氮沉降对林带土壤N_2O和CH_4通量的影响

Effects of simulated nitrogen deposition on N_2O and CH_4 fluxes of soil in forest belt

于2008年4月～2009年10月在龙王山对林带土壤进行模拟氮沉降试验,采用静态箱-气相色谱法测定土壤N2O和CH4通量,研究氮沉降增加对土壤N2O和CH4排放(吸收)的影响.结果表明,短期内,氮沉降没改变土壤N2O和CH4通量的季节性变化规律和日变化规律.与对照(CK)相比,短期的低氮[50 kg N/(hm2.a),TL]、中氮[100kgN/(hm2.a),TM]和高氮[150kgN/(hm2.a),TH]处理对土壤的N2O和CH4年平均通量和日平均通量都没有显著影响.

To investigate the effects of elevated nitrogen deposition on forest soil N2O and CH4 fluxes,a simulated nitrogen deposition field experiment was conducted in forest belt from April 2008 to October 2009.Nitrogen treatments included the control（no N addition,CK）,low-N [50kgN/（hm2？a）,TL],medium-N [100kgN/（hm2？a）,TM],and high-N [150kg N/（hm2？a）,TH].N2O and CH4 fluxes were measured by a static chamber-gas chromatograph method.Nitrogen deposition did not change the seasonal and daily variation patterns of soil N2O and CH4 fluxes.Compared to the control,TL,TM and TH treatments had no significant effects on annual average and daily average fluxes of N2O and CH4 in soil.Short-term nitrogen deposition did not alter N2O emission fluxes and CH4 absorb fluxes of soil in forest belt.