The bottleneck in the turnover of soil organic matter (SOM) is the conversion of large molecular compounds into smaller compounds that can be transported through a cell membrane of a microbe for processing. Once inside the cell, organic compounds can be converted into biomass or be respired. The microbial depolymerization...
Soils have a critical role in global carbon (C) cycling, containing one of the largest fast-cycling carbon stocks on earth. Robust representation of soil organic matter dynamics in Earth System Models is critical for future climate prediction. Current C cycling models assume that all C cycling in non-hydric (i.e. ‘upland’)...
Soils and sediments worldwide contain appreciable amounts of thermally altered organic matter (chars) of both natural and industrial origin. Additions of chars into soils are discussed as a strategy to mitigate climate change. Chars contain electroactive quinoid functional groups and polycondensed aromatic sheets that were recently shown to be of...
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plant biomass-derived char black carbon (biochar) 3
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Laura Klüpfel†, MarcoKeiluweit§,‡, Markus
Soils and sediments worldwide contain appreciable amounts of thermally altered organic matter (chars) of both natural and industrial origin. Additions of chars into soils are discussed as a strategy to mitigate climate change. Chars contain electroactive quinoid functional groups and polycondensed aromatic sheets that were recently shown to be of...
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†, MarcoKeiluweit§,‡, Markus Kleber§,¶ , and Michael Sander†,* 5
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† Department of Environmental
Multiple lines of existing evidence suggest that climate change enhances root exudation of organic compounds into soils. Recent experimental studies show that increased exudate inputs may cause a net loss of soil carbon. This stimulation of microbial carbon mineralization ('priming') is commonly rationalized by the assumption that exudates provide a...
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Exudates 1
- Supporting Information – 2
Marco Keiluweit1,2*, Jeremy J. Bougoure2,3, Peter S. Nico4
Multiple lines of existing evidence suggest that climate change enhances root exudation of organic compounds into soils. Recent experimental studies show that increased exudate inputs may cause a net loss of soil carbon. This stimulation of microbial carbon mineralization ('priming') is commonly rationalized by the assumption that exudates provide a...
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root exudates
Mineral protection of soil carbon counteracted by root exudates
Keiluweit, M
Litter decomposition is a keystone ecosystem process impacting nutrient cycling and productivity, soil properties, and the terrestrial carbon (C) balance, but the factors regulating decomposition rate are still poorly understood. Traditional models assume that the rate is controlled by litter quality, relying on parameters such as lignin content as predictors....
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pnasSI201508945 1..5
Supporting Information
Keiluweit et al
Litter decomposition is a keystone ecosystem process impacting nutrient cycling and productivity, soil properties, and the terrestrial carbon (C) balance, but the factors regulating decomposition rate are still poorly understood. Traditional models assume that the rate is controlled by litter quality, relying on parameters such as lignin content as predictors....
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manganese redox cycling
Long-term litter decomposition controlled by manganese redox cycling
Keiluweit, M
The aromatic carbon structure is a defining property of chars and is often expressed with the help of two
concepts: (i) aromaticity and (ii) degree of aromatic condensation. The varying extent of these two features
is assumed to largely determine the relatively high persistence of charred material in the environment...
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Keiluweit et
S2
al. (2010). Increase in absorbance of aromatic C=C (285 eV) relative to oxygenated
The aromatic carbon structure is a defining property of chars and is often expressed with the help of two
concepts: (i) aromaticity and (ii) degree of aromatic condensation. The varying extent of these two features
is assumed to largely determine the relatively high persistence of charred material in the environment...
Full Text:
, MarcoKeiluweit c, Markus Kleber c,d,
Caroline A. Masiello e, Anna V. McBeath f, Peter S. Nico g, Lacey