%0 Journal Article
%T 植物木质部空穴和栓塞化的发生条件与恢复机理<br>Occurrence Conditions and Recovery Mechanism of Cavitation and Embolization in Plant Xylem
%A 尚念科
%A 孔令刚
%J Botanical Research
%P 585-589
%@ 2168-5673
%D 2022
%I Hans Publishing
%R 10.12677/BR.2022.115070
%X 空穴是压力由常压降低到负压的过程中产生的，当压力由负压升高至常压时，空穴就会逐渐消除，而不是必须要靠较高的正压。形成空穴的气核是来源于水中溶解的气体，压力降低时从水中逸出，压力恢复后又重新溶于水中。压力变化是决定空穴发生和消除的最直接因素，低水势与空穴的发生只是一种伴随关系而不是因果关系。利用气体溶解平衡原理，通过压力变化研究空穴的发生与消除，更容易发现和了解空穴的本质和变化规律，对诸多理论和实践现象能做出更合理的解释。<br />
The cavity is generated in the process of reducing the pressure from normal pressure to negative pressure. When the pressure increases from negative pressure to normal pressure, the cavity will be gradually eliminated instead of relying on a higher positive pressure. The gas nucleus that forms the cavity is derived from the gas dissolved in the water, which escapes from the water when the pressure is reduced, and re-dissolves in the water when the pressure is restored. The change of pressure is the most direct factor which determines the occurrence and elimination of cavitation, while the low water potential and cavitation is only a concomitant relationship rather than a causal relationship. It is easier to discover and understand the essence and changing rules of the cavity by using the principle of gas dissolution equilibrium and studying the occurrence and elimination of the cavity through pressure changes. We can make more reasonable explanations for many theoretical and practical phenomena.
%K 空穴，栓塞，溶解平衡，负压，水势<br>Cavity
%K Embolism
%K Dissolution Equilibrium
%K Negative Pressure
%K Water Potential
%U http://www.hanspub.org/journal/PaperInformation.aspx?PaperID=56184