Seasonal evolution and controlling factors of bottom oxygen depletion in the Bohai Sea
Seasonal evolution and controlling factors of bottom oxygen depletion in the Bohai Sea
复制标题
渤海海底缺氧季节演变及控制因素
DOI：
10.1016/j.marpolbul.2021.113199
复制
发表时间：
2021
影响因子：
5.8
通讯作者：
Nan Zheng
中科院分区：
文献类型：
--
作者：
Haiyan Zhang;Hao Wei;Liang Zhao;Huade Zhao;Shian Guo;Nan Zheng
利用物理-生态地球化学耦合模式研究了渤海耗氧的季节演变及其控制因素。比较表明，该模式再现观测到的重要的物理和地球化学变量的时空变化。底质氧的年周期表现为夏季明显下降，秋季补充增强。秦皇岛和黄河口海域分别发育有两个缺氧区，缺氧速率较高，缺氧持续时间较长。氧耗的演变主要受分层和生物耗氧的控制，但也受到横向运输的调节。强烈的分层早于氧耗尽建立并维持其发展。生物耗氧量决定了分层条件下的两个缺氧区。受反气旋环流影响的横向输运有利于QHD外氧耗的扩大，但会使YRE外氧耗减少。
A coupled physical-biogeochemical model is used to investigate the seasonal evolution and controlling factors of oxygen depletion in the Bohai Sea (BS). Comparisons show that the model reproduces observed spatiotemporal variations of important physical and biogeochemical variables well. Bottom oxygen in the BS shows an annual cycle with significant drawdown in summer and enhanced replenishment in fall. Two oxygen-depleted regions off Qinhuangdao (QHD) and the Yellow River estuary (YRE) develop separately and experience higher oxygen depletion rates and longer durations of low-oxygen conditions. The evolution of oxygen depletion is primarily controlled by stratification and biological oxygen consumption but is also modulated by lateral transport. Strong stratification is established earlier than oxygen depletion and maintains its development. The biological oxygen consumption determines the two oxygen-depleted regions under stratified conditions. Lateral transport influenced by anticyclonic circulations favors an expansion of oxygen depletion off QHD but alleviates oxygen depletion off the YRE.