氧18示踪法在浮游植物生产力监测中的应用  

Application of^(18)O Tracer Method in Phytoplankton Production Observations

作　　者：曹凌志 高咏卉 Cao Lingzhi;Gao Yonghui(School of Oceanography,Shanghai Jiao Tong University,Shanghai 200030,China)

机构地区：[1]上海交通大学海洋学院,上海200030

出　　处：《中国海洋大学学报（自然科学版）》2023年第12期95-103,共9页Periodical of Ocean University of China

基　　金：国家自然科学基金项目(4160060782)资助。

摘　　要：浮游植物光合和呼吸作用是调节河口碳交换的重要过程。本文在模拟实验基础上,采用重氧水(H 218 O)加富法培养海水,用四极杆质谱精确测定溶氧的变化和重氧(18 O 16 O)的生物富集速率,同步测定总生产力(Gross primary production,GPP)与净群落生产力(Net community production,NCP),估测长江口最大浑浊带、锋面地带和冲淡水延伸区域(舟山海域)的水柱积分GPP和NCP。结果表明,受光限制影响,最大浑浊带水柱积分GPP低(6.11 mmol·m^(-2)·d^(-1)),呼吸作用造成NCP为负值,呈异养状态;锋面水柱积分GPP和NCP分别为164.87和135.91 mmol·m^(-2)·d^(-1),主要由表层水体的硅藻贡献,周转效率高达0.82;舟山海域水柱积分GPP和NCP分别为235.44和180.75 mmol·m^(-2)·d^(-1),主要由0~15 m水体的甲藻贡献,周转效率为0.77。Phytoplankton photosynthesis and respiration are the fundamental process in regulating carbon exchange in estuaries.On the basis of simulation experiments,we enriched seawater with H 218 O for incubations and used quadrupole mass spectrometry to precisely measure variation of dissolved O 2 and biological enrichment of(18 O 16 O),in order to measure gross primary production(GPP)and net community production(NCP)simultaneously,and thus estimate the column integrated GPP and NCP in the turbidity maximum zone,the plume front and the extension area of dilute water(waters of Zhoushan)off the Changjiang estuary.It shows that the maximum turbidity zone is affected by light limitation,with low GPP(6.11 mmol·m^(-2)·d^(-1)),and respiration leads to negative NCP and heterotrophy;The column integrated GPP and NCP in the plume front are 164.87 and 135.91 mmol·m^(-2)·d^(-1),respectively,which are mainly contributed by diatoms in the surface layer.The turnover rate reaches 0.82.The column integrated GPP and NCP in the waters of Zhoushan are 235.44 and 180.75 mmol·m^(-2)·d^(-1),respectively,which are mainly contributed by dinoflagellates in the 0~15 m layer.The turnover rate in the waters of Zhoushan is 0.77.

关 键 词：总生产力 净群落生产力 最大浑浊带 锋面地带 舟山海域 

分 类 号：TH843[机械工程—仪器科学与技术]