Enumeration of natural<i>Microcystis</i>populations

Abstract

Three methods for estimating the cell concentrations of natural, colonial Microcystis populations are described, and the results are compared statistically. Ultrasonic disruption of colonies is most conveniently applied to dense populations and gives results comparable with those obtained by alkaline hydrolysis. Excessive exposure to ultrasonic waves may destroy cells. A regression relating cell concentration to mean colony volume can, subject to conditions described, give crude estimates of Microcystis at low population densities or in mixed populations.