Algal Community Composition and Water Quality in an Urban Tidal Tributary
Description/Abstract/Artist Statement
Knitting Mill Creek is an urban sub-tributary of the Lafayette River in Norfolk, VA prone to algal blooms and water quality impairments. Bloom initiation and phytoplankton succession were assessed by collecting water samples 2-3 times per week from May through August, 2015. Physical and chemical parameters (water, temperature, salinity, 10 pH, dissolved oxygen, Secchi depth, chlorophyll fluorescence, total nitrogen, and total phosphorus) were measured along with analyses of algal species composition. Significant heterogeneity in vertical structure was detected, with subsurface Chla 2-3x surface concentrations in some cases, indicating limitations of traditional surface monitoring. A total of 48 phytoplankton species were identified in Knitting Mill Creek during the study, dinoflagellates were the dominant group present, and among the dinoflagellates observed was the harmful algal bloom (HAB) forming species, Cochlodinium polykrikoides. Cochlodinium is responsible for extensive blooms throughout the lower Chesapeake Bay region when water conditions are favorable. Cochlodinium was present in Knitting Mill Creek for 10 weeks with peak blooms occurring mid-June, mid-July, and early August followed by a decrease in biomass. Further applications of this study could be used to monitor other urban tributaries to assess water quality based on algal species composition dominated by species that cause harmful algal blooms.
Presentation Type
Event
Disciplines
Biology | Hydrology | Marine Biology
Location
Learning Commons @ Perry Library, Conference Room 1310
Start Date
2-13-2016 9:00 AM
End Date
2-13-2016 10:00 AM
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Algal Community Composition and Water Quality in an Urban Tidal Tributary
Learning Commons @ Perry Library, Conference Room 1310
Knitting Mill Creek is an urban sub-tributary of the Lafayette River in Norfolk, VA prone to algal blooms and water quality impairments. Bloom initiation and phytoplankton succession were assessed by collecting water samples 2-3 times per week from May through August, 2015. Physical and chemical parameters (water, temperature, salinity, 10 pH, dissolved oxygen, Secchi depth, chlorophyll fluorescence, total nitrogen, and total phosphorus) were measured along with analyses of algal species composition. Significant heterogeneity in vertical structure was detected, with subsurface Chla 2-3x surface concentrations in some cases, indicating limitations of traditional surface monitoring. A total of 48 phytoplankton species were identified in Knitting Mill Creek during the study, dinoflagellates were the dominant group present, and among the dinoflagellates observed was the harmful algal bloom (HAB) forming species, Cochlodinium polykrikoides. Cochlodinium is responsible for extensive blooms throughout the lower Chesapeake Bay region when water conditions are favorable. Cochlodinium was present in Knitting Mill Creek for 10 weeks with peak blooms occurring mid-June, mid-July, and early August followed by a decrease in biomass. Further applications of this study could be used to monitor other urban tributaries to assess water quality based on algal species composition dominated by species that cause harmful algal blooms.
Comments
Faculty Mentor: Dr. T. A. Egerton