HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by McDowell, L. L. Articles by Smith, G. E. Search for Related Content PubMed Articles by McDowell, L. L. Articles by Smith, G. E. Agricola Articles by McDowell, L. L. Articles by Smith, G. E.

The Retention and Reactions of Anhydrous Ammonia on Different Soil Types¹

ABSTRACT

Soil texture had a pronounced effect on ammonia movement and retention. The greatest movement of ammonia occurred in the sand and silt loam soils; and the least movement in the clay. The loss of ammonia from the airdry, acid sandy soil at a 6-inch depth of application was 44 times the loss from the calcareous clay soil receiving ammonia at comparable moisture and depth. The retentive capacity of a soil for ammonia increased greatly as the texture became heavier. The loss of ammonia from the air-dry, calcareous clay soil was negligible even at the 3-inch depth of application. A considerable portion of the nitrogen applied as anhydrous ammonia was lost to the atmosphere or was fixed in some form making it non-extractable by the chemical analysis used. The amount of ammonia fixed increased with the greater clay content of the soil.

The presence of high concentrations of ammonia in a localized area resulted in the partial breakdown of the soil organic matter. As a result of nitrification and the subsequent increase in hydrogen-ion concentration this condition was no longer observed at the end of 4 weeks of incubation.

Ammonia losses were reduced considerably when the application was changed from 40-inch to 16-inch spacings and the rate applied per acre was maintained a constant.

¹ Contribution from the Missouri Agr. Exp. Sta., Journal Series No. 1693. Approved by the Director. Presented before Div. IV, Soil Science Society of America, Cincinnati, Ohio, Nov. 14, 1956.

² Assistant in Soils and Professor of Soils, respectively. This study was supported in part by a grant from the Phillips Petroleum Company, Bartlesville, Oklahoma. The Houston Black clay soil used in these experiments was supplied by Dr. R. M. Smith of Temple, Texas.

Received for publication December 6, 1956. Accepted for publication September 12, 1957.