Back to Search
Start Over
Modelling simultaneous release, diffusion and nitrification of ammonium in the soil surrounding a granule or nest containing ammonium fertilizer.
- Source :
-
European Journal of Soil Science . Jun98, Vol. 49 Issue 2, p351-364. 14p. - Publication Year :
- 1998
-
Abstract
- A model of nitrogen release from ammoniacal fertilizers into soil (e.g. from a controlled release nitrogen (CRN) source) and subsequent nitrification has been developed to assess possibilities for reducing losses of N and environment pollution. Emphasis was placed on the effects of changes in ammonium concentration and pH on nitrification rates, and the interactions of these effects with the rate of release of N from fertilizers. The model considers ammonium release and transport from a spherical source, such as a coated granule of CRN or a nest containing either granules of CRN or an easily dissolved fertilizer (EDF). It is shown that the appearance of nitrate in the soil decreases as the size of the N source increases. This is due to both a decrease in the rate of nitrification, caused by accumulation of ammonium near the source, and a slower relative release (i.e. smaller ratio of N released per unit time to the total mass initially in the source, which is inversely proportional to the radius of a granule or nest). Placement of many CRN granules in a nest is shown to be an effective way to reduce nitrification, particularly in soils having low microbial activities. The less the mobility of ammonium in the soil, the slower will be the nitrification because ammonium accumulates close to the source. A CRN nest leads to more effective reduction of nitrification than an EDF nest and N in it is released more slowly into the soil. [ABSTRACT FROM AUTHOR]
- Subjects :
- *AMMONIUM in soils
*FERTILIZERS
*NITRIFICATION
Subjects
Details
- Language :
- English
- ISSN :
- 13510754
- Volume :
- 49
- Issue :
- 2
- Database :
- Academic Search Index
- Journal :
- European Journal of Soil Science
- Publication Type :
- Academic Journal
- Accession number :
- 5279042
- Full Text :
- https://doi.org/10.1046/j.1365-2389.1998.00158.x