Soils Soil aeration

What is the valence of the nitrogen in NO3-?

+5

The air in soil pores almost always contains more CO2 than the atmosphere above the soil. Why is this true?

Soil microorganisms consume oxygen and release CO2 into the soil air during aerobic respiration.

Soil pores (at field capacity) contain only water.

false

The great bulk of gaseous interchange between the soil pores and the atmosphere occurs by mass flow of the concerned gases.

false

Which of the following is (are) considered necessary features for an area to be delineated as a wetland?

hydric soils wetland hydrology hydrophytic (wetland) plants

Redox potential is a measure of ________.

the tendency for electrons to be transferred from one substance to another

After O2 has been consumed in a waterlogged soil, alternative electron acceptors such as nitrate (NO3-) can be utilized by adapted microorganisms.

true

An abundance of macropores in soils helps assure an abundance of oxygen in the soil.

true