DOI: 10.1007/s10533-016-0197-5
Scopus记录号: 2-s2.0-84960451159
论文题名: An integrated spectroscopic and wet chemical approach to investigate grass litter decomposition chemistry
作者: McKee G.A. ; Soong J.L. ; Caldéron F. ; Borch T. ; Cotrufo M.F.
刊名: Biogeochemistry
ISSN: 0168-2563
EISSN: 1573-515X
出版年: 2016
卷: 128, 期: 2018-01-02 起始页码: 107
结束页码: 123
语种: 英语
英文关键词: Big bluestem
; Cellulose
; FTIR
; Grass
; Hemicellulose
; Lignin
; Litter decomposition
; NMR
Scopus关键词: biogeochemistry
; cellulose
; chemical analysis
; decomposition
; grass
; integrated approach
; lignin
; litter
; microbial activity
; phytochemistry
; soil biota
; soil organic matter
; spectroscopy
; Andropogon gerardii
英文摘要: The chemical transformations that occur during litter decomposition are key processes for soil organic matter formation and terrestrial biogeochemistry; yet we still lack complete understanding of these chemical processes. Thus, we monitored the chemical composition of Andropogon gerardii (big bluestem grass) litter residue over a 36 month decomposition experiment in a prairie ecosystem using: traditional wet chemical fractionation based upon digestibility, solid state 13C nuclear magnetic resonance (NMR) spectroscopy and Fourier transform infrared (FTIR) spectroscopy. The goals of this study were to (1) determine the chemical changes occurring during A. gerardii litter decomposition, and (2) compare the information obtained from each method to assess agreement. Overall, we observed a 97 % mass loss of the original litter, through a two-stage decomposition process. In the first stage, within 12 months, non-structural, cellulose and hemicellulose fractions not encrusted in lignin were preferentially and rapidly lost, while the acid unhydrolyzable residue (AUR) and microbial components increased. During the second stage, 12–36 months, all wet chemical fraction masses decreased equivalently and slowly with time, and the AUR and the lignin-encrusted cellulose fractions decomposition rates were comparable to each other. Method comparisons revealed that wet chemical fractionation did not accurately follow the initial litter structures, particularly lignin, likely because of chemical transformations and accumulation of microbial biomass. FTIR and NMR were able to determine bulk structural characteristics, and aid in elucidating chemical transformations but lacked the ability to measure absolute quantities of structural groups. As a result, we warn from the sole use of wet chemical methods, and strongly encourage coupling them with spectroscopic methods. Our results overall support the traditional chemical model of selective preservation of lignin, but shows that this is limited to the early stages of decomposition, while lignin is not selectively preserved at subsequent stages. Our study also provides important evidence regarding the impact of chemically different litter structures on decomposition rates and pathways. © 2016, Springer International Publishing Switzerland. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/83402
Appears in Collections: 气候减缓与适应 气候变化事实与影响
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作者单位: Department of Soil and Crop Sciences, Colorado State University, Fort Collins, CO, United States; Natural Resource Ecology Laboratory, Colorado State University, Fort Collins, CO, United States; Agricultural Research Service, United States Department of Agriculture, Akron, CO, United States; Department of Chemistry, Colorado State University, Fort Collins, CO, United States; Department of Biology, University of Antwerp, Wilrijk, Belgium
Recommended Citation:
McKee G.A.,Soong J.L.,Caldéron F.,et al. An integrated spectroscopic and wet chemical approach to investigate grass litter decomposition chemistry[J]. Biogeochemistry,2016-01-01,128(2018-01-02)