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1.
Proc Natl Acad Sci U S A ; 114(40): 10695-10700, 2017 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-28923966

RESUMO

Recent debates on the number of plant species in the vast lowland rain forests of the Amazon have been based largely on model estimates, neglecting published checklists based on verified voucher data. Here we collate taxonomically verified checklists to present a list of seed plant species from lowland Amazon rain forests. Our list comprises 14,003 species, of which 6,727 are trees. These figures are similar to estimates derived from nonparametric ecological models, but they contrast strongly with predictions of much higher tree diversity derived from parametric models. Based on the known proportion of tree species in neotropical lowland rain forest communities as measured in complete plot censuses, and on overall estimates of seed plant diversity in Brazil and in the neotropics in general, it is more likely that tree diversity in the Amazon is closer to the lower estimates derived from nonparametric models. Much remains unknown about Amazonian plant diversity, but this taxonomically verified dataset provides a valid starting point for macroecological and evolutionary studies aimed at understanding the origin, evolution, and ecology of the exceptional biodiversity of Amazonian forests.


Assuntos
Biodiversidade , Bases de Dados Factuais , Plantas/classificação , Floresta Úmida , Brasil
2.
Am J Bot ; 103(6): 1089-102, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27329943

RESUMO

PREMISE OF THE STUDY: The complex geological and climatic history of the Neotropics has had major implications on the diversification of plant lineages. Chrysobalanaceae is a pantropical family of trees and shrubs with 75% of its 531 species found in the Neotropics, and a time-calibrated phylogeny of this family should shed light on the tempo of diversification in the Neotropical flora. Previously published phylogenetic hypotheses of this family were poorly supported, and its biogeography remains unclear. METHODS: We assembled the complete plastid genome of 51 Chrysobalanaceae species, and increased taxon sampling by Sanger-sequencing of five plastid regions for an additional 88 species. We generated a time-calibrated tree including all 139 Chrsyobalanaceae species and 23 outgroups. We then conducted an ancestral area reconstruction analysis and estimated diversification rates in the family. KEY RESULTS: The tree generated with the plastid genome alignment was almost fully resolved. It supports the polyphyly of Licania and Hirtella. The family has diversified starting around the Eocene-Oligocene transition. An ancestral area reconstruction confirms a Paleotropical origin for Chrysobalanaceae with several transoceanic dispersal events. The main Neotropical clade likely resulted from a single migration event from Africa around 28 mya ago, which subsequently underwent rapid diversification. CONCLUSIONS: Given the diverse ecologies exhibited by extant species, we hypothesize that the rapid diversification of Chrysobalanaceae following the colonization of the Neotropics was triggered by habitat specialization during the complex geological and paleoclimatic history of the Neotropics.


Assuntos
Chrysobalanaceae/classificação , Chrysobalanaceae/genética , Genomas de Plastídeos , Filogeografia , Sequência de Bases , Extinção Biológica , Especiação Genética , Variação Genética , Filogenia , Análise de Sequência de DNA , Especificidade da Espécie , Fatores de Tempo
3.
Proc Natl Acad Sci U S A ; 107(51): 22169-71, 2010 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-21135225

RESUMO

Despite the importance of species discovery, the processes including collecting, recognizing, and describing new species are poorly understood. Data are presented for flowering plants, measuring quantitatively the lag between the date a specimen of a new species was collected for the first time and when it was subsequently described and published. The data from our sample of new species published between 1970 and 2010 show that only 16% were described within five years of being collected for the first time. The description of the remaining 84% involved much older specimens, with nearly one-quarter of new species descriptions involving specimens >50 y old. Extrapolation of these results suggest that, of the estimated 70,000 species still to be described, more than half already have been collected and are stored in herbaria. Effort, funding, and research focus should, therefore, be directed as much to examining extant herbarium material as collecting new material in the field.


Assuntos
Plantas/classificação , Manejo de Espécimes , Especificidade da Espécie
4.
PhytoKeys ; (42): 1-10, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25383007

RESUMO

Recent collections received for identification contain three conspicuous new species for the mid altitude forests of Amazonian Peru. Licaniapalcazuensis, Licaniaapiknae and Licaniamonteagudensis are described as new and their relationship to other species is discussed. A key is provided for all the species of LicaniasubgenusLicaniasectionLicania known to occur in Peru.

5.
PhytoKeys ; (26): 71-4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24194670

RESUMO

A new mid altitude species of the predominantly lowland genus Licania, Licania condoriensis from Ecuador is described and illustrated.

6.
PhytoKeys ; (13): 1-4, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22787422

RESUMO

A new species of Roupala, Roupala gertii from the endangered Atlantic coastal forests of Brazil is described and illustrated.

7.
Philos Trans A Math Phys Eng Sci ; 360(1797): 1777-85, 2002 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12460497

RESUMO

Since deforestation is one of the sources of carbon dioxide increase in the atmosphere, any measures that prevent or reduce the amount of forest removal are beneficial to the environment and to conservation of biodiversity. In recent years, there has been considerable research on the value of standing forests and many researchers have promoted the management of tropical forests as the best type of land use. On the other hand, the enormous diversity is a serious obstacle to management and use of tropical rainforest. A single hectare of forest can have up to 306 species of trees of 10 cm diameter or more. Here we present a brief review of some of the research and programmes that have tried to promote the use and conservation of tropical forest without clear felling. The sustainable use of the standing forest has usually been promoted as a means of species conservation; however, it is also a way to maintain the carbon fixed in the ecosystem. Here we review some of the pros and cons of extraction of non-timber forest products.


Assuntos
Carbono/economia , Conservação dos Recursos Naturais/economia , Agricultura Florestal/economia , Variação Genética , Árvores/classificação , Clima Tropical , Carbono/análise , Ecossistema , Geografia , Especificidade da Espécie , Árvores/crescimento & desenvolvimento
8.
Philos Trans A Math Phys Eng Sci ; 360(1797): 1593-605, 2002 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12460486

RESUMO

The global carbon cycle is significantly influenced by changes in the use and management of forests and agriculture. Humans have the potential through changes in land use and management to alter the magnitude of forest-carbon stocks and the direction of forest-carbon fluxes. However, controversy over the use of biological means to absorb or reduce emissions of CO(2) (often referred to as carbon 'sinks') has arisen in the context of the Kyoto Protocol. The controversy is based primarily on two arguments: sinks may allow developed nations to delay or avoid actions to reduce fossil fuel emissions, and the technical and operational difficulties are too threatening to the successful implementation of land use and forestry projects for providing carbon offsets. Here we discuss the importance of including carbon sinks in efforts to address global warming and the consequent additional social, environmental and economic benefits to host countries. Activities in tropical forest lands provide the lowest cost methods both of reducing emissions and reducing atmospheric concentrations of greenhouse gases. We conclude that the various objections raised as to the inclusion of carbon sinks to ameliorate climate change can be addressed by existing techniques and technology. Carbon sinks provide a practical available method of achieving meaningful reductions in atmospheric concentrations of carbon dioxide while at the same time contribute to national sustainable development goals.


Assuntos
Poluentes Atmosféricos/normas , Carbono/metabolismo , Poluição Ambiental/prevenção & controle , Agricultura Florestal , Efeito Estufa , Cooperação Internacional , Dióxido de Carbono/metabolismo , Conservação dos Recursos Naturais/legislação & jurisprudência , Ecossistema , Geografia , Árvores , Nações Unidas
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