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Climate-driven shifts in soil temperature and soil moisture are crucial factors that control the ecosystem-atmosphere greenhouse gas (GHG) balance. In the present study, the relationship between CO 2 , CH 4 fluxes and soil moisture content and temperature sensitivity was examined in three dominating types of urban ecosystems: grassland, city park and arable land. The analysis was based on the field measurements at biweekly intervals over a year using a static closed chamber method in Wroclaw urban area, Poland. The observed patterns of land-atmosphere CO 2 and CH 4 exchange varied across land cover types and were strongly influenced by seasonal variations in temperature and soil water content. Emission of CO 2 from grassland and the city park was two times higher than from the arable land. The calculated CH 4 oxidation rate was one and half times higher (p < 0.05) under grassland and the city park as compared to arable land. The estimated Q 10 values ranged between 1.68 and 1.79 for CO 2 and from 1.26 to 1.49 for CH 4 , depending on the ecosystem type. The temperature sensitivity of soil respiration decreased when the temperature was above 24.5 °C across the moisture gradient from 20 to 25 % m/v. Results suggest that despite the urban areas with agricultural land use revealed the lowest CO 2 fluxes compared to grassland and city park, the former showed the lowest seasonal mean CH 4 oxidation. This indicates that with ongoing warming, the higher Q 10 of CO 2 production vs. CH 4 oxidation will further shift the carbon balance towards the source and this shift will be especially critical for arable lands in urban areas. • The peak fluxes of CO 2 were closely linked to maximums in soil moisture and temperature. • With temperature increase the sensitivity of CO 2 flux and CH 4 uptake to temperature decreased by 14 and 23 %. • Negative CH 4 fluxes indicated uptake which decreased from park and grassland to arable land. • Model prediction of GHGs was highly susceptible to temperature changes in range of 19–23 °C. [ABSTRACT FROM AUTHOR]