Page 98 - E-BOOK English

The representatives of Kastanozems in Thailand

Calcic Kastanozems

Calcic Kastanozems have a horizon in and characterized by a black, very dark gray,

which secondary calcium carbonate (CaCO ) very dark grayish brown or very dark brown
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has accumulated in a diffuse form (calcium (gravelly) clay loam or silty clay loam A horizon

carbonate occurs as impregnation of the matrix overlying a dark brown or brown, with some
or in the form of fine calcite particles of < 1 whitish marl nodules, silty clay loam, clay loam

mm, dispersed in the matrix) or as discontinuous B horizon. The C horizon with many secondary
concentrations (veins, pseudomycelia, coatings, lime nodules or marl occurs as a layer within

soft and/or hard nodules) starting ≤ 100 cm 50 cm from the surface. Soil pH is neutral
from the surface soil. to moderately alkaline in the surface and

Takhli series (Tk) is a representative moderately alkaline in the subsoils (pH 7.0-8.0).
of Calcic Kastanozems. Takhli soils are formed Although the soil is rather shallow but can be
from transported material over marly beds and used for crop production.

occur on gently undulating to undulating terrains

with slopes ranging from 2-12 percent,
covering mostly in the area of central highland
and Pasak valley. Drainage is well. Permeability

is estimated to be moderate. Runoff is slow to

medium. They are shallow calcareous soils

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