Ammonia and nitrous oxide emissions as affected by nitrification and urease inhibitors

Marta Alfaro, Francisco Salazar, Sara Hube, Luis Ramírez, Ma. Soledad Mora
2018 Journal of soil science and plant nutrition  
Soil Nitrogen (N) gaseous losses have environmental and economic implications. Ammonia (NH 3 ) volatilization and nitrous oxide (N 2 O) emissions from a volcanic soil were concurrently quantified using intact lysimeters, after application of the equivalent to 100 kg N ha -1 with and without urease (NBPT) and nitrification (DCD) inhibitor: Urea, Urea+NBPT, Urea+DCD, Dairy slurry and Dairy slurry+DCD. A control treatment (-N) was also included. Treatments were distributed on a randomized block
more » ... randomized block design and evaluated during 28 days. Ammonia was analyzed for NH 4 by colorimetry, while N 2 O was estimated by gas chromatography. Total emissions were estimated by addition of daily fluxes, and results were analyzed by ANOVA. Ammonia was the main N loss, with 35 to 43% and 5% to 16% of the total N applied in Urea and Dairy slurry (P<0.01), respectively, with and without inhibitors (P>0.05). The use of DCD reduced N 2 O emissions by 44 and 8% in the same treatments, respectively (P<0.05). Results suggest that DCD has a potential as a mitigation option in grassland volcanic soils reducing N 2 O losses. The use of NBPT did not reduce NH 3 losses and N 2 O emissions when applied with urea. Concurrent N gasses losses from soil showed that indirect N 2 O losses following NH 3 volatilization might be more relevant in volcanic soils than direct N 2 O losses.
doi:10.4067/s0718-95162018005001501 fatcat:dnddgl5je5ekhc36ouywp5h5ae