Abstract
Our results establish formally that phytoplankton counting error decreases with increasing biomass. When combining the individual density estimates to yield a single figure, error propagation introduces great uncertainty around succession and diversity indices. Furthermore, counting error increases the value of succession indices for communities where all species change at the same rate above the expected value of 0. Consequently, conclusions based on the comparison of succession and diversity indices should only be drawn when the uncertainty derived from counting error is considered. © 1990 Oxford University Press.