Impact of tidally induced residual circulations on chemical oxygen demand (COD) distribution in Laizhou Bay, China

Wanqing Chi; Xiaodong Zhang; Wenming Zhang; Xianwen Bao; Yanling Liu; Congbo Xiong; Jianqiang Liu; Yongqiang Zhang

doi:10.1016/j.marpolbul.2019.110811

Impact of tidally induced residual circulations on chemical oxygen demand (COD) distribution in Laizhou Bay, China

Mar Pollut Bull. 2020 Feb:151:110811. doi: 10.1016/j.marpolbul.2019.110811. Epub 2020 Jan 29.

Authors

Wanqing Chi¹, Xiaodong Zhang², Wenming Zhang³, Xianwen Bao⁴, Yanling Liu⁵, Congbo Xiong⁶, Jianqiang Liu⁶, Yongqiang Zhang⁶

Affiliations

¹ Key Lab of Submarine Geosciences and Prospecting Techniques, MOE and College of Marine Geosciences, Ocean University of China, Qingdao 266100, China; The First Institute of Oceanography, Ministry of Natural Resources, China, Qingdao 266061, China.
² Key Lab of Submarine Geosciences and Prospecting Techniques, MOE and College of Marine Geosciences, Ocean University of China, Qingdao 266100, China.
³ Department of Civil and Environmental Engineering, University of Alberta, Edmonton T6G 1H9, AB, Canada. Electronic address: wenming@ualberta.ca.
⁴ College of Oceanic and Atmospheric Sciences, Ocean University of China, Qingdao 266100, China.
⁵ College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China.
⁶ The First Institute of Oceanography, Ministry of Natural Resources, China, Qingdao 266061, China.

PMID: 32056605
DOI: 10.1016/j.marpolbul.2019.110811

Abstract

To understand the impact of hydrodynamics on pollutant transport in Laizhou Bay, China, we conducted numerical simulations using Mike 21. The model was calibrated with good agreements to field monitoring data at various monitoring stations. The simulation results show a clockwise and an anti-clockwise tidally-induced residual circulation in the western and eastern bay, respectively. Historical COD monitoring data also indicate two rings of high COD concentration in the same regions of the bay. This suggests that the hydrodynamics of tidal and residual currents is the main cause of the ring-shaped high COD concentration field in the bay. Pollutant inputs from inland rivers are also important for the COD distribution, making the near-shore side of the COD ring higher than the offshore side. Regions with higher retention time in the bay are usually associated with higher COD concentrations. This study is useful in understanding the mechanism of pollutant spatial distribution and subsequent pollution control in a sea bay.

Keywords: COD; Eulerian field; Lagrangian particle tracking; Laizhou Bay; Mike 21; Tidally induced residual current.

MeSH terms

Bays*
Biological Oxygen Demand Analysis
China
Environmental Monitoring*
Water Pollutants, Chemical*

Substances

Water Pollutants, Chemical