中文摘要：

为探究植物叶功能性状与压力—容积（PV）曲线参数间的相关性,选取黄龙山南缘的11种典型落叶木本植物,对其叶性状（叶厚度、叶密度、比叶质量和叶干物质率）及PV曲线参数（饱和渗透势、膨压损失点对应的渗透势、膨压损失点对应的相对含水量及束缚水含量）进行了测定。结果表明：供试树种比叶质量与叶密度呈极显著正相关,但与叶厚度无显著相关性,叶密度与叶厚度间呈显著负相关; 叶膨压损失点渗透势与饱和渗透势间呈显著正相关,但与束缚水含量呈显著负相关; 比叶质量与膨压损失点相对含水量呈显著负相关。表明影响该区植物比叶质量的主要因素为叶密度,叶密度与厚度之间存在一定的制约关系; 渗透物质的积累和原生质体体外调节是造成该区物种渗透势降低的主要原因; 高比叶质量的物种相对含水量低,耐旱性相对较强,揭示了比叶质量高的物种抗旱的生理机制。

英文摘要：

In this study, 11 typical deciduous woody plants at southern edge of Huanglong Mountain in Shaanxi Province were selected to explore relationships between leaf traits, including leaf dry mass per area（LMA）, leaf thickness （LT）, leaf density（LD）and leaf dry mass content（LDMC）, and pressure-volume curve （PV curve）parameters such as the maximum osmotic potential corresponding to saturated water content（ψsat）, the osmotic potential at turgor loss point（ψtlp）, the relative water content at turgor loss point（RWCtlp）and the bounding water percentage （B）. The results showed that： LMA was positively correlated with LD but uncorrelated with LT, LD was negatively correlated with LT. The ψtlp was positively correlated with ψsatand negatively correlated with B across tested species. LMA was negatively correlated with RWCtlp. All these showed that LMA variation was caused by LD rather than LT, there was a tradeoff relationship between LD and LT. Solute accumulation and apoplastic adjustment were the major reasons of decreased ψtlp. Higher LMA was associated with lower RWCtlp, demonstrating the physiological basis why species with higher LMA also have stronger drought-tolerance.