000			02323nab|a22003497a|4500
999			_c62805 _d62797
001			62805
003			MX-TxCIM
005			20211006085216.0
008			200624s2005||||xxk|||p|op||||00||0|eng|d
022			_a1365-2486 (Online)
024	8		_ahttps://doi.org/10.1111/j.1365-2486.2005.01040.x
040			_aMX-TxCIM
041			_aeng
100	1		_aMcSwiney, C.P. _916749
245	1	0	_aNonlinear response of N2O flux to incremental fertilizer addition in a continuous maize (Zea mays L.) cropping system
260			_aUnited Kingdom : _bWiley, _c2005.
500			_aPeer review
520			_aThe relationship between nitrous oxide (N2O) flux and N availability in agricultural ecosystems is usually assumed to be linear, with the same proportion of nitrogen lost as N2O regardless of input level. We conducted a 3‐year, high‐resolution N fertilizer response study in southwest Michigan USA to test the hypothesis that N2O fluxes increase mainly in response to N additions that exceed crop N needs. We added urea ammonium nitrate or granular urea at nine levels (0–292 kg N ha−1) to four replicate plots of continuous maize. We measured N2O fluxes and available soil N biweekly following fertilization and grain yields at the end of the growing season. From 2001 to 2003 N2O fluxes were moderately low (ca. 20 g N2O‐N ha−1 day−1) at levels of N addition to 101 kg N ha−1, where grain yields were maximized, after which fluxes more than doubled (to >50 g N2O‐N ha−1 day−1). This threshold N2O response to N fertilization suggests that agricultural N2O fluxes could be reduced with no or little yield penalty by reducing N fertilizer inputs to levels that just satisfy crop needs.
546			_aText in English
650		7	_aAgriculture _gAGROVOC _2 _91007
650		7	_aAmmonium _2AGROVOC _98774
650		7	_aDenitrification _2AGROVOC _915862
650		7	_aMaize _gAGROVOC _2 _91173
650		7	_aNitrogen _2AGROVOC _92912
650		7	_aNitrogen fertilizers _2AGROVOC _91190
650		7	_aNitrates _2AGROVOC _95760
650		7	_aNitrification _2AGROVOC _915865
650		7	_aNitrous oxide _2AGROVOC _94669
700	1		_97491 _aRobertson, G. P.
773	0		_gv. 11, no. 10, p. 1712-1719 _dUnited Kingdom : Wiley, 2005. _x1365-2486 _tGlobal Change Biology
942			_cJA _n0 _2ddc