INFLUENCE OF STRATIFICATION AND INTERNAL WAVES ON DISTRIBUTION OF ENVIRONMENTAL FACTORS OF SEAWATER ON THE EAST CHINA SEA INNER CONTINENTAL SHELF IN SPRING

Based on the measurements of the velocity and the environmental factors of seawater at the P2 anchor station on the East China Sea inner continental shelf in spring,it was found that strong stratification(with a value of buoyancy frequency of 1×10?3 s?2) is caused by the interface between coastal water and shelf mixing water.The variations of temperature and salinity in the water column are related to the flow field.Under the influence of stratification,distribution of environmental factors presents a two-layered structure,above and below the pycnocline.Internal waves consisted of semidiurnal internal tides and near inertial waves are simultaneously generated by the stratification.The time when stratification layer jumps up and Ri?1 4 exists in the pycnocline corresponds to that when cross-stratification of chlorophyll and dissolved oxygen takes place.This indicates internal waves provide environmental factors that energize the cross-stratification mixing.Stratification and internal waves work together toward vertical mixing of environmental factors;the former inhibits,and the latter enhances mixing.