Figure legends
Figure 1. a) Experimental program illustrating timing for the three experimental phases and the sequencing of the eight reactors. The temperature profiles for Phase III are based on historical climate data in Fort Myers Florida. The Extreme Profile is based on summer temperatures only; the average profile is based on annual average. Both involve hourly temperature variations in the reactors. The Constant Profile has constant values on a 12-12 cycle based on annual day and night averages. b) Photobioreactor setup for cultures in Phase I where Reactors A, B and C, D were cultivated at 20 °C and (b) Reactors E, F and G, H were cultivated at 35 °C. Dye-1 and Dye-2 were the dummy reactors used for monitoring temperature, and reactors W-1 and W-2 were connected to the reactor exhaust and used as waste collectors due to minor foaming and evaporation loss. Reactors are brought outside of the incubator for sampling and photography.
Figure 2. OD (750 nm) results for cultures in three different phases (a) AB and CD and (b) EF and GH at various temperature treatments. Results shown are the average of two determinations with error bars showing the range of values. Temperature conditions for the various phases are shown.
Figure 3. Late-phase average biomass productivities ofArthrospira platensis at various temperature treatments in three phases: Phase I temperature were 20 and 35 °C; in Phase II temperature were 20, 30 and 35 °C and in Phase III 31 °C (CtSP), 32 °C (AvSP) and 36 °C (ExSP), where temperature designations are the average daytime values. Error bars are +/- one standard deviation for the averages over multiple days of semi-continuous operation.
Figure 4 . Representative whole cell (WC) spectra of cultures at different temperature treatments in the three phases of the experiment (a) Phase I at 20 °C (A and C) and 35 °C (E and G), (b) Phase II at 35 °C (A), 30 °C (C) 20 °C (E) and 30 °C (G), and (c) Phase III with Extreme Summer, ExSP (A), Average Summer, AvSP (C) and Constant Summer, CtSP (G). The absorbance values are normalized to 1 gDW L-1.
Figure 5. PC and Chl-a content (%, DW) in the three phases of the experimental plan at different temperature conditions. Experiments were performed in duplicate.
Figure 6 . Photosynthesis irradiance (PI) response curves (measured at 30 °C) for the algal cultures at different temperature treatments in (a) Phase II on day 27, A-35 °C, C-30 °C, F-20 °C, and H-35 °C, and (b) Phase III on day 43, AB-ExSP, CD and EF-AvSP and GH-CtSP.
Figure 7 . Experiment results of biomass productivity in comparison to the productivity model simulation. The productivity model parameter set, representative of the PI database at 30 °C, is [α, Ek, R0] = [0.061 fixed C/photon, 240 µE/m2-s, 0.1 µmolC/mgChl.a-min].
Figure 1