土壤CO_2浓度的动态观测、模拟和应用

Dynamic observation,simulation and application of soil CO_2 concentration:A review

土壤CO2浓度不仅是地上、地下生物活动的反映,其变化对未来大气CO2浓度和气候变化也有重要影响.本文综述了国内外土壤CO2浓度的原位测定方法及其优缺点,分析了不同时(昼夜、几天、季节、年际)空(剖面、立地、景观)尺度上土壤CO2浓度的变化规律和影响因素,概括了现有土壤CO2浓度的模拟模型和发展态势,并总结了土壤CO2浓度梯度法在土壤呼吸研究中的应用和限制因素.最后展望了未来有待研究的4个领域:1)研发适于恶劣土壤环境(如淹水、石质土)的土壤CO2气体采集、测定技术;2)探讨土壤CO2浓度对天气变化的响应及其调控机理;3)加强土壤CO2浓度空间异质性的研究;4)扩大通量梯度法在热带、亚热带土壤呼吸测定中的应用.

Soil CO2 concentration is the consequences of biological activities in above-and belowground,and its fluctuation may significantly affect the future atmospheric CO2 concentration and the projected climate change.This paper reviewed the methodologies for measuring the soil CO2 concentration in situ as well as their advantages and disadvantages,analyzed the variation patterns and controlling factors of soil CO2 concentration across the temporal （diurnal,several days,seasonal and inter-annual） and spatial （soil profile,site and landscape） scales,introduced the primary empirical and mechanical models for estimating and predicting soil CO2 concentration,and summarized the applications and constraints of soil CO2 concentration gradient in determining soil respiration.Four research priorities were proposed,i.e.,to develop new techniques for collecting and determining the soil CO2 in severe soil conditions （e.g.,flooding,lithoso and others）,to approach the responses of soil CO2 concentration to weather change and related regulation mechanisms,to strengthen the researches on the spatial heterogeneity of soil CO2 concentration,and to expand the applications of soil CO2 concentration gradient in the measurement of tropical-subtropical soil respiration.