Effects of root exclusion on soil respiration in Cinnamomum camphora plantation

Soil respiration was measured with Li-8100 soil CO2 efflux system in Cinnamomum camphora plantation in forest park of Changsha,Hunan,with de-rooting treatments and trenching method,from August 2009 to July 2010.The results show that the soil respiration had a signifi cant seasonal change both in the trenched plots and the control plots.The rates of soil CO2 efflux were about 1.426～5.641 μmol·m-2s-1 in the trenched plots,and 1.137～4.257 μmol·m-2s-1 in the control plots,respectively.The soil respiration rate in the trenched plots exhibited a highly markedly exponential correlation with the soil temperature at 5 cm depth(P =0.000)(without living roots) and a highly markedly quadric relationship with the soil moisture at 5 cm depth(P=0.012).The results indicate that the root system was an important factor affecting soil CO2 efflux,soil temperature and soil moisture in forest.