soil map units where Eh Naninimai series is dominant
Soil properties
Property | Value |
---|---|
Geographic distribution | Tarawa, Abatao |
Landscape position | Usually occurs on relatively higher and stable surfaces |
Soil parent material | coralline sand and gravel |
Slope | Flat (0 - 3°), some microtopography caused by abandoned Cyrtosperma pits. |
Surface outcrops | Rounded coral stones on surface. |
Brief soil profile description | A deep well developed A horizon. Topsoil depth varies from 30-60 cm with structures varying from weakly to moderately developed granular. The lower portions of the A horizon usually have little structure. The coarse fragment content of the subsoil varies from 0-10% |
Soil profile texture | Typically shows a thick (> 25 cm) black or very dark brown sandy loam topsoll wlth appreciable structure overlying light coloured sand with small but variable amounts of coarse material. |
Minimum effective rooting depth | 30-60 cm |
Soil pH (acidity) | Alkaline and highly calcareous; pH values in water are usually greater than 8 |
Salinity | - |
Soil fertility under natural conditions | Organic carbon and nitrogen levels are usually high in the A horizon but very low in the subsoil; total and available phosphorus are generally low; CEC is moderate in the A horizon, low in the subsoil and free lime is found throughout the profile; exchangeable magnesium is moderate but potassium is very low; phosphate extractable sulphate levels are moderate in topsoils. |
Soil moisture regime | Ustic |
Susceptibility to drought | Dries out in dry periods. |
Soil drainage | Excessivly drained |
Susceptibility to waterlogging | Not susceptible to waterlogging |
Susceptibility to flooding | Never floods |