The abandonment of the arable land is a common phenomenon in Romania mostly in hill and mountain area, but sometimes is present in lowland area on small patches of land or on fields characterised by features that make their cultivation difficult. The succession of the ex-arable land to grassland is very frequent, but the duration of the process is dependent by many variables. The duration of the succession from abandoned arable land to grassland is important in the ecological restoration of these land surfaces, because in this way these fields can provide again ecological and economical services. The purpose of this research is to evaluate an ex-arable grassland surface uncultivated by 7 years for the assessment of the progress of the vegetation succession. The researches were developed on an ex-arable grassland plot from Sacoșu Turcesc, Timiș County abandoned from cultivation since 2012. The plot is bordered on a side by the road, on other side by railroad and on other side by arable land. The vegetation data were collected in 2018. Vegetation surveys were done using the linear point quadrate method [DAGET & POISSONET, 1971]. There was analysed the considering the following aspects: floristic composition based on the main grassland functional groups (grasses, legumes, forbs, rushes and sedges and shrubs and trees); biodiversity (species richness, Shannon index and Simpson index); ecological spectres (phytogeographical elements, life-forms, and indicator values for light, temperature, moisture, soil pH and nitrogen); and typological classification of the vegetation. The results regarding the floristic composition had evidenced a vegetation cover specific for permanent grassland, the perennial grasses being dominant. The results regarding biodiversity were highlighted high values. The structure of the vegetation by biogeographical elements shows high complexity, but the number and contribution of the adventive species was very low, contrary to our expectations. The vegetation structure by life-forms was from far dominated by the hemicryptophyte species, as is in the case of permanent grasslands. The indicator values for nitrogen suggest the former cultivation of the land due to the presence of some species with high and very high demands for this element, but this situation can be found also in the case of eutrophic and even mesotrophic permanent grasslands. The successful and rapid succession process can be associated with the soil seed-bank and to the vicinity of the vegetation stripes from the edge of the road and railroad.

ex-arable grassland, succession, biogeographical elements, ecological indicator values

field crops and pastures

Presentation: poster