Estrutura e composi？？o de um trecho de Mata Atlantica no Parque Estadual das Fontes do Ipiranga, S？o Paulo, SP, Brasil

structure and composition of a patch of atlantic forest in s？o paulo plateau was studied in an area of 5 ha in 30 circular plots of 50 m2 (3.99 m radius) at 5, 15 and 45 m from the edge, distributed in 10 plots by distance. woody plants over 2.5 m in height were sampled. myrtaceae and lauraceae with 12 species and rubiaceae with 11, were the richest families in species number. the floristic diversity (h') of the sampled area was 4.06. the main botanical families of the s？o paulo plateau are represented in the sampled area and this site has an high diversity and species richness compared to other forest parts of the great s？o paulo city, although the high density of some pioneer species such as alchornea sidifolia müll. arg. can show forest tracts disturbed by fragmentation. management actions for conservation are suggested.