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 Bauder, J. W. Articles by Schneider, R. P. Search for Related Content PubMed Articles by Bauder, J. W. Articles by Schneider, R. P. Agricola Articles by Bauder, J. W. Articles by Schneider, R. P.

Nitrate-Nitrogen Leaching Following Urea Fertilization and Irrigation¹

ABSTRACT

Wheat (Triticum aestivum) was grown in undisturbed columns of Gardena silt loam, a coarse-silty, mixed Pachic Udic Haploboroll, to evaluate NO₃^--N leaching from urea under irrigation. Optimum and excessive irrigation rates and 135 kg N/ha (as urea in single application vs. three increments applied during the growing period) were compared in factorial combination. Chloride was added to all columns for comparison with NO₃^--N. Leachate samples were collected throughout the study and analyzed for NO₃^--N, NH₄⁺-N and Cl^-. Columns were dismantled at crop maturity and sampled for residual NO₃^--N. Total N was determined in wheat at maturity.

Leaching fractions (LF) differed significantly between optimum and excessive irrigation but were not affected by applied urea. Cl^- moved with the wetting front. Leaching patterns for NO₃^--N and Cl^- were similar, but a slight lag in NO₃^--N was observed. Concentration of NO₃^--N in drainage water from all columns was initially similar (30 ppm NO₃^--N), but then decreased as leaching volume changed. Maximum NO₃^--N leaching occurred with split urea and excess irrigation. Minimum leaching occurred with optimum irrigation and split urea. Total NO₃^--N leachate load was directly correlated with leachate volume. Soil solution concentrations at crop maturity were as much as 170 µg NO₃^--N/ml. Residual NO₃^--N varied among treatments and revealed as many as three peaks in NO₃^--N concentration in the profile, indicating that N leaching occurred following each urea application. The results indicate marked NO₃^--N movement from urea under excessive irrigation.

¹ Contribution from Dept. of Soils, North Dakota Agric. Exp. Stn., North Dakota State Univ., Fargo, ND 58105. Published with the approval of the Director, North Dakota Agric. Exp. Stn. as Journal Article No. 941.

² Assistant Professors, Dept. of Soils, North Dakota State Univ., Fargo, ND 58105. Senior author is now Assistant Professor, Dept. of Soil Science, Univ. of Minn., St. Paul, Minn. 55108.

Received for publication February 6, 1978. Accepted for publication October 23, 1978.