Molecular Signatures of Humic Acids from Different Sources as Revealed by Ultrahigh Resolution Mass Spectrometry

Figure 3

Respective DBE-H/C diagrams from (a) humic acids from Jiufeng forest soil, (b) humic acids from Suwannee River, and (c) humic acids from leonardite. Nor_int is the normalization of the intensity of each molecule.

(a)

(b)

(c)