额济纳绿洲不同树龄胡杨狭叶和阔叶耐旱特征

应用压力室技术对胡杨幼苗、幼树和成熟胡杨的狭叶和阔叶测定，绘制PV曲线并利用相关公式计算不同树龄胡杨狭叶和阔叶的水分参数，同时结合角质层蒸腾和气孔蒸腾测定结果研究胡杨狭叶和阔叶耐旱特征。研究结果表明：胡杨阔叶的耐早性强于狭叶，二者的耐旱方式存在差异，阔叶渗透物质含量高，忍耐低渗透势的能力强；狭叶主要通过高弹性的细胞壁维持膨压，其忍耐低渗透势的能力不及阔叶。成熟胡杨无论狭叶还是阔叶主要的水分散失形式是气孔蒸腾，体内的水分平衡主要通过气孔进行调节。

Drought Tolerance Characteristics of Populus euphratica Narrowleaf and Broadleaf at Different Ages in Ejina

Drought tolerance characteristics of Populus euphratica broadleaf and narrowleaf have been studied in seedlings, young trees and mature trees measured with the pressure chamber technique, PV curve is drawn, and combined with the relevant formulas, water parameters of Populus euphratica broadleaf and narrowleaf at different tree ages have been calculated. The results show： the tolerance of Populus euphratica broadleaf can put up with more drought than narrowleaf. There are differences ways for drought tolerance. Broadleaf osmotic material content is high and is able to tolerate low osmotic potential. Narrowleaf cell wall is highly flexible turgor and is able to tolerate low osmotic potential less than broadleaf. Broadleaf and narrowleaf evaporate mainly by stomatal transpiration and water balance inside trees can be adjusted by stomata opened or closed in mature Populus euphratica.