摘要
利用涡动相关技术对黄土高原半干旱区SACOL站2007-2012年连续6 a的CO2通量进行观测,并结合气象观测数据,分析兰州大学半干旱气候与环境观测站(SACOL站)净生态系统碳交换量(NEE)的变化特征以及环境影响因子。结果表明:(1)黄土高原半干旱区SACOL站NEE年累积平均值为-214.50±43 gC/m^2,其中生长季节累积平均值为-171.58±41 gC/m^2,非生长季节累积平均值为-42.92±5 gC/m^2;(2)SACOL站NEE的日变化呈"U"型,净辐射是影响NEE日变化的主要因子。NEE日平均值为-1.15 gC/m^2,表现为明显的CO2吸收,即黄土高原半干旱区是重要的碳汇区;(3)NEE值有明显的年际差异和季节变化特征,生长季节比非生长季节变化幅度大;NEE在生长季节主要受到土壤湿度的影响,而土壤温度会影响非生长季节NEE的变化。
Based on the continuous observation data of carbon dioxide flux using eddy covariance technique( ECT) at the Semi- Arid Climate and Environment Observatory of Lanzhou University( SACOL) during 2007- 2012,and combined meteorological observations,the variation characteristics of net ecosystem carbon exchange( NEE) and environment factors influencing NEE there were analyzed.Results are as follows:( 1) The annual cumulative average NEE value at SACOL was- 214. 50 ± 43 gC/m^2,thereinto,- 171. 58 ± 41 gC/m^2 during growing season,and- 42. 92 ± 5 gC/m^2 during non- growing season.( 2) The diurnal variation curve of NEE at SACOL presented an asymmetrical U shape,and net radiation was the main influencing factor. The SACOL was an obvious sink of carbon with daily average NEE value of- 1. 15 gC/m^2.( 3) The variation of carbon dioxide flux showed significant seasonal and interannual differences. The amplitude of variation was bigger in growing season,which was affected by soil conditions.
出处
《干旱气象》
2016年第1期88-95,共8页
Journal of Arid Meteorology
基金
国家重大科学研究计划项目(2012CB955302)
国家自然科学基金项目(4140050023)
兰州大学中央高校基本科研业务费专项资金(lzujbky-2014-102)共同资助