Straw return, as an important agricultural management measure, is receiving growing attention. Hydroxyl radical (^•OH) can be produced when subsurface soil interacts with oxygen, but the effects of straw incorporation on ^•OH formation have rarely been evaluated. In this study, we found that straw return had a significant effect on soil properties. Soil pH and redox potential (Eh) decreased while electronic conductivity (EC) showed an increment. Dissolved organic carbon content of soil initially increased and then decreased to the same level as the control by the end of the experiment of 120 days. Moreover, Fe(II) formation was promoted by straw return under anaerobic conditions. ^•OH was produced in the flooded paddy soil when exposed to oxygen, which correlated well with Fe(II) content. The effect of rape (Brassica campestris L.) straw on ^•OH formation rate was more evident as compared to wheat (Triticum aestivum L.) straw, suggesting a potentially more profound influence of rape straw return on pollutant transformation in paddy soils.

作为一项重要的农业管理措施，秸秆还田正受到越来越多的关注。当地下土壤与氧气相互作用时，会产生羟自由基（^• OH），但很少评估秸秆掺入对^• OH形成的影响。在这项研究中，我们发现秸秆还田对土壤性质有重要影响。土壤pH和氧化还原电位（Eh）降低，而电子电导率（EC）显示增加。在120天实验结束时，土壤中溶解的有机碳含量开始增加，然后下降至与对照相同的水平。此外，在厌氧条件下，秸秆还田可促进Fe（II）的形成。^•暴露在氧气中的水淹稻田中会生成OH，这与Fe（II）含量密切相关。与小麦（Triticum aestivum L.）秸秆相比，油菜（Brassica campestris L.）秸秆对^• OH形成速率的影响更为明显，这表明油菜秸秆还田对稻田土壤污染物转化的影响可能更大。