论文部分内容阅读
采用静态封闭箱式技术对长白山阔叶红松林土壤CO2的排放通量进行一年的观测,通过多元回归分析了土壤CO2排放速率与8环境因子间的关系。结果表明:土壤CO2排放通量与土壤5 cm温度和0-20 cm平均土壤含水量(体积比)呈显著正相关。土壤呼吸与温度和含水量分别表现出幂函数和指数关系。土壤温度和含水量显著影响土壤呼吸的变化。当土壤含水量(体积百分比)大于25%时,土壤呼吸Q10值从1.14(含水量<25%)降低到1.09(含水量>25%)。在土壤含水量固定不变时,土壤温度能反映土壤呼吸的86%的变化。当土壤温度固定不变时,土壤含水量能反映土壤呼吸的32%的变化。建立土壤呼吸温度幂函数和含水量指数关系的非线性双因子模型。温度和水分双因子土壤呼吸模型能反映森林土壤呼吸的91%的时空变化。土壤呼吸温度和水分双因子模型估算的年土壤CO2排放通量比土壤呼吸Q10幂函数模型估算值高11%。
A static closed box technique was used to observe the soil CO2 emissions from the broad-leaved Korean pine forest in Changbai Mountain. The relationship between CO2 emission rate and environmental factors was analyzed by multiple regression analysis. The results showed that there was a significant positive correlation between soil CO2 flux and soil 5 cm soil temperature and 0-20 cm average soil water content (volume ratio). Soil respiration and temperature and water content showed power function and exponential relationship, respectively. Soil temperature and water content significantly affect soil respiration. Soil respiration Q10 decreased from 1.14 (water content <25%) to 1.09 (water content> 25%) when soil moisture content (% by volume) was more than 25%. The soil temperature reflects the 86% change of soil respiration when the soil water content is constant. When soil temperature is constant, soil moisture content can reflect the change of 32% of soil respiration. A non-linear two-factor model for establishing the relationship between soil respiration temperature exponential function and water content index was established. The temperature and water two-factor soil respiration model can reflect the temporal and spatial changes of 91% of the soil respiration in forest. The annual soil CO2 emission flux estimated from the two-factor model of soil respiration temperature and moisture is 11% higher than the estimate of the soil respiration Q10 power function model.