Determinantes da raridade das espécies e seus efeitos sobre a estrutura de comunidades biológicas

• Ano de defesa: 2018
• Autor(a) principal: Sgarbi, Luciano Fabris
• Orientador(a): Melo, Adriano Sanches
• Banca de defesa: Melo, Adriano Sanches , Cassemiro, Fernanda, Almeida Neto, Mário, Teresa, Fabrício Barreto, Pereira, Rodrigo Augusto Santinelo
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Goiás
• Programa de Pós-Graduação: Programa de Pós-graduação em Ecologia e Evolução (ICB)
• Departamento: Instituto de Ciências Biológicas - ICB (RG)
• País: Brasil
• Palavras-chave em Português: Raridade; Estrutura de comunidades; Gradientes ambientais
• Palavras-chave em Inglês: Rarity; Community structure; Environmental gradients
• Área do conhecimento CNPq: CIENCIAS BIOLOGICAS::ECOLOGIA
• Link de acesso: http://repositorio.bc.ufg.br/tede/handle/tede/8612

A recurrent pattern seen in nature is that species vary in abundance among sites, being common in a few sites and rare at the majority of sites. This intraspecific distribution of abundance, in turn, generates an excess of rare species in biological communities. This excess may cause problems in data analyses as datasets include many zeros. In this thesis I studied the causes of species rarity and how the excess of rare species influence the detection of patterns at the community level. In the first chapter I observed that species classified as rare were common in other habitat types, in other sites elsewhere, and in other years. However, among these three factors, the rarity was explained mainly by the habitat type. In the second chapter I observed that species tend to become rarer as they distance themselves (above, below or in both directions) from their optimal elevation. This pattern was quite robust and independent of taxonomic group or geographic region. In the third chapter, I observed that remotion of rare species in general did not have effects on the recovery of community structure patterns. In addition, the effect of that remotion of rare species was similar to that observed for the common species exclusion or random species exclusion.