Organic matter stability in forest-tundra soils after wildfire

No Thumbnail Available
File version
Author(s)
Filimonenko, E
Uporova, M
Prikhodko, N
Samokhina, N
Belyanovskaya, A
Kurganova, I
Lopes de Gerenyu, V
Merino, C
Matus, F
Chen, C
Alharbi, SA
Soromotin, A
Kuzyakov, Y
Griffith University Author(s)
Primary Supervisor
Other Supervisors
Editor(s)
Date
2024
Size
File type(s)
Location
License
Abstract

Wildfires in the north circumpolar region are increasing in response to global warming and raised precipitation irregularity. Beside the short-time effects of wildfires on carbon (C) cycle by CO2 boost, the decreased amounts and availability of remaining organic matter slow down microbial decomposition over mid- and long-term. Our objective was to investigate the effects of low-intensity surface wildfire common in forest-tundra on soil organic matter (SOM) stability. We hypothesized that wildfire crucially increases organic matter stability due to pyrogenic C production, which reduces SOM availability to microorganisms. To prove this hypothesis, we analyzed SOM stability by thermal analysis (thermogravimetry and differential scanning calorimetry) combined with microbial respiration and assessed temperature sensitivity of SOM decomposition. Wildfire in forest-tundra decreased the thermal labile SOM pool by 1.6–1.9 times and increased the most stable SOM pool by 2.1 times in the O-horizon and 1.3 times in the mineral topsoil. Fire increased SOM thermal stability stronger in the O-horizon compared to the mineral topsoil. For the first time, we revealed the relationship between SOM thermal stability and microbial activity in Cryosols. The increased stability of SOM in Cryosols raised temperature sensitivity (Q10) of SOM decomposition by microorganisms, decreased microbial respiration (CO2 efflux) and microbial biomass content. Concluding, wildfires have strong effects on soil and microbial properties, leaving predominantly stable organic matter pools, which are less available for microorganisms.

Journal Title

Catena

Conference Title
Book Title
Edition
Volume

243

Issue
Thesis Type
Degree Program
School
Publisher link
Patent number
Funder(s)
Grant identifier(s)
Rights Statement
Rights Statement
Item Access Status
Note
Access the data
Related item(s)
Subject
Persistent link to this record
Citation

Filimonenko, E; Uporova, M; Prikhodko, N; Samokhina, N; Belyanovskaya, A; Kurganova, I; Lopes de Gerenyu, V; Merino, C; Matus, F; Chen, C; Alharbi, SA; Soromotin, A; Kuzyakov, Y, Organic matter stability in forest-tundra soils after wildfire, Catena, 2024, 243, pp. 108155

Collections