|
|
||||||||
Dep. of Plant, Soil and Insect Science, Univ. of Wyoming, Laramie, WY 82071-3354
Center for Agricultural Molecular Biology, Rutgers Univ., Cook College, New Brunswick, NJ 08903-0231
Dep. of Natural Resources and Environmental Sciences, Univ. of Illinois, Urbana, IL 61801
*Corresponding author (gfv{at}uwyo.edu).
ABSTRACT
Low molecular weight organic acids (LMWOA) from root exudates, decomposing organic matter, and other sources are important lignads involved in solution complexation reactions as well as ligand exchange reactions at mineral surfaces. The purpose of this study was to (i) develop an ion chromatography method that could be used to determine LMWOA in soil solutions from Spodosols, (ii) assess methods for preserving LMWOA in soil solutions, and (iii) evaluate LMWOA concentrations in forest floor solutions during a growing season. Solutions were collected weekly from zero-tension lysimeters installed within the forest floor (forest floor leachate collectors). Limits of quantitation for acetic, formic, malonic, oxalic, phthalic, and citric acids were 0.35, 0.14, 0.43, 0.41, 0.07, and 0.04 µM, respectively, which in some cases are an order of magnitude lower than reported in previous studies. Freezing soil solutions after filtering resulted in the best recoveries (between 90 and 100% for all LMWOA); other methods of preservation, such as filtering alone and filtering and storing at 4°C, resulted in lower recoveries. The average concentrations of LMWOA in the forest floor solutions were 10 µM acetic acid, 0.7 µM formic acid, and 3.3 µM oxalic acid. Dissolved organic C from the forest floor contained a maximum concentration of 2.0% acetic acid, 0.01% formic acid, and 0.15% oxalic acid. There were no apparent temporal patterns in LMWOA concentrations, except for a decrease in LMWOA concentrations from late September to a minimum in October.
Received for publication April 17, 1995.
This article has been cited by other articles:
![]() |
R. J. Schaetzl, B. D. Knapp, and S. A. Isard Modeling Soil Temperatures and the Mesic-Frigid Boundary in the Central Great Lakes Region, 1951-2000 Soil Sci. Soc. Am. J., October 27, 2005; 69(6): 2033 - 2040. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| The SCI Journals | Agronomy Journal | Crop Science | |||
| Journal of Natural Resources and Life Sciences Education |
Vadose Zone Journal | ||||
| Journal of Plant Registrations | Journal of Environmental Quality |
The Plant Genome | |||