Banca de QUALIFICAÇÃO: AUGUSTO CÉSAR DA SILVA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : AUGUSTO CÉSAR DA SILVA
DATA : 16/10/2017
HORA: 13:30
LOCAL: Sala de Reuniões – Departamento de Ecologia (DECOL)
TÍTULO:

Floristic groups and their environmental relations in the Caatinga seasonally dry vegetation, northeastern of South America.

PALAVRAS-CHAVES:

Biogeography, floristic dissimilarity, endemism, distribution patterns, classification of vegetation, semi-arid environments, seasonally dry forests. 

PÁGINAS: 36
GRANDE ÁREA: Ciências Biológicas
ÁREA: Ecologia
RESUMO:

Abstract

Aim Biogeographical regionalizations are representations of the organization of organisms in the geographical space in function of the various biotic to abiotic factors to past or present. The aim was propose a vegetacion classification of Caatinga based in floristic groups, identifying the factors main that determine the grups distribuition patterns.

 

Location Caatinga phytogeographical domains

 

Methods We compiled 266 floristic inventories that to composse the data base “Caaporã”. The floristic inventories were used to build a species-by-site matrix and used unconstrained ordination and clustering techniques to identify the number of floristic groups in Caatinga. We applicated applied an interpolation method to map axes of compositional variation over the whole extent of the Caatinga and then classified the compositional dissimilarity according to the number of floristic groups identified a priori. In addition, we performed a hierarchical analysis (UPGMA) to verify the relationship between the groups. We used multinomial logistic regression models with AIC and wAICc criteria to investigate the influence of contemporary productivity, topographic complexity, historical climate shifts and human footprint in explaining the floristics groups.

 

Results We identified a total of 2872 species of plants organized into nine floristic groups, some are distributed latitudinally (North-South), while others are restricted to certain specific regions in the southern and western portions of the domain. The results of the multinomial regression show that the dryness index (AI) individually was the variable that best explains the distribution pattern of the groups. Therefore productivity was the significant model that best describes the distribution pattern of the groups. The models evaluating soil, topography and historical variables were not significant.

MEMBROS DA BANCA:
Presidente - 1837921 - ALEXANDRE FADIGAS DE SOUZA
Interno - 1678202 - CARLOS ROBERTO SORENSEN DUTRA DA FONSECA
Interno - 006.988.680-64 - GUILHERME GERHARDT MAZZOCHINI - UFRN