Relationship between soil CO2 fluxes and soil moisture: Anaerobic sources explain fluxes at high water content

Fairbairn, Linden; Rezanezhad, Fereidoun; Gharasoo, Mehdi; Parsons, Christopher T.; Macrae, Merrin L.; Slowinski, Stephanie; Cappellen, Philippe Van

doi:10.1016/j.geoderma.2023.116493

Cited by 17 publications

(9 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is a significant new finding that methanogenesis was also activated after Mollisol addition and to the greatest extent in the case of paddy Mollisol erosion. Under oxic conditions, anaerobic respiration generating CO 2 was found to occur frequently in agricultural soils, but without appreciable efflux of CH 4 . Our results suggest that coemission of CO 2 and CH 4 may have been triggered in the Mollisol erosion process, for example, via the simplified methanogenic reaction below, with CH 4 :CO 2 molar ratio of 1:1: C 6 H 12 O 6 → normal3CH 4 + normal3CO 2 …”

Section: Resultsmentioning

confidence: 70%

Section: Methodsmentioning

confidence: 99%

“…Basic water parameters were monitored with a multichannel water quality probe (HQ40d, HACH). Periodically sampled solution was filtered through 0.45-μm microporous filter membrane, and then concentrations of dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC) were determined with an elemental analyzer (Vario EL TOC cube, Germany) …”

Section: Methodsmentioning

confidence: 99%

“…A predetermined mass of fresh, homogenized Mollisol samples was first moistened with a small amount of corresponding river water (composition shown in Table S2) to saturated moisture state (approximately 40 wt %) and then preincubated in a 500 mL glass incubation reactor at 20 °C for 3 d. 38 Thereafter, 360 mL of the same river water was added to the reactor and mixed with the Mollisol sample thoroughly by gentle stirring. All batches were then covered tightly with aluminum foils and incubated in dark walk-in environmental chamber for 20 d, continuously exposed to sterile air by controlled gas flow, and stirred slowly to mimic dynamic river flow.…”

Section: Mesocosm Incubation Experimentsmentioning

confidence: 99%

“…Periodically sampled solution was filtered through 0.45-μm microporous filter membrane, and then concentrations of dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC) were determined with an elemental analyzer (Vario EL TOC cube, Germany). 38 Concentrations of CO 2 , CH 4 , and O 2 collected from the reactor headspace were determined with a gas chromatograph (Shimadzu Model GC-2014 Plus), which was equipped with a Porapak T packed column and a flame ionization detector and methanizer. Further details of gas analyses are presented in Text S4−3.…”

Section: Determination Of Watermentioning

confidence: 99%

See 4 more Smart Citations

Mollisol Erosion-Driven Efflux of Energetic Organic Carbon and Microflora Increases Greenhouse Gas Emissions from Cold-Region Rivers

Li,

Pi,

Van Cappellen

et al. 2024

Environ. Sci. Technol.

Self Cite

View full text Add to dashboard Cite

Massive soil erosion occurs in the world’s Mollisol regions due to land use change and climate warming. The migration of Mollisol organic matter to river systems and subsequent changes in carbon biogeochemical flow and greenhouse gas fluxes are of global importance but little understood. By employing comparative mesocosm experiments simulating varying erosion intensity in Mollisol regions of northeastern China, this research highlights that erosion-driven export and biomineralization of terrestrial organic matter facilitates CO2 and CH4 emission from receiving rivers. Stronger Mollisol erosion, as represented by a higher soil-to-water ratio in suspensions, increased CO2 efflux, particularly for the paddy Mollisols. This is mechanistically attributable to increased bioavailability of soluble organic carbon in river water that is sourced back to destabilized organic matter, especially from the cultivated Mollisols. Concurrent changes in microbial community structure have enhanced both aerobic and anaerobic processes as reflected by the coemission of CO2 and CH4. Higher greenhouse gas effluxes from paddy Mollisol suspensions suggest that agricultural land use by supplying more nitrogen-containing, higher-free-energy organic components may have enhanced microbial respiration. These new findings highlight that Mollisol erosion is a hidden significant contributor to greenhouse gas emissions from river water, given that the world’s four major Mollisol belts are all experiencing intensive cultivation.

show abstract

Section: Resultsmentioning

confidence: 70%

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: Mesocosm Incubation Experimentsmentioning

confidence: 99%

Section: Determination Of Watermentioning

confidence: 99%

See 3 more Smart Citations

Mollisol Erosion-Driven Efflux of Energetic Organic Carbon and Microflora Increases Greenhouse Gas Emissions from Cold-Region Rivers

Li,

Pi,

Van Cappellen

et al. 2024

Environ. Sci. Technol.

Self Cite

View full text Add to dashboard Cite

show abstract

Response of soil CO₂ emissions and water‐carbon use efficiency of winter wheat to different straw returning methods and irrigation scenarios

Liu,

Gao,

Zhang

et al. 2023

J Sci Food Agric

View full text Add to dashboard Cite

BACKGROUNDThe shortage of water resources and the increase of greenhouse gas emissions from soil seriously restrict the sustainable development of agriculture. Under the premise of ensuring stable yield of winter wheat through reasonable irrigation scenario, finding a suitable straw returning method will have a positive effect on agricultural carbon sequestration and emission reduction in North China Plain (NCP).RESULTSStraw burying (SR) and straw mulching (SM) were adopted based on traditional tillage under in the winter wheat growing season of 2020–2021 and 2021–2022. Three irrigation scenarios were used for each straw returning method: no irrigation (I0), irrigation 60 mm (I1) at jointing stage and irrigation of 60 mm each at the jointing and heading stages (I2). Soil moisture, soil respiration rate, cumulative soil CO2 emissions, yield, water use efficiency (WUE) and soil CO2 emission efficiency (CEE) were mainly studied. The results showed that compared to SM, SR improved the utilization of soil water and enhanced soil carbon sequestration. SR reduced soil respiration rate and cumulative soil CO2 emissions in two winter wheat growing seasons, and increased yield by increasing spike numbers. In addition, with an increase in the amount of irrigation, soil CO2 emissions and yield increased. Under SR‐I1 treatment, WUE and CEE were the highest. SR‐I1 increases crop yields while reducing soil CO2 emissions.CONCLUSIONThe combination of straw burying and irrigation 60 mm at jointing stage is a suitable straw‐returning irrigation scenario, which can improve water use and reduce soil CO2 emission in NCP.This article is protected by copyright. All rights reserved.

show abstract

Organic soil greenhouse gas flux rates in hemiboreal old-growth Scots pine forests at different groundwater levels

Samariks,

Ķēniņa,

Īstenais

et al. 2024

Eur J Forest Res

View full text Add to dashboard Cite

Tree biomass and soils (especially organic soils) are significant carbon pools in forest ecosystems, therefore forest management practices, in order to ensure carbon storage in these pools and to mitigate climate change, are essential in reaching climate neutrality goals set by the European Union. Overall studies have focused on diverse aspects of forest carbon storage and greenhouse gas (GHG) fluxes from mineral soils, and recently also from organic soils. However, the information about old-growth forests and the long-term effects of drainage on GHG fluxes of organic soils is missing. Additionally, a large proportion of Scots pine (Pinus sylvestris L.) forests on organic soils in the hemiboreal region are drained to regulate groundwater level and to improve above-ground carbon storage. The study aims to assess the intra-annual dynamics of soil carbon dioxide (CO2) and methane (CH4) fluxes in hemiboreal old-growth Scots pine stands on organic soils with diverse groundwater levels. Six old-growth stands (130–180 years old) were evaluated. In old-growth forests, the main source of soil CO2 emissions is ground vegetation and tree roots (autotrophic respiration), while heterotrophic respiration contributes to almost half (41%) of the total forest floor ecosystem (soil) respiration. The total forest floor respiration and soil heterotrophic respiration are mainly affected by soil temperature, with minor but statistically significant contribution of groundwater level (model R2 = 0.78 and R2 = 0.56, respectively). The CO2 fluxes have a significant, yet weak positive relationship with groundwater level (RtCO2 R2 = 0.06 RhCO2 R2 = 0.08). In contrast, total soil CH4 uptake or release depends primarily on groundwater level fluctuations, with a minor but significant contribution of soil temperature (model R2 = 0.67). CH4 flux has high variability between stands.

show abstract

Relationship between soil CO2 fluxes and soil moisture: Anaerobic sources explain fluxes at high water content

Cited by 17 publications

References 72 publications

Mollisol Erosion-Driven Efflux of Energetic Organic Carbon and Microflora Increases Greenhouse Gas Emissions from Cold-Region Rivers

Mollisol Erosion-Driven Efflux of Energetic Organic Carbon and Microflora Increases Greenhouse Gas Emissions from Cold-Region Rivers

Response of soil CO₂ emissions and water‐carbon use efficiency of winter wheat to different straw returning methods and irrigation scenarios

Organic soil greenhouse gas flux rates in hemiboreal old-growth Scots pine forests at different groundwater levels

Contact Info

Product

Resources

About

Relationship between soil CO2 fluxes and soil moisture: Anaerobic sources explain fluxes at high water content

Cited by 17 publications

References 72 publications

Mollisol Erosion-Driven Efflux of Energetic Organic Carbon and Microflora Increases Greenhouse Gas Emissions from Cold-Region Rivers

Mollisol Erosion-Driven Efflux of Energetic Organic Carbon and Microflora Increases Greenhouse Gas Emissions from Cold-Region Rivers

Response of soil CO2 emissions and water‐carbon use efficiency of winter wheat to different straw returning methods and irrigation scenarios

Organic soil greenhouse gas flux rates in hemiboreal old-growth Scots pine forests at different groundwater levels

Contact Info

Product

Resources

About

Response of soil CO₂ emissions and water‐carbon use efficiency of winter wheat to different straw returning methods and irrigation scenarios