About Us | Help Videos | Contact Us | Subscriptions



This article in JEQ

  1. Vol. 17 No. 4, p. 719-723
    Received: Aug 18, 1987

    * Corresponding author(s):
Request Permissions


Desorption of Atrazine and Cyanazine from Soil

  1. S. A. Clay *,
  2. R. R. Allmaras,
  3. W. C. Koskinen and
  4. D. L. Wyse
  1. USDA-Agricultural Research Service, 439 Borlaug Hall, 1991 Upper Buford Circle, St. Paul, MN 55108;
    Dep. of Agronomy and Plant Genetics, Univ. of Minnesota, St. Paul, MN 55108.



Removal of soluble soil organic carbon (SSOC) during herbicide desorption studies using the batch equilibration method may affect the herbicide-soil-solution equilibrium particularly if herbicide-SSOC complexes can form. Desorption characteristics of atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) and cyanazine (2-{[4-chloro-6-(ethylamino)-s-triazine-2-yl]amino}-2-methylpropionitrile] were determined in a Ves clay loam (Aquic Hapludolls). For adsorption, the soil was equilibrated with 0.01 M CaCl2 solutions containing atrazine or cyanazine. Desorption with 0.01 M CaCl2 each day for 5 d resulted in hysteresis when compared to the adsorption isotherm. Replacement of the equilibration solution with soil extract for 5 d, while maintaining a higher SSOC content in the desorption equilibration solution than did the CaCl2 solution, did not change desorption isotherm equations. The SSOC-herbicide complexes were not detected in any of the adsorption and desorption equilibration solutions by ultrafiltration (membranes with molecular mass cut offs of 10 000 and 500 daltons), HPLC, or TLC techniques. Either s-triazine-SSOC complexes were not formed in sufficient quantities or they were not stable enough to affect desorption of the herbicide during batch equilibration.

Contribution of the Soil and Water Manage. Res. Unit, USDA-ARS, St. Paul, MN, and the Minnesota Agric. Exp. Stn. Journal Ser. Paper no. 15 557.

  Please view the pdf by using the Full Text (PDF) link under 'View' to the left.

Copyright © .