Nineteen reservoirs in Guangdong province were sampled in June and December in 2000, roughly corresponding to the flood and dry seasons. A total of 142 species of phytoplankton belonging to 89 genera in 7 phyla were observed.They were as follows: 84 chlorophyta, 25 Bacillariophyta, 19 Cyanophyta, 9 Euglenophyta, 2 Pyrrophyta and Chrysophyta and only 1 Cryptophyta was found. The dominant species in the reservoirs were either Cyanophyta or Bacillariophyta. The cell density and chlorophyll concentration i...