soil map units where Tv Tu’avao soils is dominant
Soil properties
| Property | Value |
|---|---|
| Geographic distribution | Niuatoputapu |
| Landscape position | Form on alluvial materials in south and southwest of island. |
| Soil parent material | - |
| Slope | Flat to undulating (0-5°) |
| Surface outcrops | - |
| Brief soil profile description | 0-30 cm Very dark grey friable sandy loam; 30-90 cm Very dark greyish brown to dark brown friable sandy loam; >90 cm Yellowish brown firm sandy loam. |
| Soil profile texture | - |
| Minimum effective rooting depth | 100 cm |
| Soil pH (acidity) | Slightly alkaline |
| Salinity | - |
| Soil fertility under natural conditions | Organic carbon (C) and nitrogen (N) values low; total phosphorus (P) and phosphorus (P) very high; sulphur (S) medium; Base saturation (%) very high; calcium (Ca) high; potassium (K) and sodium (Na) values medium. |
| Soil moisture regime | - |
| Susceptibility to drought | - |
| Soil drainage | Somewhat excessively drained |
| Susceptibility to waterlogging | Never Waterlogs |
| Susceptibility to flooding | Never Floods |
