水分在木质部输导中空化作用和栓塞修复的热力学探讨

A Thermodynamics Study on Cavitation and Embolism Repair in Xylem During Water Transportation

该文对木质部的空化作用和栓塞修复的机制作了深入的探讨，指出木质部内的微小气泡可处于稳定平衡状态，它们只是在木质部压力势降低，超过某一阈值时才膨胀、破裂，形成空腔。在压力势升高时，水分沿已空化了的导管（或管胞）壁重新分布。一旦压力势升高，超过另一阈值，空腔内的气体将回缩，水蒸气将凝聚，最终重新成为稳定的微小气泡，栓塞解除。

The mechanism of cavitation and embolism repair in xylem is studied in this paper.The conclusion is that the small bubbles can be in a stable equilibrium state. Only if the pressure potential in the xylem decreases and passes the threshold, they will expand, burst and finally take a shape of lumen. When the pressure potential increases, the water will spread out along the wall of empty vessel(or tracheid).After another threshold is passed,the gas in the empty cavity will contract,the vapour will condense, and form some stable bubbles again. Then the embolism is dissolved.