Variations of soil respiration flux components in a Larix gmelinii plantation during growth season
Meng, C.; Luo, J.; Pang, F.-y.
Ying Yong Sheng Tai Xue Bao 24(8): 2135-2140
2013
ISSN/ISBN: 1001-9332 PMID: 24380330 Document Number: 668998
By using trenching-box method and Li-8150, an observation on the diurnal and monthly variations of soil respiration flux components in a Larix gmelinii plantation in the Harbin Experimental Forest Farm of Northeast Forestry University was conducted in 2010, with the temperature sensitivity of the flux components analyzed. The diurnal variations of the respiration flux of litter, root and mineral soil presented a single peak pattern. From May to October, the diurnal variation amplitudes of the respiration flux of litter, root and mineral soil were 3.1% - 12.4%, 1.9% - 8.7%, and 10.9% - 67.2%, respectively. The mean values of the respiration flux of litter and root occupied 21.2%, 11.1%, 13.4%, 12.0% and 14.2%, and 10.3%, 8.8%, 11.6%, 10.0% and 12.5% of the total, with a small diurnal fluctuation and the mean monthly value being 14. 3% and 10.6%, respectively. The mean value of the respiration flux of mineral soil was 68.5%, 80.2%, 75.1%, 78.1% and 73.3%, also with a small diurnal fluctuation and the mean monthly value being 71.5%. The sensitivity of the respiration flux of litter and mineral soil to the temperature at 10 cm soil depth was significantly higher than that to the temperature at soil surface, and the Q10 value of the respiration flux of mineral soil was higher than that of the respiration flux of litter. No significant difference was observed in the sensitivity of the respiration flux of root to the temperature at soil surface and at 10 cm soil depth. The monthly variation of the Q10 for the respiration flux of litter and root was higher at low temperature and lower at high temperature. On the contrary, the monthly variation of the Q10 for the respiration flux of mineral soil was lower in summer and higher in spring and autumn.