ISSN:
1573-0867
Schlagwort(e):
exchangeable NH 4 +
;
nonexchangeable NH 4 +
;
15N tracer technique
;
NH 4 + fixation
;
vermiculite
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
Notizen:
Abstract The release of non-exchangeable (fixed) NH 4 + and the importance of exchangeable NH 4 + at transplanting (initial exchangeable NH 4 + ) for rice (Oryza sativa L.) growth was studied in representative lowland rice soils of the Philippines. The experiments showed that initial exchangeable ammonium behaved like fertilizer N and thus may serve as a valuable guideline for nitrogen fertilizer application rates when calculated on a hectare basis. By using the15N tracer technique it was found that nonexchangeable ammonium in soil may contribute to the nitrogen supplying capacity of lowland rice soils. Fixation and release of NH 4 + seem to be more dependent on the form of clay minerals than on clay content. In soils rich in vermiculite non-exchangeable ammonium should be considered together with other available N sources such as exchangeable ammonium for N fertilizer recommendations for lowland rice.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF01048698
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