生物炭对农田土壤中重金属的修复效应分析

Analysis of remediation effects of biochar on heavy metals in farmland soils

文章简述了我国农田土壤重金属累积现状,并详细分析了生物炭对农田土壤中重金属的修复机制和效应,提出生物炭不仅比表面积大,且具较高的离子交换量,含有羧基、酚基、羟基、醌类物质等丰富的含氧官能团,降低土壤中重金属有效性;同时生物炭还可以提高土壤中pH,进而影响重金属的活性,达到钝化重金属的目的。且施用生物炭同时可提高种子萌发、植物生长、作物产量,优化土壤微生物活性和种群结构。最后对生物炭的实际应用等方面提出展望。

In this paper,the accumulation status of heavy metals in farmland soil in China is briefly described,and the remediation mechanism and effects of biochar on heavy metals in farmland soil are analyzed in detail.It is pointed out that biochar not only has large specific surface area,but also has a high ion exchange capacity and contains rich oxygen-containing functional groups such as carboxyl groups,phenol groups,hydroxyl groups and quinone substances,which reduce the bioavailability of heavy metals in soil.At the same time,biochar can also increase the pH of the soil,thus affecting the activity of heavy metals and achieving the purpose of passivation of heavy metals.Furthermore,the application of biochar can improve seed germination,plant growth,crop yield,optimize soil microbial activity,and population structure.Finally,prospects for the practical application of biochar are discussed.