Phenology of Tree Species in Bolivian Dry Forests1

Abstract Phenological characteristics of 453 individuals representing 39 tree species were investigated in two dry forests of the Lomerío region, Department of Santa Cruz, Bolivia. The leaf, flower, and fruit production of canopy and sub-canopy forest tree species were recorded monthly over a two-year period. Most canopy species lost their leaves during the dry season, whereas nearly all sub-canopy species retained their leaves. Peak leaf fall for canopy trees coincided with the peak of the dry season in July and August. Flushing of new leaves was complete by November in the early rainy season. Flowering and fruiting were bimodal, with a major peak occurring at the end of the dry season (August–October) and a minor peak during the rainy season (January). Fruit development was sufficiently long in this forest that fruiting peaks actually tended to precede flowering peaks by one month. A scarcity of fruit was observed in May, corresponding to the end of the rainy season. With the exception of figs (Ficus), most species had fairly synchronous fruit production. Most canopy trees had small, wind dispersed seeds or fruits that matured during the latter part of the dry season, whereas many sub-canopy tree species produced larger animal- or gravity-dispersed fruits that matured during the peak of the rainy season. Most species produced fruit annually. Lomerío received less rainfall than other tropical dry forests in which phenological studies have been conducted, but rainfall can be plentiful during the dry season in association with the passage of Antarctic cold fronts. Still, phenological patterns in Bolivian dry forests appear to be similar to those of other Neotropical dry forests.

[1]  S. Hilty.  Flowering and fruiting periodicity in a premontane rain forest in Pacific Colombia. , 1980 .

[2]  A. Gentry,et al.  Patterns of neotropical plant species diversity. , 1982 .

[3]  T. Fredericksen,et al.  Harvesting free-standing fig trees for timber in Bolivia: potential implications for forest management , 1999 .

[4]  H. G. Baker,et al.  Rainfall as a factor in the release, timing, and synchronization of anthesis by tropical trees and shrubs , 1976 .

[5]  H. G. Baker,et al.  Comparative Phenological Studies of Trees in Tropical Wet and Dry Forests in the Lowlands of Costa Rica , 1974 .

[6]  R. Borchert,et al.  Soil and Stem Water Storage Determine Phenology and Distribution of Tropical Dry Forest Trees , 1994 .

[7]  R. Borges.  Figs, malabar giant squirrels, and fruit shortages within two tropical Indian forests , 1993 .

[8]  D. Janzen.  SYNCHRONIZATION OF SEXUAL REPRODUCTION OF TREES WITHIN THE DRY SEASON IN CENTRAL AMERICA , 1967, Evolution; international journal of organic evolution.

[9]  S. H. Bullock,et al.  Phenology of canopy trees of a tropical deciduous forest in México. , 1990 .

[10]  R. Borchert.  Phenology and control of flowering in tropical trees , 1983 .

[11]  P. G. Murphy,et al.  Ecology of Tropical Dry Forest , 1986 .

[12]  P. Reich,et al.  Water stress and tree phenology in a tropical dry forest in the lowlands of Costa Rica. , 1984 .

[13]  H. G. Baker,et al.  COMPARATIVE PHENOLOGICAL STUDIES OF TREELET AND SHRUB SPECIES IN TROPICAL WET AND DRY FORESTS IN THE LOWLANDS OF COSTA RICA , 1980 .

[14]  L. González-García,et al.  Fenologia de lianas y arboles anemocoros en una selva calido-humeda de Mexico , 1991 .

[15]  Frank R. Lambert,et al.  Keystone Characteristics of Bird-Dispersed Ficus in a Malaysian Lowland Rain Forest , 1991 .

[16]  J. Terborgh,et al.  The Phenology of Tropical Forests: Adaptive Significance and Consequences for Primary Consumers* , 1993 .