|DU, CHANGWEN - Chinese Academy Of Sciences|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 4/20/2009
Publication Date: 7/6/2009
Citation: He, Z., Honeycutt, C.W., Du, C. 2009. FT-IR quantification of aliphatic and carboxyl groups in soil humic fractions. [abstracts]. p. 144.
Technical Abstract: Aliphatic and carboxyl groups are two important components in soil humic fractions. Absorbance bands in the ranges of 3020-2800 cm-1 (band A) and 1720-1600 cm-1 (band B) in Fourier Transform Infrared (FT-IR) spectra have been attributed to aliphatic and carboxyl groups, respectively. We prepared mobile humic acid (MHA) and recalcitrant calcium humate (CaHA) from 10 soils collected from six states in the USA. FT-IR spectra of these humic fractions were collected. Absorption bands of the original and ash-corrected FT-IR spectra were quantified using absorption height and area. High correlation observed between the original and ash-corrected spectra indicated that ash correction is not necessary. The correlation between height and area exceeded 0.946, indicating that both band height and area measurements are acceptable for semi-quantification of FT-IR spectra. This work demonstrated that FT-IR measurement may provide a simple and fast method for semi-quantifying these two functional groups of humic acid fractions.