Flavio Antonio Maës dos Santos

Fenologia da copaíba (Copaifera langsdorffii Desf. -- Leguminosae, Caesalpinioideae) em uma floresta semidecídua no sudeste do Brasil

Plant phenology is concerned with the timing of recurring events, and is poorly known for tropical forest species, although this ecosystem has the greatest diversity of phenological patterns. A phenological study was carried out from February/1991 to April/1993. Thirty six trees were systematically observed biweekly for changes on leaf fall, leaf flushing, flowering and fruiting. Leaf fall and flushing were synchronized phases. These events always occurred at the end of dry season (leaf fall) and start of rainy season (leaf flushing) being clearly related with precipitation. The flowering occurred in the rainy season, and fruiting during the dry season. Fruiting did not show an annual cycle, but years which massive fruiting being followed by non productive years. Other non climatic factors, like seed dispersers and seed predators were also likely to affect fruiting.

Scaling of stem and crown in eight Cecropia (Cecropiaceae) species of Brazil

The scaling of stem and crown was studied in eight Cecropia species in Amazonian and southeastern forests of Brazil. The Amazonian species, C. concolor, C. palmata, C. purpurascens, C. sciadophylla, and C. ulei were studied in Manaus, Amazonas, Brazil. The southeastern species, C. glaziovii, C. hololeuca, and C. pachystachya were studied in Linhares, Espírito Santo, Brazil. Measures of diameter, height, number of branches, number of leaves, and total leaf area were log transformed and regressed on height. Three models of mechanical designs of trees, elastic, constant stress, and geometric similarity, were tested for Cecropia. None of the models can totally describe Cecropia, but geometric similarity was a close approximation. Most of the species did not vary in diameter-height relationships between unbranched and branched individuals. Safety factors diminished with height in most species studied. The crown-height relationships were similar for all species. Numbers of branches and leaves showed some variation among species and are related to height of first branching. Total leaf area had a constant allometric relationship among species, although regression intercepts differed according to species leaf areas. The scaling relationships of stem and crown in Cecropia varied with adult size of the studied species.

Tree allometry and crown shape of four tree species in Atlantic rain forest, south-east Brazil

The allometry of crown shape and trunk diameter with tree height were analysed for four tree species in a tropical lowland rain forest, southeast Brazil. The dimensional relationships of a subcanopy species (Garcinia gardneriana) were contrasted with those of two canopy (Chrysophyllum flexuosum and Swartzia simplex) and one emergent species (Sloanea guianensis). For all trees 1 cm dbh, we recorded dbh, total height, branching height, crown area, crown width and crown length. Observed allometric relationships indicated interspecific variation in trunk diameter and crown shape with height. All species conformed to the elastic similarity model, except the emergent one that showed thicker trunks and a scaling exponent conforming to the constant stress model. The general allometric function used to describe the overall relationship (all sizes combined) did not specify exceptional variation in crown shape between species of contrasting adult stature (emergent vs. subcanopy species). However, when allometric relationships through ontogeny were considered, different strategies of growth, maintenance and expansion of crown became evident. Crown shapes were much more variable in canopy and emergent species than in the subcanopy one, suggesting that larger- statured species might be more flexible inthe relative allocationof en ergy to height, diameter, and crown growth than smaller-statured ones. Notwithstanding, it is suggested that it is not possible adequately to predict allometric relationships only by adult stature/canopy position. Allometric variation may be also related to size-dependent changes in demographic traits and/or different responses to light availability among tree species.

Stocks of carbon and nitrogen and partitioning between above- and belowground pools in the Brazilian coastal Atlantic Forest elevation range

We estimated carbon and nitrogen stocks in aboveground biomass (AGB) and belowground biomass (BGB) along an elevation range in forest sites located on the steep slopes of the Serra do Mar on the north coast of the State of São Paulo, southeast Brazil. In elevations of 100 m (lowland), 400 m (submontane), and 1000 m (montane) four 1-ha plots were established, and above- (live and dead) and belowground (live and dead) biomass were determined. Carbon and nitrogen concentrations in each compartment were determined and used to convert biomass into carbon and nitrogen stocks. The carbon aboveground stock (CAGB) varied along the elevation range from approximately 110 to 150 Mg·ha−1, and nitrogen aboveground stock (NAGB), varied from approximately 1.0 to 1.9 Mg·ha−1. The carbon belowground stock (CBGB) and the nitrogen belowground stock (NBGB) were significantly higher than the AGB and varied along the elevation range from approximately 200–300 Mg·ha−1, and from 14 to 20 Mg·ha−1, respectively. Finally, the total carbon stock (CTOTAL) varied from approximately 320 to 460 Mg·ha−1, and the nitrogen total stock (NTOTAL) from approximately 15 to 22 Mg·ha−1. Most of the carbon and nitrogen stocks were found belowground and not aboveground as normally found in lowland tropical forests. The above- and belowground stocks, and consequently, the total stocks of carbon and nitrogen increased significantly with elevation. As the soil and air temperature also decreased significantly with elevation, we found a significantly inverse relationship between carbon and nitrogen stocks and temperature. Using this inverse relationship, we made a first approach estimate that an increase of 1°C in soil temperature would decrease the carbon and nitrogen stocks in approximately 17 Mg·ha−1 and 1 Mg·ha−1 of carbon and nitrogen, respectively.

Florestas de restinga e de terras baixas na planície costeira do sudeste do Brasil: vegetação e heterogeneidade ambiental

It was evaluated the floristic similarity between two Atlantic Rainforest physiognomies in Brazilian coast area, herein called Restinga and Lowland forests. The hypothesis was that, due the differences in geomorphologic processes, these forests would differ on soil physical and chemical properties, floristic composition, live above-ground biomass and litterfall production. It was sampled 1 ha (100 × 100 m) for each site located in Ubatuba, Sao Paulo state, SE Brazil. Within each hectare it was recorded trees with DBH > 4.8 cm in all 10 × 10 m contiguous plots, and collected soil and litterfall samples. The cluster and ordination analyses indicated the two communities as distinct groups considering soil and floristic composition, agreeing with the initial hypothesis. Species diversity was higher (p 0.05) between the two forests. This apparent paradox could be explained assuming that, since different species establish themselves in the Restinga or Lowland forests and find a favorable spectrum of conditions and resources, they would tend to persist and to develop in that place; even so the edaphic conditions differ between the Restinga and Lowland forests, each species could respond in a particular way to these variations, and then both forests could reach similar values of biomass and litterfall production. It is probable that the environmental filter conditioned by soils has being important for the strong floristic segregation between these two forests.

Ethnobotany, Traditional Knowledge, and Diachronic Changes in Non–Timber Forest Products Management: A Case Study of Himatanthus drasticus (Apocynaceae) in the Brazilian Savanna1

Ethnobotany, Traditional Knowledge, and Diachronic Changes in Non–Timber Forest Products Management: A Case Study ofHimatanthus drasticus(Apocynaceae) in the Brazilian Savanna. The analysis of factors and processes that affect the traditional knowledge and the management practices deriving from it are essential for devising conservation strategies for non–timber forest products. The purpose of this study is to assess the traditional knowledge and analyze diachronic changes in management systems for non–timber forest products in a case study of an intensely exploited species from the Brazilian savanna, Himatanthus drasticus, commonly known as “janaguba.” Janaguba produces a latex of commercial value, widely used in popular medicine in Brazil. Recent pharmacological evidence of its medicinal properties has increased harvesting pressure on this resource. For this reason, we carried out an ethnobotanical characterization of the management systems used to harvest janaguba latex and of the traditional ecological knowledge associated with such practices. Three management systems were identified in latex harvesting, which may have varying ecological impacts on janaguba populations, depending on the amount of bark removed and the time interval between harvestings. Among the factors that can influence changes in the management systems over time are market pressure and growing demand for the product, loss of traditional knowledge, the system of land tenure, and the biological characteristics of the species, especially its high biomass regeneration capacity.Etnobotânica, conhecimento tradicional, e mudanças diacrônicas no manejo de produtos florestais não–madeireiros: Um estudo de caso deHimatanthus drasticus(Apocynaceae) na savana Brasileira. A análise dos fatores e processos que afetam o conhecimento tradicional, bem como as práticas de manejo derivadas dele, é fundamental para a elaboração de estratégias de conservação de produtos florestais não–madeireiros. O objetivo desse trabalho é acessar o conhecimento tradicional e avaliar as mudanças diacrônicas nos sistemas de manejo de produtos–florestais não–madeireiros, a partir de um estudo de caso com uma espécie altamente explorada na savana brasileira. O látex de janaguba (Himatanthus drasticus) é comercializado devido à sua ampla utilização na medicina popular no Brasil. A recente comprovação farmacológica das propriedades medicinais da espécie vem aumentando a pressão de coleta deste recurso. Foi realizada uma caracterização etnobotânica dos sistemas de manejo de látex de janaguba, bem como do conhecimento ecológico tradicional associado a estas práticas. Foi possível identificar três sistemas de manejo empregados para coleta do látex de janaguba, os quais podem ter impactos ecológicos distintos sobre as populações exploradas, uma vez que se diferenciam em função da quantidade de casca retirada e intervalos entre explorações. Entre os fatores que podem influenciar a mudança dos sistemas de manejo ao longo do tempo encontram-se a influência do mercado e crescente demanda pelo produto, a perda do conhecimento tradicional, a posse da terra e as características biológicas da espécie, especialmente sua alta capacidade de regeneração de biomassa.

Demography, phenology and sex of Calophyllum brasiliense (Clusiaceae) trees in the Atlantic forest

Further studies on growth and reproduction of many tree species are needed to know the regeneration patterns of tropical forests (Clark & Clark 1987, Heideman 1989). Thus, the need for studies on the c. 3% of Atlantic forest that remains in Brazil is acute, particularly in the rarely studied swamp habitats (Scarano et al. 1997). We studied the canopy tree species Calophyllum brasiliense Camb. (Clusiaceae) in flooded and unflooded habitats of a coastal lowland rain forest, in order to describe demography, sexual expression, phenology and flower and fruit production. We report the differences of such traits among three contiguous habitats found in the lowlands - unflooded forest, freshwater-flooded forest and mangrove.

Alometria de plântulas e jovens de espécies arbóreas: copa x altura

Most of the morphological and developmental characteristics of different parts of a plant may vary in function of the species architecture, microenvironment and degree of ecological restriction where its has begun it growth. This study aimed to analyze the allometric relation between height and the largest horizontal crown axis and, for a community of tree seedlings and saplings up to 1 m in height in the Reserva Estadual do Morro Grande (23o35’S - 23o50’S; 46o45’W - 47o15’W), situated in Sao Paulo’s Atlantic Plateau, SE Brazil. We sampled 600 individuals in 34 1m2 plots distant 2.5 m from each other along six transects, 100 individuals per transect. For each individual we measured their height and largest crown axis. We adjusted different regression models (linear, exponential, power, polynomial and logarithmic) to the data. The best fit was for the power model (r2 = 0.640, p<0.001). The fact that juveniles from different species adjust to the same allometric model suggests that ecological factors could have an important restrictive role in the allometry of seedlings and saplings of tree species.

Allometry of a neotropical palm, Euterpe edulis Mart.

Neste trabalho foram analisadas as relacoes entre o diâmetro e a altura de uma palmeira Neotropical (Euterpe edulis) comum na Floresta Atlântica do SE do Brasil. As relacoes observadas entre a altura e o diâmetro ao longo do estipe (diâmetro ao nivel do solo (DAS), e diâmetro ao nivel do peito (DAP) foram comparadas a tres modelos teoricos de estabilidade mecânica: similaridade elastica, similaridade de estresse e similaridade geometrica. As inclinacoes das regressoes altura-diâmetro nao se ajustaram a nenhum dos modelos de estabilidade mecânica. Diferencas significativas na alometria do estipe foram encontradas comparando-se as relacoes altura-DAS com altura-DAP, sugerindo maior incremento em DAP com a altura. A relacao entre o fator de seguranca do diâmetro contra quebra e a altura mostrou que tanto o DAS como o DAP encontram-se acima do limite teorico de quebra de McMahon para arvores, mas alguns individuos aproximam-se deste limite em relacao ao DAP. Apesar de apresentarem padrao similar de decrescimo do fator de seguranca com a altura, as diferencas encontradas para o fator de seguranca ao longo do estipe - maior fator de seguranca para o DAS quando comparado com o DAP - indicam que o risco de quebra em palmeiras depende do tamanho e varia ao longo do estipe. As relacoes alometricas distintas ao longo do estipe obtidas para Euterpe edulis podem estar refletindo possiveis diferencas na forma do estipe e nas estrategias de crescimento.

Estrutura de estádios ontogenéticos em população nativa da palmeira Syagrus romanzoffiana (Cham.) Glassman (Arecaceae)

Syagrus romanzoffiana is ecologically and economically important, including the production of good-quality hearts of palm. Aiming to describe this plants basic life cycle, we studied a natural population in the swamp forest at the Santa Genebra Reserve, Campinas municipality, Sao Paulo state. Observations and measurements were made, and repeated after 400 ± 3 days, in 100 randomly located plots (5×5 m) and sub-plots (2×2 m), in an area of 1 ha. Six ontogenetic stages were recognized: seedling (narrow entire leaf), juvenile phase 1 (entire leaf, width > 2 cm), juvenile phase 2 (segmented leaf), immature (segmented leaf, aerial stem), virgin (aerial stem, cauligenous roots), and reproductive (cauligenous roots and periodic presence of reproductive structures). Since the moment of trophic independence could not be determined in the field, leaf characteristics were used to identify seedlings. Seedlings live for a long time in the low light of the understory. Even though significant differences could be observed, size and leaf production overlapped among different stages. Remote germination, used to explain the widespread occurrence of the species even in dry regions, and cauligenous roots that improve fixation and nutrition previous to reproduction in swamp forests, are morphological structures and properties acquired or lost in each stage that may represent adaptive advantages under different circumstances during ontogeny of S. romanzoffiana.