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Summary The differences in plant community structure and soil properties between streamside and upland topographical sites were analysed in an area of montane semideciduous forest on the margins of the Camargos Reservoir, southeastern Brazil. The studied forest patch lies at the headwaters of two narrow streams and is surrounded by montane grasslands. The plant community was surveyed by one 30 × 150 m and one 30 × 165 m transects, both made up of 15 × 15 m contiguous quadrats. The first transect extended along one of the streams while the other linked the two streams by traversing the interfluve. Soil samples were collected from all quadrats and their texture and chemical properties were analysed in the laboratory. The streamside soils were tropical Podzolic Soils, characterised by clay depletion of the top layer with its accumulation in the deeper horizons. The upland soils were Cambisols, a 'maturing' soil type with no clear zonation. A canonical correspondence analysis indicated that the species' abundance distribution was significantly correlated with the two topographical sites as well as with some soil properties. The most abundant species appeared to vary from fairly exclusive streamside or upland preferentials to broadly indifferent for the two habitats. A tentative ecological classification of the 69 most abundant species according to their preference for streamside or upland habitat and to their growth strategy in the forest dynamics, is presented. An overall analysis of this classification along with the differences in soil properties between the two topographic sites gives evidence that the forest probably expanded from the two valley bottoms towards the upland sector occupying sites that were previously covered with montane grasslands.

Realizou-se o levantamento florístico e fitossociológico da comunidade arbórea de um fragmento de Floresta Estacionai Semidecidual Sub-Montana localizado às margens do reservatório da usina hidrelétrica Dona Rita, situado na Fazenda Camarinha, em Itambé do Mato Dentro, MG, na bacia do rio Doce (19º26'S, 43º 14' W, altitude entre 610 e 630m). Todos os indivíduos com diâmetro do caule à altura do solo > 5,0cm (exceto lianas) encontrados em 35 parcelas de 15xl5m (0,78ha) foram identificados, medidos e tiveram sua altura estimada (também foram coletados indivíduos que se apresentavam com estruturas reprodutivas, fora das parcelas). Foram estimados para cada espécie os seguintes parâmetros: densidade por área, freqüência absoluta, dominância absoluta e índice de valor de importância (IVI). Também foram calculados o índice de diversidade de Shannon e a equabilidade correspondente, o índice de similaridade de Jaccard e as distâncias euclidianas quadradas entre esta floresta e outras do alto e médio Rio Grande, baixo Paranaíba e alto São Francisco. Nas parcelas foram amostrados 2.430 indivíduos. Identificou-se 216 espécies (15 fora das parcelas) pertencentes a 50 famílias e 144 gêneros. Destacam-se pelo IVI as famílias Euphorbiaceae, Myrtaceae e Caesalpiniaceae e as espécies Apuleia leiocarpa, Pera glabrata, Licania hypoleuca e Mabeafistulifera. Comparada com algumas florestas ciliares do Estado, a floresta de Itambé do Mato Dentro se assemelha mais com a do alto Rio Grande (ambas localizadas em regiões sob influência da Mata Atlântica), muito embora as espécies mais importantes não sejam as mesmas. Em termos pedológicos a floresta de Itambé apresenta os solos mais intemperizados, lixiviados e profundos, apesar de seu relevo íngreme, devido ao material constitutivo dos mesmos ter sofrido intenso processo de alteração anterior ao atual ciclo pedogênico. A floristic and phytosociological survey of the tree commnunity was carried out in a fragment of sub-montane semideciduous forest located on the margin of the Dona Rita Hydroelectric Reservoir, municipality of Itambé do Mato Dentro, State of Minas Gerais, south-eastern Brazil (19º26'S, 43º14'W, 610-630m of altitude). All individuals with a stem diameter at the base, of dbt > 5cm (lianas excepted) found in thirty five 15x15m quadrats, were identified, measured (dbt) and had their height estimated (individuals found outside quadrats with reproductive structure were also collected). The following phytosociological parameters were calculated for all species: density per area, absolute frequency, absolute dominance calculated from the basal area, and importance value. The Shannon diversity index and the corresponding evenness were calculated. Jaccard's similarity indices and euclidian distances were also calculated among the studied forest and other forests surveyed in the following regions of Minas Gerais State: Upper and Mid Rio Grande, Lower Rio Paranaiba and Upper Rio São Francisco. A total of 2,430 individuals were recorded in the sample area. These belonged to 50 families, 144 genera and 216 species. The following families produced the highest importance values: Euphorbiaceae, Myrtaceae and Caesalpiniaceae. The most important species were Apuleia leiocarpa, Pera glab rata, Licania hypoleuca, and Mabeafistulifera. A comparison with the other areas indicated that the forest of Itambé do Mato Dentro is more similar to those of the Upper Rio Grande which are all under a stronger floristic influence of the Atlantic Forest, although the most important species are not the same. The soils of the area are deeper, highly weathered and leached, despite the strongly sloping topography because they had gone through an intense process of alteration prior to the present pedogenetic cycle.

Realizou-se o levantamento das espécies com diâmetro ao nível do solo > ou = 5,0 cm na mata da Fazenda dos Botelhos, em Bom Sucesso, localizada às margens do Rio Grande, no Sul de Minas Gerais, com o objetivo de reconhecer espécies nativas a serem utilizadas na revegetação das margens de rios e represas da região. Identificaram-se 245 espécies pertencentes à 65 famílias botânicas. São apresentadas comparações florísticas com matas do estado de São Paulo. A floristic survey was carried out in a riparian forest of the Rio Grande in Bom Sucesso, Minas Gerais, Brazil, considering the species of trees and shrubs with diameter at the base of the stem > or = 5 cm. The purpose was to produce a list of indigenous species for potential use in environmental rehabilitation programs that have bee carried out on the margins of rivers and dams of this region. A list is provided with 245 species of 65 botanic families. Floristic comparisons are made with florests surveyed in the State of São Paulo.

A floristic survey was carried out in an 9.450m2 fragment of riparian forest on the margin of the hydroelectric reservoir of Camargos, Itutinga, state of Minas Gerais, SE Brazil. All individuals with minimum diameter at the base of stem 5cm were surveyed in the sampled area forest. A list is provided with 253 species of trees and shrubs belonging to 66 botanic families. Floristic similarity indices were calculated in comparisons with other floristic surveys of forest in the states of Sao Paulo and Minas Gerais.