摘要
利用LI-8100开路式土壤碳通量测量系统，对京西百花山区6种植物群落夏季土壤呼吸作用的昼夜变化进行了对比研究。结果表明，6种植物群落土壤呼吸速率日变化成明显的单峰曲线，高峰值一般出现在13：00～16：00之间，最低值出现在03：30～07：30之间；不同植物群落土壤表层凋落物呼吸对土壤呼吸的贡献率在6．62％～40．83％之间；土壤CO2日释放量以野艾蒿群落最高，其值为254880μmol·m^-2·d^-1，刺槐群落最低，其值为190944μmol·m^-2·d^-1；凋落物CO2日释放量油松群落最大，达91368μmol·m^-2·d^-1，对土壤呼吸的贡献率为40．83％，而杂类草群落最低，日释放量只有13608μmol·m^-2·d^-1，对土壤呼吸的贡献率仅为6．62％。相关分析表明，土壤表层凋落物呼吸速率与凋落物厚度、蓄积量成正相关关系（n=6，P＜0．05），而与凋落物有机质含量无明显的相关性；土壤呼吸速率与环境因子具有显著的相关性，其中与土壤表层（5cm）温度呈极显著正相关关系（n=48，P＜0．001），而与近地面气压和CO2浓度呈负相关关系。
The soil respiration diurnal variation of 6 communities in summer in Baihua mountainous areas in west Beijing was monitored and analyzed with LI-8100 automated soil CO2 flux system. The results showed that diurnal soil respiration rate of different communities displayed a unimodal curve, the peak value appeared in 13：00～16：00 and the minimum value appeared in 03：30～07：30 Contribution rate of the litter respiration to the soil respiration was from 6.62% to 40.83%; The diurnal soil CO2 release in Artemisia lavandulaefoli community was the highest about 254880 μmol/m^2. d, the lowest one Robinia pseudoacacia community about 190944μmol/m^2. d, the diurnal litter CO2 release in Hinus tabulaeformis community was the highest about 91368μmol/m^2. d, the contribution rate reached 40.83%, the lowest one forbs was 13608μmol/m^2. d, the contribution rate was 6.62%. Linear correlation analysis revealed that litter respiration rate and litter thickness, litter stock showed significant positive correlation （n=6, p=0. 05）, but it had no significant correlation with the organic matter of litter; There was a significant correlation between soil respiration rate and environment factors, the soil respiration rate showed significant positive correlation with the soil temperature （n=48,p〉0. 001） , but it showed negative correlation with the atmospheric pressure and CO2 concentration on ground surface.
出处
《中国草地学报》
CSCD
2008年第1期78-86,共9页
Chinese Journal of Grassland
基金
北京市科学技术委员会项目(D0605046040191)
关键词
呼吸速率
凋落物
呼吸贡献率
Respiration rate
Litter
Respiration contribution rate
