The effect of herbicides on phytoplankton in Wazimenya Bay. L. Victoria

During the in-lake herbicide trials in Wazimenya Bay, Cyanobacteria dominated the phytoplankton, constituting more than 85%. The green algae and diatoms were always rare. There was a low species diversity. Algal cell counts were generally lower below the Hyacinth mat (5m inside) than at the edge (Om). There was no significant difference in the cell counts from the Rodeo and Weedar-64 sprayed stations nor between those from the Weedar-64 and control stations. However, there was a significant difference in the counts between Rodeo and control stations. But, the control counts were almost always lower than the Rodeo counts, an observation which could not easily be explaine