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The aim of the present study was to investigate changes in (i) nitrogen (N2) fixation, (ii) netnitrification, and (iii) denitrification potentials under different land uses in a small catchment(21 km2) in Balaton Upland, Hungary. Soil samples were collected from the following sixland use types in three replicates: mixed forest (oak and wattle), forest (oak), grapevine,arable land (winter wheat), orchard (apricot), and grassland. All nitrogen cycling experimentswere carried out under dark conditions in a temperature-controlled laboratory environment.The investigations were implemented under three temperatures 10, 20, and 30 ∘C to representthe typical vegetation season temperature range in the investigated catchment. Potentialnitrogen (N2) fixation was measured as ethylene (C2H4) production from acetylene (C2H2)reduction. Potential denitrification rates were measured using the acetylene blocktechnique.Potential N2 fixation was positively correlated with temperature or no change was observed.Rates decreased as temperature was increased from 10 to 20 ∘C in the cases of arable,orchard, and grassland, while did not change in the case of the forest samples. When thetemperature was increased to 30 ∘C, the N2 fixation potentials also increased significantly(p < 0.017) compared to 10 to 20 ∘C. When investigating the net nitrification of the soils,we found negative correlation with temperature increase, the highest values wereretrieved at 10 ∘C (average net nitrification was 0.2793 nmol N g−1 wet weight soilhr−1), while the lowest at 30 ∘C (average net nitrification was −0.0681 nmol N g−1wet weight soil hr−1). Potential denitrification values were the highest at 20 ∘C.Forest soils did not show substantial differences in potential denitrification rateswhile varying temperatures; however, within land uses all values retrieved at theinvestigated temperatures were significantly different (p < 0.0174). Overall, wefound that land use types can significantly influence the soils’ nitrogen cyclingprocesses, especially when fertilizer amendment is regularly applied. Potentialnitrogen cycle components under different land use types, which are less influenced byanthropogenic activities (e.g. forest soils), were found to be less sensitive to temperaturechanges. [ABSTRACT FROM AUTHOR]