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应用静态箱／气象色谱法对南亚热带3种森林土壤地表CO2排放通量的季节动态及其对环境变化的响应规律进行了2年的连续观测,结果表明:季风常绿阔叶林、针阔叶混交林和马尾松针叶林(S+L)CO2年排放总量分别为3942．2,3422．36和2163．02 gCO2．m-2·a-1,并且3种林分具有相同的季节性变化特征,排放高峰均出现在6～8月,这期间的土壤CO2排放量占全年排放总量的35．9％,38．1％和40．2％:不同森林土壤CO2排放过程对环境变化的响应有明显差异,具体体现在针叶林(PF)对温度变化的响应较阔叶林(BF)和混交林(MF)敏感,Q10值较大,而且CO2排放通量的季节变化幅度较大,表明结构单一的森林生态系统抗干扰能力较差;3种森林土壤CO2排放通量与土壤温度(Ts)、土壤含水量(Ms)和空气压力(Pa)均呈显著相关;但多元回归分析表明,空气压力对森林土壤CO2排放通量的影响并不显著;基于经验模型,以土壤5 cm处温度和土壤含水量两个指标可以分别说明阔叶林、混交林和针叶林土壤CO2排放通量变异的75．7％,77．8％和86．5％,该模型可以较好地描述受水分胁迫的土壤或干旱或半干旱土壤CO2的排放过程．
The seasonal dynamics of surface CO2 fluxes and their responses to environmental changes in three types of forest soils in southern subtropics were observed using static box / GC-2 for 2 years. The results showed that the monsoon evergreen broad-leaved forest, The annual discharge of CO2 in mixed forest and masson pine coniferous forest (S + L) is 3942.2, 3422.36 and 2163.02 gCO2, respectively. m-2 · a-1, and the three types of forests had the same seasonal variation with the peak of emission occurring from June to August. During this period, the soil CO2 emission accounted for 35.9% of the total annual discharge, 38.1% and 40.2% respectively. The response of different forest soil CO2 emissions to environmental changes is obviously different, which is reflected in the response of the coniferous forest (PF) to temperature changes as compared with that of the broadleaved forest (BF) and the mixed forest MF), the Q10 value is larger, and the seasonal variation of CO2 emission flux is larger, indicating that the anti-interference ability of forest ecosystem with single structure is poorer. The fluxes of CO2 emissions and soil temperature (Ts), soil (Ms) and air pressure (Pa). However, multivariate regression analysis showed that the effect of air pressure on the CO2 flux of forest soils was insignificant. Based on the empirical model, the soil temperature The two indices of water quantity can explain 75.7%, 77.8% and 86.5% of the variations of soil CO2 flux in broad-leaved forest, mixed forest and coniferous forest, respectively. Soil or CO2 emissions from arid or semi-arid soils.