Isotopic Correction Factors for Zooplankton Storage

Tristan Blechinger, Denver Link, Jenna K.R. Nelson, and Grechen J.A. Hansen

Lakes & Sites

Model Output & Results

## refitting model(s) with ML (instead of REML)
## refitting model(s) with ML (instead of REML)
ANOVA Results
npar AIC BIC logLik deviance Chisq Df Pr(>Chisq)
Carbon
1:1 1 95.73418 96.86967 -46.86709 93.73418 NA NA NA
Mixed 4 47.98013 52.52210 -19.99006 39.98013 53.754051 3 0.000000
Nitrogen
1:1 1 44.84955 45.98505 -21.42478 42.84955 NA NA NA
Mixed 4 43.76129 48.30327 -17.88064 35.76129 7.088266 3 0.069137
Fixed Effects for Carbon Model
Estimate Std. Error t-value
Intercept 2.84194 1.87409 1.516
Ethanol 1.15545 0.06437 17.951
Random Effects for Carbon Model
Name Variance Std. Dev
Lake (Intercept) 0.1735 0.4166
Residual NA 0.2762 0.5256

Random Lake Effects

Caterpillar plots showing the 95% confidence intervals for each lake’s random intercept. Overlapping zero indicates no deviation from the fixed effect (ethanol treatment) intercept. Carbon shown top and nitrogen shown bottom.

## $Lake

## $Lake

Acknowledgements & Citations

This project was supported by the University of Minnesota’s Office of Undergraduate Research.

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  3. Feuchtmayr, H. and Grey, J. 2003. Effect of preparation and preservation procedures on carbon and nitrogen stable isotope determinations from zooplankton. Rapid Communications in Mass Spectrometry. 17(23): 2605-2610.
  4. Eloranta, A. 2013. The Variable Position of Arctic Charr (Salvelinus alpinus (L.)) in Subarctic Lake Food Webs. Thesis for PhD. Advisor: Dr. Roger I. Jones & Dr. Kimmo K. Kahilainen