CO2-Emissions from agrochernozems of dispersed carbonateTugnuibasin and agrochernozems of quasi-clayYeravninsky basin of westernTransbaikaliawere studied.To compareCO2-emissions from soils, the virginland variants of the same name are taken.The aimof the study is to quantify and comparatively evaluate theproduction of carbon dioxide from arable chernozems with contrasting temperatureand moisture conditions.The measurement ofCO2fluxes from thesoil was carried out by a closed chamber method witha portable infraredCO2gas analyzerAZ7752 (AZInstrumentCorp.,Taiwan).CO2-emissions were largely dependent on hydrothermalconditions.Its minimum at the beginning of the growing seasonwas associated with the effect of low soil temperatures, themaximum was more often noted after precipitation.The peaks ofCO2-emissions coincided with an increase in temperature and humidityfromJune to earlyAugust, in conditions of a lackof readily available moisture, and were also associated with ahumidification regime.The limiting factor of theCO2flux forquasi-clay chernozems was the soil temperature, for dispersed carbonate chernozems–humidity.It has been established that the totalCO2-emission in arable soils is significantly less than in virginsoils, this is explained by the peculiarities of the agrogenicenvironment.Arable soils are warmer in summer, and they cooldown more and deeper in winter.The transformation of thewater regime occurs in the direction of reducing moisture andincreasing its contrast during the warm period.The total carbonloss index varies in a series: dispersed-carbonate chernozem→quasi-claychernozem, virgin soil→arable land.