FEATURES OF CARBON SEQUESTRATION IN SIBERIAN LARCH FOREST STANDS IN THE SOUTHERN FOREST-STEPPE OF THE OMSK REGION

Relevance and objectives. Modern climate change attracts close attention to the study of climate-regulating functions of forest ecosystems. Of particular importance in this regard are coniferous forests, which are widespread in our country and form a significant share (up to 80%) of forest plantations. For the first time in the conditions of the Omsk region, carbon reserves in Siberian larch stands growing on the territory of the carbon polygon (Omsk) and forest fund lands were studied. The purpose of the work is a comparative assessment of carbon reserves in the pools of phytomass of the stand, forest litter and soil organic matter in Siberian larch stands (Larix sibirica Ledebur) growing in different areas of the southern forest-steppe of the Omsk region. Materials and methods. The article is based on the research materials conducted in 2022–2023 on the territory of larch stands in various areas of the southern forest-steppe of the Omsk region – at the carbon testing ground of Omsk State Agrarian University (Omsk) and near the village of Kordon. Two test plots were laid out on each site. Carbon stocks in the pools under consideration were calculated according to the Methodological Guidelines for the Quantitative Determination of the Volume of Greenhouse Gas Absorption from 2017. Results. The average long-term and current climatic parameters in the study areas did not differ significantly. The age of the forest stands is 63–70 years. The key factor in the difference in growing conditions between the objects under consideration was the difference in soil type. On the territory of the carbon testing site, the soil is meadow-chernozem, shallow, low-humus, heavy loamy, while near the village of Kordon it is gray forest solodized, shallow, heavy loamy. Differences in soil types determined the difference in the taxation parameters of the larch stands and the difference in carbon reserves in the pools of phytomass and soil organic matter. Carbon reserves in the phytomass of forest stands varied from 47.3 t C ha-1 to 100.6 t C ha-1. The organic carbon reserve in the 0–50 cm layer on the territory of the testing site was 122.2 t C ha-1, while in the soils near the village of Kordon it was 118.8 t C ha-1. Kordon – 108.1 t C ha-1. Conclusion. The revealed differences in the taxation indices of even-aged larch stands and carbon reserves in the pools of stand and soil phytomass are mainly due to differences in soil types. The stock of stem wood in larch stands near the village of Kordon on gray forest soil is significantly higher than on meadow-chernozem soil of the Omsk State Agrarian University testing ground. Higher reserves of soil carbon in the 0–50 cm layer, on the contrary, are characteristic of the testing ground territory.