Knowledge Resource Center for Ecological Environment in Arid Area
| 不同潜水埋深条件下多年生植物幼苗生长特性和根系分布特征研究 | |
| 其他题名 | Study on characteristics of plant growth and root distribution of perennial plant seedlings under different groundwater table depths |
| 彭守兰 | |
| 出版年 | 2013 |
| 学位类型 | 硕士 |
| 导师 | 曾凡江 |
| 学位授予单位 | 中国科学院大学 |
| 中文摘要 | 疏叶骆驼刺（Alhagi sparsifolia Shap.）和多枝柽柳（Tamarix ramosissima Ledeb.）是塔克拉玛干沙漠南缘的优势植物种，在策勒沙漠-绿洲过渡带上有一定面积的分布，其具有耐干旱、抗盐碱的生理生态适应特性，成为当地防风固沙的重要植物。近年来，随着绿洲面积的扩大和过渡带面积缩减的同时，地下水位逐年下降，导致绿洲内部及外围的多年生植被群落退化。因此了解不同潜水埋深条件下植物的生长特性和根系分布特征成为塔克拉玛干沙漠南缘植被恢复过程中重要的科学问题。本研究依托策勒国家站，以一年生幼苗疏叶骆驼刺和多枝柽柳幼苗为实验对象，以幼苗根系生长和分布对不同潜水埋深响应特征为主要研究内容，通过建立半地下室实验池和人工控制地下潜水埋深的方法，研究植物生长特性和根系分布特征对潜水埋深变化的响应，在2012年植物生长季内（7-10月）进行实验。研究结果对于揭示干旱区多年生植物对干旱环境的适应有重要生态学意义，同时为研究区退化植被修复提供理论参考。研究结果包括以下几个方面： （1）植物生长方面：株高和冠幅的生长速率随着潜水埋深的增加而先增加后减小，且均在120cm潜水埋深条件下生长最快，220cm潜水埋深条件下生长最慢；但地上生长策略不同，骆驼刺冠幅生长先于株高生长，属于横向生长类型；而柽柳则表现为株高生长先于冠幅生长，属于纵向生长类型。 （2）根系生长方面：根系生长速率随潜水埋深和时间的变化有所差异，生长后期（8-9月）根系生长速率高于生长前期（7-8月），生长前期骆驼刺和柽柳根系生长速率在220cm潜水埋深条件下最大，而生长后期在180cm潜水埋深条件下幼苗根系生长速率最大。整个生长季内骆驼刺和柽柳的最大根系生长速率分别为2.52cm?d-1、3.39cm?d-1，其根系到达220cm潜水埋深所需的时间分别为123d、118d。 （3）生物量分配方面：植株生物量随潜水埋深的增加而先增加后减小，根冠比随潜水埋深的增加而增加。潜水埋深较小条件下，柽柳生物量积累远大于骆驼刺；当潜水埋深增加到220cm时，骆驼刺生物量与柽柳相差不大。骆驼刺根冠比大于柽柳，且随着潜水埋深的增加，根冠比快速增加，表明骆驼刺对环境的变化，特别是土壤水分条件变化的响应较为敏感。随着潜水埋深的增加，根系直径小于3mm的根系生物量及比重增加，直径大于3mm的根系生物量及比重减小；柽柳不同直径级别的根系生物量均大于骆驼刺。 （4）根系垂直分布方面：骆驼刺和柽柳根系生物量和表面积均随土壤深度的增加而减小，在垂直剖面上呈倒金字塔状分布；不同直径根系在土壤中的垂直分布有所差异，随着潜水埋深的增加，直径在3-5mm 根系集中分布在表层，在深层土壤中多为根系直径小于3mm的根系。直径小于1mm的根系在土壤中的分布均匀，并呈现缓慢增加后再减小的趋势。 |
| 英文摘要 | Alhagi sparsifolia Shap. and Tamarix ramosissima Ledeb. are the dominant species at the southern margin of the Taklimakan desert and distribute in the desert-oasis transitional zone of Cele with large areas. Two plant species are both resistant to drought and salt and to be the important plant for preventing from wind storms and fastening sand. Recently, expansion of oasis area and decline of groundwater level have resulted in large areas of vegetation degradations inside and outside the oasis regions. For this reason, understanding growth and root distribution of vegetation in different phreatic water levels is significant in vegetation restoration of southern margin of the Taklimakan desert. Supported by Cele National Station, this study took the annual seedlings of A. sparsifolia and T. ramosissima as the experimental materials, in order to analyze the responses of growth and root distribution of seedlings under different groundwater table treatments. Based on the establishment of experimental pool and water level control, this study took experiments in the growing seasons of vegetation (from July to October) in 2012. The results of this study help to reflect the adaptation of perennial plants to drought environment and provide the references for vegetation restoration in the study region. The following results were attained. （1）On plant growth: With the increase of phreatic water level, the height and canopy growth rate of two seedlings both firstly increased and then decreased. The canopy growth of two seedlings was the fastest in the phreatic level of 120cm and the slowest in the phreatic level of 220 cm. Two seedlings have different growth strategies. A. sparsifolia belongs to the lateral growth; the canopy growth of its seedling is in advance of its height growth. T. ramosissima belongs to the vertical growth; its height growth is in advance of its canopy growth. （2）On root growth: The root growth rate of two seedlings is increasingly higher with the increase of phreatic water level; the one of late growth stage (July and August) is higher than that of earlier growth stage (August and September). The root growth rate of A. sparsifolia and T. ramosissima reaches the maximum under the phreatic level of 220cm at earlier growth stage, while under 180cm depth the root growth rate of two seedlings reach maximum at the late growth stage. The maximum root growth rate of A. sparsifolia and T. ramosissima are 2.52cm?d-1 and 3.39cm?d-1 respectively in the whole growing season. There need to take 123 d and 118 d for the roots of two seedlings reaching the diving depth of 220 cm. （3）On biomass distribution: The biomass of two seedlings increase and then decrease with the increase of phreatic level, and Root-shoot ratio increases with the increase of diving depth. Under smaller Diving depth conditions, the biomass accumulation of T. ramosissima is much larger than A. sparsifolia; when diving depth is increased to 220cm; there is little difference with the biomass between them. Root-shoot ratio of A. sparsifolia is larger than T. ramosissima, and increase rapidly with the increase of phreatic level. It indicates that when environment changes, especially soil moisture conditions changes, the response of A. sparsifolia for the changes is more sensitive than T. ramosissima. With the increase of phreatic level, root biomass and proportion with root diameter less than 3mm are increased, and root biomass and proportion with root diameter greater than 3mm are decreases. A different diameter level of root biomass of T. ramosissima is greater than A. sparsifolia. (4)On root vertical distribution: with the increase of phreatic level, the root biomass and root superficial area of two seedlings all decrease and present an inverted pyramid distribution on the vertical section. There exist differences in the vertical distribution of roots with different diameters. With the increase of phreatic level, the roots with the diameter of 3-5 mm distribute on the surface soil, and the roots with the diameter below 3 mm usually distribute in the deeper soil layers. The roots with the diameter below 1 mm distribute evenly in the soil and present a trend of increasing gradually and then decreasing. |
| 中文关键词 | 骆驼刺 ; 柽柳 ; 生物量分配 ; 根系生长 ; 根系分布 ; 潜水埋深 |
| 英文关键词 | Alhagi sparsifolia Shap. Tamarix ramosissima Ledeb. biomass allocation root growth root distribution groundwater table depth |
| 语种 | 中文 |
| 国家 | 中国 |
| 来源学科分类 | 环境工程 |
| 来源机构 | 中国科学院新疆生态与地理研究所 |
| 资源类型 | 学位论文 |
| 条目标识符 | http://119.78.100.177/qdio/handle/2XILL650/287286 |
| 推荐引用方式 GB/T 7714 | 彭守兰. 不同潜水埋深条件下多年生植物幼苗生长特性和根系分布特征研究[D]. 中国科学院大学,2013. |
| 条目包含的文件 | 条目无相关文件。 | |||||
| 个性服务 |
| 推荐该条目 |
| 保存到收藏夹 |
| 导出为Endnote文件 |
| 谷歌学术 |
| 谷歌学术中相似的文章 |
| [彭守兰]的文章 |
| 百度学术 |
| 百度学术中相似的文章 |
| [彭守兰]的文章 |
| 必应学术 |
| 必应学术中相似的文章 |
| [彭守兰]的文章 |
| 相关权益政策 |
| 暂无数据 |
| 收藏/分享 |
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。
