Bioavailability and isotopic composition of CO2 released from incubated soil organic matter fractions

Mueller, Carsten W.; Gutsch, Martin; Kothieringer, Katja; Leifeld, Jens; Rethemeyer, Janet; Brüggemann, Nicolas; Kögel‐Knabner, Ingrid

doi:10.1016/j.soilbio.2013.11.006

Cited by 47 publications

(30 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…These findings are in agreement with the findings of Mueller et al. () and confirm that the more recently fixed OC was respired first during the incubation.…”

Section: Discussionsupporting

confidence: 93%

Temperature response of permafrost soil carbon is attenuated by mineral protection

Gentsch

Wild

Mikutta

et al. 2018

Global Change Biology

107

View full text Add to dashboard Cite

Climate change in Arctic ecosystems fosters permafrost thaw and makes massive amounts of ancient soil organic carbon (OC) available to microbial breakdown. However, fractions of the organic matter (OM) may be protected from rapid decomposition by their association with minerals. Little is known about the effects of mineral-organic associations (MOA) on the microbial accessibility of OM in permafrost soils and it is not clear which factors control its temperature sensitivity. In order to investigate if and how permafrost soil OC turnover is affected by mineral controls, the heavy fraction (HF) representing mostly MOA was obtained by density fractionation from 27 permafrost soil profiles of the Siberian Arctic. In parallel laboratory incubations, the unfractionated soils (bulk) and their HF were comparatively incubated for 175 days at 5 and 15°C. The HF was equivalent to 70 ± 9% of the bulk CO respiration as compared to a share of 63 ± 1% of bulk OC that was stored in the HF. Significant reduction of OC mineralization was found in all treatments with increasing OC content of the HF (HF-OC), clay-size minerals and Fe or Al oxyhydroxides. Temperature sensitivity (Q10) decreased with increasing soil depth from 2.4 to 1.4 in the bulk soil and from 2.9 to 1.5 in the HF. A concurrent increase in the metal-to-HF-OC ratios with soil depth suggests a stronger bonding of OM to minerals in the subsoil. There, the younger C signature in CO than that of the OC indicates a preferential decomposition of the more recent OM and the existence of a MOA fraction with limited access of OM to decomposers. These results indicate strong mineral controls on the decomposability of OM after permafrost thaw and on its temperature sensitivity. Thus, we here provide evidence that OM temperature sensitivity can be attenuated by MOA in permafrost soils.

show abstract

“…These findings are in agreement with the findings of Mueller et al. () and confirm that the more recently fixed OC was respired first during the incubation.…”

Section: Discussionsupporting

confidence: 93%

Temperature response of permafrost soil carbon is attenuated by mineral protection

Gentsch

Wild

Mikutta

et al. 2018

Global Change Biology

107

View full text Add to dashboard Cite

show abstract

“…Each size‐fraction was freeze‐dried and weighed. The POM in the <20 µm fraction was isolated by flotation in sodium polytungstate (SPT) solution with a density of 1.8 g/cm 3 (Mueller et al, ). This density was selected to obtain a “clean” POM fraction comprised solely of light OM particles, and MOM without contamination with light OM.…”

Section: Methodsmentioning

confidence: 99%

Soil organic carbon stability in forests: Distinct effects of tree species identity and traits

Angst

Mueller

Eissenstat

et al. 2019

Global Change Biology

Self Cite

109

View full text Add to dashboard Cite

Rising atmospheric CO2 concentrations have increased interest in the potential for forest ecosystems and soils to act as carbon (C) sinks. While soil organic C contents often vary with tree species identity, little is known about if, and how, tree species influence the stability of C in soil. Using a 40 year old common garden experiment with replicated plots of eleven temperate tree species, we investigated relationships between soil organic matter (SOM) stability in mineral soils and 17 ecological factors (including tree tissue chemistry, magnitude of organic matter inputs to the soil and their turnover, microbial community descriptors, and soil physicochemical properties). We measured five SOM stability indices, including heterotrophic respiration, C in aggregate occluded particulate organic matter (POM) and mineral associated SOM, and bulk SOM δ15N and ∆14C. The stability of SOM varied substantially among tree species, and this variability was independent of the amount of organic C in soils. Thus, when considering forest soils as C sinks, the stability of C stocks must be considered in addition to their size. Further, our results suggest tree species regulate soil C stability via the composition of their tissues, especially roots. Stability of SOM appeared to be greater (as indicated by higher δ15N and reduced respiration) beneath species with higher concentrations of nitrogen and lower amounts of acid insoluble compounds in their roots, while SOM stability appeared to be lower (as indicated by higher respiration and lower proportions of C in aggregate occluded POM) beneath species with higher tissue calcium contents. The proportion of C in mineral associated SOM and bulk soil ∆14C, though, were negligibly dependent on tree species traits, likely reflecting an insensitivity of some SOM pools to decadal scale shifts in ecological factors. Strategies aiming to increase soil C stocks may thus focus on particulate C pools, which can more easily be manipulated and are most sensitive to climate change.

show abstract

“…This indicated that these two fractions provided favorable conditions to stabilize and store the residue C. The fLOC and cPOC could remain plant structures during the different stages of decomposition (Courtier-Murias et al, 2013) and be dominated by O-alkyl (Golchin et al, 1994a,b;Mueller et al, 2014;Rabbi et al, 2014a). Therefore, fLOC and cPOC were highly bioavailable and soluble organic matter that are easily diffused into small pores of microaggregates and adsorbed on the surface of mineral surface (Courtier-Murias et al, 2013;Poirier et al, 2014;Tisdall and Oades, 1982).…”

Section: Contribution Of Residue Carbon To the Physical Fractions Of mentioning

confidence: 97%

Distribution and storage of crop residue carbon in aggregates and its contribution to organic carbon of soil with low fertility

Zhuang

et al. 2016

Soil and Tillage Research

View full text Add to dashboard Cite

Bioavailability and isotopic composition of CO2 released from incubated soil organic matter fractions

Cited by 47 publications

References 50 publications

Temperature response of permafrost soil carbon is attenuated by mineral protection

Temperature response of permafrost soil carbon is attenuated by mineral protection

Soil organic carbon stability in forests: Distinct effects of tree species identity and traits

Distribution and storage of crop residue carbon in aggregates and its contribution to organic carbon of soil with low fertility

Contact Info

Product

Resources

About