用两室根箱系统法对土壤氮素转化的空间变异及N_2O的产生之初探

Use the Method of Root Chamber System with Two Compartments to Study Spatial Variability of Soil nitrogen Transformation and N_2O Production

用特制的带有9根采气管的两室根箱系统,采集和分析根箱中9个不同部位土壤空气中N2O的浓度,结合使用具有选择性的硝化抑制剂(包括低浓度的C2H2和DCD),研究在不同铵态氮水平下的硝化过程及其对N2O气体释放的贡献;结合使用高浓度的C2H2,抑制反硝化过程中N2O到N2的还原,研究在不同铵态氮水平下的反硝化过程及其对N2O气体释放的贡献。同时还研究铵态氮、硝态氮转化及其释放N2O气体的时间和空间变异性和植物对它们的影响。结果表明,根箱系统结合使用抑制剂的方法,是一种研究土壤氮素转化过程、N2O气体释放及植物对前两者影响的有效方法。

In this paper, a specially made root chamber system with two compartments and nine gas collection pipes was used to collect the N20 in soil air of nine different spatial position in the root chamber. The following treatments were also used： （1） Two selective nitrification inhibitors, C2H2 and DCD in low concentration were used to study the nitrification process under different NH4^＋-N levels and its contribution to N2O release. （2） High concentration C2H2, which inhibitates the reduction from N2O to N2 in the denitrification process, was used to determine the denitrification process under different NO3^--N levels and its contribution to N2O release. The root chamber system combined with the use of inhibitors was an effective method to study nitrogen transform processes in soil, N2O release process ang the effect of plants on it.