秸秆还田添加氮素调节碳氮比的研究

施用作物秸秆，常因碳氮比较宽，引起土壤微生物与作物苗期争夺土壤中无机氮的矛盾。本文采用盆栽试验方法，秸秆还田添加不同量的氮素，以冬小麦的产量、株高、分蘖数、叶片中叶　　　绿素含量以及植株对氮、磷、钾的吸收量为指标，找出适宜的碳氮比。结果表明，在冬小麦的各项　指标中，不同处理呈现Ｓ＋Ｎ３＞Ｓ＋Ｎ２＞Ｋ＞Ｓ＋Ｎ１＞Ｓ的规律，添加的氮量以碳氮比为２５：１为宜。

Study on Adjustment of the Ratio of C to N by Adding N During Straw Turnover

Staw turnover usually raised a problem of competition inorganic N between soil microbes and young erops due to the wider ratio of C:N,Pot experiment was conducted in this investigation. Straw was retuned into the soil with different levels of N applied. In order to find out the reasonable ratio of C:N in wheat,the indexes were chosen as fallows: the seed production, plant height, tillered numbers, chlorophyll content in the leaves of winter wheat and the assimulation amount of N,P and K. Result from the different treat' ments in which each above index is considered showed the uniform law :S+N3>N2>S+ N2>CK>S+N1>S, and the appropriate ratio of C:N was about 25: 1 terms of the N application.