Aims We offer a first classification of South Brazilian grasslands (Campos Sulinos) based on quantitative vegetation data and describing grassland types in terms of dominant and indicator species. Location South Brazilian grasslands (Paraná, Santa Catarina, Rio Grande do Sul states). Methods We described vegetation plots in 167 sampling units throughout the region using a stratified nested design, totalizing 1,502 1 m² quadrats. We classified vegetation using cluster analysis based on Bray–Curtis dissimilarities, establishing three vegetation types and ten subtypes. We conducted indicator species analysis within the resulting subtypes, and for all possible combinations of subtypes. Results In the cluster analyses, a clear separation of poorly drained grasslands from the drier sites appeared. Further, a clear distinction between grasslands in the South Brazilian highland region, situated in the Atlantic Forest biome, and the grasslands of the Pampa biome, to the south, emerged, reflecting climatic and management differences. Highland grasslands showed lower species cover dominance, while in the Pampa, Paspalum notatum clearly was the most important species and the abundance of exotic species was higher. Conclusions Our study provides the first classification of South Brazilian grasslands based on quantitative vegetation data recorded in a standardized sampling design. The data support the division of grasslands into the main phytogeographic units of the region (Brazilian biome classification). Grasslands in these two regions also differ in terms of species dominance pattern (higher dominance in Pampa grasslands, likely also due to higher grazing levels) and in terms of conservation state (low presence of exotic species in highland grasslands). Our results are important for conservation policies, which can now consider the presence of different grassland types in different region, but more data will be necessary for a more detailed classification that considers different abiotic features in more detail.

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The expansion of land use for agriculture is among the main reasons for the reduction of natural grasslands around the world, and little is known about the recovery potential of original native grassland vegetation from seed banks. The aim of this study was to assess the seed bank potential of grassland areas with or without history of cultivation in southern Brazil. Specifically, we aimed at evaluating if agricultural use allowed for the persistence of species typical of natural grasslands in soil seed banks. We analyzed seed banks in two areas with a history of cultivation and in two natural grasslands. Samples were collected in spring and autumn in order to assess transient and persistent components, and were characterized by density, richness, presence of exotic species and relationship between seed bank and established vegetation. Both richness and density were high; we found a total of 114 species and a mean density of 61,796 seedlings/m 2 for all four areas in the spring sampling. In the natural grasslands, the dominant species of established vegetation were mostly absent from the soil seed bank. Our study indicates that the seed bank is of little relevance for the recovery of typical grassland vegetation after disturbance.

-Coastal grasslands are one of the most threatened types of grasslands in the southern Brazil. To evaluate if areas with diff erent landuse history diff er in current grassland species composition and structure, four areas were selected according to current management: Entisols areas used for extensive livestock breeding (GR1 and GR2 sites); Alfi sols areas used for rice production with fallow periods (GRC), and for rotation with soybean (GSB). In each area, soil and grassland vegetation were characterized. We verifi ed that GR1, GSB, GRC and GR2 sites followed a decreasing order of species richness. Despite the higher richness found in GSB and GRC sites, few native perennial species with high coverage were recorded, due to dominating exotics and annuals. In contrast, grasslands used for pasture presented the typical vegetation features. For eff ective conservation eff orts, we highlight the importance to keep grasslands on both soil types.Keywords: crop rotation, Pampa, sandy soils RESUMO -O uso da terra e a conservação da biodiversidade: um estudo de caso nos campos na Planície Costeira, Rio Grande do Sul. Os campos da região costeira estão entre os mais ameaçados do sul do Brasil. Para avaliar como áreas com diferentes históricos de uso variam quanto à composição e estrutura da vegetação, selecionamos quatro áreas: duas com Neossolos utilizadas para pecuária (áreas GR1 e GR2); e as demais com Planossolos em intervalo de pousio após cultivo de arroz (área GRC) e rotação soja/pastagem (área GSB). Em cada área, solo e vegetação campestre foram caracterizados. As áreas GR1, GSB, GRC e GR2 seguiram um padrão decrescente de riqueza. Apesar da alta riqueza em GSB e GRC, poucas espécies nativas perenes com alta cobertura foram registradas, havendo predomínio de exóticas e anuais. Já campos utilizados para pastejo mantiveram características típicas da região. Para assegurar a conservação desses campos é necessária a manutenção de áreas campestres sobre os dois tipos de solos.Palavras-chave: neossolos, Pampa, rotação de culturas