Light is a major resource for phytoplankton and has a
complex pattern of spatial and temporal variability
(Litchman, 2000). Suspended matter in lake water
increases in autumn and spring, resulting in minimum
transparency. During the summer the transparency was
at its maximum level. There was also a significant
correlation between the growth of phytoplankton and
transparency in Orduzu Dam Lake since the largest
populations of all algae occurred during the summer
whilst indiviual numbers were low in winter.
No relation was observed between diatom growth and
pH level since high and low individual numbers were
observed at similar pH levels.