Dataset Information

Flow of CO₂ from soil may not correspond with CO₂ concentration in soil.

ABSTRACT: The relationship between CO₂ flow from soil and soil CO₂ concentration was investigated at 72 permanent sampling points at two forested post-mining sites in the northwest of the Czechia. Based on the entire data set (72 points sampled monthly during the growing season), CO₂ flow from the soil was positively correlated with soil CO₂ concentration. CO₂ concentration in deeper soil layers was positively correlated with root biomass and negatively correlated with soil microbial respiration. In individual sampling points relationship between CO₂ flow and soil CO₂ concentration varied from being significantly positive (30% of points) to significantly negative (7%) but mostly being non-significant (63%). The positive correlation occurred at points with high root biomass in deeper soil layers, while the negative correlation occurred at points with high soil microbial respiration per cm³ of soil. Laboratory experiments showed that the CO₂ produced by microbial respiration can reduce microbial respiration but that CO₂ produced by root respiration did not reduce root respiration. The results indicate that when soil ventilation is poor, microbial respiration can sufficiently increase soil CO₂ concentration so as to reduce microbial respiration, which greatly increases the variability in the relationship between CO₂ flow from soil and soil CO₂ concentration.

SUBMITTER: Frouz J

PROVIDER: S-EPMC6031679 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Flow of CO2 from soil may not correspond with CO2 concentration in soil.

Frouz Jan J Bujalský Luděk L

Scientific reports 20180704 1

The relationship between CO2 flow from soil and soil CO2 concentration was investigated at 72 permanent sampling points at two forested post-mining sites in the northwest of the Czechia. Based on the entire data set (72 points sampled monthly during the growing season), CO2 flow from the soil was positively correlated with soil CO2 concentration. CO2 concentration in deeper soil layers was positively correlated with root biomass and negative ...[more]

PMID: 29973618

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Dataset Information

Flow of CO₂ from soil may not correspond with CO₂ concentration in soil.

Publications

Flow of CO<sub>2</sub> from soil may not correspond with CO<sub>2</sub> concentration in soil.

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