石榴-绿豆间作系统土壤呼吸及其影响因子研究

土壤呼吸是陆地生态系统碳循环的重要环节，在维持全球碳平衡中发挥着重要作用。于2010年6—10月，在黄河小浪底森林生态系统研究站，利用Li-8100红外动态土壤呼吸自动观测系统、温湿度自动观测系统测定了石榴-绿豆间作系统（间作系统）和绿豆单作系统（单作系统）土壤呼吸速率(soil respiration rate, SRR)及土壤温度和湿度。结果表明:1) 间作系统和单作系统的SRR日波动在晴天-多云呈单峰变化趋势，在阴天日波动变化幅度较小。间作系统的SRR高于单作系统。整个观测时期内间作系统和单作系统的平均SRR分别为2.996 μmol ·m^-2· s^-1和2.378 μmol·m^-2·s^-1。2) 间作系统和单作系统SRR与15 cm处土壤温度存在显著的指数相关关系，在该深处的Q₁₀值分别为2.462和1.793 3) 间作系统和单作系统与20 cm处的土壤体积含水量与SRR的相关关系均不明显。

Soil Respiration of Punica granatum -Phaseolus radiatus Intercropping System in Hilly Area of Northern China

Soil respiration has been shown to be a major contributor to the carbon budget and plays an important role in the global carbon cycle. In this study, soil respiration under the Punica granatum-Phaseolus radiatus intercropping system (IS) and P. radiatus monoculture system (MS) were measured by Li-8100 in Xiaolangdi Forest Ecosystem Research Station of the Yellow River during the growing season from June to September 2010. The relationship between the soil respiration and environment factors were studied. The results showed that SRR in sunny-cloudy days showed a significant diurnal variation in two systems. The SRR showed a single peak curve in both systems, and the fluctuations at the cloudy days changed little. The changes of the SRR on sunny-cloudy days were consistent with the variation of soil temperature, and the SRR of the IS was higher than that in MS. During the study period, the average SRR was 2.996 μmol m^-2·s^-1 and 2.378 μmol m^-2·s^-1 for IS and MS, respectively. The temperature sensitivity of soil respiration (Q₁₀) for the IS and MS were 2.462 and 1.793, respectively. No significant relationship was observed between soil respiration and soil water content in two systems.