长江口邻近海域溶解氧的时空分布及影响因素研究  

Spatial-temporal distribution and dynamics of dissolved oxygen in an adjacent area of the Changjiang estuary

作　　者：孙毅 吕方辉[1,2] 陈钊 刁新源 姜金光[1,2] 魏传杰 潘俊 SUN Yi;Lü Fang-hui;CHEN Zhao;DIAO Xin-yuan;JIANG Jin-guang;WEI Chuan-jie;PAN Jun(Institute of Oceanology Chinese Academy of Sciences,Qingdao 266071,China;Center for Ocean Mega-Science,Chinese Academy of Science,Qingdao 266071,China)

机构地区：[1]中国科学院海洋研究所,山东青岛266071 [2]中国科学院海洋大科学研究中心,山东青岛266071

出　　处：《海洋科学》2021年第12期86-96,共11页Marine Sciences

基　　金：国家自然科学基金项目(41806164)。

摘　　要：基于2018年早春和夏季长江口邻近海域的调查数据,分析溶解氧(DO)的时空分布,并讨论其影响因素。结果表明,夏季DO浓度变化范围为1.58~9.37 mg/L,浮游生物光合作用产生的DO是夏季表层水体过饱和的主要因素;夏季调查海域受台湾暖流北上引起海水层化加强,同时水体富营养化导致表层生物大量繁殖所引起有机碎屑的沉降和耗氧分解作用是底层低氧区存在的主要因素。夏季在台湾暖流影响下底层水体表观耗氧量(AOU)与营养盐成正相关关系,底层有机物耗氧降解过程与营养盐的再生密切相关。早春DO浓度变化范围为7.90~10.1 mg/L,长江口外北部海域和浙江近岸海域海水混合均匀,DO浓度主要受温度控制,而台湾暖流影响区海水出现层化现象,其低DO含量也为低氧区的形成奠定了基础。Using the direct survey data from early spring and summer in 2018,the spatial–temporal distribution and dynamics of dissolved oxygen(DO)in the Changjiang estuary were studied.In summer,the concentration of DO varied from 1.58 to 9.37 mg/L,and the DO produced by plankton photosynthesis played a dominant role in the su-persaturation of the surface seawater.The low oxygen zone in the bottom layer was mainly attributed to the strati-fication generated by the northward movement of the Taiwan Warm Current(TWC),deposition of organic debris,and oxygen consumption caused by the mass proliferation of sea surface organisms due to eutrophication.There were positive correlations between apparent oxygen consumptions in the bottom seawater and nutrients under the influence of TWC.The degradation process of oxygen of bottom organic matter was closely related to nutrient re-generation.In early spring,DO was limited from 7.90 to 10.1 mg/L,and it was mainly controlled by temperature due to the vertical mixing of seawater in the northern area outside the Changjiang Estuary and the coastal area near Zhejiang province.However,stratification occurred in the area affected by TWC,and its low DO laid a foundation for the formation of a hypoxic zone.

关 键 词：溶解氧 长江口 表观耗氧量 低氧区 

分 类 号：X55[环境科学与工程—环境工程]