白龙江干旱河谷常见灌木树种叶片持水性能

目的]以白龙江干旱河谷20种常见灌木树种为材料,研究其叶片形态与持水之间的关系,更好地了解其叶片持水能力,为灌木树种在干旱河谷区的生态适应、优化群落结构提供科学依据,更好地发挥其水土保持、防风固沙的作用.方法]通过简单的室内浸泡法对叶片持水状况进行测定,测定出每种树种叶片持水量的相关数据及叶片的形态特征,通过因子分...

Water retention properties of leaves of common shrub trees in the arid valley of Bailong river

【Objective】Taking Bailong river valley 20 common drought shrub tree species as the material,in order to study the leaf morphology and the relationship between the moisture,water-holding capacity,better able to understand the blade for shrub tree species in the arid valley area will provide a scientific basis for ecological adaptation,optimize the community structure,better play the role of water and soil conservation,windbreak and sand-fixation.【Method】The water holding capacity of leaves was determined by simple indoor soaking method,and the relevant data of the water holding capacity of leaves of each tree species and the morphological characteristics of leaves were determined.The water holding capacity and leaf shape indexes were analyzed by factor analysis,redundancy analysis and cluster analysis.【Result】Leaves the water holdup is largest natural moisture rate is 2.59 to 5.34 times that of leaf water holding capacity of different shrub tree species increases with the increase of immersion time,a logarithmic relation,the increase of the water rate and water absorption time is reduced,there is a significant power function relationship,in the initial period of flooding 0.25 h,bibulous rate is the largest,Berchemia sinica is the largest,Rhamnus davurica is the minimum;FA analysis was made on the morphological characteristics and water holding capacity of shrub leaves,reflecting the three principal components,and the comprehensive score of water holding capacity of shrub leaves was calculated,with the highest score being 1.88.Through factor analysis,redundancy analysis and cluster analysis,the dry valley of Bailong river is divided into three water holding groups.【Conclusion】The natural water content of leaves of different shrub species is not equal to the maximum water holding rate.The water holding trend of the leaves is the same,and the time point when the water holding reaches saturation is divided into three parts:8,12 and 24 h.With the extension of water holding time,the leaves absorb more water,and the plant leaf cells expand to reach the maximum water holding capacity,the water holding rate gradually slows down,the leaves may not have the ability to continue to hold water or the water holding capacity is weakened.According to FA analysis,the three principal components obtained are related to leaf size,leaf quality and villi condition.The Bailong river valley of 20 drought shrub tree species water-holding performance can be divided into three categories according to the comprehensive water function group:PFGⅠhigh moisture function group of two,PFGⅡin hold water in the group of eight,PFGⅢwater-holding capacity low group of ten.