Send to

Choose Destination
See comment in PubMed Commons below
Environ Eng Sci. 2013 Apr;30(4):179-186.

Model Simulation of Diurnal Vertical Migration Patterns of Different-Sized Colonies of Microcystis Employing a Particle Trajectory Approach.

Author information

Graduate Institute of Environmental Engineering, National Taiwan University , Taipei, Taiwan, Republic of China .


Microcystis, a genus of potentially harmful cyanobacteria, is known to proliferate in stratified freshwaters due to its capability to change cell density and regulate buoyancy. In this study, a trajectory model was developed to simulate the cell density change and spatial distribution of Microcystis cells with nonuniform colony sizes. Simulations showed that larger colonies migrate to the near-surface water layer during the night to effectively capture irradiation and become heavy enough to sink during daytime. Smaller-sized colonies instead took a longer time to get to the surface. Simulation of the diurnally varying Microcystis population profile matched the observed pattern in the field when the radii of the multisized colonies were in a beta distribution. This modeling approach is able to take into account the history of cells by keeping track of their positions and properties, such as cell density and the sizes of colonies. It also serves as the basis for further developmental modeling of phytoplanktons that are forming colonies and changing buoyancy.


Microcystis; buoyancy regulation; stratification; trajectory model; vertical migration

PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for PubMed Central
    Loading ...
    Support Center