Page 81 - E-BOOK English

Soil classification

WRB: Thionic Gleysols
Soil taxonomy: Very-fine, mixed, semiactive, acid, isohyperthermic Sulfic Endoaquepts

Soil series: Rangsit series (Rs)

Profile description

 0-5 cm (Apg) Very dark gray to very dark grayish
brown (10YR 3/1-2) clay; common fine distinct
yellowish brown (10YR 5/8) mottles mainly along
root channels; weak medium and coarse breaking
to medium and fine subangular blocky structures;
firm, sticky, plastic; many very fine roots; very
strongly acid (field pH 5.0); gradual, slightly wavy
boundary.
 15-30/35 cm (Bg1) Black (10YR 2/1) clay; many
fine, medium distinct yellowish brown (10YR 5/8)
and few fine prominent red (2.5YR 4/8) mottles;
weak to moderate breaking to fine angular blocky
structures; firm, sticky, plastic; few slickensides;
few very fine roots; very strongly acid (field pH
4.5); gradual, wavy boundary.
 30/35-49 cm (Bg2) Mixed very dark grayish brown
(10YR 3/2) and grayish brown (10YR 5/2) clay; many
medium and coarse prominent red (10R 4/8), fine
and medium distinct yellowish brown (10YR 5/8)
mottles; moderate medium and fine angular blocky
structures; firm, sticky, plastic; few very fine roots;
common pressure faces and slickensides; very strongly acid (field pH 4.5); gradual, smooth boundary.

 49-59/65 cm (Bjg1) Brown (7.5YR 5/2) clay; few small inclusion of dark A materials; many medium and
coarse prominent red (2.5YR 4/8) and dark red (7.5R 3/8) and many fine pale yellow (2.5Y 7/4) (jarosite
mottles) and few fine yellowish brown (10YR 5/8) mottles; moderate medium and fine angular blocky
structures; firm, sticky, plastic; few very fine roots; common pressure faces and slickensides; very
strongly acid (field pH 4.5); clear, wavy boundary.
 59/65-110 cm (Bjg2) Brown (7.5YR 5/2) clay; many medium and coarse pale yellow (2.5Y 8/6)
(jarosite) and few fine distinct yellowish brown (10YR 5/8) mottles as vertical streaks; moderate
prismatic breaking to angular blocky structures; firm, sticky, plastic; few slickensides; very strongly
acid (field pH 4.5).
 110-160 cm (Cjg) Brown (7.5YR 5/2) half ripe clay; common medium and coarse distinct yellowish brown
(10YR 5/8) and few medium pale yellow (2.5Y 8/6) mottles; very strongly acid (field pH 4.5).

 160-190+ cm (Cg) Dark greenish gray (5GY 4/1) and dark gray (5Y 4/1) half ripe clay; moderately
acid (field pH 6.0).

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