以福建省漳州尾巨桉（ Eucalyptus urophylla × E. grandis）人工林为研究对象，研究物理去除灌草和施用除草剂2种灌草管理方式对尾巨桉人工林土壤CO2排放和凋落物分解的影响。实验时间为2012年12月至2014年11月，采用LI-COR 8100系统测定土壤呼吸，用分解袋法开展分解实验。结果表明，物理去除灌草方式下土壤温度显著升高，但土壤CO2排放降低；施用除草剂对土壤温度和土壤CO2排放无明显影响。土壤呼吸有明显的季节变化，在雨季较高，在旱季则明显降低。土壤呼吸的温度敏感系数Q10表现为去除灌草（2.49）＞对照（2.38）＞施用除草剂（2.15）。研究表明不同的灌草管理方式对人工林土壤碳循环影响有差异，物理去除对土壤碳排放和物质循环的效应大于施用除草剂。%The artificial forest of Eucalyptus urophylla × E. grandis in Zhangzhou,Fujiang Province is taken as the sample to research the effects of different managements strategies for understory plants on soil respiration and litter decomposition. The object of this paper was to examine the difference of effects of physical removal and herbicide application on soil CO2 emissions and litter decomposition in a Eucalyptus urophylla × E. grandis plantation. The experiment was conducted between December 2012 and November 2014 with LI-COR 8100,which was a randomized design with three treatments including control,physical removal and herbicide application. The experiment results suggest that CO2 fluxes stayed at a relatively high level during the rainy season( April-September ) and a lower level in the dry season( October-March). Physical removal significantly increased the soil temperature and reduced the soil CO2 emission, while herbicide application had no obvious effect. The Q10 values were 2. 49,2. 38,and 2. 15 for the phys-ical removal,control and herbicide application,respectively. Our findings indicate that soil carbon cycling would be influenced by varied understory management strategies,and the physical removal effects on soil carbon emission and element cycling are larger than that of herbicide application.
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