The basal respiration rate at 10°C (R10) and the temperature sensitivity of soil respiration (Q10) are two premier parameters in predicting the instantaneous rate of soil respiration at a given temperature. However, the mechanisms underlying the spatial variations in R10 and Q10 are not quite clear. R10 and Q10 were calculated using an exponential function with measured soil respiration and soil temperature for 11 mixed conifer-broadleaved forest stands and nine broadleaved forest stands at a catchment scale. The mean values of R10 were 1.83 µmol CO2 m−2 s−1 and 2.01 µmol CO2 m−2 s−1, the mean values of Q10 were 3.40 and 3.79, respectively, for mixed and broadleaved forest types. Forest type did not influence the two model parameters, but determinants of R10 and Q10 varied between the two forest types. In mixed forest stands, R10 decreased greatly with the ratio of coniferous to broadleaved tree species; whereas it sharply increased with the soil temperature range and the variations in soil organic carbon (SOC), and soil total nitrogen (TN). Q10 was positively correlated with the spatial variances of herb-layer carbon stock and soil bulk density, and negatively with soil C/N ratio. In broadleaved forest stands, R10 was markedly affected by basal area and the variations in shrub carbon stock and soil phosphorus (P) content; the value of Q10 largely depended on soil pH and the variations of SOC and TN. 51% of variations in both R10 and Q10 can be accounted for jointly by five biophysical variables, of which the variation in soil bulk density played an overwhelming role in determining the amplitude of variations in soil basal respiration rates in temperate forests. Overall, it was concluded that soil respiration of temperate forests was largely dependent on soil physical properties when temperature kept quite low.
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机译：10°C的基础呼吸速率（R10）和土壤呼吸的温度敏感性（Q10）是预测给定温度下土壤呼吸瞬时速率的两个主要参数。但是，R10和Q10中的空间变化所依据的机理尚不清楚。 R10和Q10是使用指数函数计算的，其中有11个针叶阔叶混交林和9个阔叶混交林的集水规模，并测量了土壤呼吸和土壤温度。 R10的平均值为1.83 µmol CO2 m -2 s -1 和2.01 µmol CO2 m -2 s -1 < / sup>，混合和阔叶林类型的Q10平均值分别为3.40和3.79。森林类型不会影响这两个模型参数，但是两种森林类型的决定因素R10和Q10有所不同。在混交林林地，R10随针叶树与阔叶树种的比率而大大降低。随土壤温度范围，土壤有机碳（SOC）和土壤总氮（TN）的变化而急剧增加。 Q10与草本层碳储量和土壤容重的空间变化呈正相关，与土壤碳氮比呈负相关。在阔叶林中，R10受到基础面积，灌木碳储量和土壤磷（P）含量变化的显着影响。 Q10的值很大程度上取决于土壤的pH值以及SOC和TN的变化。 R 10 和Q 10 的51％的变化可以由五个生物物理变量共同解释，其中土壤容重的变化在确定土壤生物量中起了压倒性的作用。温带森林土壤基础呼吸速率变化幅度。总的来说，可以得出结论，温度保持很低时，温带森林的土壤呼吸很大程度上取决于土壤的物理特性。
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