施用铁基生物炭后镉污染稻田土壤有效镉及有机碳的变化

Changes of available cadmium and organic carbon in cadmium contaminated paddy soil through application of iron-based biochar

为了实现镉污染稻田减污固碳的现实需求,以铁基生物炭为研究对象,通过大田试验,采集了土壤和水稻子粒样品,分析了土壤有效镉含量、有机碳含量与子粒镉含量及其相关性。结果表明,与对照相比,铁基生物炭降低了稻田土壤有效镉含量,降幅为11.98%~28.71%;铁基生物炭提高了土壤有机碳含量,增幅为3.66%~12.88%;铁基生物炭降低了水稻子粒镉含量,降幅为4.16%~63.58%。土壤有效镉含量与土壤有机碳含量呈极显著负相关(P<0.01),与水稻子粒镉含量呈极显著正相关(P<0.01)。因此,铁基生物炭有利于实现镉污染稻田降镉固碳。

In order to meet the practical needs of reducing pollution and fixing carbon in cadmium polluted rice fields,iron-based bio-char was selected as the research object.Through field experiments,soil and rice grain samples were collected,and the soil available cadmium contents,organic carbon contents,and rice grain cadmium concentrations and their correlation were analyzed.The results showed that compared to the control,iron-based biochar reduced the effective cadmium content in paddy soil by 11.98%~28.71%,in-creased soil organic carbon content by 3.66%~12.88%,and reduced the cadmium content in rice grains by 4.16%~63.58%.There was a highly significant negative correlation(P<0.01)between soil available cadmium and organic carbon content,and a highly significant positive correlation(P<0.01)between soil available cadmium and rice grain cadmium content.Therefore,iron-based biochar was ben-eficial for achieving cadmium reduction and carbon sequestration in rice fields contaminated with cadmium.