Soil Resources of European Volcanic Systems



Volcano di Vico - November 1998

Date of description: 21-11-1998

Authors: A.G. Jongmans and F. van Oort

Location: Italy, North of Rome, Volcano di Vico, Caldera of San Matteo

Altitude: 722m

Map number and Co-ordinates: U.T.M. 33T TG 644 934

WRB (2001): Fulvi-Silandic Andosol (Dystric)
ST (1999): Ashy, amorphic mesic Eutric Pachic Fulvudand


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Soil Climate: Mesic temperature regime, ann. temp. 11.8o C; Udic moisture regime, ann. prec. 1670 mm

Topography: Steeply dissected

Landform: Hill, Volcano

Land element: Slope

Position: Upper slope

Slope: Steep, 30-60%

Form: Straight

Landuse/Vegetation: Forest: dominantly oak (quercus cerris) with maple, blackberry, ivy (hedera); bracken, honeysuckle, grass.

Human influences: Forest lane cut, a road is situated 20 m above the profile pit

Patent material: Lava, tephritic-phonolitic with leucite

Effective soil depth: Deep

Erosion: Frequently fresh rock fragments (stones) at the soil surface

Drainage class: Well drained

Internal drainage: Rapid

External drainage: Rapid runoff

Moisture conditions: Slightly moist


O:      0-2 cm: Dominantly partly decomposed organic matter with fresh litter on top; abrupt and smooth to:

Ah1:   2-10 cm; very dark brown (10YR 2/2); silt loam, very few, fine gravel, partly altered; strong, very fine angular blocky structure; very friable; biopores not detectable; many fine, few medium roots; clear and smooth to:

Ah2:   10-27 cm: black (7.5YR 2/0); silt loam, very few fine to coarse gravel, both fresh and weathered; 20% subrounded pockets with strong fine granular structure, rest groundmass has no macro structure; friable; few fine biopores; many fine, few medium and coarse roots; clear and smooth to:

Ah3:   27-45 cm: very dark brown (10YR 2/2); silt loam, few fine to coarse fresh and altered gravel, subrounded; very weak, fine, subangular blocky structure, pockets with strong fine granular structure; friable; common fine biopores; many very fine, few medium and coarse roots, clear and smooth to:

Bw1:  45-72 cm; dark yellowish brown (10YR 4/6) subrounded pockets of 1-2 cm consisting of Ah3 material; sandy loam, common, fine to coarse gravel, partly weathered showing weathering rinds; weak, fine subangular structure, locally pedotubules filled with organo-matric faecal pellets; friable; many fine biopores; many fine, few medium and coarse roots; gradual and smooth to:

Bw2:  72-107/142 cm; yellowish brown (10YR 5/6); sandy loam, many fine to coarse subrounded gravel, partly weathered; weak fine subangular blocky structure; friable; many fine biopores; common fine, few, medium and coarse roots; clear and wavy to:

C:      107/142-182 cm; Dark coloured, fine textured, blocky lava with vacuoles filled with white leucite crystals / zeolites; the lava is breakable into smaller entities (physical weathering); vertical elongated fissures up to 5 cm, occur , filled with brownish yellow (10 YR 6/6) loamy sand;, in the fissures fine and medium roots are present.



WRB (2001): possibly fulvic horizon (no figures on the melanic index; fulvic is assumed because of forest vegetation); andic horizon (0-105 cm); mean Sio 1.65%; BS < 50% in at least some part between 20 and 100 cm, but > 20% in all parts between 20 and 100 cm:

Fulvi-Silandic Andosol (Dystric)

ST (1999): possibly melanic horizon (no melanic index determined; chosen for Fulvudand because of forest vegetation); andic soil properties (0-105/140 cm); mean Sio 1.65%, mean Feo 0.71% between 0 and 100 cm, 8x Sio + 2x Feo > 5, 8x Sio > 2x Feo (Santiago figures):

Ashy, amorphic, mesic Eutric Pachic Fulvudand

Last modified 30 April 2004 by EG