淮北平原农林复合生态系统非生长季CO2通量变化特征

CO_2 Flux of an Agroforestry Ecosystem in Non-growing Seasons in Huaibei Plain

采用开路式涡度相关系统对淮北平原农林复合生态系统非生长季的CO2通量特征进行连续监测,并基于晴好天气10Hz高频数据直接计算而来的经过简单修正的通量数据来探讨河南省西平县杨树人工林非生长季节CO2涡度通量的变化特征。结果表明:(1)生态系统CO2通量具有明显的日变化和季节变化,在日尺度上整个生长季白天表现为碳吸收,在月尺度上秋末和初春表现为明显的碳汇功能;(2)通过对比生态系统CO2通量和土壤呼吸速率,发现土壤呼吸速率对生态系统碳通量的贡献小于植物对它的贡献;(3)5cm土壤呼吸与土壤温度的日内和日际相关关系显著,但生态系统CO2通量与其相关关系不够显著;(4)5cm土壤呼吸的日内变化与土壤含水量相关关系显著,而土壤呼吸日际以及生态系统CO2通量与其相关关系不显著;(5)降雨和复杂的降水过程(如雨夹雪等)过后,生态系统的碳吸收有增加的趋势;而降雪和雾天后生态系统的碳释放有增强的趋势。

The research of the vorticity flux variation of the polar plantation in the non-growing season in Xiping,He＇nan Province was carried out.The research method was to use the OPEC to monitor the CO2 flux of the agroforestry ecosystem in non-growing season in Huaibei Plain,and calculate out the flux data by using the high frequency data in 10 Hz.The results showed that：（1） the ecosystem CO2 flux changed obviously at the scale of day and reason,which daytime displays on the entire growth season was the carbon absorption in the date criterion,however,carbon sequestration was performed obviously in fall end and early spring at the reason scale;（2）by comparing the ecosystem CO2 flux and soil respiration rate,respiration rate found in the soil ecosystem carbon flux is less important than its contribution to plant;（3）the correlation between the soil temperature in the 5 cm soil layer and soil respiration of days and daily interpersonal relationship was significant,though it is not very remarkable with the ecosystem CO2 flux correlational dependence;（4）the correlation between the soil water content in the 5 cm soil and the soil respiration rate was significantly in one day,and it was not significant at the daily scale,and the correlation between the soil water content in the 5 cm soil and the ecosystem CO2 flux was not significant either;（5）the ecosystem carbon sequestration showed an increasing trend after the rainfall and the complex precipitation process,just like sleet;but the carbon emission had the enhancement tendency after the snow and foggy.