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On‐Farm Assessment of the Amount and Timing of Nitrogen Fertilizer on Ammonia Volatilization
Author(s) -
Ma B. L.,
Wu T. Y.,
Tremblay N.,
Deen W.,
McLaughlin N. B.,
Morrison M. J.,
Stewart G.
Publication year - 2010
Publication title -
agronomy journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.752
H-Index - 131
eISSN - 1435-0645
pISSN - 0002-1962
DOI - 10.2134/agronj2009.0021
Subject(s) - volatilisation , ammonia volatilization from urea , fertilizer , nitrogen , ammonia , chemistry , agronomy , environmental science , human fertilization , flux (metallurgy) , environmental chemistry , biology , organic chemistry
Ammonia (NH 3 ) volatilization is one of the main pathways through which applied N enters the environment undesirably. A seven site‐year on‐farm field experiment was performed for 3 yr at Ottawa, ON, and 2 yr at Guelph, ON, and Saint‐Valentin, QC, Canada. Our objectives were to (i) quantify the flux and the amount of NH 3 volatilization as affected by the rate and time of N fertilizer; (ii) assess the impact of rainfall and soil temperatures on NH 3 volatilization; and (iii) determine the threshold level of N fertilizer at which large NH 3 volatilization losses occur. Using the static chamber method, NH 3 volatilization was monitored after preplant or sidedress N application. Rate of NH 3 volatilization peaked at 3 to 7 d and then dropped sharply within next 7 d before leveling off in the following weeks. The amount of NH 3 volatilization increased with increasing N levels applied preplant or sidedress at all site‐years. Peak NH 3 volatilization ranged from 40 to 8000 g N ha −1 d −1 after preplant fertilization and from about 100 to 2100 g N ha −1 d −1 after sidedress, resulting in NH 3 losses of 0.1 to 47 kg N ha −1 and 0.6 to 20 kg N ha −1 , respectively, equivalent to 0.1 to 38% and 0.3 to 13% of fertilizer‐induced emission (FIE) within 28 d after preplant or sidedress N fertilization. Our data clearly indicate that sidedress applications enable reduction in N fertilizer for economic crop yields, and may reduce losses simply due to lower total N rates.