Results of the principal component analysis (PCA) of environmental and biotic variables in the temperature gradient.

<p>The ordination plot summarizes the variation of the environmental and biotic variables across the 121 samples (indicated by site and date) included in the fourth-corner analysis of the temperature gradient. Temperature = surface water temperature at each sampling site, Seastemp = surface water temperature at Site G, Spatanom = spatial surface water temperature anomaly, PAR = daily average solar irradiation (photosynthetically active radiation) at the water surface, DIN = dissolved inorganic nitrogen, DIP = dissolved inorganic phosphorus, DSi = dissolved inorganic silicate, N:P = molar DIN:DIP ratio, FLOW = water movement flow factor cf. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0109993#pone.0109993.s005" target="_blank">Table S5</a>, MPB = microphytobenthic biomass, Maccov = macroalgal cover cf. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0109993#pone.0109993.s005" target="_blank">Table S5</a>, Fauna = invertebrate macrofauna density, Richness = number of diatom taxa in 1000 valves.