Variations in functional traits and resilience of Inga vera subsp. affinis under flooding and drought conditions

The dynamics of a plant population are influenced by both biotic and abiotic factors that interfere with the phenotype of the individual, indicating how species develop in the occupied environment. Riparian plant species are subject to environmental fluctuations, such as periodic flooding regimes and severe droughts, which may result from climate change.

The aim of this study was to evaluate the morphological growth responses of individuals of Inga vera subsp. affinis (DC.) T.D.Penn. in controlled drought and flooding conditions by observing variations in functional traits using controlled experiments.

Individuals were subjected to partial flooding and dry periods, and functional traits, such as leaf area, root height and dry mass, were analysed. The difference between treatments was tested using unifactorial statistical analysis of variance (ANOVA).

Fifteen-day-old individuals of Inga vera subsp. affinis kept under flooding conditions showed lower root height and dry mass compared to plants exposed to drought treatment; 50-day-old plants under flooding conditions also presented lower root dry mass than did plants in drought treatment, maintaining the result after the resilience period.

Root dry mass was the most affected variable in individuals of Inga vera subsp. affinis under flooding conditions, even after the recovery period. In general, plants in the control and drought treatments did not differ significantly considering the analysed variables.

Given the current climate change conditions, an increase in the frequency and duration of extreme events, such as floods and droughts, is expected. Thus, understanding how phenotypical traits of species already adapted to flooding conditions behave under water stress and waterlogged conditions for longer periods of time is essential to explain plant responses and predict future survival scenarios for the species.