Characterization of Fresh and Decomposed Dissolved Organic Matter Using Excitation-Emission Matrix Fluorescence Spectroscopy and Multiway Analysis
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- 作者：James F. Hunt ; Tsutomu Ohno
- 刊名：Journal of Agricultural and Food Chemistry
- 出版年：2007
- 出版时间：March 21, 2007
- 年：2007
- 卷：55
- 期：6
- 页码：2121 - 2128
- 全文大小：375K
- 年卷期：v.55,no.6(March 21, 2007)
- ISSN：1520-5118
文摘
Fresh and decomposed dissolved organic matter (DOM) derived from 13 plant biomass and animalmanure sources was characterized using multidimensional fluorescence spectroscopy with parallelfactor analysis (PARAFAC), high-performance size-exclusion chromatography, and UV-vis spectroscopy. The PARAFAC analysis modeled seven fluorescence components: tryptophan-like, tyrosine-like, and five humic substance-like components. For most of the plant-derived DOM solutions,decomposition significantly affected the concentration of three humic substance-like-associatedcomponents, increasing two and decreasing one. The effect of decomposition upon DOM derivedfrom animal manures was dependent on the manure source. For a majority of the DOM extracts, theratio of fluorescence intensity to absorptivity at 254 nm increased following decomposition, indicatingthat fluorescing DOM compounds were generally more resistant to biodegradation than nonfluorescingUV-absorbing compounds. Molar absorptivity, humification index (HIX), and apparent molecular weight(MWAP) increased by 38.0, 38.8, and 370%, respectively, following decomposition. Spearmancorrelation analysis showed a strong positive relationship between the humic substance-likecomponents and the DOM MWAP, absorptivity, and HIX. The results of this study support the use ofmultidimensional fluorescence spectroscopy with PARAFAC as a method to monitor the decompositionof carbon-rich soil amendments such as crop residues, green manures, and animal manures.