soils

Infiltration

Water entering the soil.

Percolation

Water movement through the soil.

Drainage

Movement of water out of soil.

Flooding vs. Ponding

Flooding is unstable, while ponding is a stable condition.

Ponding

Water perched on top of the soil.

Epi Saturation

Water that comes from above.

Endo Saturation

Water that accumulates from within.

Pedology

The study of pedogenesis.

Pedogenesis

The study of soil formation combined with geomorphology, involving building and destroying processes.

Soil Skeleton

Consists of fine sand or larger particles.

Soil Plasma

Clay, organic matter, silts; the components transported by water.

Eluviation

The process of destroying or leaving behind materials, resulting in a net loss.

Illuviation

The process of building up materials, resulting in a net gain.

Leaching

The removal of materials completely from the soil profile due to eluviation.

Mollisols

Soils found in prairie regions, characterized by higher mineral content, deep A horizons, and melanization.

Histosols

Soils that are high in organic matter, typically found in peat bogs.

Humification

The process involving organic matter that leads to the formation of humus.

Organic Matter Accumulation in Peat Bogs

Result of water sitting in a ponded environment, leading to 100% organic matter accumulation in wet and cold environments.

Melanization

The development of dark organic matter coatings on soil peds and minerals, causing a dark color in the horizon.

Soil Water

The main agent transporting solids and ions within the soil.

Adsorbed Water

Water held by adhesive forces between water molecules and a specific surface.

Absorbed Water

Water held by cohesive forces to absorbed water, maintained in small pores.

Capacity of Water

The total amount of water held in soil, including both adsorbed and absorbed water.

Gravimetric Water Content of Soil

Calculated as: wg = (Mass of moist soil - Mass of oven-dry soil) / Mass of oven-dry soil.

Soil Bulk Density

Calculated as: pd = Mass of oven-dry soil / Soil volume.

Soil Water Potential

A combination of potential energies that govern water movement in soil.

Matric Potential

The attraction between soil particles and water, measured in bars, required to remove water from soil.

Gravitational Potential

The movement of water downward due to gravity in saturated soils.

Field Capacity

The water content of soil when gravitational water movement ceases.

Permanent Wilting Point

The point at which plants cannot extract water, measured at 15 bars.

Hygroscopic Water

Water that is held tighter than 15 bars, only adsorbed.

Water Potential Dependency

Water potential is highly dependent on soil texture.

Silts

Soil texture that holds the most plant-available water.

Mineralogy

The study of inorganic materials found in soils, which are naturally occurring.