南海东北部及吕宋海峡邻近海域海水和大气中挥发性卤代烃的浓度分布与海-气通量  

Distributions and Sea-to-Air Fluxes of Volatile Halocarbons in the Northeastern South China Sea and the Luzon Strait’s Adjacent Marine Area

作　　者：刘志雯 何真 邹亚文 杨桂朋[1,2] Liu Zhiwen;He Zhen;Zou Yawen;Yang Guipeng(The Key Laboratory of Marine Chemistry Theory and Technology,Ministry of Education,College of Chemistry and Chemical Engineering,Ocean University of China,Qingdao 266100,China;Laboratory for Marine Ecology and Environmental Science,Pilot National Laboratory for Marine Science and Technology(Qingdao),Qingdao 266237,China)

机构地区：[1]中国海洋大学化学化工学院,海洋化学理论与工程技术教育部重点实验室,山东青岛266100 [2]青岛海洋科学与技术试点国家实验室海洋生态与环境科学功能实验室,山东青岛266237

出　　处：《中国海洋大学学报（自然科学版）》2023年第1期85-94,共10页Periodical of Ocean University of China

基　　金：国家自然科学基金项目(41830534)资助。

摘　　要：挥发性卤代烃(VHCs)是大气中一类重要的挥发性有机污染物。本文于2020年9月对南海东北部及吕宋海峡邻近海域海水及大气中的二氯二氟甲烷(CFC-12)、三氯氟甲烷(CFC-11)、溴甲烷(CH_(3)Br)和碘甲烷(CH_(3)I)的浓度进行了同步测量,探讨了4种VHCs浓度的水平分布及其影响因素,并估算了CH_(3)Br和CH_(3)I的海-气通量。结果表明,调查海域海水中CFC-12、CFC-11、CH_(3)Br和CH_(3)I的浓度平均值分别为(1.96±0.84)、(5.35±4.86)、(1.26±0.57)和(2.58±0.88)pmol·L^(-1)。海水中CH_(3)Br和CH_(3)I的分布是生物生产释放、陆源输入和光化学等多种因素共同作用的结果。大气中CFC-12、CFC-11、CH_(3)Br和CH_(3)I的浓度平均值分别为(480.65±68.55)、(184.07±31.22)、(9.21±4.35)和(1.13±0.65)pptv。结合气象参数和后向轨迹分析发现海洋洁净气团扩散、陆源污染气团的输送和海-气交换作用会共同影响大气中VHCs的分布。CH_(3)Br和CH_(3)I的海-气通量分别为(1.59±3.22)和(9.51±4.57) nmol·m^(-2)·d^(-1),表明调查期间南海东北部及吕宋海峡邻近海域是CH_(3)Br和CH_(3)I的源。Volatile halocarbons(VHCs) are an important class of volatile organic pollutants in the atmosphere. Concentrations of dichlorodifluoromethane(CFC-12), trichlorofluoromethane(CFC-11), methyl bromide(CH_(3)Br) and methyl iodide(CH_(3)I) were measured in the surface water and atmosphere of the northeastern South China Sea and the Luzon Strait’s adjacent marine area in September 2020. The distributions of the four VHCs and their influencing factors were discussed, and the sea-to-air fluxes of CH_(3)Br and CH_(3)I were calculated. The mean concentrations of CFC-12, CFC-11, CH_(3)Br and CH_(3)I in the surface seawater were(1.96±0.84),(5.35±4.86),(1.26±0.57) and(2.58±0.88) pmol·L^(-1), respectively. Complicated factors including biological production, terrestrial inputs and photochemistry controlled the distribution of CH_(3)Br and CH_(3)I. The mean atmospheric concentrations of CFC-12, CFC-11, CH_(3)Br and CH_(3)I were(480.65±68.55),(184.07±31.22),(9.21±4.35) and(1.13±0.65) pptv, respectively. The results of meteorological parameters and backward trajectory revealed that the diffusion of clean oceanic air masses, transposition of polluting air masses from terrestrial sources and sea-to-air exchange influenced the distribution of VHCs in the atmosphere. The sea-to-air fluxes of CH_(3)Br and CH_(3)I were(1.59±3.22) and(9.51±4.57) nmol·m^(-2)·d^(-1), respectively, indicating that the northeastern South China Sea and the Luzon Strait’s adjacent marine area were sources of CH_(3)Br and CH_(3)I during the survey period.

关 键 词：挥发性卤代烃 分布 海-气通量 南海 

分 类 号：P734.4[天文地球—海洋化学]