Long-term dynamics of carbon emission in artificial soil structures underneath lawns in steppe zone conditions

The article considers the issues of carbon emission by soil structures of different composition functioning in the conditions of urban landscapes of the steppe zone. The study was conducted on the basis of an experimental station for the study of soil constructions, created in 2020 in the Botanical Garden of the Southern Federal University (SFU) using lawn grasses as a vegetation cover. The background area was Haplic Chernozem of the “Priazovskaya steppe” exposition with restored steppe vegetation in the final stage of ecological succession. As a result of long-term monitoring the dependence of carbon emission on hydrothermal conditions was studied: the highest values were observed at humidity of 20–30% and rooting layer temperature of 25–35°C. The main differences in the emission dynamics are caused by the genesis of materials composing the RAT horizon. The intensity of carbon emission by soil structures formed on the basis of peat in the first year was significantly higher (up to 25 g С/(m2 day)); interquartile range – 5.9–13.7 g С/(m2 day)) than in Control sites (up to 17.5 g С/(m2 day); interquartile range – 4.7–12.0 g С/(m2 day)) and in soil structures created on the basis of dark Chernozem topsoil (up to 15 g С/(m2 day); interquartile range – 2.5–7.6 g С/(m2 day)).