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

This Article Figures Only Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (3) Citing Articles via Google Scholar Google Scholar Articles by Butters, G.L. Articles by Ruan, H. Search for Related Content PubMed Articles by Butters, G.L. Articles by Ruan, H. GeoRef GeoRef Citation Agricola Articles by Butters, G.L. Articles by Ruan, H.

DIVISION S-6-SOIL & WATER MANAGEMENT & CONSERVATION

Bromide and Atrazine Leaching in Furrow- and Sprinkler-Irrigated Corn

^a Dep. of Soil and Crop Sciences, Colorado State Univ., Ft. Collins, CO 80523 USA
^b Central Great Plains Research Unit, USDA-ARS, Akron, CO 80720 USA
^c Great Plains Systems Research Unit, USDA-ARS, Ft. Collins, CO 80522 USA

gbutters{at}agsci.colostate.edu

Irrigation method is an important consideration in the management of nutrients and pesticides. A 2-yr study was undertaken to evaluate Br^- and atrazine [6-chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine] leaching following uniform spray application in a corn (Zea mays L.) field under three irrigation treatments: (i) furrow irrigation with water placement in every furrow (EF), (ii) furrow irrigation with water placement (at twice the rate) in alternate furrows (AF), and (iii) sprinkler irrigation (SP). The soil, a Fort Collins clay loam (fine-loamy, mixed, superactive, mesic Aridic Haplustalf), was ridged and furrowed for all irrigation treatments. In both years of the study, Br^- movement under all three irrigation treatments was dominated by lateral flow into the ridge and/or dry furrow positions. The deepest Br^- leaching was found in the SP treatment, but with irrigation scheduled at 100% of evapotranspiration (ET) in no case in either year did Br^- mass below the root zone (1.2 m) exceed 3% of applied mass. Comparing the furrow irrigation treatments, applying water at twice the rate to alternative furrows neither increased nor decreased the plot averaged downward movement of Br^-. Atrazine movement was largely unaffected by the type and placement of irrigation, though in each treatment the downward leaching of atrazine was much greater than expected, suggesting nonequilibrium conditions and/or movement with a mobile reactive phase. A modified version of the unsaturated flow and transport code CHAIN-2D, which included two-dimensional root water and solute uptake with partitioning of the soil water into mobile and immobile regions, accurately simulated the Br^- concentration profiles. The model will be useful in evaluating management alternatives for the placement of water and chemicals that minimize losses below the root zone.

Abbreviations: AF, alternate-furrow irrigation treatment • EF, every-furro irrigation treatment • ET, evapotranspiration • LEPA, Low Energy, Precision Application • SP, sprinkler irrigation treatment

This article has been cited by other articles:

				G. Alavi, J. Dusek, T. Vogel, R. E. Green, and C. Ray Evaluation of Dual-Permeability Models for Chemical Leaching Assessment to Assist Pesticide Regulation in Hawaii Vadose Zone J., October 8, 2007; 6(4): 735 - 745. [Abstract] [Full Text] [PDF]

				J. Fortin, E. Gagnon-Bertrand, L. Vezina, and M. Rompre Preferential Bromide and Pesticide Movement to Tile Drains under Different Cropping Practices J. Environ. Qual., November 1, 2002; 31(6): 1940 - 1952. [Abstract] [Full Text] [PDF]