Formation of melanic epipedons under forest vegetation in the xeric moisture regime of northern California

Molecular features of organic matter in diagnostic horizons from andosols as seen by analytical pyrolysis

“…Our findings suggest a high-performace organo-mineral sequestration of aliphatic substances in andosols whereas classical hypotheses of concentration or aromatic structures should represent alternative, well-publicised, local feature of andosols affected by fires in the past [58][59][60][61].…”

Nature, properties and function of aluminum–humus complexes in volcanic soils

“…This indicates that C3 plants, including tree vegetation, are also an important source of humic materials in melanic epipedons (Shindo et al, 2005;Hiradate et al, 2006). Furthermore, Inoue et al (2001Inoue et al ( , 2006 and Takahashi et al (1994) showed that C4 plants were not necessary for formation of melanic epipedons. In addition to these grass and tree vegetation types, pteridophyte vegetation, such as bracken fern (Pteridium aquilinum), has been shown to preferentially form Al-humus-rich melanic or melanic-like surface horizons (Birrell et al, 1971;Johnson-Maynard et al, 1997;Leamy et al, 1980;Lowe and Palmer, 2005).…”

“…In addition to these grass and tree vegetation types, pteridophyte vegetation, such as bracken fern (Pteridium aquilinum), has been shown to preferentially form Al-humus-rich melanic or melanic-like surface horizons (Birrell et al, 1971;Johnson-Maynard et al, 1997;Leamy et al, 1980;Lowe and Palmer, 2005). Takahashi et al (1994) documented the presence of high concentrations of charred materials across a range of melanic epipedons in northern California. A subsequent analysis of these samples indicated that charcoal comprised up to 20% of the total organic C pool (Dahlgren, unpublished data).…”

Natural range of variation for yellow pine and mixed-conifer forests in the Sierra Nevada, southern Cascades, and Modoc and Inyo National Forests, California, USA

“…Presence of melanic epipedons (humus) in forest andisols has traditionally been ascribed to periods in which the soils supported grassy vegetation, but phytolith analysis of the California YPMC soils showed very little to no grass component could have been present during the formation of the soils, i.e., over many centuries. According to Takahashi et al (1994), the occurrence of frequent fire in their study forests may have been the key factor in forming melanic epipedons in the andisols they studied.…”