INVESTIGADORES
MARTINEZ PASTUR Guillermo Jose
artículos
Título:
Diameter growth: Can live trees decrease?.
Autor/es:
MARTÍNEZ PASTUR G; LENCINAS MV; CELLINI JM; MUNDO I
Revista:
Forestry
Editorial:
Oxford Journals
Referencias:
Año: 2007 vol. 80 p. 83 - 88
ISSN:
0015-752X
Resumen:
Growth refers to an increase in dimensions with time and is implicit in the expected continual
increase in tree dimensions. Tree diameters, however, could decrease during the growing season due
to water depletion. Annual negative growth measurements are usually attributed to human error
and not to other physiological or physical processes. Although seasonal and diurnal fl uctuations
of diameter have been well documented, perennial decrement of diameter has not been the focus
of physiological research. The aim of this work was to analyse the potential causes of decrease in
annual diameter growth related to tree mortality due to self-thinning in Nothofagus pumilio forests
and to quantify the variations in water depletion of the tree trunks. Some trees did present negative
annual diameter increments associated with a water content decrease in the trunks (77 per cent in
live trees compared with 56 per cent in recently dead individuals), which produced a contraction
(more than 8 per cent of the initial diameter) in the wood and the bark. Trees could survive during
2 5 growth seasons with continual decreases in their diameters (14 per cent, standard error 5
per cent of the trees in the studied stand) until the water content reached a limit where mortality
resulted. Therefore, the occurrence of data showing a diameter decrease in successive forest
inventories may be due to physiological and physical processes in the natural dynamics of the stand,
and not exclusively be explained away as the results of human measurement errors.
and to quantify the variations in water depletion of the tree trunks. Some trees did present negative
annual diameter increments associated with a water content decrease in the trunks (77 per cent in
live trees compared with 56 per cent in recently dead individuals), which produced a contraction
(more than 8 per cent of the initial diameter) in the wood and the bark. Trees could survive during
2 5 growth seasons with continual decreases in their diameters (14 per cent, standard error 5
per cent of the trees in the studied stand) until the water content reached a limit where mortality
resulted. Therefore, the occurrence of data showing a diameter decrease in successive forest
inventories may be due to physiological and physical processes in the natural dynamics of the stand,
and not exclusively be explained away as the results of human measurement errors.
Nothofagus pumilio forests
and to quantify the variations in water depletion of the tree trunks. Some trees did present negative
annual diameter increments associated with a water content decrease in the trunks (77 per cent in
live trees compared with 56 per cent in recently dead individuals), which produced a contraction
(more than 8 per cent of the initial diameter) in the wood and the bark. Trees could survive during
2 5 growth seasons with continual decreases in their diameters (14 per cent, standard error 5
per cent of the trees in the studied stand) until the water content reached a limit where mortality
resulted. Therefore, the occurrence of data showing a diameter decrease in successive forest
inventories may be due to physiological and physical processes in the natural dynamics of the stand,
and not exclusively be explained away as the results of human measurement errors.