【摘要】 研究了夏季东海海水中和大气中一氧化碳(CO)的浓度分布、海-气通量和表层海水中CO的微生物消耗。夏季东海大气中CO的体积分数范围为63×10-9~120×10-9,平均值为87×10-9(SD=18×10-9,n=37),呈现出近岸高,远海低和北高南低的特点。夏季东海表层海水中CO的浓度范围为0.24~5.51nmol/L,平均值为1.48nmol/L(SD=1.46,n=37),CO的浓度受太阳辐射影响明显;CO在垂直分布上表现出浓度随深度增加迅速减小的特征,浓度最大值出现在表层。调查期间表层海水中CO相比大气处于过饱和状态,过饱和系数变化范围为3.65~113.55,平均值为23.63(SD=24.56,n=37),这表明调查海域是大气中CO的源。CO的海-气通量变化范围为0.25~78.50μmol/(m2·d),平均值为9.97μmol/(m2·d)(SD=14.92,n=37)。在CO的微生物消耗培养实验中,CO的浓度随时间增长呈指数降低,消耗过程表现出一级反应的特点,速率常数KCO范围为0.043~0.32/h,平均值为0.18/h(SD=0.088,n=9),KCO与盐度之间存在负相关关系。更多还原

【Abstract】 Carbon monoxide(CO)concentration distribution,sea-to-air flux and microbial consumption rate constants,along with atmospheric CO mixing ratios,were measured in the East China Sea in summer.Atmospheric CO mixing ratios varied from 63×10-9 to 120×10-9,with an average of 87×10-9(SD=18×10-9,n=37).Overall, the concentrations of atmospheric CO displayed a decreasing trend from the coastal stations to the offshore stations and a decreasing trend from the northern stations to the southern stations.The surface water CO concentrations in the investigated area ranged from 0.24to 5.51nmol/L,with an average of 1.48nmol/L(SD=1.46,n=37).The surface water CO concentrations were affected significantly by sunlight.Vertical profiles showed that CO concentrations declined with depth rapidly,with the maximum values appearing in the surface water.The surface CO concentrations were oversaturated and the saturation factors ranged from 3.65to 113.55,with an average of 23.63(SD=24.56,n=37).The East China Sea was a net source of atmospheric CO.The sea-to-air fluxes of CO in the East China Sea ranged from 0.25to 78.50μmol/(m2·d),with an average of 9.97μmol/(m2·d)(SD=14.92, n=37).In the incubation experiments,CO concentrations decreased exponentially with incubation time and the processes conformed to the first order reaction characteristics.The microbial CO consumption rate constants in the surface water(KCO)ranged from 0.043to 0.32h-1,with an average of 0.18h-1(SD=0.088,n=9).A negative correlation between KCOand salinity was observed in the present study.更多还原