Role of CH4 oxidation, production and transport in forest soil CH4 flux

Tropospheric methane (CH4) is oxidised by soil microbes called methanotrophs. We examined them in soil samples from a pristine Nothofagus forest located in New Zealand. Laboratory incubations indicated the presence of high-affinity methanotrophs that displayed Michaelis–Menton kinetics (Km = 8.4 µL/L where Km is the substrate concentration at half the maximal rate). When the soil was dried from its field capacity water content of 0.34 to 0.16 m3/m3, CH4 oxidation rate increased nearly 7-fold. The methanotrophs were thus metabolically poised for very high activity, but substrate availability was commonly limiting. When water content was held constant, CH4 oxidation rate nearly doubled as temperature increased from 5 to 12°C, a range found in the forest. By contrast, CH4 oxidation rate did not change much from 12 to 30°C, and it was zero at 35°C. When water content and temperature were held constant, the optimal soil pH for CH4 oxidation was 4.4, as found in the forest. Soil disturbance by nitrogen (N) and non-N salt amendment decreased CH4 oxidation rate, but this depended on the amendment species and concentration. The methanotrophs were adapted to native conditions and exhibited a great sensitivity to disturbance.

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Role of rhodium anode in the YSZ-aided CH4 oxidation into syngas

Solid State Ionics ◽

10.1016/s0167-2738(00)00560-9 ◽

2000 ◽

Vol 136-137 (1-2) ◽

pp. 753-759 ◽

Cited By ~ 3

Author(s):

K Sato

Keyword(s):

Ch4 Oxidation

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Gene Transcription in Lactarius quietus-Quercus petraea Ectomycorrhizas from a Forest Soil

Applied and Environmental Microbiology ◽

10.1128/aem.00584-08 ◽

2008 ◽

Vol 74 (21) ◽

pp. 6598-6605 ◽

Cited By ~ 19

Author(s):

P. E. Courty ◽

M. Poletto ◽

F. Duchaussoy ◽

M. Buï¿½e ◽

J. Garbaye ◽

...

Keyword(s):

Gene Expression ◽

Forest Soil ◽

Reverse Transcription ◽

Quercus Petraea ◽

Primary Metabolism ◽

Extraradical Mycelium ◽

Root Tips ◽

Reverse Transcription Pcr ◽

Fungal Genes

ABSTRACT Extracting fungal mRNA from ectomycorrhizas (ECMs) and forest soil samples for monitoring in situ metabolic activities is a significant challenge when studying the role of ECMs in biogeochemical cycles. A robust, simple, rapid, and effective method was developed for extracting RNA from rhizospheric soil and ECMs by adapting previous grinding and lysis methods. The quality and yield of the extracted RNA were sufficient to be used for reverse transcription. RNA extracted from ECMs of Lactarius quietus in a 100-year-old oak stand was used to construct a cDNA library and sequence expressed sequence tags. The transcripts of many genes involved in primary metabolism and in the degradation of organic matter were found. The transcription levels of four targeted fungal genes (glutamine synthase, a general amino acid transporter, a tyrosinase, and N-acetylhexosaminidase) were measured by quantitative reverse transcription-PCR in ECMs and in the ectomycorrhizospheric soil (the soil surrounding the ECMs containing the extraradical mycelium) in forest samples. On average, levels of gene expression for the L. quietus ECM root tips were similar to those for the extraradical mycelium, although gene expression varied up to 10-fold among the samples. This study demonstrates that gene expression from ECMs and soil can be analyzed. These results provide new perspectives for investigating the role of ectomycorrhizal fungi in the functioning of forest ecosystems.

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Forest soil microbial functional patterns and response to a drought and warming event: Key role of climate–plant–soil interactions at a regional scale

Soil Biology and Biochemistry ◽

10.1016/j.soilbio.2013.12.003 ◽

2014 ◽

Vol 70 ◽

pp. 1-4 ◽

Cited By ~ 14

Author(s):

Alexia Pailler ◽

Michel Vennetier ◽

Franck Torre ◽

Christian Ripert ◽

Daniel Guiral

Keyword(s):

Forest Soil ◽

Regional Scale ◽

Soil Microbial ◽

Plant Soil ◽

Functional Patterns ◽

Plant Soil Interactions

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Carbon storage in post-mining forest soil, the role of tree biomass and soil bioturbation

Biogeochemistry ◽

10.1007/s10533-009-9313-0 ◽

2009 ◽

Vol 94 (2) ◽

pp. 111-121 ◽

Cited By ~ 91

Author(s):

Jan Frouz ◽

Václav Pižl ◽

Emil Cienciala ◽

Jiří Kalčík

Keyword(s):

Forest Soil ◽

Carbon Storage ◽

Tree Biomass

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Larix decidua and additional light affect the methane balance of forest soil and the abundance of methanogenic and methanotrophic microorganisms

FEMS Microbiology Letters ◽

10.1093/femsle/fnz259 ◽

2019 ◽

Vol 366 (24) ◽

Cited By ~ 1

Author(s):

Nadine Praeg ◽

Larissa Schwinghammer ◽

Paul Illmer

Keyword(s):

Light Intensity ◽

Forest Soil ◽

Light Exposure ◽

Methanogenic Archaea ◽

Larix Decidua ◽

Bulk Soil ◽

Ch4 Oxidation ◽

Plant Microbe Interaction ◽

Methane Oxidizing Bacteria ◽

The Impact

ABSTRACT Due to the activity of methane-oxidizing bacteria, forest soils are usually net sinks for the greenhouse gas methane (CH4). Despite several hints that CH4 balances might be influenced by vegetation, there are only few investigations dealing with this connection. Therefore, we studied this soil–plant–microbe interaction by using mesocosm experiments with forest soil and Larix decidua, a common coniferous tree species within the Alps. Gas measurements showed that the presence of L. decidua significantly reduced CH4 oxidation of the forest soil by ∼10% (−0.95 µmol m−2 h−1 for soil vs −0.85 µmol m−2 h−1 for soil plus L. decidua) leading to an increased net CH4 balance. Increased light intensity was used to intensify the influence of the plant on the soil's CH4 balance. The increase in light intensity strengthened the effect of the plant and led to a greater reduction of CH4 oxidation. Besides, we examined the impact of L. decidua and light on the abundance of methanogens and methanotrophs in the rhizosphere as compared with bulk soil. The abundance of both methane-oxidizing bacteria and methanogenic archaea was significantly increased in the rhizosphere compared with bulk soil but no significant response of methanogens and methanotrophs upon light exposure was established.

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