外源腐殖酸对黏质农田土壤Cd活性的影响

为探讨外源腐殖酸对黏质农田土壤Cd活性的影响,选取2种典型腐殖酸,采用淋洗技术,通过测定农田土壤总Cd、DTPA-Cd、MgCl₂-Cd的含量,研究了2种腐殖酸及其淋洗时间对土壤Cd活性的影响。研究结果表明:2种腐殖酸处理后,土壤总Cd含量基本不变,土壤DTPA-Cd含量从0.421 mg/kg降低到0.313 mg/kg,MgCl₂-Cd含量从0.2 mg/kg降低到0.169 mg/kg;淋洗时间从1 d增加到5 d,土壤总Cd含量基本不变,土壤DTPA-Cd含量从0.325 mg/kg降低到0.265 mg/kg,MgCl₂-Cd含量从0.196 mg/kg降低到0.165 mg/kg。因此,2种腐殖酸均对黏质农田土壤镉有一定的去除效果。

Influence of Exogenous Humic Acid on Heavy Metal Cd Activity in Clayey Farmland Soil

The effects of two different extrogenous humic acids on the activity of Cd in clayey farmland were examined by measuring the content of total Cd, DTPA-Cd and MgCl₂-Cd after leaching treatment. After two humic acid treatments, the total content of Cd content in the soil remained unchanged in general, the content of DTPA-Cd decreased from 0.421 mg/kg to 0.313 mg/kg, and the content of MgCl₂-Cd declined from 0.2 mg/kg to 0.169 mg/kg. When leaching time increased from 1 day to 5 days, the total content of Cd also remained unchanged overall, DTPA-Cd decreased from 0.325 mg/kg to 0.265 mg/kg, and MgCl₂-Cd reduced from 0.196 mg/kg to 0.165 mg/kg. In conclusion, both the exogenous humic acids could remove Cd in the soil of clayey farmland.