盐生荒漠净生态系统碳交换的涡度相关法和箱式法对比  

Net ecosystem carbon exchange in saline desert: A comparison of eddy covariance method and chamber-based method

作　　者：马杰[1,2,3] 吴玉[1,2,3] 郑新军[1,2] 唐立松[1,2] 王玉刚[1,2] 

机构地区：[1]中国科学院新疆生态与地理研究所荒漠与绿洲国家重点实验室,乌鲁木齐830011 [2]中国科学院阜康荒漠生态系统国家站,新疆阜康831505 [3]中国科学院大学,北京100049

出　　处：《生态学杂志》2013年第10期2627-2634,共8页Chinese Journal of Ecology

基　　金：国家重点基础研究发展计划项目(2009CB825102);国家国际科技合作计划项目(2010DFA92720-05)资助

摘　　要：将叶面积指数的季节动态,与箱式法同步观测得到的同化枝净光合(呼吸)速率和土壤呼吸速率相结合,对群落碳交换进行估算,并以此验证盐生荒漠涡度相关数据的可靠性。结果表明:盐生荒漠生态系统年叶片生物量为51.30±5.56 g·m^(-2),其中90.45%以上来源于多枝柽柳的贡献;而整个生长季,群落叶面积指数(LAI)呈单峰形式变化,从5月30日—9月30日,LAI介于0.18~0.30,并在第197天达到最大值。涡度相关法和箱式法对群落碳交换的测定结果表明,群落碳交换存在显著的季节变化,并于7月中旬达到碳同化峰值,与LAI有显著的相关性(P<0.001)。对比发现,两种测量方法对群落碳交换日过程的测定结果有很好的一致性,但对夜间生态系统呼吸的测定,涡度相关法较箱式法存在略微的低估,引起这种低估的原因可能是夜间湍流较弱。By coupling the seasonal variation of leaf area index （LAI） with the synchronous chamber-based measurement of leaf net photosynthesis （respiration） rate and soil CO2 flux, the ecosystem carbon exchange in a saline desert was estimated, and the results were used to verify the reliability of eddy covariance data. The annual total leaf biomass of the saline desert ecosystem was 51.30±5.56 g·m-2, of which, more than 90.45% were contributed by Tamarix ramosissima. In the whole growth season, the LAI varied in single peak pattern, being 0.18-0.30 from the 30th of May to the 30th of September and peaked at the 197th day. The measurement of the carbon flux by eddy covariance method and chamber-based method showed that the net ecosystem carbon exchange had an obvious seasonal variation, which peaked in mid-July and had significant correlation with LAI （P〈0.001）. Through comparison, the daytime ecosystem carbon exchange from eddy covariance measurement was agreed well with that from chamberbased measurement, but the nighttime ecosystem carbon exchange from eddy covariance measurement was slightly underestimated, probably due to the weak turbulence during the night.

关 键 词：盐生荒漠 净生态系统碳交换 涡度相关法 箱式法 

分 类 号：X171[环境科学与工程—环境科学]