Phytoplankton
-
Upload
isaiah-myers -
Category
Documents
-
view
26 -
download
0
description
Transcript of Phytoplankton
PhytoplanktonMichael L. Parsons
Coastal Watershed InstituteFlorida Gulf Coast University
Phytoplankton (microalgae)
Cyanobacteria (Microcystis)Diatom (Pseudo-nitzschia) Diatom (Actinoptychus)
Dinoflagellate (Karenia brevis)
Dinoflagellate (Gambierdiscus)
Chlorophyte
Silicoflagellate
Haptophyte
Diatom (Chaetoceros)
OverviewThe Good: phytoplankton are the base of the
foodwebThe Bad: too much can have negative impactsThe Ugly: some phytoplankton can produce
toxins that can kill animals and make people sick
Food Web
Phytoplankton Growth RequirementsLightNutrients (nitrogen, phosphorus, carbon,
other compounds)Can serve as indicators of nutrient loading
and light availability
The Good
nutrients plankton
phyto
pla
nkt
on
fish
The Bad
The Ugly
Phytoplankton and the CaloosahatcheeMany factors that affect the growth of
phytoplankton in the Caloosahatchee are controlled/influenced by the flow of the river.
As flow increases:nutrients phytoplanktonresidence time phytoplanktonsalinity assemblage shift
flow nutrients phytoplankton
Doering et al. 2006
flow residence time phytoplankton
Wan et al. 2013
Doering et al. 2006
flow residence time phytoplankton
Wan et al. 2013
flow salinity assemblage shift
Andresen 2011
Andresen 2011
Brand, unpub.
Red Tides and Caloosahatchee Discharges
Brown et al. 2006
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 100000
7
14
21
28
35Red tide frequency versus S79 N loading
mg N/cf/s
% o
f sam
ples
>10
0,00
Kar
enia
bre
vis
per l
iter
“The combined flux of N and P from TB, CH, and the Caloosahatchee River could theoretically supply 11–50% of the N and 11–57% of the P required to support growth of the measured population abundance for each of the three blooms”
Workshop QuestionsWhat driver is the indicator sensitive to?
Nutrients, salinity, light
What constitutes a healthy population of the indicator? Low/moderate cell concentrations; more diatoms and less
cyanobacteria and flagellates
Is the indicator a valued component of the Caloosahatchee system? Should be!
What metrics are appropriate for assessing this indicator? Chlorophyll concentrations; species identifications
Workshop QuestionsWhat are the strengths and limitations of this indicator?
Chlorophyll is an easy (and strong) response variable to measure Cofounding factors (salinity and nutrients; flow and residence time)
What are the relevant gaps and uncertainties in our understanding of the relationship between drivers/stressor and indicator response? Teasing out nutrient loading versus residence time Role of Caloosahatchee in red tides
Could our use of this indicator be improved to address additional drivers/stressors? Yes – can help to optimize flow regimes in different conditions
Next steps? River and red tides Assemblage shifts versus flow