锥栗林土壤呼吸动态变化与主要影响因子分析

通过LI-6400对闽北锥栗林的土壤呼吸进行测定与分析。结果表明,不同季节土壤温度的变化较为一致,呈单峰变化趋势,最大值出现在15:00;土壤呼吸速率昼夜变化趋势大致呈单峰变化,不同季节里呼吸速率最大值出现的时间不同,春季与冬季最高值出现在13:00,而夏季与秋季分别出现在17:00与15:00;不同季节土壤呼吸速率的日变化幅度以冬季较小,春季最大;土壤呼吸Q10值的季节变化中,冬季Q10值最大,夏季最小,Q10值随土壤温度的增高而降低。

Analysis of the dynamics of soil respiration of Castanea henryi plantation and its major factors

The dynamics of soil respiration of Castanea henryi economy plantation in the north Fujian Province was measured using Li-6400.Results showed that the maximums of soil temperature at 5 cm depth were commonly observed at around 15:00 in different seasons.The maximal rate of soil respiration occurred at 13:00 in spring and winter,but in summer and autumn were 17:00 and 15:00,respectively.Diurnal variations in soil respiration were mostly correlated to that in soil temperature.There was a significantly exponential relationship between soil respiration and soil temperatures at 5 cm depth during the year and each seasons.The maximal soil respiration rate was 4.54 μmol·m-2·s-1 in summer and the minimum was 1.82 μmol·m-2·s-1 in winter.The Q10 values of soil respiration were the highest in winter,and the lowest in summer,respectively,Q10 value declined with the increasing in temperature.