西安南郊不同人工植被下土壤CO_2浓度研究

Soil CO_2 Concentration under Different Artificial Vegetations in South Suburb of Xi'an

利用红外CO2监测仪对西安南郊不同植被、不同深度条件下的土壤CO2浓度进行了多次昼夜观测。观测结果表明:从早8:00到次日早8:00,土壤CO2浓度具有从低到高再到低的昼夜变化规律,这种变化特点与昼夜温度变化基本一致,但两者在时间上并不完全同步;土壤CO2浓度从总体来看是白天和夜间很接近;松树林下的土壤CO2浓度大于草地土壤CO2浓度,草地土壤CO2浓度大于竹林下的土壤CO2浓度。

We have measured the diurnal changes of soil CO2 concentration under different vegetation covers by using of the infrared monitoring instrument in the south suburb of Xi＇an. Analyzing result showed that the soil CO2 concentration had a changing law of ＂low to high and then to low＂ from the morning to the next morning, which was basically accordant to the change of temperature, but the change of the former was later than that of the latter. The soil CO2 concentration was greater in daytime than in nighttime. Temperature was the main factor of determining the change law of the soil CO2 concentration. The soil CO2 concentration under the study vegetation covers was： in pine tree〉in grassland〉in bamboo shrub.