秸秆还田对土壤氨氮热力学吸附性质的影响研究

发布时间：2018-04-18 20:14

本文选题：秸秆还田 + 氨氮　；参考：《南京大学学报(自然科学)》2016年01期

【摘要】：通过对比未添加秸秆和添加秸秆情景下潮土和砂姜黑土对氨氮的等温吸附实验,探讨秸秆还田对土壤氨氮热力学吸附性质的影响,为氮素在土壤垂向迁移转化过程中发生的吸附反应提供科学参考.研究表明:1砂姜黑土对氨氮的吸附能力要强于潮土,吸附能力主要与土壤的黏粒含量有关.2在实验设定的浓度范围内,未添加秸秆和添加秸秆的所有样品的吸附等温线均能用Henry吸附等温模型和Freundlich吸附等温模型拟合.同时,Langmuir吸附等温模型可以更好地拟合未添加秸秆以及少量添加秸秆的样品.3添加秸秆的混合样品相对于土壤样品降低了对氨氮的吸附效率和吸附容量.未添加秸秆的土样对氨氮的吸附效率KH的平均值为41.88L·kg-1,饱和吸附量qm的平均值为823.85 mg·kg-1;少量添加秸秆的混合样对氨氮吸附效率KH的平均值为21.29L·kg-1,饱和吸附量qm平均值为732.06 mg·kg-1;大量添加秸秆的混合样对氨氮的吸附效率平均值为13.99L·kg-1.
[Abstract]:The effect of straw returning to soil on the thermodynamic adsorption of ammonia nitrogen was studied by comparing the isothermal adsorption of ammonia nitrogen between the soil and shajiang black soil under the condition of no straw and adding straw.It provides a scientific reference for the adsorption reaction of nitrogen in the process of soil vertical migration and transformation.The results showed that the adsorption of ammonia nitrogen on the black soil of W1 was stronger than that on the aquic soil, and the adsorption capacity was mainly related to the clay content of the soil in the range of concentration set in the experiment.The adsorption isotherms of all samples without and without straw can be fitted by Henry adsorption isotherm model and Freundlich adsorption isotherm model.At the same time, the Langmuir adsorption isotherm model can better fit the adsorption efficiency and adsorption capacity of the mixed sample. 3. The mixed sample with no straw and a small amount of straw can reduce the adsorption efficiency and adsorption capacity of ammonia nitrogen compared with the soil sample.The average adsorption efficiency (KH) of ammonia nitrogen and saturated adsorption capacity (QM) were 41.88L / kg ~ (-1) and 823.85 mg / kg ~ (-1) for soil samples without straw, and 21.29L / kg ~ (-1) for ammonia nitrogen and 21.29L / kg ~ (-1) for saturated adsorption capacity, respectively.732.06 mg 路kg ~ (-1), and the average adsorption efficiency of ammonia nitrogen was 13.99 L 路kg ~ (-1) for mixed samples with a large amount of straw.
【作者单位】：南京大学表生地球化学教育部重点实验室;南京大学地球科学与工程学院;中国科学院地球化学研究所环境地球化学国家重点实验室;
【基金】：国家自然科学基金重点项目(41230640) 国家水体污染控制与治理科技重大专项(2012ZX07204-003)
【分类号】：S141.4;O647.3

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