Submitted to: Encyclopedia of Soils in the Environment
Publication Type: Book / Chapter
Publication Acceptance Date: 11/10/2003
Publication Date: 10/27/2004
Citation: Martens, D.A. 2004. Denitrification. In: E Hillel, D. (Ed.). Encyclopedia of Soils in the Environment. Vol. 1. Oxford, U.K.: Elsevier Ltd. pp. 378-381.
Interpretive Summary: Nitrogen (N) losses as gaseous forms via denitrification can limit N plant use efficiency and the generation of nitrous oxide by this process can also impact potential global climate change by contribution to the greenhouse effect. The manuscript reviews the denitrification processes for an on-line reference that will provide interested readers a first contact to the denitrification subject with additional suggestions for further reading. The work will include a major encyclopedia reference source covering the wide spectrum of soil science and as such will provide a valuable reference source for continued soil research on greenhouse gas emissions.
Technical Abstract: Denitrification is the major biological process through which plant available soil N is returned to the nonavailable atmospheric N pool as N2O and N2. Despite the central role of microbial denitrification for N cycle regulation of plant available N, this process remains one of the least quantified mechanism(s) of soil N transformation. Rates of N loss from agricultural soils through denitrification can vary tremendously, ranging from 0 to 70% of applied N. In the USA, N2O from the use of N fertilizers in 1998 accounted for 45% of the total N2O emission budget.