A Lagrangian model for phototaxis-induced thin layer formation

摘要: Abstract We have developed a Lagrangian model to investigate potential mechanism based on phototaxis behavior of phytoplankton cells for the formation thin layers. assume that all follow time-regulated diurnal vertical migration during which they experience photo-acclimation Denman and Marra (1986) model. When cell experiences stress due strong light exceeds threshold level, swims downward, away from light. applied one dimensional second order turbulence closure generates realistic surface mixing condition given set physical parameters, such as wind optical water type. For chosen swimming velocities prescribed behavior, we found that, in coastal type Jerlov III type, layer takes place up 5 m s −1 winds, while 10 m s winds cause sufficiently prevent layer. also investigated effects changing irradiance onset photoinhibition, initial density profile random walk swimming. In conclusion, photoinhibition may be possible low value occur either upwelling or exposure.