EARLY HEARING DETECTION AND INTERVENTION VIRTUAL CONFERENCE
MARCH 2-5, 2021
(Virtually the same conference, without elevators, airplane tickets, or hotel room keys)
6/05/2017 | 2:45 PM - 3:00 PM | SEASONAL DYNAMICS OF EXTRACELLULAR ENZYME ACTIVITY AND NUTRIENT AVAILABILITY WITHIN AN AGRICULTURALLY INFLUENCED OXBOW LAKE | 306A
SEASONAL DYNAMICS OF EXTRACELLULAR ENZYME ACTIVITY AND NUTRIENT AVAILABILITY WITHIN AN AGRICULTURALLY INFLUENCED OXBOW LAKE
We examined seasonal patterns in water column nutrients, sediments, chlorophyll a (chl. a) and extracellular enzyme activity (EEA) within a remnant oxbow lake to assess relationships between nutrient availability and EEA. Chl. a was limited by total solids (TS) concentrations > 123 mg/L which occurred throughout winter and early spring. Rising chl. a concentrations from May thru September corresponded with sharp declines in dissolved inorganic nitrogen (DIN) in early summer coupled with more gradual declines in dissolved inorganic phosphorus (DIP). Patterns in Beta-N-acetylglucosaminindase (NAG) + l-leucine aminopeptidase (LAP) activity peaked in late august during a period of near maximum chl. a concentrations and consistently low DIN, whereas acid phosphatase (AP) activity peaked in late September when chl. a was still high and DIP reached its annual minimum. Michaelis-Menten dynamics explained the response of algal growth to experimental N and P gradients in bioassays using summer plankton communities. Algal bioassays also confirmed that increasing DIP availability suppressed AP activity whereas increasing NAG + LAP activity appeared to be more related to increasing algal biomass than decreasing DIN.
- C07 Lentic Ecology
- C01 Algae
- C10 Biogeochemistry
Presentation:
This presentation has not yet been uploaded.
Handouts:
Handout is not Available
Transcripts:
CART transcripts are NOT YET available, but will be posted shortly after the conference
Presenters/Authors
Jason M. Taylor
(), USDA, Agricultural Research Service, National Sedimentation Lab, jason.taylor@ars.usda.gov;
ASHA DISCLOSURE:
Financial -
Nonfinancial -