中文摘要：

不同材性树种的解剖、叶脉分布等结构性状差异会影响树木的水分运输效率和水分利用策略,进而限制树木的生存、生长和分布。然而,材性对叶导水率、水力脆弱性及其潜在的权衡关系的影响尚不清楚。该研究选择东北温带森林中不同材性的9种树种（散孔材：山杨（Populus davidiana）、紫椴（Tilia amurensis）、白桦（Betula platyphylla）;环孔材：蒙古栎（Quercus mongolica）、水曲柳（Fraxinus mandshurica）、胡桃楸（Juglans mandshurica）;无孔材：红皮云杉（Picea koraiensis）、樟子松（Pinus sylvestris var.mongolica）、红松（Pinus koraiensis）,测量其基于叶面积和叶质量的叶导水率（Karea和Kmass）、水力脆弱性（P50）、膨压丧失点水势（TLP）及叶结构性状,以比较不同材性树种叶水力性状的差异,并探索叶水力效率与安全的权衡关系。结果表明：3种材性树种的Karea、Kmass和P50均差异显著（p〈0.05）。无孔材树种的Karea和Kmass最低,而散孔材和环孔材树种差异不显著;环孔材树种P50最高,而散孔材和无孔材树种差异不显著。Karea和Kmass均与P50显著负相关（p〈0.05）,但散孔材、环孔材和无孔材树种的相关关系分别呈线性、幂函数和指数函数关系。这表明叶水力效率与安全之间存在一定的权衡关系,但该关系受树木材性的影响。Kmass与TLP显著负相关（p〈0.01）,其中散孔材和环孔材树种呈线性负相关,无孔材树种呈负指数函数关系;P50随TLP的增加而增加,这表明树木在面临水分胁迫时,其质外体和共质体抗旱阻力共同协调保护叶片活细胞,防止其水分状况到达临界阈值。Kmass与叶干物质含量、叶密度、比叶重均显著负相关,而P50与之显著正相关（p〈0.01,P50与比叶重的关系除外）,表明树木叶水力特性的变化受相同叶结构特性驱动,树木增加对水力失调的容忍需要在叶水力系统构建上增加碳投资?

英文摘要：

Aims Trees with different wood properties display variations in xylem anatomy and leaf vein structure, which may influence tree water transport efficiency and water-use strategy, and consequently constrain tree survival, growth and distribution. However, the effects of wood properties on leaf hydraulic conductance and vulnerability and their potential trade-offs at leaf level are not well understood. Our aims were to examine variations in leaf hydraulic traits of trees with different wood properties and explore potential trade-offs between leaf hydraulic efficiency and safety. Methods Nine tree species with different wood properties were selected for measuring the leaf hydraulic traits, including three diffuse-porous species（Populus davidiana, Tilia amurensis, Betula platyphylla）, three ring-porous species（Quercus mongolica, Fraxinus mandshurica, Juglans mandshurica）, and three non-porous species（Picea koraiensis, Pinus sylvestris var. mongolica, Pinus koraiensis）. Four dominant and healthy trees per species were randomly selected. The hydraulic traits measured included leaf hydraulic conductance on leaf area（Karea） and dry mass（Kmass） basis, leaf hydraulic vulnerability（P50）, and leaf water potential at turgor loss point（TLP）, while the leaf structural traits were leaf dry mass content（LDMC）, leaf density（LD） and leaf mass per unit area（LMA）. Important findings The Karea, Kmass, and P50 differed significantly among the tree species with different woody properties（p 0.05）. Both Karea and Kmass were the lowest for the non-porous trees, and did not differ significantly between the diffuse-porous and ring-porous trees. The ring-porous trees had the highest P50 values, while thediffuse-porous and non-porous trees showed no significant differences in P50. Both Karea and Kmass were negatively correlated with P50（p〈0.05） for all the trees, and the relationships for the diffuse-porous, ring-porous, and non-porous trees were fitted into linear, power, exponential functions