CH4 and CO2 production below two contrasting peatland micro-relief forms: An inhibitor and δ13C study

Krohn, Johannes; Lozanovska, Ivana; Kuzyakov, Yakov; Parvin, Shahnaj; Dorodnikov, Maxim

doi:10.1016/j.scitotenv.2017.01.192

Cited by 24 publications

(9 citation statements)

References 59 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…13 C‰ was significantly positively correlated with depth ( 13 C becomes increasingly enriched with depth), whereas CH 4 production showed no decreasing trend with depth. Additionally, the acetoclastic hydrogenotrophic pathways of methanogenesis allow for microbial activities that are more independent of the 13 C‰ values of SOM 41 . Previous studies suggested that the availability of labile substrates is one of the limiting factors for methanogenesis 12 , 42 .…”

Section: Discussionmentioning

confidence: 99%

Greenhouse gas released from the deep permafrost in the northern Qinghai-Tibetan Plateau

et al. 2018

Sci Rep

View full text Add to dashboard Cite

Deep carbon pool in permafrost regions is an important component of the global terrestrial carbon cycle. However, the greenhouse gas production from deep permafrost soils is not well understood. Here, using soils collected from 5-m deep permafrost cores from meadow and wet meadow on the northern Qinghai-Tibetan Plateau (QTP), we investigated the effects of temperature on CO2 and N2O production under aerobic incubations and CH4 production under anaerobic incubations. After a 35-day incubation, the CO2, N2O and CH4 production at −2 °C to 10 °C were 0.44~2.12 mg C-CO2/g soil C, 0.0027~0.097 mg N-N2O/g soil N, and 0.14~5.88 μg C-CH4/g soil C, respectively. Greenhouse gas production in deep permafrost is related to the C:N ratio and stable isotopes of soil organic carbon (SOC), whereas depth plays a less important role. The temperature sensitivity (Q10) values of the CO2, N2O and CH4 production were 1.67–4.15, 3.26–5.60 and 5.22–10.85, without significant differences among different depths. These results indicated that climate warming likely has similar effects on gas production in deep permafrost and surface soils. Our results suggest that greenhouse gas emissions from both the deep permafrost and surface soils to the air will increase under future climate change.

show abstract

Section: Discussionmentioning

confidence: 99%

Greenhouse gas released from the deep permafrost in the northern Qinghai-Tibetan Plateau

et al. 2018

Sci Rep

View full text Add to dashboard Cite

show abstract

“…The differences in C discrimination between the two pathways are greater for the hydrogenotrophic compared to the acetoclastic pathway, resulting in more depleted (−110 ‰ to −60 ‰) and more enriched (−60 ‰ to −50 ‰) 13 CH 4 , respectively. This has been confirmed in field and laboratory experiments (Conrad et al, 2010;Krohn et al 2017;Krzycki et al, 1987;Sugimoto and Wada, 1993;Whiticar et al, 1986;Whiticar, 1999). Baldwin et al (2006) also found that saltwater additions promoted the hydrogenotrophic methanogenic pathway.…”

Section: Treatmentmentioning

confidence: 56%

Saltwater reduces potential CO<sub>2</sub> and CH<sub>4</sub> production in peat soils from a coastal freshwater forested wetland

et al. 2019

View full text Add to dashboard Cite

Abstract. A major concern for coastal freshwater wetland function and health is the effects of saltwater intrusion on greenhouse gas production from peat soils. Coastal freshwater forested wetlands are likely to experience increased hydroperiod with rising sea level, as well as saltwater intrusion. These potential changes to wetland hydrology may also alter forested wetland structure and lead to a transition from forest to shrub/marsh wetland ecosystems. Loss of forested wetlands is already evident by dying trees and dead standing trees (“ghost” forests) along the Atlantic coast of the US, which will result in significant alterations to plant carbon (C) inputs, particularly that of coarse woody debris, to soils. We investigated the effects of salinity and wood C inputs on soils collected from a coastal freshwater forested wetland in North Carolina, USA, and incubated in the laboratory with either freshwater or saltwater (2.5 or 5.0 ppt) and with or without the additions of wood. Saltwater additions at 2.5 and 5.0 ppt reduced CO2 production by 41 % and 37 %, respectively, compared to freshwater. Methane production was reduced by 98 % (wood-free incubations) and by 75 %–87 % (wood-amended incubations) in saltwater treatments compared to the freshwater plus wood treatment. Additions of wood also resulted in lower CH4 production from the freshwater treatment and higher CH4 production from saltwater treatments compared to wood-free incubations. The δ13CH4-C isotopic signature suggested that, in wood-free incubations, CH4 produced from the freshwater treatment originated primarily from the acetoclastic pathway, while CH4 produced from the saltwater treatments originated primarily from the hydrogenotrophic pathway. These results suggest that saltwater intrusion into coastal freshwater forested wetlands will reduce CH4 production, but long-term changes in C dynamics will likely depend on how changes in wetland vegetation and microbial function influence C cycling in peat soils.

show abstract

“…Acidic wetlands are the most extensive type of northern wetlands in Europe and North America and contribute up to 50% of the global production of the atmospheric greenhouse gas, CH 4 [1,2]. Global warming is expected to increase the rate of emission of CH 4 from these peats and for this reason research into the mechanisms of CH 4 production has received widespread attention in recent years [3][4][5][6]. Methane can either be generated by hydrogenotrophic methanogenesis through the reduction of CO 2 by molecular hydrogen (CO 2 + 4H 2 → CH 4 + 2H 2 O) or by acetoclastic methanogenesis through acetate cleavage (CH 3 COOH → CH 4 + CO 2 ).…”

Section: Introductionmentioning

confidence: 99%

Significance of the High Abundance of Pentacyclic Triterpenyl and Hopenyl Acetates in Sphagnum Peat Bogs from Northern Spain

et al. 2019

View full text Add to dashboard Cite

Global warming is expected to increase the rate of CH4 emission from acidic peatlands leading to an increased interest on its mechanisms of formation. The main routes are through the reduction of CO2 by molecular hydrogen and through the cleavage of acetate. A predominance of the former, a reaction which also competes with homoacetogenesis to form acetate, may enrich the media in acetate, which could potentially be incorporated in the peat molecular markers. Acetates of triterpenoid biomarkers have been identified in peats and lake sediments and related to the input of higher plants. Nevertheless, the acetyl derivatives are found in very low amounts in fresh plants and in much lower amount than other derivatives with alcohol or ketone functional groups. The dichloromethane/methanol extracts of Asturian peat bog profiles (North Spain) were analyzed using gas chromatography/mass spectrometry (GC/MS) and compound-specific-isotope-analysis (CSIA). They show abundance of acetates of compounds with oleanane, ursane, and lupane skeletons derived from higher plants and with hopane skeleton, which can be considered a characteristic of these peats. Two families of 3-oxyhopenyl acetates with -17(21)- and -22(29)- configurations were detected in the upper part of the peat profiles, having a δ13C isotopic composition enriched by 4‰ compared with that of higher plant triterpenoids, and similar to that of microorganism-derived regular hopanoids. Both the acetate and ketone derivatives with the oxygenated functionality at C-3 were generally present in a given extract and tended to accumulate at certain depth in the profiles and in specific levels. The widespread occurrence of acetyl-derivatives, their higher concentration in the deeper layers of the peat, the fact that the acetates correspond to different compound families of diverse source and the very low amount of acetates identified in Ericaceae-contributing to the peat compared to the alcohols suggest that they were formed in the peat under particularly favorable environmental conditions. We postulate that these conditions could have been the existence of a medium enriched in acetic acid produced by the dominance of hydrogenotrophic methanogenesis and/or homoacetogenesis over acetoclastic methanogenesis. This phenomenon that has been preferentially described in Sphagnum bogs at high latitudes, and in the deeper layers of peat, appears to be also present in the temperate peats of the Asturian coast.

show abstract

CH4 and CO2 production below two contrasting peatland micro-relief forms: An inhibitor and δ13C study

Cited by 24 publications

References 59 publications

Greenhouse gas released from the deep permafrost in the northern Qinghai-Tibetan Plateau

Greenhouse gas released from the deep permafrost in the northern Qinghai-Tibetan Plateau

Saltwater reduces potential CO<sub>2</sub> and CH<sub>4</sub> production in peat soils from a coastal freshwater forested wetland

Significance of the High Abundance of Pentacyclic Triterpenyl and Hopenyl Acetates in Sphagnum Peat Bogs from Northern Spain

Contact Info

Product

Resources

About

CH4 and CO2 production below two contrasting peatland micro-relief forms: An inhibitor and δ13C study

Cited by 24 publications

References 59 publications

Greenhouse gas released from the deep permafrost in the northern Qinghai-Tibetan Plateau

Greenhouse gas released from the deep permafrost in the northern Qinghai-Tibetan Plateau

Saltwater reduces potential CO&lt;sub&gt;2&lt;/sub&gt; and CH&lt;sub&gt;4&lt;/sub&gt; production in peat soils from a coastal freshwater forested wetland

Significance of the High Abundance of Pentacyclic Triterpenyl and Hopenyl Acetates in Sphagnum Peat Bogs from Northern Spain

Contact Info

Product

Resources

About

Saltwater reduces potential CO<sub>2</sub> and CH<sub>4</sub> production in peat soils from a coastal freshwater forested wetland