In this paper, we analysed the effect of habitat reconstructions on some parameters characterizing the carbon exchange processes of ecosystems. Besides extending our knowledge on the ecophysiological functioning of different plant communities, our work was motivated by international policy goals as well: a considerable amount of degraded ecosystems and their services was declared in the European Union to be reconstructed in the next few years. These kinds of projects need detailed impact analyses and a methodological grounding. We would like to contribute to these goals with the results of field measurements carried out in an extensive habitat reconstruction area in the Egyek-Pusztakócs habitat complex (Hortobágy National Park, Eastern Hungary). In this paper, we analysed the results of carbon and nitrogen contents of soils and biomass samples and the average net ecosystem exchange values of the investigated ecosystem types. Our results show that natural or near-natural, well-structured grasslands have an outstanding carbon sequestration and storing potential in the studied landscape type, the restored grasslands lag behind in every parameters. In the process of secondary succession, the carbon exchange characteristics of the restored grasslands seem to follow mainly the species composition, and the effects of land management can modify the effects of regeneration from the point of view of ecophysiological functioning
