Recent changes in agriculture (intensification or abandonment) have resulted in a critical reduction of steppe-like grasslands in Eastern Europe. These grasslands harbor an extraordinarily high diversity of plants and invertebrates, including endemics, and are considered refugia for numerous threatened open-land species. We examined species richness, and abundance, proportion of open-land, endemic and threatened vascular plants, gastropods, and diurnal and nocturnal Lepidoptera in six different vegetation types all originating from steppe-like grasslands in Transylvania, Romania. Vegetation types included extensively grazed pastures (initial stage), three seral stages of succession (early stage of abandoned grassland, abandoned grassland with shrubs, and mature forest), and two human-made grassland alterations, namely abandoned vineyards and Pinus plantations. A total of 852 species (291 vascular plants, 24 gastropods, 129 diurnal and 408 nocturnal Lepidoptera) were found in the 22 study sites. The four taxonomic groups differed in their response to the abandonment of steppe-like grassland, except that species richness of plants and diurnal Lepidoptera were positively correlated. The complementarity of species composition increased with successional age in all taxonomic groups examined. The number of characteristic open-land species decreased with successional age in plants and gastropods. All investigated vegetation types harbored threatened (red-listed) species. Endemic species were found in all vegetation types except mature forests and Pinus plantations. All Transylvanian endemics and the majority of threatened species found were open-land species. Extensively cultivated vineyards, which have been abandoned for two to three decades, also maintained high plant and invertebrate diversities, comparable to those of the corresponding stages of grassland succession. In contrast, Pinus plantations (a recent grassland alteration) have changed habitat quality and will have a devastating effect on the unique, indigenous diversity of these steppe-like grasslands as soon as the canopy closes. To prevent losses of characteristic species, we suggest a rotational grassland management program that maintains different seral stages. Succession to mature forest and additional Pinus plantations should be prevented. Resumen: Cambios recientes en la agricultura (intensificación o abandono) han resultado en la reducción crítica de pastizales similares a estepas en Europa Oriental. Estos pastizales albergan una diversidad extraordinariamente alta de plantas y animales, incluyendo endémicos, y son considerados refugios para numerosas Cremene et al. Biodiversity in Eastern European Grasslands 1607 especies amenazadas. Examinamos la riqueza y abundancia de especies, la proporción de plantas vasculares, gasterópodos y Lepidoptera diurnos y nocturnos amenazados y endémicos en seis tipos de vegetación diferentes pero originados a partir de pastizales similares a estepas en Transilvania, Rumania. Los tipos de vegetación incluyeron pastizal...

No abstract

Alpine grasslands in the Southern Carpathian Mts, Romania, harbour an extraordinarily high diversity of plants and invertebrates, including Carpathic endemics. In the past decades, intensive sheep grazing has caused a dramatic decrease in biodiversity and even led to eroded soils at many places in the Carpathians. Because of limited food resources, sheep are increasingly forced to graze on steep slopes, which were formerly not grazed by livestock and are considered as local biodiversity hotspots. We examined species richness, abundance and number of endemic vascular plants and terrestrial gastropods on steep slopes that were either grazed by sheep or ungrazed by livestock in two areas of the Southern Carpathians. On calcareous soils in the Bucegi Mts, a total of 177 vascular plant and 19 gastropod species were recorded. Twelve plant species (6.8%) and three gastropod species (15.8%) were endemic to the Carpathians. Grazed sites had lower plant and gastropod species richness than ungrazed sites. Furthermore, grazed sites harboured fewer gastropod species endemic to the Carpathians than ungrazed sites. On acid soils in the Fagaras Mts, a total of 96 vascular plant and nine gastropod species were found. In this mountain area, however, grazed and ungrazed sites did not differ in species richness, abundance and number of endemic plant and gastropod species. Our findings confirm the high biodiversity of grasslands on steep slopes in the Southern Carpathian Mts and caution against increasing grazing pressure in these refuges for relic plants and gastropods as well as for other invertebrates.