Which soil has more air content?

Bavarian State Office for
environment

Soils are criss-crossed with pores that transport liquids and gases. Mostly the pores are with Leachate, soil solution or air filled. Which pore system develops depends heavily on the soil matrix.

Soil matrix. Water. Air.

Soil scientists call soil matrix the solid components of the mineral and organic soil substance.

Their composition determines how much water and air the soil can potentially absorb could. How much the soil is currently ingested Hasdepends on the vegetation, weather and hydrological conditions at a location.

Where and how does water move?

Water is involved in almost all soil formation processes. So soil scientists investigate where and how water moves in soils. For example, water is in the wide and narrow Coarse pores (≥ 0.01 millimeters) freely movable. In the vast expanses, water seeps away particularly quickly. In contrast, water in the narrow, coarse pores remains available to plants for a longer period of time.

The bond between water and soil matrix decreases from the Central pores (≥ 0.0002 to <0.01 millimeters) up to the Fine pores (<0.0002 millimeters) too much. In the fine pores, the water is no longer available for plants (dead water).

Water and air balance in soils

Soil scientists describe the water and air balance of soils mostly with three parameters:

  • The Air capacity (SC) is a measure for the supply of plant roots with oxygen and indicates the air content of a soil with field capacity.
    LK = large pores
  • As Field capacity (FK) is the term used to describe the total amount of water that a soil can hold against gravity.
    FK = narrow coarse pores + medium pores + fine pores
  • Just the water of the Usable field capacity (nFK) is available at field capacity for plants. In the fine pores, the water is no longer available for plants (dead water).
    nFK = narrow coarse pores + medium pores

Additional information

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