PHENOLOGICAL PATTERNS OF WOODY VEGETATION AT TINIGUA PARK, COLOMBIA: METHODOLOGICAL COMPARISONS WITH EMPHASIS ON FRUIT PRODUCTION

Abstract

Phenological patterns have a great influence on community ecology. I have quantifiedfruit abundance using fruit traps, phenological transects, and observations on markedtrees of selected species. All methods showed the main peaks of fleshy fruitproduction between the dry period and the middle of the rainy season. Wind, water,and mechanically dispersed seeds showed a peak of production at the dry period.According to the number of individuals on transects, flower abundance showedpredominantly two peaks, one at the end of the rainy period and one in the dryperiod. This pattern was positively correlated with solar irradiance estimates anddifferences between maximum and minimum temperatures, which tend to occur ondry days when the activity and abundance of pollinating insects seemed to be high.There was also a good correlation between relative day length and the density offlowering individuals, which suggest that this variable could trigger floweringpatterns. Although many species lose their leaves in the dry period, the productionof new leaves does not seem to be associated with any particular season. I used anew method to quantify fruit production for each species (in kg/ha), based onphenological transects, corrected visual estimates, and dry fruit weights. The matureforest produced more fruits than the other forests, and the flooded forest showedless fruit production during the dry season and the beginning of the rainy period. Incontrast, average density of fruiting trees was similar or slightly greater in the floodedforests than in terra-firme forests during the middle part of the rainy period. Finally,I estimated how long the transects should be in order to get adequate estimates offruit production, and I found that in general at least 7 km are necessary to get goodestimates for terra firme forests at Tinigua.