AUTOMATED GAS SAMPLING SYSTEM FOR LABORATORY ANALYSIS OF CH₄ AND N₂O

Authors

Spencer L. Arnold, University of Nebraska-LincolnFollow
Timothy B. Parkin, USDA-ARS-NSTL
John W. Doran, University of Nebraska-LincolnFollow
Bahman Eghball, United States Department of AgricultureFollow
Arvin R. Mosier, USDA-ARS-NPA-SP&NR

Date of this Version

2001

Comments

Published in COMMUN. SOIL SCI. PLANT ANAL., 32(17&18), 2795–2807 (2001).

Abstract

Analyzing the flux of CH₄ and N₂O from soil is labor intensive when conventional hand injection techniques are utilized in gas chromatography. An automated gas sampling system was designed and assembled from a prototype developed at the National Soil Tilth Laboratory in Ames, IA. The sampler was evaluated for accuracy and precision when attached to a Varian 3700 gas chromatograph configured with flame ionization and electron capture detectors. The automated gas sampling system is easy to operate and provides acceptable results (standards ranging from 1.0–5.0 ppmv CH₄ and 0.342–2.0 ppmv N₂O had coefficients of variation ranging from 1.7–5.6%) while providing an economical approach for analyzing large numbers of gas samples with minimal labor and equipment cost.