2). Fig. 7 R 2 for regressions of F v/F m(λex,λem) of simulated

communities against F v/F m(470,683) and F v/F m(590,683) of respectively algal and cyanobacterial subpopulations. These plots represent cross sections of the excitation–emission regression matrix of Fig. 6: a the 683-nm emission line, b the 470-nm excitation line, and c the 590-nm excitation line. Key excitation–emission BIX 1294 cost pairs are indicated by the numeric markers corresponding to Figs. 6 and 8 The data underlying the optimal excitation/emission pairs identified from Figs. 6 and 7 are presented in Fig. 8 with corresponding regression statistics. Figure 8a confirms that community F v/F m(470,683) is strongly driven by the algal F v/F m and was FHPI concentration highly insensitive to the fluorescence of the cyanobacteria in the simulated communities. Only the case for equal Selleck Mocetinostat absorption in the algal and cyanobacterial subpopulations is shown here, but when the community composition was skewed to 90% in favour of the cyanobacteria, community F v/F m(470,683) remained a good (relative error <10%) predictor of algal F v/F m(470,683) in 92% of cases. The fluorescence emission of the cyanobacterial

fraction was too low at this excitation/emission pair to influence community variable fluorescence, even when mixed with algal cultures of low (variable) fluorescence. Fig. 8 Case plots underlying the linear regression analyses of community F v/F m(λex,λem) versus algal and cyanobacterial F v/F m(470,683) and F v/F m(590,683), respectively. a–c correspond to the key excitation–emission pairs highlighted with numerical markers in Fig. 6. a F v/F m(470,683), sensitive to algal but not cyanobacterial F v/F m, b F v/F m(590,683), with stronger correspondence to cyanobacterial compared to algal F v/F m and c F v/F m(590,650), strongly related to cyanobacterial F v/F m(590,683) >0.4. Colours and symbols correspond to Fig. 7, drawn black lines mark unity. The discrete distribution of the subcommunity F v/F m values is caused by

the limited number of cultures used to simulate community F v/F m matrices Under red–orange illumination centred at 590 nm (Fig. 8b) we note a better correlation of community and cyanobacterial F v/F m (R 2 = 0.54). Farnesyltransferase The relatively low slope and high offset of this regression were clearly caused by the inclusion of cases where cyanobacterial subpopulations with low F v/F m were mixed with algae with higher F v/F m, a result of a wider spread of F v/F m in the cyanobacterial cultures compared to the algae (Fig. 3). The regression results for the algal fraction under emission at 590 nm were clearly worse with R 2 = 0.18. The variable fluorescence originating from PBS pigments (F v/F m(590,650)) was lower than F v/F m(590,683) while the relation between community and cyanobacterial F v/F m was strong for cyanobacteria cultures with F v/F m >0.42 (Fig. 8c).