An investigation of Douglas Lake periphyton productivity in relation to chlorophyll a and biovolume estimations.

Abstract

Periphyton communities at three depths in Douglas Lake were examined to give baseline information of productivity and algal biovolume. The data can be used as a comparison in the future to examine the effect of disturbances (i.e., global warming or zebra mussels) on the phytoplankton community. Two sampling dates were used to collect cores from 2 m, 4 m and 6 m depths. The cores were then sub-sampled to obtain both chlorophyll a and biovolume estimations. Statistical analysis included mean, standard error of the mean, and a 1-way ANOVA with a Tukey test. We found no significance with depth for chlorphyll a or phaeophytin. At depths of 2 m and 6 m there is a significant difference between green, blue-green, and diatom biovolumes, however, there is no difference in biovolumes within greens, blue-greens, or diatoms in relation to depth. There is no difference of biovolumes between the major groups at a depth of 4 m.