Acclimation of seedlings of three Mexican tropical rain forest tree species to a change in light availability

ABSTRACT A comparison is made of the light acclimation potential of seedlings of three canopy species of the tropical rain forest of Los Tuxtlas, Mexico: Cordia megalantha, Lonchocarpus guatemalensis, and Omphalea oleifera. These species showed similar growth rates in a range of microhabitats. Gap dynamics were simulated by transferring plants between three environments: beneath a closed canopy, a small gap, and a large gap. Plants of all three species were able to adjust their morphology and growth rates in response to changes in light availability. Growth rates increased when plants were moved to a (larger) gap, and decreased when plants were moved to a more shaded environment. Shade-grown plants were able to acclimate faster to increasing light availability than sun-grown plants to decreasing light availability. Also, plants moved from shady to sunny conditions showed higher relative growth rates than sun control plants, whereas sun-grown plants when moved to the shade showed lower relative growth rates than shade control plants. Species differed in their response to gap dynamics. Omphalea could not acclimate morphologically to shading, but reacted faster than the other species in response to the occurrence of a large gap. Acclimation potential seemed to be related to plasticity in physiological rather than in morphological traits. Suppressed seedlings of all three species performed well in the shade, and were able to acclimate rapidly to gap-conditions.

[1]  F. Bongers,et al.  Response of Cordia megalantha Blake seedlings to gap environments in tropical rain forest , 1988 .

[2]  P. White,et al.  The Ecology of Natural Disturbance and Patch Dynamics , 1986 .

[3]  D. Clark,et al.  Seedling Dynamics of a Tropical Tree: Impacts of Herbivory and Meristem Damage , 1985 .

[4]  S. Oberbauer,et al.  Effects of light regime on the growth and physiology of Pentaclethra macroloba (Mimosaceae) in Costa Rica , 1985, Journal of Tropical Ecology.

[5]  D. Lieberman,et al.  Growth rates and age-size relationships of tropical wet forest trees in Costa Rica , 1985, Journal of Tropical Ecology.

[6]  N. Brokaw,et al.  Chapter 4 – Treefalls, Regrowth, and Community Structure in Tropical Forests , 1985 .

[7]  C. Augspurger.  Seedling Survival of Tropical Tree Species: Interactions of Dispersal Distance, Light-Gaps, and Pathogens , 1984 .

[8]  Robin L. Chazdon,et al.  PHOTOSYNTHETIC LIGHT ENVIRONMENTS IN A LOWLAND TROPICAL RAIN FOREST IN COSTA RICA , 1984 .

[9]  D. Mueller‐Dombois,et al.  RESPONSE OF METROSIDEROS POLYMORPHA SEEDLINGS TO EXPERIMENTAL CANOPY OPENING , 1984 .

[10]  F. Bazzaz.  Dynamics of Wet Tropical Forests and Their Species Strategies , 1984 .

[11]  C. Vázquez-Yanes,et al.  Ecophysiology of Seed Germination in the Tropical Humid Forests of the World: A Review , 1984 .

[12]  N. Garwood.  Seed Germination in a Seasonal Tropical Forest in Panama: A Community Study , 1983 .

[13]  Whitmore Tc.  On pattern and process in forests. , 1982 .

[14]  S. Pickett,et al.  PHYSIOLOGICAL ECOLOGY OF TROPICAL SUCCESSION: A Comparative Review , 1980 .

[15]  G. Hartshorn.  Neotropical Forest Dynamics , 1980 .

[16]  J. Denslow.  Gap Partitioning among Tropical Rainforest Trees , 1980 .

[17]  P. B. Tomlinson,et al.  Tropical Trees as Living Systems. , 1980 .

[18]  G. E. Blackman,et al.  Physiological and Ecological Studies in the Analysis of Plant Environment , 1959 .

[19]  G. E. Blackman,et al.  Physiological and Ecological Studies in the Analysis of Plant Environment VII. An Analysis of the Differential Effects of Light Intensity on the Net Assimilation Rate, Leaf-Area Ratio, and Relative Growth Rate of Different Species , 1951 .