Journal article

Publication year: 1981

Pages: 226-232

Journal: Soil Science

Volume number: 131

Issue number: 4

ISSN: 0038-075X

eISSN: 1538-9243

DOI Link: https://doi.org/10.1097/00010694-198104000-00006

Publisher: Lippincott, Williams & Wilkins

Abstract: 
The release of fixed (nonexchangeable) NH4+ by clay minerals under field conditions was studied on 2 representative arable sites, one on loess and the other on alluvial soil. The nonexchangeable NH4+ content of soil from 3 depths was determined at 5 dates during the growing season in fields carrying winter barley (loess) or spring oats (alluvial soil). There were significant changes in the content of nonexchangeable NH4+ during the growing period. Early in crop growth particularly, the upper soil layers (0-60 cm) were depleted of nonexchangeable NH4+; later, nonexchangeable NH4+ declined at the depth of 60-90 cm. The nonexchangeable NH4+ content of alluvial soil recovered to approximately its original level at the end of the growing season. There was a substantial net loss of nonexchangeable NH4+ from the loess soil of about 40 ppm, equivalent to 500 kg N/ha assuming a soil depth of 90 cm. Soil samples labeled with nonexchangeable 15NH4+ and placed back into the field under sugar beet at the depths from which the samples had been taken released, between May and Oct., significant quantities of labeled nonexchangeable NH4+, which, on the basis of a soil depth of 75 cm, were equivalent to about 350 kg N/ha in the loess and 150 kg N/ha in the alluvial soil. In these soil types, which are representative of many arable soils in central Europe, the so-called fixed NH4+ is probably involved in the general soil N cycle.

Harvard Citation style: MENGEL, K. and SCHERER, H. (1981) RELEASE OF NON-EXCHANGEABLE (FIXED) SOIL AMMONIUM UNDER FIELD CONDITIONS DURING THE GROWING-SEASON, Soil Science, 131(4), pp. 226-232. https://doi.org/10.1097/00010694-198104000-00006

APA Citation style: MENGEL, K., & SCHERER, H. (1981). RELEASE OF NON-EXCHANGEABLE (FIXED) SOIL AMMONIUM UNDER FIELD CONDITIONS DURING THE GROWING-SEASON. Soil Science. 131(4), 226-232. https://doi.org/10.1097/00010694-198104000-00006