南极普里兹湾及其邻近海域悬浮颗粒有机物的碳同位素组成及其影响因素  

Stable carbon isotopic composition of suspended particulate organic matter in the Prydz Bay and its adjacent areas

作　　者：任春燕[1] 陈敏[1,2] 高众勇[3] 郭劳动[1,4] 贾仁明 刘萧[1] 邱雨生[1] 郑敏芳[1] 

机构地区：[1]厦门大学海洋与地球学院,福建厦门361102 [2]厦门大学近海海洋环境科学国家重点实验室,福建厦门361102 [3]国家海洋局第三海洋研究所大气与全球变化重点实验室,福建厦门361005 [4]美国威斯康星大学水科学学院,密尔沃基wi53204

出　　处：《海洋学报》2015年第12期74-84,共11页

基　　金：南北极环境综合考察与评估专项(CHINARE01-04-03;04-01-06;04-04;04-03-05);国家自然科学基金杰出青年基金项目(41125020)

摘　　要：依托中国第29次南极科学考察航次开展了南大洋普里兹湾及其邻近海域悬浮颗粒有机物碳同位素组成(δ13CPOC)的研究,结合温度、盐度、营养盐和溶解CO_2的数据,揭示了影响研究海域颗粒有机物碳同位素组成的主控因素,计算出混合层中浮游植物吸收无机碳过程的碳同位素分馏因子。结果表明,普里兹湾及其邻近海域的δ13CPOC介于-28.5‰^-21.1‰,平均值为-24.6‰,表现出湾内大于湾外的特征。浮游植物同化吸收CO_2过程的碳同位素分馏是影响研究海域混合层δ13 CPOC的主要因素,根据δ13CPOC和1/[CO_2(aq)]的线性拟合关系,计算出浮游植物同化吸收CO2过程的碳同位素分馏因子εp为23.4‰。δ13CPOC的垂直分布随深度增加而增大,反映出颗粒有机物垂向输送过程中颗粒有机物再矿化过程同位素分馏作用的影响。To better understand carbon and particle dynamics in the Prydz Bay and its adjacent areas,stable carbon isotopic composition in suspended particulate organic matter（POM）along with aqueous CO2,nutrients and hydrographic data were measured to examine the spatial and vertical distributions ofδ13CPOCand their controlling factors during the 29 th Chinese Antarctic Research Expedition.Furthermore,carbon isotope fractionation factor during the assimilation of dissolved inorganic carbon（DIC）by phytoplankton in the mixed layer was estimated.Our results showed thatδ13CPOCranged from-28.5‰to-21.1‰ with an average of-24.6‰,showing an increase trend from the inner bay to open waters outside the Bay.Carbon isotope fractionation factor during phytoplankton DIC assimilation in the mixed layer was estimated to be 23.4‰ based on the relationship betweenδ13CPOC and1/[CO2（aq）],and was the major controlling factor forδ13CPOCvalues in the mixed layer in the Prydz Bay and its adjacent areas.Values ofδ13CPOCincreased in general with increasing depth in the study areas,ascribing to the isotope fractionation during POM remineralization.

关 键 词：悬浮颗粒有机物 δ13CPOC 碳同位素分馏因子 南极普里兹湾 

分 类 号：X145[环境科学与工程—环境科学]