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过去几年,中欧的森林遭受了由气候变化引起的直接后果—千旱.所有这些森林都有着悠久的经营历史,重新种植受损森林的责任落到了土地所有者的身上.因此,土地所有者和政府正在寻找适合在树木灭绝地区重新种植的树种.事实上,很好的了解物种的抗旱性对当前树木的重新种植非常关键.我们在41种原产于或引进于中欧的木本树种中确定了一个被广泛认可的叶片耐旱特性(在充分水合作用下膨压损失点的叶片水势,即;πtlp).采用渗透快速评价法测定了暴露于阳光下的叶片在充分水合作用下的渗透势(πσsm),并将其转化为πtlp.本地种的平均πtlp为-2.33±0.33 MPa.引进树种Aesculus hypocastania的πtlp为-1.70 ±0.11 MPa.引进树种Pseudotsuga menzesii的πtlp值为-3.02±0.14MPa,耐旱性最强.绝对值较低的负值;πtlp表示抗旱性较低,绝对值较高的负值πtlp表示抗旱性较高.例如,两种本地物种Illex aquifolium和Alnus glustinosa是潮湿生境的自然伴生物种,其πtlp值分别为-1.75 ±0.02 MPa和-1.76 ±0.03 MPa.“,”The last years,Central European forests have suffered from drought as a direct consequence of climate change.All these forests have a long management history and it lies in the landowner's responsibility to replant damaged forests.Hence,landowners and the government are searching currently for species suitable to replant in areas affected by tree die-offs.It is a matter of fact that good knowledge of drought resistance of species is a critical measure for the current replanting efforts.We determined a widely recognized trait for leaf drought tolerance(leaf water potential at turgor loss point at full hydration,πtlP)in 41 woody species native or introduced in Central Europe.The osmometric rapid assessment method was used to measure the leaf osmotic potential at full hydration(nosm)of sun-exposed leaves and converted to πtlp.Mean πtlp of the native species was-2.33 ± 0.33 MPa.The less negative πtlp was found in the introduced species Aesculus hypocastania and was at-1.70 ±0.11 MPa.The most negative πtlp,and thus the potentially highest drought tolerance,were found in the introduced species Pseudotsuga menzesii and was at-3.02 ± 0.14 MPa.High or less negative πtlp is associated with lower drought tolerance,whereas low or more negative πtlp stands for higher resistance to drought stress.For example,the two native species//lex aquifolium and Alnus glustinosa are species naturally associated with moist habitats and are characterized by the least negative πtlp of-1.75 ± 0.02 and-1.76 ± 0.03 MPa,respectively.