Fig. 7. Chromatographic trace of phenolic acids (PAs) following alkaline extraction of the humic acid isolated from the Webster soil under native prairie vegetation. The identities of the PA compounds are given in Table 1.
Fig. 7. Chromatographic trace of phenolic acids (PAs) following alkaline extraction of the humic acid isolated from the Webster soil under native prairie vegetation. The identities of the PA compounds are given in Table 1.