Reference ecosystems for riparian forest restoration: are there any patterns of biodiversity, forest structure and functional traits?

The use of natural ecosystems as a goal to be achieved and the selection of indicators to evaluate restoration success are controversial issues in both Science and practice of ecosystem restoration. Four remnants of riparian vegetation were assessed in the region of Seasonally Semideciduous Forest in order to verify if some attributes of this plant community varied among sites and if they could be used as reference for this region. Ten plots of 100 m(2) were established in each site and woody plants with height >= 50 cm, separated in upper stratum (dbh >= 5 cm) and lower stratum (dbh < 5 cm), and classified by functional traits, rarity and status in red lists. Terrestrial ferns, lianas and trees with epiphytes were all accounted. Density (in both layers, and trees with epiphythes), basal area, and canopy cover did not differ among areas. Rarefied richness and total estimated richness, as well as the proportion of species by dispersal syndrome, shade tolerance, growth rhythm, and rarity follow a regional pattern, which can be considered as reference for riparian forests in this ecological region. Whether or not these values can be used as restoration goals depends on: 1) long term assessment of restoration success, and 2) scientific evidence that restored ecosystems can reach such values.