论文部分内容阅读
以含氮和磷的养分溶液(NH4NO3和KH2PO4)模拟大气氮和磷沉降,对华南地区两种人工林马占相思(Acacia mangium)和尾叶桉(Eucalyptus urophylla)林下群落进行处理,通过静态气箱法色谱法测定土壤CH4通量,以研究外源氮和磷对华南地区人工林土壤CH4通量的影响。结果表明,两种人工林的对照样方下CH4通量均为负值,这说明土壤从大气中吸收CH4,也表明鹤山人工林是大气CH4的汇。增氮和增磷处理都增加了马占相思林的CH4排放通量,即促进了马占相思林CH4的排放过程;在旱季,增氮和增磷处理促进了尾叶桉林土壤CH4的排放,但是,从整个实验期间的观测来看,氮和磷处理对尾叶桉林土壤CH4通量没有显著的影响。
The nitrogen and phosphorus nutrient solutions (NH4NO3 and KH2PO4) were used to simulate the atmospheric nitrogen and phosphorus deposition. Acacia mangium and Eucalyptus urophylla were planted in the understory of two plantations in South China. CH4 flux in soil was determined by air-box chromatography to study the effect of exogenous nitrogen and phosphorus on soil CH4 fluxes in artificial forests in South China. The results showed that CH4 flux was negative in the control plots of both plantations, indicating that the soil absorbs CH4 from the atmosphere, indicating that Heshan artificial forest is the sink of atmospheric CH4. Nitrogen and phosphorus increased the CH4 flux of Acacia mangium, which promoted the emission of CH4 from Acacia mangium. In the dry season, the increase of nitrogen and phosphorus increased the emission of CH4 in soil of Eucalyptus urophylla, From the observations during the entire experiment period, nitrogen and phosphorus treatments had no significant effect on soil CH4 flux in Eucalyptus urophylla.