Page 74 - E-BOOK English

Gleyic Fluvisols

Gleyic Fluvisols have a layer ≥ 25 cm or grayish brown loam, clay loam or silty clay
thick, and starting ≥ 75 cm from the mineral loam B horizon and loamy sand to sandy loam

surface soil, that has gleyic properties throughout C horizon approximately 100 cm from the surface

and reducing conditions in some parts of every soil. These soils are mottled throughout, the
sublayer. mottling in the surface layer being “inverted

Sapphaya series (Sa) is a representative gley” caused by the impounding of water and

of Gleyic Fluvisols. Sapphaya soils are formed puddling of the soil for wetland rice cultivation.
from alluvium and occur on the lower parts of Mottles in the B or C horizon are mainly dark

the stream and river levees. Relief is flat to yellowish brown, strong brown and dark brown
nearly flat. Slopes are about 0-1 percent. They in colour. Mica flakes occur throughout the

are deep soil and characterized by a dark grayish profile. Soil pH is moderately acid to
brown or very dark grayish brown loam or silty moderately alkaline (pH 6.0-8.0). Flooding is the

clay loam A horizon, overlying a stratified brown main constraint for rice production.

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