Overview of the phytoplankton and water quality of Lake Maumelle for 2009

Since 1989 the United States Geological Survey (USGS) and Central Arkansas Water (CAW) have collected water quality and phytoplankton samples from Lake Maumelle in Central Arkansas. These samples were collected from three locations within the reservoir. Phytoplankton samples for 2009 were identified to genus and counted. The phytoplankton did not follow a typical succession pattern for north temperate lakes. Starting in late winter, Chlorophyta tended to be the dominant division followed by Cyanophyta in the fall. Diversity was relatively high at all sampling locations and no differences among sites were detected. Total phosphorus appeared to be the limiting nutrient. Based on total phosphorus and chlorophyll a, Lake Maumelle ranges between oligotrophic and mesotrophic. Total nitrogen indicted the Lake was oligotrophic. Secchi disc indicated eutrophic conditions. Secchi disc may not be appropriate for estimating lake trophic status in reservoirs in a more southern part of the temperate zone.