Use of phosphorus to reduce blooms of the benthic diatom Didymosphenia geminata in an oligotrophic stream
Blooms of the benthic alga, Didymosphenia geminata [Lyngbye (Schmidt)], were first documented in Rapid Creek, South Dakota, in 2002 and have since been associated with changes to aquatic resources. Low concentration of P has been associated with D. geminata stalk development (i.e., blooms), so we considered elevating P as a possible method to reduce D. geminata blooms. We conducted 2 whole-stream P-enrichment experiments in Rapid Creek during 2007 and 2008. Enrichment with a slow-release fertilizer (Osmocote®: 14-14-14) in 2007 significantly reduced D. geminata blooms (indexed by D. geminata biomass) compared to upstream control sites. The reduction in biomass was less pronounced as distance from the enrichment source increased, a result indicating that P augmentation effectively decreased D. geminata biomass. In 2008, we implemented a before-after–control-impact (BACI) study to assess effects of a quick-release fertilizer (MAP: 11-52-0) on D. geminata biomass. The addition of 6 μg/L P to Rapid Creek resulted in a significant decrease in D. geminata biomass within 0.6 km downstream of the nutrient-addition point. Effects on D. geminata biomass were not evident further downstream. This study provides evidence to support the hypothesis that low P concentration regulates D. geminata blooms.
Citation Information
Publication Year | 2015 |
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Title | Use of phosphorus to reduce blooms of the benthic diatom Didymosphenia geminata in an oligotrophic stream |
DOI | 10.1086/683038 |
Authors | Daniel A. James, Max L. Bothwell, Steven R. Chipps, John Carreiro |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Freshwater Science |
Index ID | 70187286 |
Record Source | USGS Publications Warehouse |
USGS Organization | Coop Res Unit Leetown |