Air invasion in a transpiring biomimetic leaf-on-chip

Global warming will lead to increasingly severe droughts and threatens most of the forests across the globe [1]. Trees facing drought conditions are particularly threatened by the formation of air embolisms, which hinder the flow of sap and could ultimately result in their demise. Within the context of leaves, the occurrence of embolisms has been observed to spread intermittently and possibly result in catastrophic events [2]. The utilization of PDMS-based biomimetic leaves for simulating evapotranspiration [3] has demonstrated that in a linear configuration, the existence of a slender constriction in the channel allows for the creation of intermittent embolism propagation. This intermittent dynamics arises from the interaction between the elasticity of the biomimetic leaf's venation structure and the capillary forces at the air/water interfaces [4].

During this presentation, I will demonstrate the propagation of embolism within a more complex biomimetic network that emulates diverse leaf venation patterns. By adjusting the sizes of constrictions and coordinating the network, we can faithfully replicate the primary characteristics of embolism development observed in natural leaves. These features include intermittency, trajectory patterns and hierarchical structures, which we can replicate through both experimental and numerical methods. To conclude, we will explore the significance of our approach in terms of materials and structure in real plants.