Vegetative and reproductive phenology in seasonal climate vegetation: phenological complementarity between woody and herbaceous plants in the Brazilian Chaco

Abstract

Plant growth and reproduction patterns may be closely associated with environmental seasonality, but the high diversity of plant strategies has revealed complex phenological patterns. Here, we evaluate the occurrence, duration, and seasonality of vegetative and reproductive phenophases of the Brazilian Chaco vegetation. In addition, we summarize the results of a systematic literature review about the phenology of herbaceous and woody plants in different types of seasonal vegetation in the South American Dry Diagonal. Woody plants have a high intense leaf fall and low leaf flush during the dry season in the Brazilian Chaco, whereas in herbaceous plants these phenophases have more fluctuations. In both types, flowering and fruiting are continuous, not uniform, and mainly concentrate during the rainy season. However, woody species present two intensity peaks independent of rainfall, mean temperature, photoperiod, or soil water availability. In turn, in herbaceous species, flowering and fruiting responded to local climatic variables and photoperiod, presenting a peak of intensity during the rainy season. The rainy season plays an important role in plant growth and reproduction in seasonal climates around the world, mainly due to the energetic demand for plants. Like other vegetation types with seasonal climates, particularly in the South American Dry Diagonal, the Brazilian Chaco presents a wide range of phenological patterns, with generally different patterns between woody and herbaceous species. Community-level phenological studies conducted in areas with a seasonal climate have globally focused only on reproduction in relation to vegetative phenology, mostly ignoring herbaceous flora. Here, we emphasize that the phenological complementarity between the woody and herbaceous components is of great importance in maintaining the availability of resources.