Dynamics of Carbon Dioxide Emissions from Chernozem Soils under a Forest Shelterbelt and Adjacent Arable Land in the Southern Forest-Steppe

The aim of this study was to quantitatively assess the dynamics of carbon dioxide emissions from the chernozems of the southern forest-steppe under conditions of different agricultural use in the Kamennaya Steppe: under a long-functioning forest shelterbelt and on adjacent arable lands. The studies were conducted during the 2024 growing season using a closed chamber method. It has been established that the average rate of CO2 emission was significantly higher in the forest shelterbelt (2.68 ± 1.02 μmol CO2/m2 s) than on arable land (1.83 ± 1.31 μmol CO2/m2 s), except in June. According to the results of multiple linear regression, in the forest shelterbelt area, temperature, moisture, and their interaction had a significant impact on emissions (R2 = 0.750, p < 0.0001), whereas in arable land the statistically significant predictors were temperature and its interaction with moisture (R2 = 0.767, p < 0.0001). An assessment of the contribution of heterotrophic and autotrophic respiration showed that in the forest shelterbelt the share of microbial respiration accounted for more than half of the total flow (58.6%). The results allow us to quantitatively characterize the differences in the intensity of carbon dioxide emissions from chernozems under two types of land use within the same agricultural landscape.