Journalartikel

Jahr der Veröffentlichung: 1987

Seiten: 171-177

Zeitschrift: Biology and Fertility of Soils

Bandnummer: 4

Heftnummer: 4

ISSN: 0178-2762

eISSN: 1432-0789

DOI Link: https://doi.org/10.1007/BF00270937

Verlag: Springer

Abstract: 
The dynamics of basally applied 15N-labeled ammonium sulfate in inorganic and organic soil fractions of five wetland rice soils of the Philippines was studied in a greenhouse experiment. Soil and plant samples were collected and analyzed fro 15N at various growth stages. Exchangeable NH4+ depletion continued after 40 days after transplanting (DAT) and corresponded with increased nitrogen uptake by rice plants. Part of the applied fertilizer was fixed by 2:1 clay minerals, especially in Maligava silty clay loam, which contained beidellite as the dominant clay mineral. After the initial fixation, nonexchangeable 15N was released from 20 DAT in Maligaya silty clay loam, but fixation delayed fertilizer N uptake from the soil. Part of the applied N was immobilized into the organic fraction. In Guadalupe clay and Maligaya silty clay loam, immobilization increased with time while the three other soils showed significant release of fertilizer N from the organic fraction during crop growth. Most of the immobilized fertilizer N was recovered in the nondistillable acid-solbule (alpha-amino acid+hydrolyzable unknown-N) fraction at crop maturity. Between 61% and 66% of applied N was recovered from the plant in four soils while 52% of fertilizer N was recovered from the plant in Maligaya silty loam. Only 20%-30% of the total N uptake at maturity was deliver from fertilizer N. Nmin (mineral N) content of the soil before transplanting significantly correlated with N uptake. Twenty-two to 34% of applied N was unaccounted for possiblyd ue to denitrification and ammonia volatilization.

Harvard-Zitierstil: SCHNIER, H., DEDATTA, S. and MENGEL, K. (1987) DYNAMICS OF N-15-LABELED AMMONIUM-SULFATE IN VARIOUS INORGANIC AND ORGANIC SOIL FRACTIONS OF WETLAND RICE SOILS, Biology and Fertility of Soils, 4(4), pp. 171-177. https://doi.org/10.1007/BF00270937

APA-Zitierstil: SCHNIER, H., DEDATTA, S., & MENGEL, K. (1987). DYNAMICS OF N-15-LABELED AMMONIUM-SULFATE IN VARIOUS INORGANIC AND ORGANIC SOIL FRACTIONS OF WETLAND RICE SOILS. Biology and Fertility of Soils. 4(4), 171-177. https://doi.org/10.1007/BF00270937