Phenological studies were carried out in gallery and montane forests along the Lençóis River in the Chapada Diamantina mountains, state of Bahia, Brazil, between January 1993 and March 1998. Leaf flush, leaf fall, flowering, and fruiting were followed in 54 tree species (N= 243 trees tagged along trails following the river margin and the valley sides). Both gallery and montane forests exhibited a moderate peak in leaf fall during die dry season (August–October), as well as increased leaf flushing in the rainy season (December–April). Three basic modes of leafing activity were noted, although most trees in the gallery forest and in the montane forest were evergreen (82.3 and 57.8% relative frequency, respectively). In both forest types, flowering and fruiting modes were annual, with peaks of activity during the rainy season. The predominantly evergreen mode of leaf fall and leaf flush found in this study was most similar to that seen in tropical wet forests, while the flowering and fruiting modes were more similar to that of dry forests. RESUMES Foi desenvolvido um estudo fenológico em mata ciliar e mata de encosta adjacentes ao rio Lençóis, Chapada Diamantina, Bahia, Brasil entre Janeiro de 1993 a março de 1998 em 54 espécies de árvores, atentando‐se para as fenofases queda e brotamento de folhas, floração e frutificação. Foram acompanhados 243 individuos marcados ao longo de trilhas seguindo as margens do rio e na encosta. Em ambas as matas, verificou‐se um pico moderado de queda foliar durante a estação seca (agosto‐outubro) e maior brotamento durante a estação chuvosa (dezembro‐abril). Foram reconhecidos três padrões de queda e brotamento foliar, sendo os padrões perenifólios predominantes tanto na mata ciliar quanto na mata de encosta (82.3 e 57.8% Freqüência Relativa, respectivamente). Em ambas as matas, os padrões de floração e frutificação foram anuais, com picos de atividade durante a estação chuvosa. Os padrões de queda e produção foliar assemelharam‐se queles encontrados em matas umidas, sendo o perenifólio predominante; enquanto padrões de floração e frutificação são similares ao de matas secas.
Abstract:The Chapada Diamantina National Park (CDNP) was created in the midst of a densely populated area, and significant sections of the reserve are still undergoing processes of natural regeneration after intensive diamond mining activities were initiated in the mid-1800's. An up-to-date vegetation map was needed in order to indicate the types and distribution of regional vegetation assemblages in an easily interpretable manner and at an appropriate planning scale that could be easily consulted by decision makers and other interested groups at all levels of conservation (and development) planning. A vegetation map of the Chapada Diamantina National Park, and the areas immediately surrounding it, was prepared that: 1) delimits, describes, and maps the regional vegetation assemblages; 2) provides an indication of the degree of conservation of the mapped vegetation; 3) develops this information in a format that facilitates continued updating and revision as more information becomes available, enabling the monitoring of the evolution of the Park lands, and; 4) presents this information in a manner that can be easily interpreted and used for planning, management and conservation purposes. The resulting vegetation map revealed intensive anthropogenic disturbances in forested, savanna, and semi-arid areas subjected to intensive agricultural use outside of the Park boundaries. The National Park lands are generally well preserved but burning has replaced formerly extensive forest areas with open sedge meadows. In spite of intensive modification of the regional vegetation, two well preserved areas with high priority for conservation efforts beyond the National Park limits were identified and characterized. The vegetation mapping of the park itself can aid in the preparation of its management plan and in the reformulation of the existing boundaries of that reserve. Keywords: vegetation map, conservation planning, vegetation assemblages, forests. FUNCH, R.R. HARLEY, R.M. & FUNCH, L.S.Mapeamento e avaliação do estado de conservação da vegetação dentro e em torno do Parque Nacional da Chapada Diamantina, Nordeste do Brasil. Biota Neotrop. 9(2): http://www.biotaneotropica.org.br/v9n2/pt/abstract?article+bn00209022009.Resumo: O Parque Nacional da Chapada Diamantina foi criado numa região densamente ocupada e grandes áreas dentro desta reserva ainda estão em vias de recuperação natural em decorrência da mineração de diamantes que começou em 1844. Um mapa atualizado da vegetação regional elaborado de maneira que facilite sua interpretação é imprescindível para orientar administradores e outros grupos interessados na preservação e desenvolvimento da região. Um mapa da vegetação do Parque Nacional da Chapada Diamantina e as áreas no seu entorno foi preparado: 1) delimitando e descrevendo os vários tipos de vegetação regional; 2) fornecendo indicações do grau de conservação da vegetação; 3) apresentando estas informações num formato que facilite sua revisão e atualização; e 4) apresentando estas informações de maneira fácil de in...
This is apparently the first report for pollination biology and mating systems of Eriocaulaceae. Conversely to that stated by some authors, entomophily, mainly effected by species of Diptera but also by species of Coleoptera and Hymenoptera, is probably the only pollination system in these species. In spite of the monoecious inflorescences without overlap of the staminate and pistillate phases, geitonogamy may occur in S. mucugensis, as the species is self-compatible and different capitula in the same plant at different phases is common.
-(Reproductive phenology, pollination and seed dispersal syndromes on sandstone outcrop vegetation in the "Chapada Diamantina", northeastern Brazil: population and community analyses). Vegetation on rock outcrops in the "Chapada Diamantina" (soil islands) is often aggregated and surrounded by nude rock surfaces, thus creating natural units with well defined limits. The flowering and fruiting cycles of plants on 58 soil islands at altitudes between 1,100 and 1,140 meters above sea leavel were analyzed at Mãe Inácia Peak (12°27' S and 41°28' W) in the "Chapada Diamantina", Bahia, Brazil. The presence/ absence of flowering and fruiting species on each soil island, and their respective cover areas were analyzed at both the population and community levels, and the phenophases of flowering and fruiting were observed during 24 successive months. The analyses of pollination and seed dispersal syndromes indicated that animals are more important in pollination than in seed dispersal (which is predominantly by anemochory and autochory). The flowering and fruiting of plants with animal pollination syndromes were correlated with rainfall and temperature. The flowering season varied during the year according to the pollination syndrome involved: entomophily was predominant from summer through autumn, ornithophily was predominant during winter, and anemophily in the spring. The staggered timing of flowering and fruiting among different species provides a nearly continuous supply of resources for the local fauna.
The concept of growth rings is little discussed in the literature and their treatment remains somewhat confusing in terms of the diversity of structures described. This situation has a major impact on the study of growth rings in tropical species, in which variations and complexity are greater and accuracy of identification less good. The rigid conceptual delimitations used by dendrochronologists and wood anatomists of temperate regions cannot be applied to the study of growth rings in most tropical species, which has led to neglect of this subject. With the objective of discussing the concept of growth rings, the present study consists of a survey of anatomical, periodicity, causal and evolutionary aspects of the treatment of these structures as evidenced in previous studies, and the evaluation of their application and limitations to the development of this concept. Anatomical aspects arise through radial integrity, or the presence of early and late wood; the degree of distinction of the rings, which may vary from well to poorly defined; and tangential continuity, meaning that rings may form a complete circle in the transverse section of the trunk, or instead be tangentially discontinuous, lens-shaped or in wedges. In addition there are a diversity of anatomical markers which enable us to recognize growth rings. Regarding periodicity, the rings may be annual, infra-annual or supra-annual. Causal aspects include genetic, endogenous and environmental components. Evolutionary aspects continue to be insufficiently investigated, and although most comparative studies treat growth rings recognized by different markers as though they were a single character, it remains questionable whether they can be regarded as homologous or the result of homoplasy. We conclude that the elaboration of a robust but broad definition which can include all the variation observed in growth rings of tropical species is a complex task, which is only possible by overcoming the restrictions adopted by dendrochronologists and wood anatomists of temperate regions for whom growth rings are essentially annual, strongly demarcated, tangentially continuous and restricted to the most pronounced markers.
-(Phenological behavior of three species of Jatropha (Euphorbiaceae) in the semi-arid Caatinga region of Brazil). The vegetative and reproductive phenological behavior of Jatropha mollissima (Pohl) Baill., Jatropha mutabilis (Pohl) Baill. and Jatropha ribifolia (Pohl) Baill. were characterized and compared in an area of hyperxerophilous shrub-arboreal caatinga in northeastern Brazil from July 2005 to June 2007. The correlation between the phenophases and the abiotic variables (temperature, relative air humidity, precipitation and photoperiod), the capacity for water storage and the patterns of spatial distribution of these species were also investigated. All species showed high capacities for water storage, continuous and irregular phenological behaviors with flowers, fruits, leaf fall, and leaf budding absence during the coldest and wettest months. Only flowering in J. ribifolia demonstrated significant correlation with precipitation. All species presented aggregated distribution of their populations, which was favored by the ballistic autochory. These results indicated that the high capacity of these species for storing water facilitates the occurrence of phenological events even in the absence of rainfall.Key words -flowering, fruiting, Jatropha, phenology RESUMO -(Comportamento fenológico de três espécies de Jatropha (Euphorbiaceae) da Caatinga, semi-árido do Brasil). O comportamento fenológico vegetativo e reprodutivo de Jatropha mollissima (Pohl) Baill., Jatropha mutabilis (Pohl) Baill. e Jatropha ribifolia (Pohl) Baill. foi comparado em uma área de caatinga hiperxerófila arbustiva-arbórea do nordeste brasileiro, no período de julho de 2005 a junho de 2007. Adicionalmente, investigou-se a correlação entre as fenofases e as variáveis abióticas (temperatura, umidade relativa, precipitação e fotoperíodo), a capacidade de armazenamento de água e o padrão de distribuição espacial. Todas as espécies apresentaram alta capacidade de armazenamento de água e comportamento fenológico contínuo e irregular com ausência de flores, frutos, queda foliar e brotamento nos meses mais frios e úmidos do ano. Apenas a floração de J. ribifolia apresentou correlação significativa com a precipitação. As três espécies apresentaram populações com distribuição agregada, favorecida principalmente devido ao processo de dispersão de sementes por autocoria. Os resultados obtidos indicam que a alta capacidade de armazenamento de água pelas espécies garante a ocorrência dos eventos fenológicos mesmo na ausência de chuvas.Palavras-chave -fenologia, floração, frutificação, Jatropha 1.Parte da tese de doutorado do primeiro autor,
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