通过模拟试验研究了茭草淹水还田培养过程中土壤溶液Eh、pH值、溶解性有机碳(DOC)和金属离子浓度以及土壤磷形态的动态变化.结果表明,茭草淹水还田可增强土壤的还原作用,提高上覆水和孔隙水中DOC的浓度,从而促进土壤中氧化铁结合态磷的溶解,增加向上覆水中磷的释放.相关分析结果表明,茭草淹水还原过程中Eh和溶液中DOC浓度的变化是引起上覆水磷浓度变化的主要原因.茭草还田前期可显著增加茭白田上覆水中磷的浓度.%In this simulation test for returning the straw of Zizania caduciflora to the waterlogged paddy field, the dynamic changes in the Eh-value, pH-value, dissolved organic carbon ( DOC) concentration and metal ion concentration of soil solution as well as the chemical forms of soil phosphorus were studied. The results showed that returning the straw of Z. caduciflora to the waterlogged paddy field could enhance the reduction of the flooded soil, increase the concentration of DOC in both overlying water and pore water, promote the dissolution of iron-oxide-bound phosphorus in soil, and increase the release of phosphorus from soil to overlying water. The correlation analysis indicated that:during the decomposition of Z. caduciflora straw in the waterlogged pad-dy soil, the variations in Eh-value and DOC concentration of soil solution were the main reasons for the changes in phosphorus concentration of the overlying water. The phosphorus concentration in the overlying water was significantly increased at the earlier stage of returning Z. caduciflora straw to the waterlogged paddy field.
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