Development of urban green infrastructures (UGI) is considered among the main nature-based solutions for climate mitigation and adaptation in cities; however, the role of urban soils in carbon balance of UGI remains overlooked and likely underestimated. In this research, we observed soil stocks of organic and inorganic carbon and soil carbon dioxide (CO2) emission for the city park “Mothers’ Glory” in Grozny, Chechen Republic, Russia. Soil survey in the park was performed in July 2022. Sampling points were randomly selected within the landscape part of the park. Topsoil (0–10 cm) samples were collected at sites of irrigated lawns, non-irrigated lawns and non-irrigated lawns with trees. Additional samples from top 50 cm and top 100 cm were collected. Soil respiration was measured in situ at the sites by infrared gas analyzer Li-7810SC during the period April–October 2022 with an average time step 2–3 weeks. In parallel, soil temperature and moisture were observed. Total soil CO2 emission for the observation period was above 0.5 kg Cm−2. Based on the estimated 5.5 years half-life time, C stocks at the managed green areas of Grozny are not resistant to biodegradation, and their vulnerability will likely further increase under ongoing climate change. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.