Figure 2: Classification of the m/z peaks into specific biomolecular classes using a van Krevelen diagram.

FO and FY represent old-growth forest and young plantation stands, respectively. n values represent the number of lysimeters which collected soil water. The average values are shown for soil water samples with n = 2 or n = 3. See Methods for the abbreviations of groundwater and biomolecular classes and see Figures S1 and S2 for variations in the number of m/z peaks for each biomolecular class in soil water samples.