Figure 3. Effects of reaction with mineral surfaces on molar absorptivity (e) of dissolved NOM as measured by UV absorbance (280 nm) normalized by DOC. Grey band represents the mean ± 95% confidence interval for e of unreacted NOM. Oak FFL NOM is used for comparison across mineral types, whereas the effect of FFL source (oak versus pine) is assessed using goethite as a common adsorbent.