Nitrous Oxide Emission from Soils

Nitrous oxide (N2O) constitutes only 350 parts per billion (ppb) of the atmosphere. Its production by biochemical processes in soils has long been recognized (Delwiche, 1981; Payne, 1981a, b). However, recent concern about the involvement of N2O in promoting destruction of the stratospheric ozone layer, which protects the biosphere from harmful ultraviolet radiation (Crutzen, 1970, 1971, 1974, 1981; Johnston, 1971, 1977; CAST, 1976; McElroy et al., 1977; Liu et al., 1977), and also the concern that the increased N2O may contribute to the “greenhouse effect” caused by increased CO2 concentration (Yung et al., 1976), have resulted in extensive research on how N2O emissions are affected by fertilizer N usage for meeting food, feed, and fiber requirements of the world (Delwich, 1981; Payne, 1981b; Keeney, 1982; Firestone, 1982; Freney and Simpson, 1983).