Soil carbon dioxide emissions from maize (Zea mays L.) fields as influenced by tillage management and climate*

Emissions of CO2 from the soil are the second-largest component of the global carbon cycle, which has altered the climate and led to climate change. The main aim of this research was to evaluate the direct impact of climate and soil management systems on soil carbon emissions. Thus, CO2 emissions were measured from maize fields located in two different climate regions (continental and semi-arid). The experimental design involved two different soil management systems (conventional tillage [CT], non-tillage [NT]) from two different sites (Debrecen [Hungary], Karaj [Iran]). The results showed that total CO2 emission from the cultivated system (CT) was higher than that from the non-cultivated (NT) one, regardless of the climate region. However, CO2 emissions from agricultural soil in a humid region are significantly different (p < .05) from semi-arid regions, which clearly emphasizes the role of climate conditions in the CO2 emission processes. However, the general linear model reveals that all studied variables (soil management systems, date of measurement, soil temperature, soil water content) had a significant (p < .05) effect on soil carbon emission, where the explained variance was 0.866. The findings of this research stress the importance of NT in CO2 mitigations on the farm scale. However, the output could help to draw up mitigation strategies to minimize the total greenhouse gas emissions from agricultural soil in both countries.