<p>We have here assessed the relative importance of global warming and variation in edaphic factors that account for long-term compositional shifts in terrestrial vegetation, distributed throughout a cultural landscape shaped by changes in land use mode and livestock grazing intensity. Twenty-eight semi-permanent plots surveyed in 1966 and assigned to five vegetation types (fen, thicket, heath, mesic/subxeric grassland) were revisited in 2024. Significant temporal differences in species composition were detected in all metacommunities. Except for semi-dry grasslands, a general trend of compositional divergence was observed over time. A significant increase in mean alpha diversity over time was registered only in fens and thickets. Apart from semi-dry grasslands, the divergence and shift in compositional dissimilarities, and the stable/increasing species diversity were driven by successions (in heaths and thickets), soil enrichment/impoverishment (in fens/thickets) and increasing temperatures/drought severity in spring (in mesic grasslands and heaths). The composition and diversity of semi-dry grasslands displayed small variations attributable to natural fluctuations. The synergistic effects of climate warming and decreasing intensity of traditional management on vegetation were contingent on specific ecological characteristics of habitats and historical land use. Unlike much similar research carried out in central-western Europe, no decrease in plant species diversity in any of the studied vegetation types was observed. These findings may be either a sign of stabilising, net effect of climate warming and reduced stocking rates or, a consequence of considerable species extinction debt.</p> Graphical Abstract <p>The small inset map shows the location of the study area within the South-Eastern Carpathian basin and within the Romanian borders. The two side-by-side maps illustrate the noticeable changes in land use that have occurred over the last 58 years. In particular, a strong increase in area covered with grasslands to the detriment of arable croplands and wetlands (fens) is conspicuous by comparing the two maps and the rates of change in the lower table. The compositional trend indicates that, except for the semi-dry grasslands which have maintained their floristic similarity, all the other plant communities within each vegetation type have become more dissimilar. This divergence trend represents the opposite of compositional homogenization, which is often observed in man-managed ecosystems. Finally, the last table column says that plant species diversity has increased over time in fens and tall thickets, while resting unchanged in grasslands and heaths.</p>