INVESTIGADORES
SCHOLZ Fabian Gustavo
artículos
Título:
Plant- and Stand level variation in biophysical and physiological traits along tree density gradients in the Cerrad
Autor/es:
FABIAN G. SCHOLZ, SANDRA J. BUCCI, GUILLERMO GOLDSTEIN, FREDERICK C. MEINZER, AUGUSTO C. FRANCO, ANA SALAZAR
Revista:
BRAZILIAN JOURNAL OF PLANT PHYSIOLOGY
Editorial:
Brazilian Society of Plant Physiology
Referencias:
Año: 2008 vol. 20 p. 217 - 231
ISSN:
1677-0420
Resumen:
The objective of this study was to characterize and understand morphological and physiological variation in traits
related to water economy, at the plant and stand level, along a gradient of tree density in a Neotropical savanna
(Cerrado). Cerrado plots subjected to long-term fertilization and gallery forests were also included in the analysis to
expand the axes of ecosystem variation. Consistent changes in stand level biophysical traits observed along the
gradient of increasing tree density included a decrease in weighted-average wood density, and increases in leaf surface
area per plant, leaf specific hydraulic conductivity, specific leaf area and stomatal conductance. A conceptual model of
biophysical, morphological and physiological trait interactions was developed in an attempt to explain determinants of
hydraulic architecture and variations in water economy of Cerrado trees. Consistent with the model minimum leaf water
potentials were higher, during the dry season, in low wood density trees compared to high wood density trees, and
higher leaf water potential was associated with higher stomatal conductance. On the other hand, variations in stand
level physiological and morphological traits along the tree density gradient could not be explained by variations in
single environmental factors. Some of the potential contributing factors are: higher concentration and availability of soil
nutrients in the upper portion of the gradient where tree density is greatest and constrains to tree establishment and
growth by waterlogging and presence of concretions in the soil profile where tree density is lowest.
Key words: gallery forest, hydraulic architecture, nutrients, savannas, specific leaf area, wood densitygallery forest, hydraulic architecture, nutrients, savannas, specific leaf area, wood density