What is the current status of phenological studies of herbaceous species from tropical dry forests and savannas in the Neotropical region?

Phenology studies the life cycle of living beings, relating them to emerging environmental changes. Although dry tropical forests and savanna formations in the Neotropics harbor rich diversity and endemism of herbaceous plants, this component has received less attention in phenological studies. Therefore, understanding its dynamics is crucial to comprehend the functioning of these ecosystems and to promote conservation strategies. In this study, we conducted a comprehensive scientific mapping of phenological studies of herbaceous species carried out in the dry forests and savannas of the Neotropical region over 11 years (2009-2020). Our results highlight a concentration of studies in 2011 (24%) and in the Cerrado Biome (48%), mainly through direct observations in natural environments (96%) in short-term studies (76%). Many studies did not detail the plant's life form (64%), with a predominance of community studies (80%) focusing on reproductive phenophases. Correlations between phenophases and abiotic factors were common (76%), while biotic factors were less explored (28%). We recommend comprehensive studies that consider the diversity of herbaceous species in the Neotropics, incorporating longer-term experiments to observe subsequent generations of annual species and the different growth stages of perennial herbs. The intricate interactions within herbaceous populations deserve attention and offer valuable insights into understanding Neotropical transformations. Prioritizing the relationship between herbaceous phenology and biotic and environmental factors is essential for understanding the dynamics of different vegetation formations and their future in the face of predicted climate changes.