Nutrients and Phytoplankton in a Shallow, Hypereutrophic Urban Lake: Prospects for Restoration
AbstractUniversity Lake, a shallow, artificial, urban lake adjacent to the campus of Louisiana State University, has a long history of water quality problems, including algal blooms, fish kills, and high concentrations of fecal indicator bacteria. Periodic dredging of the lake is necessary to prevent its return to swampland. This study was undertaken to elucidate the roles of allochthonous versus autochthonous nutrients as causes of water quality problems in the lake, with the expectation that this information would help identify strategies for lake restoration. Photosynthetic rates and concentrations of inorganic nutrients and phytoplankton pigments were measured over a period of one year. More than 90% of the chlorophyll a (chl a) in the lake was accounted for by Chlorophyceae, Cyanophyceae, and Bacillariophyceae. Concentrations of chl a, which averaged 75 μg L−1, fluctuated weekly during dry weather by as much as a factor of four. Phytoplankton growth rates were about 30% higher 1–2 days after rain events than after periods of dry weather, the implication being that allochthonous nutrient loading has a significant effect on the dynamics of the phytoplankton community in the lake. Therefore, dredging of sediments will likely produce no long-term improvement in water quality. More than 100 storm drains currently discharge into the lake, and diversion of those drains may be the most cost-effective strategy for effecting a long-term improvement in water quality. View Full-Text
Share & Cite This Article
Norris, B.; Laws, E.A. Nutrients and Phytoplankton in a Shallow, Hypereutrophic Urban Lake: Prospects for Restoration. Water 2017, 9, 431.
Norris B, Laws EA. Nutrients and Phytoplankton in a Shallow, Hypereutrophic Urban Lake: Prospects for Restoration. Water. 2017; 9(6):431.Chicago/Turabian Style
Norris, Brianne; Laws, Edward A. 2017. "Nutrients and Phytoplankton in a Shallow, Hypereutrophic Urban Lake: Prospects for Restoration." Water 9, no. 6: 431.
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.