Ecophysiological performance of an urban strain of the aeroterrestrial green alga Klebsormidium sp. (Klebsormidiales, Klebsormidiophyceae)

Figures & data

Fig. 1. Growth rates (µ d⁻¹) as a function of photon fluence density (a) and of salinity (b) in Klebsormidium sp. (n = 4, mean value ± SD). In vivo growth was measured using a fluorometer according to the technique of Gustavs et al. (2009b ). Significance of differences among the treatments was calculated by one-way ANOVA (P < 0.001). Different letters represent significant differences among the photon fluence rates as revealed by Tukey's post hoc test. psu, practical salinity units.

Fig. 2. Photosynthetic oxygen evolution as function of increasing photon fluence densities in Klebsormidium sp. (n = 3, mean value ± SD) according to the method of Remias et al. (2010). The dashed line represents a fitted curve of the data measured based on the photosynthetic equation of Webb et al. (1974).

Fig. 3. Changes in photosystem II efficiency (F _v/F _m: optimum quantum yield) of Klebsormidium sp. (n = 5, mean value ± SD) after 72 h exposure to a range of salinities. Significance of differences among the treatments was calculated by one-way ANOVA (P < 0.001). Different letters represent significant differences among the salinities as revealed by Tukey's post hoc test. psu, practical salinity units.

Fig. 4. Changes in sucrose concentration (µmol g⁻¹ dry weight) of Klebsormidium sp. (n = 4, mean value ± SD) after 72 h exposure to a range of salinities. Significance of differences among the treatments was calculated by one-way ANOVA (P < 0.01). Different letters represent significant differences among the salinities as revealed by Tukey's post hoc test. psu, practical salinity units.

Fig. 5. Changes in photosystem II efficiency (F _v/F _m: optimum quantum yield) of Klebsormidium sp. (n = 4, mean value ± SD) during 2 h desiccation under ambient room temperature conditions (c. 22°C) followed by 48 h recovery after rehydration with stock culture medium. Significance of differences among the treatments was calculated by one-way ANOVA (P < 0.001). Different letters represent significant differences among the time points as revealed by Tukey's post hoc test.

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