Fig 4. Relationship between canopy reflectance and floristic composition or soil cation concentrations.

Panels display reflectance spectra for transects from the Pastaza-Tigre (“PT”; a,c) or Curaray (“CU”; b,d) study areas. (a, b) Mean spectra for transects from the Pebas Formation clustering group (blue) or Nauta Formation clustering group (red), such that color-coding matches Fig. 2b. Blue and red lines indicate mean spectra for all transects in the clustering group, and semi-transparent areas indicate ±1 standard deviation intervals. (c,d) Mean spectra for each of the four cation concentration quartiles. Color-coding matches that in Fig. 2d, such that red indicates the first (bottom) quartile, orange the second, green the third, and blue the fourth (top).