Manure Phosphorus and Surface Water Protection II: Field and Management Factors Glossary

This water P fraction, also refer to algal-available P, is a combination of dissolved P plus the estimated portion of P to be released from sediment P within a short time, e.g. 45 hours, after the particles enter surface water.

Chemical extraction method developed by R.H. Bray and L.T. Kurtz in 1945 to estimate the availability of P to plants.

Any crop grown to provide soil cover and prevent soil erosion by wind or water.

Any crop grown to provide soil cover and prevent soil erosion by wind or water.

This water P fraction, a near equivalent with dissolved reactive P, is readily available to aquatic plants and animals.

This soil P fraction is typically accounts for less than 1% to less than 5% of the P in soils, and is less tightly bond than stable P. Some labile P, as well as solution P, is measured with agronomic soil tests.

Chemical extraction method developed by A. Mehlich in 1984 to estimate the availability of P to plants.

The soil isn’t broken except for planting and maybe for some fertilization.

An extractant used for soil testing of neutral and calcareous soils that estimates the capacity of a soil to supply available P.

The portion of precipitation or irrigation on an area that does not infiltrate but, instead, is discharged from the area. That which is lost without entering the soil is called "surface runoff."

This water P fraction, also referred to as particulate P, often is the greatest fraction in water bodies. It consists of organic and inorganic sediments. Its not available to most aquatic plants and animals, but phosphatase producing algae can cause organic sediment P to become available.

A collection of individual cores from a known area.

A measure of the availability of solution and labile soil P to a crop.

This soil P fraction is typically accounts for less than 1% of the P in soils and is readily available to plants.

This soil P fraction is also called non-labile P. It accounts for most of the P in soils, typically more than 95% of the total, and includes tightly bond P in secondary and primary minerals and in organic forms.

A measure of the availability of solution and labile soil P to a crop.

Water movement in the soil.  Pore space in soil is the conduit that allows water to infiltrate and percolate (downward movement of water through the soil).