Catastrophic hydraulic failure and tipping points in plants

Area of Science:

• Plant Physiology
• Ecology
• Biophysics

Background:

• Plant water transport forms a continuous chain from soil to leaves.
• Failures in this chain, like xylem embolism, reduce transpiration and photosynthesis.
• These failures are analogous to 'catastrophe theory' in dynamical systems, representing tipping points.

Purpose of the Study:

• To view plant hydraulics through the lens of catastrophe theory at multiple spatial scales.
• To analyze bubble expansion, organ-level embolism vulnerability, and whole-plant biomass in this framework.
• To examine the hydraulic safety-efficiency tradeoff, hydraulic segmentation, and maximum plant transpiration.

Main Methods:

• Application of catastrophe theory to plant hydraulic failure.
• Analysis of mechanisms at fine (pit membranes, cell walls), intermediate (xylem networks), and large (soil-tree pathways) scales.
• Examination of plant hydraulics using bubble expansion, embolism vulnerability, and biomass as proxies.

Main Results:

• Catastrophe theory provides a framework for understanding tipping points in plant hydraulics.
• Hydraulic failure mechanisms are discussed across various spatial scales.
• The study highlights understudied areas requiring further research in plant hydraulics.

Conclusions:

• Plant hydraulic failure can be conceptualized as a catastrophe across multiple spatial scales.
• Understanding these tipping points is crucial for predicting plant responses to environmental changes.
• Further research is needed to address knowledge gaps in plant hydraulic function.