ОБСЯГИ ЕМІСІЇ ДІОКСИДУ ВУГЛЕЦЮ З ДЕРНОВОСЕРЕДНЬОПІДЗОЛИСТИХ ГЛЕЮВАТИХ СУПІЩАНИХ ҐРУНТІВ ПІД ЖИТОМ ОЗИМИМ В ХОЛОДНИЙ ПЕРІОД

The article presents the results of studies for carbon dioxide emission amount determination from sod-podzolic gleyed sandy loam soil on water ice sediments under winter rye in the cold period 2015-2016. It was found that during the cold period the investigated soil prodused about 2438 kg of carbon dioxide from 1 hectare (665 kg of carbon). The role of the main factors determining the soil carbon dioxide production processes by the priority of influence is discussed: soil temperature ↔ air temperature ↔ CO2 concentration in the surface air layer. It was found that the correlation coefficients between the volumes of carbon dioxide emission on one hand and the soil temperature and air temperature on the other, were 0,66 and 0,64, respectively. A minimal effect of carbon dioxide concentration in the surface air layer at an altitude of 0,35 m was recorded on the intensity of CO 2 emission from the soil (r = 0,50). It is shown that the weak character of the reciprocal influences between both factors is due to the absence of a clear temporal dynamics of their variation. The established dependence is also a consequence of the regular seasonal slowing down of the winter rye vegetation process. The impact of the soil «freezing – thawing» effect on the carbon dioxide emissions total amount into the atmosphere was detected. It was identified that the increase in CO 2 emissions occurred at specific time intervals in February 2016, was the result of an increase in the its released volume into the atmosphere. It has been established that the fact of the interval shift for the time intensification of soil СО 2 emissions for an earlier period – from the end of February / the beginning of March to the beginning of February in 2016 – is a consequence of global air temperature warming processes.