primary production in the delta: nutrient considerations to...
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Primary Production in the Delta: Nutrient Considerations to Guide Conservation
Alexander E. Parker, PhD California Maritime Academy
Many contributors to data collection and interpretation:
Dugdale / Wilkerson Lab Sacramento River Study
Richard Dugdale Chris Foe
Frances Wilkerson Nutrient Ratios Project
Sarah Blaser Patricia Glibert
Victoria Hogue Jeff Alexander
Al Marchi Microcystis Project
Adam Pimenta Hans Paerl
Erica Kress Tim Otten
Jamie Lee IRWM / Suisun Marsh Studies
Allison Johnson Risa Cohen
Suisun Bay/ SWAMP
Karen Taberski
Primary Production in the Delta: Nutrient Considerations to Guide Conservation
The Delta is a mosaic of nutrient environments.
Experiments suggests that nutrient form, ratio and concentrations can alter algal community composition, nutrient and C uptake, and microbial function.
The relative importance of nutrient versus other drivers of patterns in primary production is likely site-specific. Modification of the Delta should consider potential nutrient-driven outcomes.
Thinking About Nutrients: The Ocean Perspective
-
The availability of nitrogen limits primary production in the ocean.
From: Sigman and Hain 2012
Thinking About Nutrients: The Ocean Perspective
-
The availability of nitrogen limits primary production in the ocean.
From: Sigman and Hain 2012
The availability of nitrogen limits primary production.
The distinction between “New” (i.e. nitrate-based) and “Regenerated” (ammonium-based) production is important in the supply and fate of primary production.
Thinking About Nutrients: The Ocean Perspective
-
The availability of nitrogen limits primary production in the ocean.
From: Sigman and Hain 2012
Diatom-based food web based on “NEW” production.
Microbial loop favored through “REGENERATED” Production.
How do phytoplankton respond when nutrients are no longer limiting?
Phytoplankton Response to Anthropogenic Nutrients
200-L mesocosms amended with either NH4 or NO3 (50uM) and incubated for 72 hours.
Parker, 2004
>2-fold increase in chlorophyll-a, increase in DOC and bacterial activity
Phytoplankton Response to Anthropogenic Nutrients
200-L mesocosms amended with either NH4 or NO3 (50uM) and incubated for 72 hours.
Parker, 2004
>2-fold increase in chlorophyll-a, increase in DOC and bacterial activity
-
Increasing N:P
Glibert, 2010
Increasing contribution by NH4
Phytoplankton Response to Anthropogenic Nutrients
Increasing N : P
Phytoplankton in northern SFE
Modified from
J. Thompson
Ephemeral spring and more persistent fall phytoplankton blooms in recent years.
Phytoplankton in northern SFE
Modified from
J. Thompson
2000 bloom associated with an improved light field, low ammonium concentrations and rapid nitrate uptake.,
Wilkerson et al 2006
Phytoplankton in northern SFE
Modified from
J. Thompson
2010 diatom (Entomoneis, Cyclotella, Melosira) blooms lasted several weeks,
Dugdale et al 2012
Phytoplankton
increase 10-fold
over 2009.
Zooplankton
increase 9-fold
over 2009
Delta smelt (70%) and
longfin smelt (194%)
increased (FMWT survey)
Phytoplankton in northern SFE
Dugdale et al 2012
What Do We Know About Nutrients in the SFE?
Long history of measurements for the San Francisco Estuary (e.g. USGS).
Main stem of Sacramento and San Joaquin Rivers.
Paradigm is that nutrients are replete / not limiting.
Primary Production in the Delta: Nutrient Considerations to Guide Conservation
The Delta is a mosaic of nutrient environments.
Experiments suggests that nutrient form, ratio and concentrations can alter algal community composition, nutrient and C uptake, and microbial function.
The relative importance of nutrient versus other drivers of patterns in primary production is likely site-specific. Modification of the Delta should consider potential nutrient-driven outcomes.
Nutrient Distribution Are Highly Variable in Space and Time in the Delta
Western and Eastern Suisun Marsh
Large (4-fold) spatial and temporal variation in nutrients in Suisun Marsh.
From Parker & Cohen 2010
Nutrient Distribution Are Highly Variable in Space and Time in the Delta
Western and Eastern Suisun Marsh
Large (4-fold) spatial and temporal variation in nutrients in Suisun Marsh.
From Parker & Cohen 2010
Nutrient Distribution Are Highly Variable in Space and Time in the Delta
Western and Eastern Suisun Marsh
Large (4-fold) spatial and temporal variation in nutrients in Suisun Marsh.
From Parker & Cohen 2010
Nutrient Distribution Are Highly Variable in Space and Time in the Delta
Western and Eastern Suisun Marsh
Large (4-fold) spatial and temporal variation in nutrients in Suisun Marsh.
From Parker & Cohen 2010
Nutrient Distribution Are Highly Variable in Space and Time in the Delta
Tidal wetlands in the confluence
Large (>10-fold) variation over relatively small spatial scales.
From Parker & Cohen 2010
Station map and river regions Upper River
-30 to -9.1 km
WWTP 0 - 20 km
Central River 21-43km
Lower River 51 -65km Suisun Bay 75 – 97 km
San Pablo Bay
122km
Nutrient Distribution Are Highly Variable in Space and Time in the Delta
From Parker et al. 2012
> 3-fold N and P increase at a single point source
Sacramento River
Nutrient Distribution Are Highly Variable in Space and Time in the Delta
From Parker et al. 2010
Summer N-limited in upper river and >4 fold variation in NH4 seasonally.
Sacramento River
Nutrient Distribution Are Highly Variable in Space and Time in the Delta
From SRWWTP, in Parker et al. 2010
>4 fold variation in NH4 seasonally.
Sacramento River
Nutrients and Primary Production in the Delta
The Delta is a mosaic of nutrient environments.
Experiments suggests that nutrient form, ratio and concentrations can alter algal community composition, nutrient and C uptake, and microbial function.
The relative importance of nutrient versus other drivers of patterns in primary production is likely site-specific. Modification of the Delta should consider potential nutrient-driven outcomes.
Elevated chlorophyll-a associated with NO3 uptake
From Dugdale et al. 2007
Nutrients and Primary Production in the Delta
Ammonium (NH4) inhibits phytoplankton access to nitrate (NO3)
From Dugdale et al. 2007
NH4 ≈ 1 μM (0.014 mg /L) inhibits NO3 uptake by 60%
Nutrients and Primary Production in the Delta
NH4 ≈ 4 μM (0.056 mg /L) inhibits NO3 uptake.
From Dugdale et al. 2007
Nutrients and Primary Production in the Delta
NH4 inhibition of NO3 uptake is not universal (nor are threshold NH4 concentrations) across phytoplankton taxa (Dortch 1990). NH4 inhibits transport of NO3 into the cell. NH4 inhibits nitrate reductase (a necessary step in NO3 assimilation into protein) activity and specificity.
Nutrients and Primary Production in the Delta
From Parker et al. 2012 ECSS
Chlorophyll-a is dominated by diatoms
Nutrients and Primary Production in the Delta – Microcystis
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0 10 20 30 40 50 60
V, h
-1
Nitrogen concentration, µM
NH4
Urea
NO3
Glut. acid
J. Lee, in prep.
CONT +NH4 +NO3 +UREA +PO4
+NH4/
PO4
+NO3/
PO4
+UREA/
PO4
X or
50%
PAR
10%
PAR
N, μM 5 30 30 30 4 30 30 30
P, μM 2 2 2 2 5 8 8 8
N:P 2.5:1 15:1 15:1 15:1 0.8:1 4.4:1 3.8:1 3.8:1
Photo: Paerl
Nutrients and Primary Production in the Delta – Microcystis
Parker et al. in prep
0
10
20
30
40
50
60
Control +NH4 +NO3 +Urea +PO4 +NH4/PO4 +NO3/PO4 +Urea/PO4
d
b
a
c c
d
c c
~250% control
~150% control
~200% control ~150%
control
Ch
loro
ph
yll-
a, µ
g L-1
Nutrients and Primary Production in the Delta – Microcystis
Nutrients and Primary Production in the Delta
From Pulse of the Estuary 2012; Based on Kress 2012
From Pulse of the Estuary 2012; Based on
Kress 2012
The Delta is a mosaic of nutrient environments.
Experiments suggests that nutrient form, ratio and concentrations can alter algal community composition, nutrient and C uptake, and microbial function.
The Challenge: Placing Experimental Results in an Ecological Framework
The relative importance of nutrient versus other drivers of patterns in primary production is likely site-specific. Modification of the Delta should consider potential nutrient-driven outcomes.
Jeff Alexander
Acknowledgements Primary Production in the Delta: Nutrient Considerations to Guide Conservation
Funding from: The Delta Science Program Water Quality Control Boards (R2, R5) The State and Federal Contractors Water
Agency CA Dept. Fish and Wildlife Thanks to: Sacramento Regional County Sanitation
District R/V Questuary