【作者】 张海敏；

【导师】 王林和； 刘美珍；

【作者基本信息】 内蒙古农业大学 ， 水土保持与荒漠化防治， 2010， 硕士

【摘要】 本文以北京植物园里引种栽培的植物水杉(Metasequoia glyptostroboides H.)、银杏(Ginkgo biloba L.)、雪松(Cedrus deodara G.)、毛白杨(Populus tomentosa C.)、家榆(Ulmus pumila L.)、大果榆(Ulums macrocarpa H.)、垂柳(Salix babylonica L.)和紫藤(Wisteria sinensis S.)为研究对象,通过PV曲线、水力导度和解剖学的方法对8种植物的叶片水分参数、气孔特征、茎的导水特性和木质部解剖结构进行对比分析研究。结果表明:1.从PV曲线上获得的叶片水分参数看,同一树种不同月份水分特征有着明显的差异。不同类型植物种的变化规律不一致,这与树木对环境条件(光照、水分、气温等)的适应性及其滞后作用有关。裸子植物在速生期(7月-9月)都表现出较高的饱和渗透势(ψs)和失膨点水势(ψw)值;旱生乔木毛白杨则在速生期表现较低的ψs和ψw值。其他物种变化规律均不明显。2.通过对叶片水分参数的均值以及各树种气孔的比较研究,可以将8种植物分为4种不同生态类型:(1)较高ψs和ψw,较低气孔密度和较小气孔的裸子植物水杉、银杏和雪松;(2)较低ψs和ψw,较大的细胞弹性模数,较低气孔密度和较小气孔的旱生乔木毛白杨;(3)较高ψs和ψw,较高气孔密度和较大气孔的家榆、大果榆和垂柳;(4)较低ψs和ψw,较高气孔密度和较小气孔的藤本植物紫藤。3.8个树种茎的导水特性有显著的差异,裸子植物的管胞密度大,但导水性最差,而藤本植物紫藤导管直径最大,表现出最强的导水特性。旱生、中旱生乔木位于二者之间。4.树种胡伯尔值与其他三个水力结构参数呈负相关,说明植物在水分运输和扩散方面要与自身的结构和功能保持对应性和协调一致性。导管或管胞的直径与最大导水率、比导率和叶比导率呈现正相关,说明直径较大的导管更利于水分的传输。更多还原

【Abstract】 The purposes of the thesis were to study the leaf water traits, stomatal characteristics,xylem anatomy and hydraulic conductivity and compare differences in water transportation of eight species combination of these parameters using PV curve, hydraulic conductivity and anatomy.The species, Metasequoia glyptostroboides、Ginkgo biloba、Cedrus deodara、Populus tomentosa、Ulmus pumila、Ulums macrocarpa、Salix babylonica and Wisteria sinensis were chosen as materials. These plants were introduced into Beijing Botanical Garden from their original habitats of China in 1960s’and have cultivated for almost 50 years. So the variance in water transportation mainly depend on their genetically differences, rather than the environment factors. The main results were as follows:1. Water parameters from the PV curve showed the variations during growth stage in the same species, and the inconsistent changes in different species. The trends related to adaptability and hysteresis of different species on the environmental conditions (light, moisture, temperature, etc.) Gymnosperms have shown a high saturation osmotic potential (ψs) and water potential at turgor loss point (ψw) in the fast-growing period (July-september). In contrast, the lower values ofψs andψw were recorded in Populus. No significant variation of other species.2. Eight kinds of plants will be divided into four different ecological types based on the analysis of leaf water parameters and stomatal characteristics of each species: (1)Metasequoia glyptostroboides、Ginkgo biloba and Cedrus deodara of gymnosperms showed higher values inψs andψw, lower stomatal density and smaller stoma;(2)Populus of xerophytic trees was lowerψs andψw, larger cell elastic modulus, lower stomatal density and smaller stoma;(3)Ulmus pumila、Ulums macrocarpa and Salix babylonica had higherψs andψw, greater stomatal density and larger stoma;(4)Wisteria sinensis of liana displayed lowerψs andψw, higher stomatal density and smaller stoma.3. Hydraulic conductivity of stem showed significant differences in eight species. Wisteria sinensis of liana had the largest conduit diameter and the strongest hydraulic conductivity, while the gymnosperms have the largest tracheid density, but the worst hydraulic conductivity among eight species. Hydraulic conductivity of other species fluctuated between the types.4. Huber value and hydraulic architecture parameters of the other three was found to be negative correlation, which indicated that maintaining coordination and coherence of structure and function in water transportation and disperse of plants. Diameter of conduit or tracheid was positively correlated with maximum hydraulic conductivity, specific conductivity and leaf specific conductivity. It suggested that the larger diameter of conduit was helpful of water transportation.更多还原