High temperatures and nutrient limitations in deserts challenge plant survival. Large temperature oscillations and droughts typical of cold deserts can result in cavitation, the precipitation of dissolved air within a xylem vessel. If xylem vessels are closely packed, then a cavitation event may expand to neighboring vessels, resulting in runaway embolism, and potentially paralyze the vital functions of the plant.
 Hydraulic sectoriality, where the plant is functionally composed of independent hydraulic units, has been suggested as a strategy to decrease the risk associated with cavitation. This can occur by increasing xylem vessel isolation and/or increasing the physical modularity of the plant. Furthermore, hydraulic sectoriality... |