Appendix A. A trend comparison of stratification onset in Lake Washington using different thresholds of the Schmidt's stability index.

A trend comparison of stratification onset in Lake Washington using different thresholds of the Schmidt's stability index

Appendix B. Figures showing the relation between the timing of different Schmidt stability thresholds and the timing of diatom peaks.

Figures showing the relation between the timing of different Schmidt stability thresholds and the timing of diatom peaks

Stacked barplots of observed average monthly phytoplankton biomass (a, b) and calculated LCEFA concentrations (c, d) in Lake Washington.

<p>Panels (a) and (c) show the group composition during the eutrophic years (1961–1969), and panels (b) and (d) summarize the oligotrophic years (1975–2001) for biomass and LCEFA, respectively. Group specific LCEFA are calculated following <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0130053#pone.0130053.e002" target="_blank">Eq 2</a>. The mean calculated annual LCEFA value across years within each time period is superimposed as a line on panels c and d. Abbreviations follow <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0130053#pone.0130053.g001" target="_blank">Fig 1</a>.</p

Summary of % LCEFA, % ɷ-3, and % ɷ-6 by phytoplankton group and dataset.

<p>Phytoplantkon group mean and standard deviation (sd) for each fatty acid category (% LCEFA, % ɷ-3, and % ɷ-6) and a relative food quality index (FQI) based on total LCEFA content, calculated across unique species (e.g., species N, not all raw fatty acid profiles) in each dataset.</p><p>Summary of % LCEFA, % ɷ-3, and % ɷ-6 by phytoplankton group and dataset.</p

Boxplots of species averages of Σ long-chain essential fatty acids (LCEFA) in six major phytoplankton groups.

<p>(a) Shows the % FA dataset, consisting of 208 averages from 666 raw profiles. (b) Shows the FA % DW dataset, consisting of 55 averages from 105 raw profiles. Group name abbreviations follow <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0130053#pone.0130053.g001" target="_blank">Fig 1</a>. The heavy line is the median, box boundaries are the 25^th and 75^th percentiles, and whiskers extend to the most extreme value within 1.5*IQR (interquartile range). The y-axis is set to show the extent of whiskers, thus some extreme outliers are not plotted (outliers were included in calculation of average group LCEFA).</p

Results of the DISTLM sequential step-wise tests.

<p>Results of distance-based linear model (DISTLM) sequential step-wise tests using adjusted <i>R</i>^<i>2</i> selection criterion for both fatty acid datasets (% FA and FA % DW). This test reports the proportion of the variation explained (prop. var) and the cumulative variation (cum. var) explained by the model at each step. Variable abbreviations: nutrient status [Nutrient (replete or limited)]; light intensity (Light); hours of light (Hrs. Light); temperature (Temp).</p><p>Results of the DISTLM sequential step-wise tests.</p

Distance-based redundancy analysis (dbRDA) ordination of the full multivariate ISTLM.

<p>The DISTLM partitioned the variance in phytoplankton fatty acids explained by the predictor variables for all 621 phytoplankton % FA profiles for which all culture conditions were available [follows <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0130053#pone.0130053.t001" target="_blank">Table 1</a> variable descriptions except salinity here is coded as freshwater (FW) or saline water (SW) for visualization)]. The group abbreviations are: Chl (Chlorophyta); Cry (Cryptophyta); Cya (Cyanobacteria); Dia [diatoms (Bacillariophyceae, Coscinodiscophyceae, Fragilariophyceae)]; Din (Dinophyta); and Hap (Haptophyta). The first two axes explained 75% of the variability in the fitted model. The top two ranked variables in the model for this dataset, group and salinity, are identified with the symbols. Vector overlays show the strength of the relationship between the predictor variables and the dbRDA axes.</p

Post-hoc correlations between continuous culture conditions and the Σ LCEFA in the % DW dataset.

<p>Panels: (a) hours light, (b) light intensity, (c) temperature, and (d) salinity for all phytoplankton groups pooled together. Each point is from a different % DW fatty acid profile (i.e., not species means), and all points are the same tone of grey, but are plotted with semi-transparency and jittering to accommodate for overplotting of points with similar values. Best-fit lines are significant (Kendall’s Tau, p<0.05).</p

Lake Washington annual and monthly phytoplankton biomass from 1961–2001.

<p>(a) Stacked barplots of annual average phytoplankton biomass, color-coded by taxonomic group, from 1961–2001. Boxplot of average total phytoplankton biomass during the (a) eutrophic years (1961–1969) prior to sewage treatment, and (b) the oligotrophic years (1975–2001) after the transition (1970–1974) to sewage treatment in Lake Washington. Abbreviations follow <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0130053#pone.0130053.g001" target="_blank">Fig 1</a>.</p

Appendix A. The model for calculating expected Daphnia fitness in the water column.

The model for calculating expected Daphnia fitness in the water column