Characterization of Sequentially Extracted Soil Organic Matter by Electrospray Ionization and Atmospheric Pressure Photoionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

Wang，Yinghui1,2; Liu，Yina3,4; Chu，Rosalie K.4; Bowden，Richard D.5; Lajtha，Kate6; Simpson，Myrna J.7; Wang，Junjian1

2022

10.1021/acsearthspacechem.2c00180

ACS Earth and Space Chemistry   Impact Factor & Quartile

2472-3452

2472-3452

Soil organic matter (SOM) is a complex mixture of small molecules and biopolymers that are active in various biogeochemical processes. However, the chemical diversity of biopolymer-derived SOM remains poorly explored. Identifying this diversity is important because global environmental changes may well alter SOM chemistry, as field experiments are beginning to show. Here, organic solvent-extractable (DcMe-SOM), base-hydrolyzable (KOHHy-SOM), and CuO-oxidizable (CuOOx-SOM) SOM fractions from a forest with a long-term nitrogen addition experiment were sequentially extracted and characterized by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) coupled with negative-ion electrospray ionization (ESI) or atmospheric pressure photoionization (APPI). From DcMe-SOM to CuOOx-SOM, the total number of assigned formulas, average O/C ratio, aromaticity, and unsaturation degree of SOM continuously increased, while the average m/z and H/C ratio decreased. Moreover, the dominant chemical category shifted from lipid-like components to phytochemical- and protein-like components. Complementary to ESI, APPI effectively facilitated detection of additional compounds with low polarity. With long-term nitrogen addition, the average m/z, unsaturation degree, aromaticity, and oxidation state of SOM increased, and more aromatic nitrogen-containing formulas were detected in CuOOx-SOM. Our study demonstrates that chronic nitrogen deposition in forests alters both the small molecules and biopolymers of SOM fundamentally.

Fourier transform ion cyclotron resonance mass spectrometry ionization selectivity nitrogen deposition sequential extraction soil organic carbon

SCI

English

First ; Corresponding

National Natural Science Foundation of China (NSFC)["42192513","42122054"]

Chemistry ; Geochemistry & Geophysics

Chemistry, Multidisciplinary ; Geochemistry & Geophysics

WOS:000856030300001

AMER CHEMICAL SOC

2-s2.0-85136666575

Scopus

1.State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control,School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,518055,China
2.State Key Laboratory of Water Resources and Hydropower Engineering Science,Wuhan University,Wuhan,430072,China
3.Department of Oceanography,Texas A&M University,College Station,77843,United States
4.Environmental Molecular Sciences Laboratory,Pacific Northwest National Laboratory,Richland,99354,United States
5.Department of Environmental Science and Sustainability,Allegheny College,Meadville,16335,United States
6.College of Crop and Soil Science,Oregon State University,Corvallis,97331,United States
7.Environmental NMR Centre,Department of Physical and Environmental Sciences,University of Toronto Scarborough,Toronto,M1C 1A4,Canada

Wang，Yinghui,Liu，Yina,Chu，Rosalie K.,et al. Characterization of Sequentially Extracted Soil Organic Matter by Electrospray Ionization and Atmospheric Pressure Photoionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry[J]. ACS Earth and Space Chemistry,2022,6(9).

Wang，Yinghui.,Liu，Yina.,Chu，Rosalie K..,Bowden，Richard D..,Lajtha，Kate.,...&Wang，Junjian.(2022).Characterization of Sequentially Extracted Soil Organic Matter by Electrospray Ionization and Atmospheric Pressure Photoionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry.ACS Earth and Space Chemistry,6(9).

Wang，Yinghui,et al."Characterization of Sequentially Extracted Soil Organic Matter by Electrospray Ionization and Atmospheric Pressure Photoionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry".ACS Earth and Space Chemistry 6.9(2022).