Fig. 3. Polycyclic aromatic hydrocarbon (PAH) spectra of the Oa horizon from the control plots, of the wood ash, and of the Oa horizon 1 yr after the wood ash application.
Fig. 3. Polycyclic aromatic hydrocarbon (PAH) spectra of the Oa horizon from the control plots, of the wood ash, and of the Oa horizon 1 yr after the wood ash application.