in panel D. (F) Relative distribution of phase angles between fluctuations in water level and nitrate concentration. The phase angle distributions in (C) and (F) are based on the complete time series (2001–2009). (TIF) Figure S12 Coherence between fluctuations in nitrate concentration, tidal range and salinity on a daily time scale. (A) Time series of nitrate concentration (thick purple line) and tidal range (thin blue line) on a daily time scale during spring of 2007. (B) Wavelet coherence spectrum of the two time series in panel A. Color coding indicates the coherence of the two time series. Arrows indicate the phase angle between fluctuations of the two time series. See the legend of Fig. 3 for further explanation of wavelet spectra. (C) Relative distribution of phase angles between fluctuations in nitrate concentration and tidal range. (D) Time series of nitrate concentration (thick purple line) and salinity (thin blue line) on a daily time scale. 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Mar Ecol Prog Ser 196: 59–73, doi: 10.3354/meps196059. PLOS ONE | www.plosone.org 13 November 2012 | Volume 7 | Issue 11 | e49319