Page 37 - World Reference Base for Soil Resources of Thailand

Land Development Department Library

Humic Acrisols

Humic Acrisols have soil organic carbon ≥

1% in the fine earth fraction as a weighted
average to a depth of 50 cm from the mineral

surface soil.

Nong Mot series (Nm) is a representative
of Humic Acrisols. Nong Mot soils are formed from

residuum and colluvium from granite and
granite derived rocks on the undulating to hilly

terrains. Slopes are about 4-35 percent. These
soils are typically found in the north of Thailand.

Drainage is well drained. Permeability is estimated
to be moderate. Runoff is slow to rapid. They are

very deep and characterized by very dark grayish
brown or dark brown loam or clay loam A horizon

overlying a reddish-brown or yellowish red to red
clay or sandy clay argillic B horizon. Soil pH is very

strongly to moderately acid (pH 4.5-6.0). Land use
limitations are low fertility and high soil erosion risk

on sloping land.

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