【作者】 李彦瑾；

【导师】 赵忠；

【作者基本信息】 西北农林科技大学 ， 森林培育， 2008， 硕士

【摘要】 通过盆栽控水的方法,对6种旱生灌木:柠条锦鸡儿(毛条Caragana korshinskii )、沙木蓼(Atraphaxis bracteata)、蒙古岩黄芪(杨柴Hedysarum mongolicum.)、细枝岩黄芪(花棒Hedysarum scoparium)、互叶醉鱼草(Buddleja alternifolia)、四翅滨藜(Atriplex canescens)进行生物量、水分利用效率、水分生理特征和PV参数进行研究,以期为毛乌素沙区植被恢复以及造林树种的选择提供一定的理论依据,试验结果表明:(1)在中度的干旱胁迫下,六种灌木的生长良好,生物量鲜重差异不显著。所以它们都能很好的适应中度干旱胁迫。重度干旱胁迫时,四翅滨藜合成的干物质的量都是最大,同时也有一个较大的水分蒸腾量,说明虽然重度干旱胁迫对它的生理活动造成了影响,但是其仍然能够顺利的完成同化物的合成,表现出对重度干旱胁迫的适应;醉鱼草,水分利用效率很低的;在重度干旱胁迫时,生物量大幅的下降,蒸腾耗水量也急剧减少,说明其不能适应重度的干旱胁迫;沙木蓼与毛条,各指标较为接近,但毛条的水分利用效率要稍高于沙木蓼;杨柴和花棒,能对水分胁迫迅速做出反应,提高水分利用效率,来相对增加干物质的积累,是对干旱胁迫适应的表现。(2)运用隶属函数值法综合分析PV参数和水分参数得出,中度干旱胁迫下,它们的抗旱性的由强到弱是:毛条>沙木蓼>四翅滨藜>杨柴>花棒>醉鱼草;而在重度干旱胁迫下,该顺序变为:沙木蓼>毛条>四翅滨藜>杨柴>花棒>醉鱼草。(3)植物的抗旱性是由多种抗旱途径或方式共同作用,在不同的生命时期采用不同的适应方式,四翅滨藜的适应方式既有高水势下延迟脱水,也有低水势忍耐脱水的能力;杨柴、花棒、毛条具有较低的蒸腾、较高的水分利用效率和低的清晨叶水势,是高水势下延迟脱水型植物及耐旱型植物;醉鱼草在中度胁迫时生长良好,但重度的干旱胁迫严重抑制生长,电导率增大,同化物合成急剧减少,明显不适应重度的干旱胁迫。更多还原

【Abstract】 Through potted cultivate we studied six shrubs’biomass, water use efficiency,water physical characters and PV parameters. And we hoped to provide a theoretical basis for Mu Us Sandland of vegetation restoration and the selection of species. The six shrubs are: Caragana korshinskii, Atraphaxis bracteata,Hedysarum mongolicum,Hedysaru-m scoparium, Buddleja alternifolia, and Atriplex canescens. And the results were as follows:1)Under moderate drought stress,six shrubs grow well, biomass fresh weight difference was not significant. So they can be well adapting to moderate drought stress. Under severe drought stress,Atyiplex canescens had the largest biomass and also had the largest water transpiration. It meant that although severe drought stress had an impact on physical activity, it is still able to successfully complete the synthesis of assimilation and had adaptation to the severe drought stress. Buddleja alternifolia, under severe drought stress had low water use efficiency, the biomass sharp declined and transpiration also reduced dramatically. The results showed that the Buddleja alternifolia can not adapt to severe drought stress. Atraphaxis bracteata and Caragana korshinskii had similar performance, while Caragana korshinskii had a higher water use efficiency than Atraphaxis bracteata, Hedysarum mongolicum and Hedysarum scoparium can adapt to drought stess. They can respond to water stress quickly, increase water use efficiency to improve the biomass.2)We can conclude from the analysis of the PV parameters and water parameters by subordinate function, In moderate drought stress, The order of drought-resistant ability is Caragana korshinskii > Atraphaxis bracteata>Atyiplex canescen>,Hedysarum mongolicum > Hedysarum scoparium.> Buddleja alternifolia. But in severe drought stress, The order is Atraphaxis bracteata>Caragana korshinskii >Atyiplex canescen>Hedysarum mongolicum > Hedysarum scoparium.> Buddleja alternifolia.3)Plants can against drought through a variety of ways working together, in different life periods use different ways, Atriplexcanescens adapt to the drought stress by high-water potential of delayed dehydration, while low water potential dehydration; Hedysarum mongolicum, Hedysarum scoparium, Caragana korshinskii had a low transpiration, high water use efficiency and low water potential of the early morning, belong to a high-water potential delay of dehydration and drought-resistant plants; Buddleja alternifolia in moderate stress grass grow well, however, the severe drought stress seriously inhibit growth, electrical conductivity increased dramatically, synthesis of assimilation reduced sharply, obviously not adapt to the severe drought stress.更多还原