Post-pyrogenic carbon dioxide emissions from the edge ecotone depending on the intensity of fire exposure

Abstract

The aim of the study. To assess carbon dioxide emissions during the restoration ecosystems affected to varying degree by fire for further use in determining the dynamic pattern of carbon fluxes.

Location and time of the study. The experiment was conducted at the experimental site located in the Alexandrovsky district of the Vladimir region (56.613045 N, 38.362325 E) from the beginning of May till October 2022.

Methods. The research included the preparation of experimental sites exposed to fires of varying degrees of intensity, the determination of soil carbon dioxide fluxes by the chamber method, and measurements of key environmental indicators (air and soil temperature, soil moisture).

Results. There was a noticeable difference in post-pyrogenic carbon dioxide emissions from sites of varying degrees of burnout. The maximal values of 8.19 ± 5.40 g m^-2 day^-1 were observed at the site of fresh burning, and the minimal values of 1.22 ± 0.520 g m^-2 day^-1 were observed at the site that was exposed to the most intense fire. For the rate of CO₂ emission from soils during the observation period, intra-seasonal variations were identified, which were related to soil temperature and moisture.

Conclusions. The data we obtained on CO₂ emissions at the control site of an undisturbed ecotope correspond to estimates previously obtained by other authors for sod-podzolic soils. CO₂ emissions from the soil during the recovery period after prolonged pyrogenic exposure were significantly lower compared with the control sites and sites affected by the short-term exposure to fire. The restoration of the latter, associated with a significant increase in emission, requires further research to determine the contribution of microbiota to soil respiration during short-term pyrogenic effects similar to those of accidebntal fires of anthropogenic origin.