@article {2942,
	title = {Soil Organic Carbon Development and Turnover in Natural and Disturbed Salt Marsh Environments},
	journal = {Geophysical Research Letters},
	volume = {48},
	year = {2021},
	month = {Apr-01-2023},
	abstract = {Salt marsh survival with sea-level rise (SLR) increasingly relies on soil organic carbon (SOC) accumulation and preservation. Using a novel combination of geochemical approaches, we characterized fine SOC (<=1 mm) supporting marsh elevation maintenance. Overlaying thermal reactivity, source (δ13C), and age (F14C) information demonstrates several processes contributing to soil development: marsh grass production, redeposition of eroded material, and microbial reworking. Redeposition of old carbon, likely from creekbanks, represented \~{}9\%{\textendash}17\% of shallow SOC (<=26 cm). Soils stored marsh grass-derived compounds with a range of reactivities that were reworked over centuries-to-millennia. Decomposition decreases SOC thermal reactivity throughout the soil column while the decades-long disturbance of ponding accelerated this shift in surface horizons. Empirically derived estimates of SOC turnover based on geochemical composition spanned a wide range (640{\textendash}9,951 years) and have the potential to inform predictions of marsh ecosystem evolution.},
	issn = {0094-8276},
	doi = {10.1029/2020GL090287},
	url = {https://onlinelibrary.wiley.com/doi/10.1029/2020GL090287},
	author = {Luk, Sheron Y. and Todd-Brown, Katherine and Eagle, Meagan and McNichol, Ann P. and Sanderman, Jonathan and Gosselin, Kelsey and Spivak, Amanda C.}
}
@article {2877,
	title = {Ramped thermal analysis for isolating biologically meaningful soil organic matter fractions with distinct residence times},
	journal = {SOIL},
	volume = {6},
	year = {2020},
	month = {Jan-01-2020},
	pages = {131 - 144},
	abstract = {In this work, we assess whether or not ramped thermal oxidation coupled with determination of the radiocarbon content of the evolved CO2 can be used to isolate distinct thermal fractions of soil organic matter (SOM) along with direct information on the turnover rate of each thermal fraction. Using a 30-year time series of soil samples from a well-characterized agronomic trial, we found that the incorporation of the bomb spike in atmospheric 14CO2 into thermal fractions of increasing resistance to thermal decomposition could be successfully modeled. With increasing temperature, which is proportional to activation energy, the mean residence time of the thermal fractions increased from 10 to 400 years. Importantly, the first four of five thermal fractions appeared to be a mixture of fast- and increasingly slower-cycling SOM. To further understand the composition of different thermal fractions, stepped pyrolysis{\textendash}gas chromatography{\textendash}mass spectrometry (Py-GC/MS) experiments were performed at five temperatures ranging from 330 to 735 oC. The Py-GC/MS data showed a reproducible shift in the chemistry of pyrolysis products across the temperature gradient trending from polysaccharides and lipids at low temperature to lignin- and microbe-derived compounds at middle temperatures to aromatic and unknown compounds at the highest temperatures. Integrating the 14C and Py-GC/MS data suggests the organic compounds, with the exception of aromatic moieties likely derived from wildfire, with centennial residence times are not more complex but may be protected from pyrolysis, and likely also from biological mineralization, by interactions with mineral surfaces.},
	doi = {10.5194/soil-6-131-2020},
	url = {https://soil.copernicus.org/articles/6/131/2020/},
	author = {Sanderman, Jonathan and Grandy, A. Stuart}
}
