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随着大气CO2浓度的升高,主要由其引起的温室效应与对生物新陈代谢的影响变得越来越显著。森林生态系统在全球碳循环中扮演着重要的角色。为了评估和理解森林土壤CO2通量及其随空气和土壤温度的季节和昼夜变化规律,我们在长白山北坡典型阔叶红松林内利用静态箱技术进行了原位观测。实验在整个生长季(6月初至9月末)昼夜进行,利用气相色谱进行气体分析。结果表明: 长白山阔叶红松林土壤是大气二氧化碳源,其CO2通量具有明显的季节和昼夜变化规律。通量的变化范围是(0.30-2.42)μmol穖-2穝-1,平均值为0.98μmol穖-2穝-1。土壤CO2排放的季节规律表明,土壤CO2通量的变化与气温和土壤温度的变化有关。CO2平均通量的最大值出现在7月((1.27±23%)μmol穖-2穝-1),最小值出现在9月((0.5±28%)μmol穖-2穝-1)。土壤CO2的昼夜波动与土壤温度变化有关,而在时间上滞后于温度的变化。森林下垫面土壤CO2通量与土壤温度显著相关,与6cm深度土层温度相关系数最大。基于气温和土壤温度计算的Q10值范围为2.09-3.40。图2表3参37。
With the increase of atmospheric CO2 concentration, the greenhouse effect mainly caused by it and the impact on the biological metabolism become more and more obvious. Forest ecosystems play an important role in the global carbon cycle. In order to assess and understand the seasonal and diurnal variation of forest soil CO2 fluxes with air and soil temperature, we conducted in-situ observations using the static tank technique in a typical broad-leaved Korean pine forest on the northern slope of Changbai Mountain. Experiments were conducted throughout the growing season (early June to late September) day and night using gas chromatography for gas analysis. The results showed that the soil of Changbai Mountain was the atmospheric carbon dioxide source, and its CO2 flux had obvious seasonal and diurnal variation. The flux varied from (0.30-2.42) μmol 穖 -2 穝 -1 with an average of 0.98 μmol 穖 -2 穝 -1. The seasonal pattern of soil CO2 emission shows that the change of soil CO2 flux is related to the change of temperature and soil temperature. The maximum CO2 flux appeared in July (1.27 ± 23%) μmol 穖 -2 穝 -1) and the minimum appeared in September (0.5 ± 28%) μmol 穖 -2 穝 -1). The diurnal variation of soil CO2 is related to the change of soil temperature, but lags behind the change of temperature in time. The soil CO2 flux was significantly correlated with soil temperature in the underlying forest, and the correlation coefficient was the highest with 6cm soil depth. Q10 values calculated from air temperature and soil temperature ranged from 2.09 to 3.40. Figure 2 Table 3 Reference 37.