棉秆炭对镉污染土壤的修复效果

Remediation effects of cotton stalk carbon on Cadmium(Cd) contaminated soil

采用盆栽方法,研究了棉秆炭对镉污染土壤的修复效果及对镉污染土壤上小白菜(Brassica chinensis)镉吸收的影响。结果表明:以微孔为主的棉秆炭能够通过吸附或共沉淀作用降低土壤中镉的生物有效性。在轻度镉污染时,棉秆炭处理土壤对镉的吸附速率较快,随着镉污染程度的增加,吸附速率逐渐减慢,吸附量逐渐增加。棉秆炭能够明显降低镉污染土壤上小白菜可食部和根部的镉积累量,可食部镉质量分数降低49.43%～68.29%,根部降低64.14%～77.66%,说明棉秆炭具有修复土壤镉污染,降低蔬菜镉含量的作用,可提高蔬菜品质。

The remediation effects of cotton stalk carbon on Cd contaminated soil and the influence of cotton stalk carbon on the uptake of Cd of Brassica chinensis in Cd contaminated soil were studied by pot experiment. The results showed that bioavailability of Cd were depressed for the adsorption and co-precipitation by cotton stalk carbon which was abundant in the distribution of microspores. The absorption rate of soil treated with cotton stalk on cadmium was faster in light of cadmium pollution, absorption rate decreased and absorption capacity increased with the increasing of cadmium pollution. The accumulation of cadmium in edible part and the roots of Brassica chinensis were reduced significantly by cotton stalk carbon, cadmium content of edible part and roots were reduced by 49.43%-68.29 %, 64.14%-77.66 % respectively. Cotton stalk carbon could renovate Cd contaminated soil and reduce the cadmium content of vegetables, so improve the quality of vegetables.