MICROMORPHOLOGICAL AND C-13 NMR CHARACTERIZATION OF A HUMIC, LIGNIC, AND HISTIC FOLISOL FROM BRITISH-COLUMBIA

The thick folic (mainly upland forest) materials (> 40 cm of accumulat ed organic material) that occur in the Coastal Western Hemlock Biogeoc limatic Zone in British Columbia have not been described with regard t o the spatial interrelationships of the soil constituents in context w ith the chemical composition of the different horizons. Micromorpholog ical assessment and solid-state C-13 NMR were used to characterize the accumulated folic materials from a Lignic Folisol (northern Vancouver Island), Histic Folisol (Prince Rupert, BC) and a Humic Folisol (Quee n Charlotte Islands, BC). Micromorphology provided information on the spatial relationships of the soil constituents and C-13 NMR provided d ata on the chemical components of the folic materials. Soil faunal act ivity, primarily from mites, was the dominant soil-forming process obs erved in the organic horizons of the Folisols, being especially promin ent in the Lignic Folisol with the breakdown of woody materials. Solid state C-13 CPMAS NMR spectra facilitated distinguishing three main ty pes of horizons: (1) Horizons derived from accumulated residues (L, Fr , and Hr) showing higher carbohydrate-like C and O-alkyl C values and lower total aromatics; (2) Horizons with advanced decomposition (Hr2, Oh1, and Hd) which were higher in alkyl C; and (3) Horizons derived fr om ligneous material (Fw and Hdw) where carbohydrate-like C was less t han total aromatic C. Implications for adequate nutrient content and f orest growth were inferred from the observed micromorphology and chemi cal composition of the folic materials.