Tóth, T., Fórizs, I., Kuti, L., Wardell, J.L. 2005. Data on the elements of carbon cycle in a Solonetz and Solonchak soil. Cereal Research Communications. 33: (No.1.) 133-136. Carbon cycle at the studied salt-affected sites shows close relationship between vegetation (plant cover), soil composition and groundwater. The larger plant cover at Apaj resulted in greater soil CO2 concentration and flux, and SOM. All these components are depleted in 13C, therefore the d13C value of DIC at Apaj is significantly more negative than at Zabszék.