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Previous issue date: 2010-02-22 / Financiadora de Estudos e Projetos / Plants have traits against herbivory that may occur together and increase defense efficiency. We tested whether there are defense syndromes in a cerrado community and, if so, whether there is a phylogenetic signal in them. We measured nine defense traits from a woodland cerrado community in southeastern Brazil. We tested the correlation between all pairs of traits and grouped the species into defense syndromes according to their traits. Most pairwise correlations of traits were complementary. Plants with lower specific leaf area also presented tougher leaves, with low nitrogen, more trichomes, and tannins. We found five syndromes: two with low defenses and high nutritional quality, two with high defenses and low nutritional quality, and one with traits compensating each other. There were two predominant strategies against herbivory in cerrado: tolerance and low nutritional quality syndromes. Phylogeny was not determining the suite of traits species presented; so, herbivory could be regarded as a biotic factor selecting these traits. Complementarity allows species coexistence and more efficient use of niche. Originality of a species is how much that species contributes to rarity of traits. Here we (1) tested the relation between abundance and both phylogenetic and phenotypic originalities and (2) compared abundance-based extinctions to random ones. We measured nine defense traits, phylogenetic information and abundance from a woodland cerrado community in southeastern Brazil. Abundance was not related to neither phylogenetic nor functional originalities; phylogenetic and phenotypic originalities were not related. Abundance-based extinctions were not different from random. However, the originalities were concentred in few species and four of the more original species were among the rarest. These species contribute to rarity of traits more than common ones and they may contribute to compensatory dynamics and to maintenance of community stability. Thus, species abundance may not be a predominant factor to the maintenance of functions in cerrado. / As plantas possuem tracos contra herbivoria que podem ocorrer conjuntamente e aumentar a eficiencia da defesa. Testamos se ha sindromes de defesa em uma comunidade de plantas do cerrado e caso haja, se elas apresentam sinal filogenetico. Medimos nove tracos de defesa em uma comunidade de cerrado sensu stricto no sudeste do Brasil. Testamos a correlacao entre todos os pares de tracos e agrupamos as especies em sindromes de defesa de acordo com os tracos. A maioria das correlacoes par a par dos tracos foi complementar. Plantas com menores areas foliares especificas apresentaram tambem folhas duras, com menos nitrogenio, com mais tricomas e com taninos. Encontramos cinco sindromes: duas com baixos valores de defesa e alta qualidade nutricional, duas com altos valores de defesa e baixa qualidade nutricional e uma com tracos compensando uns aos outros. Houve duas estrategias de defesa contra herbivoria predominantes no cerrado: as sindromes de tolerancia e de baixa qualidade nutricional . Filogenia nao determinou o conjunto de tracos que as especies apresentaram; entao, postulamos que a herbivoria atua como um fator biotico selecionando esses tracos. A complementaridade permite a coexistencia das especies e um uso mais eficiente do nicho. Originalidade de uma especie e o quanto aquela especie contribui para a raridade de tracos. Testamos a relacao entre abundancia e as originalidades filogenetica e fenotipica e comparamos a extincao baseada na abundancia com extincoes aleatorias. A abundancia nao esteve relacionada com as originalidades, que por sua vez, nao estiveram relacionadas entre si. Extincoes baseadas na abundancia nao diferiram do acaso. Entretanto, as originalidades estiveram concentradas em poucas especies e quatro das mais originais estavam entre as mais raras. Essas especies contribuiram para a raridade de tracos mais do que as especies comuns e podem contribuir para dinamicas compensatorias e manutencao da estabilidade da comunidade. Logo, a abundancia das especies pode nao ser um fator predominante na manutencao das funcoes no cerrado.
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufscar.br:ufscar/1971 |
| Date | 22 February 2010 |
| Creators | Silva, Danilo Muniz da |
| Contributors | Batalha, Marco Antônio Portugal Luttembarck |
| Publisher | Universidade Federal de São Carlos, Programa de Pós-graduação em Ecologia e Recursos Naturais, UFSCar, BR |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFSCAR, instname:Universidade Federal de São Carlos, instacron:UFSCAR |
| Rights | info:eu-repo/semantics/openAccess |
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