Chain Guadarrama, Adina

Understanding plant community assembly mechanisms in highly diverse neotropical forests through the assessment of functional beta diversity - 35 páginas : 8 ilustraciones, 5 tablas ; 21.59 x 27.94 cm

Tesis (Ph. D.) -- CATIE. Escuela de Posgrado. Turrialba (Costa Rica), University of Idaho, 2014.

Bibliografía páginas 26-30

The mechanisms controlling tree species assembly in Neotropical forests are still debated. A
taxonomic approach has traditionally been used to assess vegetation response to
environmental and spatial predictors, but the information held in species functional traits
should further elucidate the factors determining community turnover in these diverse forests.
To test hypotheses related to environmental deterministic and dispersal assembly of
Neotropical forest communities, we assessed patterns of taxonomic and functional turnover,
or beta diversity, across broad geographic and environmental gradients. Using abundance and
functional trait data for dominant trees and palms distributed in 127 forest plots across a
northern Costa Rican landscape, we quantified the influence of environmental and spatial
predictors on taxonomic and functional composition variation (variation partitioning) and
assessed patterns of taxonomic and functional turnover with increasing geographic and
environmental distances (Mantel correlation tests and Mantel correlograms). Environmental
predictors explained greater proportion of taxonomic and functional composition variation
than spatial predictors. Functional and taxonomic turnover increased with increasing
geographic and environmental differences between plots, but once controlling for
environmental change spatial patterns in taxonomic and functional composition were no
longer observed. However, spatial structure in residual taxonomic and functional turnover was
observed when examining individual distance lags. This, together with the pure effect of
spatial predictors, suggests that community turnover is also explained by geographic
proximity between plots alone. Our results indicated the existence of a scale-dependent
interaction between deterministic and stochastic community assembly, showing that
community turnover results from species recruitment along regional spatially structured
environmental gradients, and from species limited dispersal at local scales. As such the
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assessment of functional turnover hold great potential for estimating community assembly
mechanisms in this biome.

http://hdl.handle.net/11554/8122


ECOLOGIA FORESTAL
BOSQUE TROPICAL
ARBOLES
ESPECIES
TAXONOMIA
COMPOSICION BOTANICA
DINAMICA DE POBLACIONES
POBLACION VEGETAL
CARACTERISTICAS DEL RODAL
BIODIVERSIDAD
FACTORES AMBIENTALES
USO MULTIPLE DEL BOSQUE
RECURSOS FORESTALES
COMUNIDADES RURALES
DESARROLLO DE LA COMUNIDAD
GRADIENTES ALTITUDINALES
RASGOS FUNCIONALES


COSTA RICA