At present, field measurement is the main means of acquiring soil temperature data, which is spatially and temporally discontinuous. The prediction model of soil temperature should be built based on continuous measured data. Based on the soil temperature data of different layers (0 cm, 5 cm, 10 cm, 15 cm, and 20 cm) and the air temperature above and below the canopy, the data were measured continuously in a nearly 30-year-old Robinia pseudoacacia plantation in the hilly zone in Jiyuan City of He’nan Province in 2006 and 2007, the relationship between soil temperature and air temperature was analyzed, a mathematical model for predicting soil temperature was developed based on daily air temperature data in 2006, and the predictions were tested based on the data of 2007. The results show that:The variation trends of soil temperature of different layers and air temperature are basically the same; as soil depth increased, the impact of the soil increased, yet the correlation of soil temperature and air temperature decreased. According to the growth status of trees, a year can be divided into four phases of phenology. The correlation of soil temperature and air temperature was significant when the leaf area index was small. Therefore, the structure of forest canopy had obvious impact on the soil temperature. The model based on air temperature can provide a valuable and accurate tool for predicting temperature of shallow soil. However, to accurately predict deep soil temperature, more factors should be taken into account.

在土壤热物理学理论的基础上，利用三针式热脉冲探头，介绍了基于热脉冲技术测定土壤热通量的原理和方法，并进行了试验检验。结果表明：热脉冲法的土壤热通量计算值与土壤热通量板法测定值相符较好，标准偏差为0.674 W·m-2，热脉冲方法可准确应用于土壤热通量的测定。此外，对热通量结果的相位分析表明，10 cm深地温峰值的出现时间比热通量峰值滞后约1 h。与热通量板法相比，热脉冲方法还具有对土壤扰动小、热接触阻力低的优点，具有广泛应用的前景。

[目的] 分离并量化土壤自养呼吸和异养呼吸，探讨各自贡献率及其随季节变化的动态特征。[方法] 采用壕沟法和气体红外分析法，研究黄河小浪底库区山地栓皮栎人工林土壤总呼吸、自养呼吸和异养呼吸速率的季节动态变化、贡献率和环境影响因子。[结果] 表明：栓皮栎人工林总土壤呼吸、自养呼吸和异养呼吸均呈夏季速率高、冬季速率低。栓皮栎土壤总呼吸、自养呼吸及异养呼吸速率与5 cm土壤温度均呈极显著指数相关，温度敏感性系数Q10值大小为自养呼吸（3.40） > 异养呼吸（2.90） > 土壤总呼吸（2.45）；栓皮栎土壤总呼吸、自养呼吸、异养呼吸速率与0~10 cm土壤体积含水量均显著线性相关；土壤总呼吸、自养呼吸速率与0~10 cm土壤电导率显著相关。土壤总呼吸和异养呼吸的温度敏感系数Q10值均在冬季最大，夏秋季最小；而自养呼吸的Q10值则呈相反的变化趋势。栓皮栎人工林自养呼吸和异养呼吸对土壤总呼吸的月贡献率为13.23%~37.33%和62.67%~86.76%，且自养呼吸的贡献率与土壤温度的季节变化规律相似。土壤总呼吸、异养呼吸与自养呼吸的CO2年通量分别为1 616.41、1 199.39、417.02 g·m-2·a-1。[结论] 经过区分与定量化土壤总呼吸及其组分，确定异养呼吸为本研究区栓皮栎人工林土壤总呼吸的主要组分，作用于异养呼吸的生物与非生物因子均能显著影响整个森林生态系统表层CO2总排放通量的大小，进一步为该研究区森林生态系统碳循环与能量流动的进一步量化研究提供参考。