The June 8 edition of the Kansas State University Extension Agronomy e-Updates newsletter takes a look at nitrogen additions, nutrient cycling and water management with cover crops. The newsletter notes that cover crops play many potential roles, such as fixing carbon as a source of additional crop residue and soil organic matter, trapping residual nitrogen that may remain after a crop is harvested, fixing nitrogen for use by subsequent cereal or forage crops.
The newsletter also features an article entitled, “Nitrogen in the Soil: Additions, Losses and the Impact on Crops,” which discusses the three primary pools of nitrogen that are present in soils:
· An inorganic nitrogen pool comprised primarily of ammonium and nitrate. The inorganic nitrogen pool is readily available to crops.
· A dynamic pool of organic materials, including living organisms, plant roots and crop residues which are actively undergoing decomposition and transformation.
· A stable, recalcitrant pool of organic materials produced from the decomposition of plant and animal residue and referred to as soil organic matter.
Read the nitrogen articles online at http://www.agronomy.ksu.edu/doc3966.ashx.