KMS XINJIANG INSTITUTE OF ECOLOGY AND GEOGRAPHY，CAS
| 疏叶骆驼刺叶形态和水分生理对光强的响应 | |
| 马天光 | |
| Subtype | 硕士 |
| Thesis Advisor | 李向义 |
| 2018-06-01 | |
| Degree Grantor | 中国科学院大学 |
| Place of Conferral | 新疆乌鲁木齐 |
| Degree Discipline | 理学硕士 |
| Keyword | 疏叶骆驼刺 光强 叶形态 水分生理 Alhagi sparsifolia Shap. Light intensity Leaf morphology Water physiology |
| Abstract | 塔克拉玛干沙漠南缘属于典型内陆暖温带荒漠气候。 夏季炎热， 干旱少雨，光热充足， 水分亏值较大。 该区域荒漠植物通常遭受强光、 干旱、 高温、 风沙等环境的多重胁迫。 疏叶骆驼刺（Alhagi sparsifolia Shap.） 是该区域重要的植被群落， 对防风固沙、 维护绿洲脆弱的生态环境具有重要作用。 因此， 研究极端强光、干旱等环境条件下疏叶骆驼刺生理特征对生境胁迫的适应机制和策略， 对于退化植被的修复具有重要意义。本研究以极端干旱区自然环境中生长的疏叶骆驼刺为研究对象， 通过测定疏叶骆驼刺在不同光强条件下的叶形态和水分生理指标， 研究光强对疏叶骆驼刺叶形态和水分生理的影响； 以期揭示疏叶骆驼刺叶形态和水分生理对光强变化的响应特征， 为疏叶骆驼刺的植被修复和生态保护以及种群扩大提供科学依据。 主要结果如下：1. 光强的改变对疏叶骆驼刺叶形态产生了明显的影响。 随着光强的减弱，疏叶骆驼刺叶性状的变化特征趋于光能利用效率的提高， 叶厚和比叶质量显著变小（P<0.05） ， 单叶面积和比叶面积显著变大（P<0.05） ； 同时， 疏叶骆驼刺地上部分各器官的生物量分配格局变化也趋于增加光合器官叶的生物量投入， 减少生殖器官果和刺的生物量投入（P<0.05） ； 并且随着光强的减弱， 可能导致疏叶骆驼刺的繁殖方式发生变化， 有性繁殖能力受到抑制， 克隆繁殖能力得到进一步的增强。2. 光强的改变对疏叶骆驼刺水分生理产生了明显的影响。 随着光强的减弱，疏叶骆驼刺水分生理特征表现为： 叶片相对含水量和水势变大（P<0.05） ， 气孔导度和蒸腾速率减小（P<0.05） ； 同时， 失水速率、 零膨压点渗透势、 最大膨压渗透势、 零膨压点相对含水量、 最大细胞弹性模量和饱和枝条含水量与枝条干物质之比变大（P<0.05） ， 水分利用效率和束缚水含量变小（P<0.05） 。 因此， 光强的减弱一方面缓解了疏叶骆驼刺生境的强光和干旱胁迫， 植株水分消耗减小，水分亏缺恢复能力增强； 但同时也减小了植株的水分利用效率、 组织保水能力以及叶片对脱水的忍耐能力和保持膨压的能力， 进而降低了植株的抗旱能力。3. 研究表明光强变化条件下疏叶骆驼刺叶性状的变化和其水分生理状况的变化有着极显著的相关性。疏叶骆驼刺叶片性状变化是影响其水分生理参数变化的主要因素。 |
| Other Abstract | The southern edge of the Taklamakan Desert is featured by a typical continentaltemperate desert climate, with extreme hot and dry environment in summer as well aslow annual precipitation, and radiation resource and heat energy are relatively rich.Desert plants in this region are often subjected to multiple stresses of drought, hightemperatures, strong light, and wind and sand. Alhagi sparsifolia Shap. speciesrepresents an important vegetation community on the southern edge of theTaklamakan Desert, which plays an important role in mitigating effects to wind andsand erosion and in maintaining the stability of fragile ecological environment. It is,therefore, important to study underlying morphological and physiological mechanismsof A. sparsifolia in response to environmental stress conditions that they commonlyencounter such as extreme light intensity and drought. In this study, A. sparsifolia inthe natural environment of extreme arid regions were studied. The effects of lightintensity on leaf morphology and water physiology of A. sparsifolia by studied bymeasuring leaf morphology and water physiological parameters under different lightintensity conditions. The objectives of this study are to reveal the responsecharacteristics of light leaf morphology and water physiology to changes in lightintensity and provide scientific basis for the restoration of vegetation and ecologicalprotection and population expansion of A. sparsifolia.Our results showed that:1. Changes of grown light intensity have significant effects on leaf morphologyof A. sparsifolia. With decline of the light intensity, the leaf traits tended to increasethe traits of utilization efficiency of light energy. Leaf thickness and leaf mass per unitarea were significantly smaller at lower light environment (P<0.05), and the singleleaf area and specific leaf area therefore increased significantly (P<0.05). At the sametime, the changes in the biomass allocation patterns of the aboveground parts of A.sparsifolia also tend to increase the biomass input of the photosynthetic apparatus(P<0.05) and reduce the biomass input of the genital organs and thorns (P<0.05); andwith the weakening of the light intensity, it may lead to changes in the reproduction ofA. sparsifolia, the sexual reproduction ability is inhibited, and the clonal reproductionability is further enhanced.2. Changes of light intensity significantly affected leaf physiology of A.sparsifolia. Leaf relative water content and water potential became larger (P<0.05),and stomatal conductance and transpiration rate decreased (P<0.05) in low lightintensity group. At the same time, the leaf water loss rate, ψπ0, ψπ100, RWC0, εmax andWCsat became larger (P<0.05), water use efficiency and Va became smaller (P<0.05).Therefore, the weakening of the light intensity on the one hand alleviates the stronglight and drought stress of the habitat of A. sparsifolia, and the water consumption ofthe plant decreases, and the water deficit recovery ability increases; At the same time,it also reduces the water use efficiency of the plants, the ability to maintain water intissues, the ability to withstand dehydration, and the ability to maintain turgorpressure, thereby reducing the plant's ability to fight drought.3. .This study shows that there is a very significant correlation between changesin leaf traits and changes in their water physiological conditions of A. Sparsifoliaunder light intensity changes. In addition, the change of leaf traits in A. Sparsifolia isthe main factor affecting the change of its physiological parameters. |
| Subject Area | 生态学 |
| Language | 中文 |
| Document Type | 学位论文 |
| Identifier | http://ir.xjlas.org/handle/365004/14980 |
| Collection | 研究系统_荒漠环境研究室 |
| Affiliation | 中国科学院新疆生态与地理研究所 |
| First Author Affilication | 中国科学院新疆生态与地理研究所 |
| Recommended Citation GB/T 7714 | 马天光. 疏叶骆驼刺叶形态和水分生理对光强的响应[D]. 新疆乌鲁木齐. 中国科学院大学,2018. |
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