连续施用有机肥对菜田土壤Cu和Zn积累及辣椒产量品质的影响

采用田间随机区组试验,研究了不同用量鸡粪和猪粪有机肥(0,15,30,45和60 t/hm^2)施用后,重金属Cu和Zn在土壤剖面迁移积累特征,及辣椒产量、品质和各器官(根、茎、叶和果实)Cu和Zn含量的变化。结果表明,鸡粪和猪粪施用显著增加了耕层(0—20 cm)土壤Cu和Zn含量,与对照相比,Cu含量增幅分别达到22.60%~66.59%和36.13%~95.00%,Zn含量增幅分别达到10.49%~39.27%和11.18%~51.94%,猪粪施用后耕层(0—20 cm)土壤Cu和Zn含量增幅大于鸡粪;鸡粪和猪粪带入的Cu和Zn主要积累在耕层(0—20 cm)土壤,Cu和Zn含量最高分别为36.95,137.24 mg/kg,尚未超出国家安全标准。高用量(60 t/hm^2)鸡粪和猪粪中的Cu和Zn存在明显向土壤深层迁移现象,与猪粪处理相比,鸡粪中带入的Cu和Zn向下迁移的幅度小。鸡粪和猪粪施用显著提高了辣椒果实单果重及产量,在施用量为30 t/hm^2时达到最大,产量比对照分别增加24.98%和29.04%,高用量(60 t/hm^2)鸡粪和猪粪显著提高了辣椒Vc含量、蛋白质含量和可溶性糖含量,降低了硝酸盐含量,改善了辣椒品质。15 t/hm^2鸡粪和60 t/hm^2猪粪显著提高了辣椒果实Cu含量,但均未超过20 mg/kg,可以安全食用。鸡粪和猪粪的施用对果实Zn含量(16.35~20.87 mg/kg)影响不显著。可以认为,合理施用鸡粪和猪粪有机肥在短期内能够改善土壤性质,提高作物产量和品质,虽然会造成Cu和Zn在耕层(0—20 cm)土壤的积累,但尚未引起土壤Cu和Zn污染,也不影响辣椒果实的安全食用,但如果长期施用则有必要进行进一步监测。

Effects of Continuous Application of Organic Fertilizer on Cu and Zn Accumulation in Soil and the Yield and Quality of Pepper (Capsicum Annuum L.)

Based on the randomized block test with different amount of chicken manure and pig manure application (0, 15, 30, 45 and 60 t/hm²), the characteristics of accumulation and migration of Cu and Zn in soil profile, the changes in yield, quality, and the content of Cu and Zn in different organs of pepper (roots, stems, leaves, and fruits) were studied. The results showed that the content of Cu and Zn was significantly increased in the tillage layer (0-20 cm) after chicken and pig manure application. Compared to CK, the increase of Cu content reached 22.60%~66.59% and 36.13%~95.00% respectively, and the increase of Zn content reached 10.49%~39.27% and 11.18%~51.94% respectively. The increase of soil Cu and Zn content in the tillage layer (0-20 cm) after application of pig manure was greater than that of chicken manure. The content of Cu and Zn in chicken and pig manure were mainly accumulated in the soil tillage layer (0-20 cm). The highest content of Cu and Zn was 36.95 mg/kg and 137.24 mg/kg, which did not exceed the national safety level. The migration of Cu and Zn to deeper soil was significantly after 60 t/hm² chicken and pig manure application. The downward migration of Cu and Zn in chicken manure was smaller than pig manure treatment. The single fruit weight and yield of pepper significantly increased after chicken and pig manure application, and reached the highest at the 30 t/hm² application, the yield increased 24.98% and 29.04% compared to CK. The Vc content, the soluble sugar content, and the soluble protein content significantly increased, but the nitrate content significantly decreased after high amount of chicken and pig manure (60 t/hm²) application. Application of 15 t/hm² chicken manure and 60 t/hm² pig manure significantly increased Cu content in pepper fruits, but the Cu content did not exceed 20 mg/kg, which was a safe level for eating. The application of chicken and pig manure had no significant effect on the content of Zn in the fruits (from 16.35 to 20.87 mg/kg). It can be concluded that rational application of chicken and pig manure can improve soil properties, increase crop yield and quality in a short term. Although chicken and pig manure application can cause the accumulation of Cu and Zn in the tillage layer (0-20 cm), it has not caused soil pollution of Cu and Zn, and affect the safety of pepper fruits, while further monitoring is necessary if long-term application.