Drop impact dynamics on the hydrophobic leaf surface of an aquatic plant: a case study of Pistia stratiotes.

This article focuses on the dynamics of water drop impacts on the hydrophobic leaves of Pistia stratiotes, an invasive aquatic plant known as water lettuce. Using high-speed cameras, the study quantitatively analyzed how water drops of varying kinetic energies interact with the leaf’s complex micro- and macrostructure—comprising uniseriate trichomes, ridges, and veins—when placed on the water surface. Three distinct splash behaviors were identified: drop receding and stabilization, drop receding with late droplet ejection due to elastic leaf deformation, and drop breakup with early and late droplet ejection. The findings highlight that the leaf’s surface features and mechanical response significantly influence droplet formation, splash characteristics, and energy transfer, which has implications for understanding pathogen dispersal and improving herbicide application strategies in aquatic environments.