My Account: Log In | Join | Renew
Search
Author
Title
Vol.
Issue
Year
1st Page

Abstract

 

This article in JEQ

  1. Vol. 31 No. 2, p. 619-627
     
    Received: Feb 9, 2001
    Published: Mar, 2002


    * Corresponding author(s): john.letey@ucr.edu
 View
 Download
 Alerts
 Permissions
 Share

doi:10.2134/jeq2002.6190

Molecular Weight of Dissolved Organic Matter–Napropamide Complex Transported through Soil Columns

  1. C. F. Williamsa,
  2. J. Letey *b and
  3. W. J. Farmerb
  1. a Dep. of Plants, Soils, and Biometeorology, Utah State Univ., Logan, UT 84322-4820
    b Dep. of Environmental Science, Univ. of California, Riverside, CA 92521-0424

Abstract

Soil-derived dissolved organic matter (DOM) has been shown to form stable complexes with the herbicide napropamide [2-(α-naphthoxy-N,N-diethylpropionamide] capable of enhancing the transport of napropamide through soil columns. Two soils, one containing sewage sludge–derived organic matter (SS) and the other having only natural organic matter (NoSS) were treated with napropamide and allowed to dry to promote complex formation. Soil columns were prepared by packing a 10-cm layer of untreated, dry, sieved soil followed by an overlying 5-cm layer of napropamide-treated soil. Columns were irrigated and the effluent collected and placed in dialysis chambers. After equilibration napropamide concentrations were determined on both sides of the membrane and complex and quantified based on the amount of napropamide unable to cross the membrane. It was found that for the SS soil 7% and for the NoSS 2.4% of the applied napropamide underwent facilitated transport. In addition, most of the complex transported through the columns had a molecular weight between 500 and 1000 Daltons (Da). The solutions from the SS soil were also found to have formed at least two distinct complexes that were resolved after passing through the untreated soil layer. The results obtained were in agreement with other published results and the techniques used offer a way to separate and concentrate DOM complexes from column effluents for further characterization.

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

Copyright © 2002. American Society of Agronomy, Crop Science Society of America, Soil Science SocietyPublished in J. Environ. Qual.31:619–627.