Relações histórico - florísticas, fitossociologia e aspectos ecológicos do Alecrim (Holocalyx balansae Mich.) em floresta primária, na região de Formigueiro – RS

The forests of the Depressão Central in the State of Rio Grande do Sul, are in an advanced process of fragmentation, as a consequence of the expansion of the agriculture area. These fragments are in different degrees of conservation due to selective wood extraction and the action the cattle reising. The lack of studies about floristic composition, structure, reproductive strategies of arboreal species and the fragmentation effects on ecosystems, turn impratical any practice that garantee the conservation of forest genetic resourses in situ. This work relies on results obtained in a fragment untouched in Formigueiro county. Floristic data presented here are inserted in the dynamic context of the southern Brazil vegetation, under the influence of climatic changes in the Quaternary, identifing the original flora and the recent features of these forests. The structural analysis detected the occurence of alecrim (Holocalyx balansae Mich), a specie that in spite of being rare in the Depressão Central, presented high density in the study area. Based on the results obtained in loco, we conclude that alecrim is characterisis itself as a climax specie and, therefore, vulnerable to fragmentation. These informations, although incomplete, is of great importance in the conservation of produtive characteristics of forest. The lack of it, turns impratical the permanence of these fragments in rural properties.