12 documents found, page 1 of 2

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...

Flood pulse and spatial dynamics of mercury in sediments in Puruzinho lake, Bra...

The study was conducted in Puruzinho lake (Humaitá, AM) considering seasonal periods of rainy and dry in way to elucidate the flood pulse importance in the deposition, remobilization and distributions of mercury and organic matter in bottom sediments in the Madeira River Basin (Brazilian Amazon). Bottom sediments and soils samples were analyzed for total mercury and organic matter. Mercury concentrations obtain...

Taking the pulse of Earth's tropical forests using networks of highly distribut...

Made available in DSpace on 2021-06-25T11:16:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01; Agence Nationale Des Parcs Nationaux; Centre for International Forestry Research; Departamento Administrativo de Ciencia, Tecnología e Innovación (COLCIENCIAS); David and Lucile Packard Foundation; European Space Agency; Leverhulme Trust; Gordon and Betty Moore Foundation; Fundação de Amparo à Pesquisa ...

Biased-corrected richness estimates for the Amazonian tree flora

Made available in DSpace on 2020-12-12T01:28:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-12-01; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); 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 exten...

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...

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,...

The Brazilian Program for Biodiversity Research (PPBio) Information System

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 ...

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 ...

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 ...