| Definition of Ferralsols - Having a ferric horizon at some depth between 25 and 200 cm from the soil surface, and - Lacking a nitic horizon within 100 cm from the soil surface, and - Lacking an argic horizon with 10 per cent or more water-dispersible clay within 30 cm from its upper boundary unless the soil material has geric properties or contains more than 1.4 per cent organic carbon | ||||||||
| Connotation | Parent materials | Profile development | ||||||
| Red and yellow tropical soils with a high content of sesquioxides from L. Ferrum-iron. | Strongly weathered materials, on old strong geomorphic surfaces, more in weathering material from the basic rock than in siliceous material. | ABC profiles. Deep and intensive weathering has resulted in a high concentration of residual, resistant primary minerals alongside sesquioxides and well-crystallized kaolinite. The mineralogy and pH explain the yellowish (goethite) or reddish (hematite) soil colours. | ||||||
| Geological description of the site and parent material | ||||||||
| Age | Lithology | Other information | ||||||
| Proterozoic | Precambria/Oregenic Belt | Parent rocks | ||||||
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| The System (Usagaran) comprises sedimentary, volcanic rocks and gneisses, amphibolites and lenses of granulites | Highly metamorphosed | ||||||
| Hydro-physical properties of the soil of the study area | ||||||||
| Depth (cm) | Clay (%) | Sand (%) | ρb (g/m3) | θPWP (%) | θFC (%) | θSAT (%) | ||
| 0 - 30 | 41.1 | 49.2 | 1.44 | 11.9 | 22.5 | 44.0 | ||
| 30 - 60 | 40.1 | 52.2 | 1.35 | 16.1 | 24.0 | 43.6 | ||
| 60 - 90 | 40.1 | 55.2 | 1.35 | 15.5 | 26.6 | 45.4 | ||
| 90 - 120 | 32.1 | 59.2 | 1.37 | 15.4 | 26.2 | 45.3 | ||