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选取加杨、刺槐、白榆、沙棘和榛木５个树种，测定一年生小枝的导水率和水势，绘制出各树种的脆弱曲线。结果表明，这几个树种一年生枝木质部栓塞脆弱性的种间差异明显，其中加杨和沙棘最为脆弱，其次为刺槐、白榆和榛木。这种种间差异可能与导管壁的厚度和导管间纹孔膜上纹孔口的长径有关。耐旱树种并非对木质部空穴或栓塞的抵抗能力就强；植物遭遇水分胁迫时，在一定水势范围内，木质部栓塞降低导水率从而可减少水分丧失，这可能是树种适应干旱条件的方式之一。脆弱曲线可以提供有关植物生理生态行为的信息，文中对树种脆弱性和耐旱性的关系以及脆弱曲线的应用价值进行了讨论
Five species of poplar, acacia, elm, seabuckthorn and hazelnut were selected to measure the water conductivity and water potential of annual branches, and the fragility curve of each tree species was drawn. The results showed that among the species, the interspecific differences in fragility of annual xylem emboli were obvious. Among them, poplar and seabuckthorn were the most vulnerable, followed by acacia, elm and hazelnut. This interspecific difference may be related to the thickness of the catheter wall and the major axis of the stomata in the inter-canal parenchyma. Drought-tolerant species are not resistant to cavities or embolism in xylem. When plants are exposed to water stress, xylem embolization reduces the water conductivity and thus reduces the water loss within a certain water potential, which may be the way for species to adapt to drought conditions one. Vulnerability curves can provide information on plant physiological and ecological behaviors. The relationship between tree species vulnerability and drought tolerance and the application value of vulnerability curves are discussed