秸秆还田对吉林黑土区土壤有机碳、氮的影响

Effect of straw returning on soil organic carbon and soil nitrogen in black soil area of Jilin

秸秆是农业生产的重要有机肥来源之一,研究其还田过程中土壤有机碳、氮的变化,对了解土壤质量的改变具有重要意义。2011年5～9月作物生长期间,对黑土区不同秸秆全部还田、秸秆全部还田+化肥(C:N=1:10)、秸秆全部还田+化肥(C:N=1:20)后,土壤有机碳、氮的变化研究结果显示,与秸秆未还田(对照)相比,秸秆全部还田(C1.0)条件下土壤pH与土壤湿度略有降低,其他指标则相应增加;含有秸秆的处理中,土壤有机碳、pH、土壤呼吸强度、土壤温度变化趋势均为C1.0>C/N10>C/N20。土壤呼吸强度、土壤温度、湿度变化随着时间呈下降趋势。主成分分析显示,秸秆还田有利于改善土壤有机碳、全氮以及C/N等。

Straw is an important source of organic fertilizer. Research the changes of the content of soil organic carbon and nitrogen during the straw returning processes.It has an important significance to understand soil quality improvement.During May to September,four types of fertilization were carried out in this study including control （CK）,straw （C10）,straw and nitrogenous fertilizers （C/N10,C/N20）. The results showed that soil pH and moisture in C1.0 were lower than that in control （CK）,but other soil properties were increasing In the treatments of C1.0,C/N10 and C/N20,the changes tendency of soil organic carbon,pH,soil respiration and temperature were C1.0〉C/N10〉C/N20.Soil respiration,soil moisture and temperature were showed a decline from May to September.In the principal component analysis,straw returning on soil could beneficial to improve soil organic carbon,soil total nitrogen,carbon nitrogen ratio and so on.