石灰对铅污染土壤修复效果评价

为了研究铅污染菜地土壤施用石灰对小白菜-土壤生态系统的影响及持续效果，探讨石灰修复铅污染菜地土壤的可行性，采集铅污染菜地土壤开展连续盆栽试验，设置5个石灰用量处理（0、1.5 g/kg、3.0 g/kg、4.5 g/kg、6.0 g/kg）。石灰施入土壤中平衡2周后移栽小白菜，连续种植3茬。同时采集小白菜样本和土壤样本，测定土壤pH、土壤Pb有效态含量和微生物活性等指标，并分别测定小白菜地上和地下部的生物量和铅含量。结果显示：石灰对降低土壤铅有效态和小白菜中铅含量的持效性较差，但施用石灰可增加土壤中的微生物活性，特别是种植小白菜后对增加土壤中微生物活性效果更明显，研究发现对羧酸类和胺类等碳源利用能力强的微生物可增加土壤中铅有效态的含量，对聚合物类、糖类、氨基酸类和其他类碳源利用能力强的微生物可以降低小白菜中的铅含量。研究结果为石灰修复重金属污染土壤的使用提供了更合理的理论支撑。

Remediation Effects Evaluation of Lime on Lead Polluted Soil

Effects of the lime and cabbage application on the lead pollution soil ecosystem and its sustainable effects were studied in this paper to discuss the practicability of remediation of lead pollution soil by lime. A pot experiment was carried out in greenhouse to observe the yield. Five levels of lime additions (0, 1.5 mg/kg, 3.0 mg/kg, 4.5 mg/kg and 6.0 mg/kg soil) were added into the soil in the balance after 2 weeks of transplanting cabbage. Cabbage were continuous planted for three batches. Cabbage samples and soil samples were collected at the same time. The soil pH value, soil available lead content, microbial activity etc. indicators were determined. Cabbage of the biomass and the content of lead were also determined. Results showed that lime had no lasting effect on reducing the soil available lead content and cabbage lead content for the lead pollution vegetable soil. But lime could increase the microbial activity in the lead pollution soil. Especially after planted the cabbage, the activity of microbial was obviously increased. Microbe with strong ability of using carboxylic acids and amine carbon source could increase the content of soil available lead. Microbe with utilization ability for polymers, carbohydrates, amino acids and other types of carbon source could reduce the cabbage lead content. The results was expected to provide more reasonable theoretical support for the remediation heavy metal contaminated soil.