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Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain underst...

Impactos da disposição de resíduos sólidos urbanos no solo e água nos município...

A disposição final inadequada dos resíduos sólidos é um problema comum na maioria das cidades brasileiras, reflete a precariedade do sistema de saneamento básico, em especial dos serviços de limpeza urbana e manejo de resíduos sólidos, gerando grandes impactos socioeconômicos e ambientais no país. A região norte do Brasil apresenta os piores dados de cobertura de saneamento básico e disposição correta de resídu...

Rarity of monodominance in hyperdiverse Amazonian forests

Made available in DSpace on 2020-12-12T01:40:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-12-01; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Tropical forests are known for their high diversity. Yet, forest patches do occur in the tropics where a single tree species is dominant. Such “monodominant” forests are known from all of the main tropical regions. For Amazonia, we sam...

Estimativa de biomassa lenhosa acima do solo ao longo do gradiente inundável de...

Biased-corrected richness estimates for the Amazonian tree flora

Amazonian forests are extraordinarily diverse, but the estimated species richness is very much debated. Here, we apply an ensemble of parametric estimators and a novel technique that includes conspecific spatial aggregation to an extended database of forest plots with up-to-date taxonomy. We show that the species abundance distribution of Amazonia is best approximated by a logseries with aggregated individuals,...

Estimating the global conservation status of more than 15,000 Amazonian tree sp...

Estimates of extinction risk for Amazonian plant and animal species are rare and not often incorporated into land-use policy and conservation planning. We overlay spatial distribution models with historical and projected deforestation to show that at least 36% and up to 57% of all Amazonian tree species are likely to qualify as globally threatened under International Union for Conservation of Nature (IUCN) Red ...

Composition, structure and floristic diversity in dense rain forest in the east...

This study aims to evaluate the phytosociology and floristic composition of tree species in the eastern Amazon, at the Iratapuru River Sustainable Development Reserve (RDS), State of Amapá. Fouteen quarters with dimensions of 100 m x 100 m were randomly inventoried, and 50 sub-plots of 10 m x 20 m were established. In each sub-plot all living individuals were sampled, being taken from the height data and DAP (b...

Species Distribution Modelling: Contrasting presence-only models with plot abun...

Species distribution models (SDMs) are widely used in ecology and conservation. Presence-only SDMs such as MaxEnt frequently use natural history collections (NHCs) as occurrence data, given their huge numbers and accessibility. NHCs are often spatially biased which may generate inaccuracies in SDMs. Here, we test how the distribution of NHCs and MaxEnt predictions relates to a spatial abundance model, based on ...

Floristic diversity of secondary forest in the eastern Amazon, state of Amapá

The increasing importance of secondary forests all over the world alerts us to the urgent need to understand the biophysical and social underlying factors that affect its regeneration after the abandonment of agricultural practices and natural disturbances. In the state of Amapá, studies related to the structure of secondary forests are still scarce. Therefore, this article aims to characterize the floristic co...

Rarity of monodominance in hyperdiverse Amazonian forests

Tropical forests are known for their high diversity. Yet, forest patches do occur in the tropics where a single tree species is dominant. Such “monodominant” forests are known from all of the main tropical regions. For Amazonia, we sampled the occurrence of monodominance in a massive, basin-wide database of forest-inventory plots from the Amazon Tree Diversity Network (ATDN). Utilizing a simple defining metric ...