北亚热带落叶阔叶林土壤呼吸时间变化特征

摘要

利用LI⁃8100开路式土壤碳通量系统测定龙王山森林土壤呼吸速率，研究北亚热带落叶阔叶林土壤呼吸速率的日变化和季节性变化规律．结果表明：北亚热带落叶阔叶林土壤呼吸速率在12—14时达到最大，与土壤温度变化基本一致；森林土壤呼吸速率随土壤温度的季节性变化而变化，在夏季土壤呼吸速率较高，在冬季土壤呼吸速率较低；土壤呼吸速率与土壤温度间存在着明显的指数关系，土壤呼吸温度敏感系数Q10为2�81．%To investigate the diurnal variation and seasonal variation characteristics of soil respiration rate in north subtropical deciduous broad⁃leaved forest,the soil respiration rates in Longwang Mountain forest of Nanjing,Jiangsu province were measured using LI⁃8100 automated soil CO2 flux system,and the soil temperature and moisture were recorded at the same time.The result showed that soil respiration rate increased and reached its peak during 12:00 to 14:00,which is generally in accordance with the diurnal change of soil temperature.As for the seasonal variation, the forest soil respiration rate changed with the seasonal variation of soil temperature. The soil respiration rate was relatively high when the soil temperature was high in summer,and vice versa.Significant relationship was found be⁃tween soil respiration rate and soil temperature, and the Q10 of deciduous broad⁃leaved forest soil in Longwang Mountain was calculated to be 2�81.