Acta Botánica Venezuelica
versión impresa ISSN 0084-5906
Resumen
RAMIREZ, Nelson. Correlations between the reproductive phenology of vegetation and climate variables in the Venezuelan Central Plain. Acta Bot. Venez. [online]. 2009, vol.32, n.2, pp.333-362. ISSN 0084-5906.
Flowering, unripe fruit production, and fruit maturation were evaluated for 171 species belonging to 57 families of angiosperms in the vegetation of the Venezuelan Central Plains at Estación Biológica de los Llanos. The main goal of this study was to establish the correlation between reproductive phenology and six climatic variables according to plant life form, habitat, and overall community. Monthly values of precipitation and relative humidity are positively correlated, and monthly values of evaporation and temperature are negatively correlated with the number of lianas, perennial herbs, and annual herbs, the contrary was found for the number of tree species with flower. The number of plant species with flowers was negatively correlated with temperature and evaporation, and positively correlated with relative humidity and precipitation for forest-savanna transition, savanna, disturbed area, and overall community. Insolation was negatively correlated with flowering in the forest and forest-savanna transition. Precipitation was only correlated with the number of flowering plant species in the forest. The number of species with unripe fruits was positively correlated with the relative humidity for shrubs, perennial herbs, and annual herbs, and with precipitation for shrubs and perennial herbs. On the contrary, species with unripe fruits was negatively correlated with radiation for trees, temperature for herbaceous species, and evaporation for shrubs and herbaceous species. The number of lianas with unripe fruits was only correlated with temperature. The total number of species with unripe fruits was negatively correlated with temperature and evaporation for the four habitats, and positively correlated with the relative humidity at the community level. In addition, unripe fruits were negatively correlated with radiation and positively correlated with precipitation in the forest. Fruit maturation of shrubs and perennial herbs were negatively correlated with temperature and evaporation, and positively correlated with relative humidity. In addition, fruit maturation of lianas were negatively correlated with relative humidity and precipitation and positively correlated with evaporation. The number of plant species with ripe fruits was only positively correlated with radiation for the forest. In general, the reproductive phenology was positively correlated with climatic variables related to water availability and negatively with the climatic variables associated with water deficiency. These correlations suggest that reproductive phenology may co-vary according to particular attributes of the climate depending upon plant life form and the habitat of the community.
Palabras clave : Climatic variables; flowering; fruit phenology; habitat; life form; ripe fruit; unripe fruit; Venezuela.