南海碳源汇的区域与季节变化特征及控制因素研究进展  

Advances in Seasonal Variations and Controls of the Air-sea CO Flux in the South China Sea

作　　者：张晓辉[1] 彭亚兰 黄根华[1] Zhang Xiaohui;Peng Yalan;Huang Genhua(Marine Environmental Monitoring Central Station of the State Oceanic Administration,Zhuhai Guangdong 519015,China)

机构地区：[1]国家海洋局珠海海洋环境监测中心站,广东珠海519015

出　　处：《地球科学进展》2020年第6期581-593,共13页Advances in Earth Science

基　　金：自然资源部南海局海洋科学技术局长基金项目“珠江口邻近海域海—气界面碳通量的季节变化及控制因素”(编号:1729)资助。

摘　　要：南海碳循环是全球碳循环的重要组成部分。厘清南海CO2通量问题,对阐明全球碳循环过程,完善全球碳循环数据库具有重要意义。对南海4个典型特征区域(北部陆架、北部陆坡及海盆、吕宋海峡西侧海域和中南部海盆)的海表CO2分压、CO2通量和控制因素的研究进展进行了归纳总结。结果显示,南海北部陆架海表CO2分压区域差异显著,珠江冲淡水上游低盐区为强碳源,海表CO2分压常年处于超饱和状态,最高值达405.3~810.6 Pa,下游离岸开阔海域(盐度大于33.7)冬季海表CO2分压低至35.2~37.0 Pa,为弱的碳汇。南海北部陆坡、海盆受温度调控,暖季是碳源,冷季是碳汇,夏季海表CO2分压最高达45.0 Pa,冬季海表CO2分压最低为34.7 Pa。吕宋海峡西侧海域碳源/汇受温度、季风和水团等因素影响较大,春季海表CO2分压与大气CO2分压接近于平衡状态,冬季升高至38.4~47.5 Pa,高于大气CO2分压。中南部海盆表现为大气CO2弱或中等强度的源,海表CO2分压年均值为41.0 Pa。总体上,南海大部分海域在全年尺度上表现为弱的碳源,每年向大气释放(18±10)Tg C的CO2。虽然南海碳循环研究已取得了一定进展,但仍缺少长期的现场观测与数据积累。今后应进一步加强海—气CO2分压时间序列研究和海—气CO2交换通量的遥感研究。Marine carbon cycle of the South China Sea is an important part of global carbon cycle.Researches on the air-sea CO2 flux in the South China Sea will help us understand the global carbon cycle and improve the global carbon system parameter database.This paper concisely summarized the changes of partial pressure of CO2(p CO2),air-sea CO2 fluxes(FCO2),and related environmental factors in four regions in domains in the South China Sea.The low-salinity area of the upper reaches of the Pearl River estuary in the northern of South China Sea shelf area acted as a strong source of atmospheric CO2,with high p CO2(405.3~810.6 Pa)all year round.The lower area of the Pearl River estuary(salinity>33.7)acted as a weak sink of CO2 in winter,with relatively low p CO2(35.2~37.0 Pa).The northern slope/basin in the South China Sea acted as a source of CO2 in warm seasons with a relatively high p CO2(45.0 Pa),and acted as a sink of CO2 in cold seasons with a relatively low p CO2(34.7 Pa).The west of the Luzon Strait acted as a sink of CO2 in spring,while it acted as a source of CO2 in other seasons,with relative high p CO2(38.4~47.5 Pa)in winter.The central/southern basin in the South China Sea acted as sources of CO2,with relative high p CO2(41.0 Pa)all the year.Generally,the estimation of annual sea-air CO2 fluxes showed that most domains in the South China Sea served as weak sources of atmospheric CO2.In the future,more researches should be focused on the time-series of sea surface p CO2 and the remote sensing of the sea-air CO2 fluxes.

关 键 词：CO2分压 海—气界面CO2通量 南海 边缘海 控制因素 珠江冲淡水 

分 类 号：P736.4[天文地球—海洋地质]