kg amendment, the organic mat-ter content, bacterial number and total microorganism amounts in 2 and 4 mg/kg Cd-contaminated soil increased by 23.17% and 32.89%, 87.61% and 96.02%, 59.95% and 55.81%, respectively. When 900 mg/kg amendment was applied, the fungi number in 2 and 4 mg/kg Cd-contaminated soil reached the maximum, in-creasing by 137.50% and 106.72% respectively. However, applying the amendment had no significant effect on the pH of soil. The security and nutritional quality of cu-cumber fruits were obviously improved comparing with control. The Cd content in cucumber fruits decreased by 31.40% and 24.35%, respectively, in 2 and 4 mg/kg Cd-contaminated soil. Furthermore, Vc, soluble sugar and soluble fixation content in cucumber fruits of 2 and 4 mg/kg Cd-contaminated soil went up by 25.00% and 91.42%, 37.03% and 27.06%, 14.29% and 58.80%, respectively. lt was indicated that the complex amendment can obviously improve the quality of cucumber fruit and thus can be used in the in situ_repair of Cd-contaminated soil.