Abstract Detail


Reginato, Marcelo [1], Michelangeli, Fabian [2].

Bioregions of eastern Brazil based on vascular plant occurrence data.

The geographical division of the Earth into meaningful biodiversity units (e.g., biomes, areas of endemism, ecoregions or bioregions) is a necessary step for the study of biodiversity and its conservation. Eastern Brazil harbors a significant proportion of the Earth’s terrestrial biodiversity in a geographically complex area. However, the delimitation of biogeographical areas in eastern Brazil has relied on the simultaneous use of biotic (animal and plant distributions and vegetation physiognomy) and abiotic factors (climate, elevation), often without an explicit methodology. Here we take advantage of the availability of large numbers of vascular plant specimens and their digitized data, the existence of a well curated taxonomy for the plants of Brazil, and new biogeographic tools in order to identify bioregions (geographic areas that contain similar taxa) of eastern Brazil. To provide a classification scheme suitable to studies of lineages that differ in dispersion, species richness, and endemism, we provide three levels of grouping. While large amounts of digitized herbarium data exist, these data need to be carefully curated before it can be used. Common issues are wrong coordinates, wrong identification, specimen georeferenced to the centroid of the country, state or municipality, conflicting taxonomy, etc. The issues are highlighted by the fact that over 40% of the initial records had to be filtered out. The dataset analyzed had a comparable number of species across eastern Brazil relative to the recent taxonomic synthesis of the Brazilian flora. Using species distribution models to compensate for sampling issues due to the loss of natural vegetation in eastern Brazil we employed the network approach of Vilhena and Antonelli (2015) as  implemented in the Infomap Bioregions web application (Edler et al. 2016). We confirm regions previously recognized for both highly diversity and endemism across both coastal (Serra do Mar and Mantiqueira) and inland mountain ranges (Campos Rupestres), as well as in southern Bahia. The first network analysis divided eastern Brazil into 10 bioregions, which were clustered in five super-bioregions and divided in 23 sub-bioregions in the two additional network analyses. The super-bioregions recovered correspond to the Southern Atlantic Forest/Paraná Forests, the Northern Atlantic Forest, the Espinhaço/ Mantiqueira, the Cerrado, and the Caatinga/Diamantina. To some extent, these areas present some congruence with previously defined domains. A major incongruence is distinctiveness of the Espinhaço/Mantiqueira super-bioregion. Comparisons of species richness, endemism and overlapping of the bioregions with three other classifications (domains, ecoregions and biogeographical provinces) are presented

2 - The New York Botanical Garden, 2900 Southern BLVD, Bronx, NY, 10458, United States

Specimen Digitization.

Presentation Type: Oral Paper
Session: BIOG1, Biogeography I
Location: Virtual/Virtual
Date: Tuesday, July 28th, 2020
Time: 11:15 AM
Number: BIOG1006
Abstract ID:456
Candidate for Awards:None

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