lake washington and the synergy between long-term monitoring and experimental research
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Lake Washington and the synergy between long-term monitoring and experimental research. Stephanie E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007. Can we characterize food web interactions based on monitoring data? History of L. Washington Experimental work - PowerPoint PPT PresentationTRANSCRIPT
Lake Washington and the synergy between long-term monitoring and experimental research
Stephanie E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
Can we characterize food web interactions based on monitoring data?
• History of L. Washington
• Experimental work
• Compare expt’l results to structure of long-term data
•Multivariate Autoregressive models (MARs)
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
Photo: John J. Gilbert
Lake Washington
Seattle
Lake Washington
• Clearcut watershed 1800’s• 1.4 million in watershed• Fisheries & tributary manipulations• Municipal sewage until 1968
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
86420
Secc
hi (
m)
Water clarity
Sewage diversion“Recovered”
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
0
2
4
6
Dap
hnia
L-1
86420
Secc
hi (
m)
“Recovered”Daphnia establishment
Water clarity
Sewage diversion
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
0
2
4
6
Dap
hnia
L-1
Daphnia
• Influential grazer
• Predators’ favorite
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
Why the sudden Daphnia appearance?
0
2
4
6
Dap
hnia
L-1
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
Why the sudden Daphnia appearance?
Neomysis
0
2
4
6
Dap
hnia
L-1
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
Why the sudden Daphnia appearance?
Longfin smeltNeomysis
0
2
4
6
Dap
hnia
L-1
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
Why the sudden Daphnia appearance?
Oscillatoria
Longfin smeltNeomysis
0
2
4
6
Dap
hnia
L-1
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
Infante & Abella1985
Experimental evidence for Oscillatoria negative effects
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
Experimental evidence for Oscillatoria negative effects
Infante & Abella1985
010002000300040005000
0 100 200 300 400Oscillatoria/ml
Cryp
tom
onas
/ml
Infante & Litt1985
Experimental evidence for Oscillatoria negative effects and Cryptomonas importance
0
400
800
1200
Asteri
onella
Fragila
ria
Melosira
Steph
anod
iscus
Tabella
ria
Chlorel
la
Cryptom
onas
Dap
hnia
pul
icar
ia b
iom
ass
(ug)
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
Evidence for these relationships in natural data?
0
5
10
15
0 5 10 15
0
1
2
3
4
0 5 10 15ln Oscillatoria biovolume
ln C
rypt
omon
ad b
vln
Dap
hnia
ind
L-1
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
Lake Washington food web
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
Multispecies Autoregressive Models (MARs)
Log abundance of species i tomorrow
Log abundance of species i today
Species-specific constant
xi(t+1) = xi(t) + ai + [bi,j xj(t)] + [ci,k uk(t)]
Ives, Dennis, Cottingham, & Carpenter. 2003. Ecol. Monogr. 73(2)
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
Multispecies Autoregressive Models (MARs)
Log abundance of species i tomorrow
Log abundance of species i today
Species-specific constant Log abundance
of species j today
Effect of species j on species i
xi(t+1) = xi(t) + ai + [bi,j xj(t)] + [ci,k uk(t)]
Ives, Dennis, Cottingham, & Carpenter. 2003. Ecol. Monogr. 73(2)
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
Multispecies Autoregressive Models (MARs)
Log abundance of species i tomorrow
Log abundance of species i today
Species-specific constant Log abundance
of species j today
Effect of species j on species i
Effect of environmental variable k on species i
Level of environmental variable k today
xi(t+1) = xi(t) + ai + [bi,j xj(t)] + [ci,k uk(t)]
Ives, Dennis, Cottingham, & Carpenter. 2003. Ecol. Monogr. 73(2)
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
Multispecies Autoregressive Models (MARs)
•Monthly data from 1962 to 1994
• Fit equations simultaneously for each of 13 phyto- and zooplankton groups
• Coefficients represent interaction strength
xi(t+1) = xi(t) + ai + [bi,j xj(t)] + [ci,k uk(t)]
Ives, Dennis, Cottingham, & Carpenter. 2003. Ecol. Monogr. 73(2)
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
Multispecies Autoregressive Models (MARs)
•Monthly data from 1962 to 1994
• Fit equations simultaneously for each of 13 phyto- and zooplankton groups
• Coefficients represent interaction strength
• Build10,000 random models – select best fit (AIC)
•Bootstrapping for confidence intervals
xi(t+1) = xi(t) + ai + [bi,j xj(t)] + [ci,k uk(t)]
Ives, Dennis, Cottingham, & Carpenter. 2003. Ecol. Monogr. 73(2)
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
MAR food web construction for Lake Washington
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
MAR food web construction for Lake Washington
Hampton, Scheuerell & Schindler 2006S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
MAR food web construction for Lake Washington
Hampton, Scheuerell & Schindler 2006S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
MAR food web construction for Lake Washington
Hampton, Scheuerell & Schindler 2006S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
0204060
1962 1964 1967 1970 1973 1976 1979 1982 1985 1988 1991 1994
0
500000
1000000
1962 1964 1967 1970 1973 1976 1979 1982 1985 1988 1991 1994
Bio
volu
me
# L-1
Daphnia
Cryptomonads
MAR food web construction for Lake Washington
Hampton, Scheuerell & Schindler 2006S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
MAR food web construction for Lake Washington
Hampton, Scheuerell & Schindler 2006S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
• Aspects of historical conceptual model supported
• Inhibitory role of Oscillatoria• Intense competitive effects of Daphnia
• “New” relationships• Cryptomonad importance• Role for picoplankton
MAR food web construction for Lake Washington
Hampton, Scheuerell & Schindler 2006S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
Explore the scale of effects!
Hampton & Schindler 2006
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
Explore the scale of effects!
S. E. Hampton, NCEAS, UCSB, [email protected], 7 July 2007
Weekly
Biweekly
Monthly
Hampton & Schindler 2006