Question

Flooded soils generally develop a gley (bluish gray) color. This is a result of ____.

A. Reduction of SO4^2- to S^2-

B. Reduction of NO3- to NO2-

C. Reduction of Fe(lll) to Fe(ll)

D. Decomposition of organic matter

In air dry soils, merely hygropscopic water exists. True or false

Drainage can only remove gravitiational water, but not capillary water. true or false

Answer 1

Ans 1. C reduction of Fe III to Fe II(ferrous).

Soil that has a high water content will have less air in the soil, specifically less oxygen.

Ans 2. True

In air-dry soils the adsorptive (i.e., hygroscopic) components dominate the wet-bonding forces because the soil is too dry for liquid bridge bonding (i.e., capillarity) to exist.

Ans 3. True

When all the gravitational water is drained away only micro- pores or capillary pores are filled with water.