ISSN:
1432-0789
Keywords:
Key words Polyacrylamide
;
Nitrogen fertilizer
;
Dicyandiamide
;
Polymerized urea
;
Polymer-encased urea
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Geosciences
,
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Abstract High molecular weight, anionic polyacrylamide (PAM) is currently being used as an irrigation water additive to significantly reduce soil erosion associated with furrow irrigation. PAM contains amide-N, and PAM application to soils has been correlated with increased activity of soil enzymes, such as urease and amidase, involved in N cycling. Therefore we investigated potential impacts of PAM treatment on the rate at which fertilizer N is transformed into NH4 + and NO3 – in soil. PAM-treated and untreated soil microcosms were amended with a variety of fertilizers, ranging from common rapid-release forms, such as ammonium sulfate [(NH4)2SO4] and urea, to a variety of slow-release formulations, including polymerized urea and polymer-encapsulated urea. Ammonium sulfate was also tested together with the nitrification inhibitor dicyandiamide (DCD). The fertilizers were applied at a concentration of 1.0 mg g–1, which is comparable to 100 lb acre–l, or 112 kg ha–1. Potassium chloride-extractable NH4 +-N and NO3 –-N were quantified periodically during 2–4 week incubations. PAM treatment had no significant effect on NH4 + release rates for any of the fertilizers tested and did not alter the efficacy of DCD as a nitrification inhibitor. However, the nitrification rate of urea and encapsulated urea-derived NH4 +-N was slightly accelerated in the PAM-treated soil.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s003740050652
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