Continuous Monitoring of Plankton Density in Pond Water by Flow-type Plankton Monitor.

To automate plankton examination, we have developed a plankton monitor that uses flow-type video imaging equipment and an image processor. This monitor was operated for 11 successive days (from 25 Aug. to 4 Sept. 1998) and had the following results. (1) Monitor counts agree well with microscopic examination counts of non-centrifuged samples (micro:monitor=1 : 1.4). (2) We also performed multiple regression analysis between the monitor line-particle counts and meteorological data (solar radiation, precipitation, temperature, wind speed). The line-particle counts had a high correlation with the level of solar radiation and precipitation measured two days previously (multiple correlation coefficient: 0.98).