Soil Moisture and Temperature Regimes

In this post we will know about the soil moisture and temperature regimes.

Soil Moisture Regimes

A soil moisture regimes refers to the presence or absence of either water water saturated conditions or plant-available soil water. There are several moisture regime classes that are used to characterize soils.

• Aquic: Soil is saturated with water and virtually free of gaseous oxygen for sufficient periods of time for evidence of poor aeration.
• Udic: Soil moisture is sufficiently high year round in most years to meet plant needs. This regime is common for soils in humid climatic regions and characterizes about one third of the world wide land area.
• Ustic: Soil moisture is intermediate between Udic and Aridic regimes and there is some plant available moisture during growing season.
• Aridic: The soil is dry for at least half of the growing season and moist for less than 90 consecutive days. The term torric is used to indicate the same moisture condition in certain soils.
• Xeric: This type of regime is found in typical Mediterranean type climates with cool, moist winters and warm, dry summers.

Soil Temperature Regimes

They are generally cryic, frigid, mesic and thermic and are used to classify soils at some of the lower levels in Soil Taxonomy. These regimes are based on mean annual soil temperature, mean summer temperature and the difference between mean summer and winter temperature.

Reference:

Brady, N.C. and Weil, R.R., The nature and properties of soil. 13th Edition.