骆驼刺幼苗根系生长对不同水分条件的响应
文献类型：学位论文
| 作者 | 郭海峰 |
| 学位类别 | 硕士 |
| 答辩日期 | 2008 |
| 授予单位 | 中国科学院．新疆生态与地理研究所 |
| 导师 | 曾凡江，中国科学院新疆生态与地理研究所 |
| 关键词 | 骆驼刺幼苗 |
| 其他题名 | Root growth of Alhagi Spacifolia juveniles response to different water conditions |
| 中文摘要 | 研究植物根系生长、分布特征与土壤水分和地下水的关系对于揭示荒漠植物对干旱环境的适应有重要的生态学意义。在新疆塔克拉玛干沙漠南缘荒漠-绿洲过渡带上有一定面积的骆驼刺植被分布，它们不仅是当地重要的防风固沙植物，而且是当地重要的优质牧草。本研究以骆驼刺一年生幼苗为研究对象，以骆驼刺幼苗根系生长、分布对不同潜水埋深和不同地面灌溉响应特征为研究内容，在2007年植物生长期内（6月-10月），采用人工壕沟挖掘法系统研究骆驼刺幼苗根系生态适应性。在试验观测、测定分析和数据处理的基础上，得出如下结论： (1) 根系垂直生长方面：增加垂直根扎根深度和垂直根生长速度是骆驼刺幼苗适应干旱的主要表现。土壤质量含水率在3%-9%之间时，垂直根生长较快；在13%-20%之间时，根系向下生长缓慢；在30%左右时，垂直根生长停止达到临界值。 (2) 根系形态方面：根系主要由水平根和垂直根组成，根系形态的可塑性是骆驼刺幼苗获取水分适应干旱环境的重要策略之一。水分条件好时，它们大量拓展水平根并产生分蘖植株到地面竞争光照资源，水分条件差时垂直根系发达，向深层土壤拓展资源空间。 (3) 根系分布方面：潜水埋深的减小和地面灌溉的增加都会导致根系分布的浅表层化。根系生物量、根系表面积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。增加根系生物量在深层土壤的分布是骆驼刺幼苗应对土壤干旱的方式之一。 (4) 在根冠比方面：增加根冠比是骆驼刺幼苗适应干旱的有效策略。根冠比随潜水埋深的增加和地面灌溉的减少而增加，且生长季后期大于初期。它们在生长初期把更多生物量分配到地面用以竞争光照资源，生长后期把更多生物量分配到根系用以来年生长能量的蓄积。 (5) 根/冠生长动态方面：骆驼刺幼苗能随水分改变而自我调节生长比例来适应环境。不同水分条件下的其根、冠生长均属于典型的异速生长关系；地上和地下生物量形成过程符合Logistic慢-快-慢的S型生长曲线，总生物量随着土壤干旱程度的增加而降低。Study on root growth and distribution response to different soil water and groundwater table has a significant ecological meaning on understanding the desert plants adaptation to arid environments. There are some Alhagi.sparsifolia grow in the oasis-desert transition in south fringe of Taklamakan desert in Xinjiang. They are not only a good sandstorm defending plants, but also a high quality pasturage. This study take one year old Alhagi.sparsifolia juveniles as study objects, study how its root growth and distrbution response to different groundwater table and different surface irrigations. In growing period June to October in 2007, We use trench methods systemicly study ecological adaptation of its root system. Base on observervition, analyse and data processing, conclusions are as fllowing: (1) On growth of vertical root: Increase the rooting depths and vertical rooting speed is the mainly performance of it adaptation to arid environment.Water content in 3% to 9% is a sensitive value for its root growth, 13% to 20% is an insensitive value for it, when get to 30% its root stop growing. (2) On root architecture: Its root system composed with vertical roots and horizontal roots. Plasticity of root architecture is a very important strategy for them to obtaining soil water and adaptation the arid environment. When there is a good water condition in soil, they develop horizontal root system and tiller new individuals to compete sunshine. If water limited, they develop vertical root to exploit the resources in deeper soil layer. (3) On root distribution: Groundwater table shorter and surface irrigation reduce both will lead root distribution in the upper soil layer. Root biomass and root surface area distribution like a headstand pyramid in soil profiles, which decrease with soil depth increase. Increase the percentage of root biomass in deeper soil layer is a way of it response to water decrease. (4) On root shoot ratio: Increase root shoot ratio also is an efficiency strategy to adaptation soil water shortage. Water shortage make it puts more biomass into root system. At the beginning of growth period it puts more biomass into shoot to competition sunshine, in the end of growth period it puts much more biomass into root preparing for the coming year’s growth. (5) On root-shoot dynamic: It changes the growth proportion to adaptation the environment as soil water changing. It is an allometry relationship between shoot and root in different water treatments. Shoot and root biomass formulation accord with Logistic S grow curve. Total biomass decrease whit water shortage increase. |
| 学科主题 | 植物生理学 |
| 语种 | 中文 |
| 公开日期 | 2010-11-12 |
| 页码 | 共52页 |
| 源URL | [http://ir.xjlas.org/handle/365004/8012]  |
| 专题 | 新疆生态与地理研究所_中国科学院新疆生态与地理研究所(2010年以前数据) |
| 推荐引用方式 GB/T 7714 | 郭海峰. 骆驼刺幼苗根系生长对不同水分条件的响应[D]. 中国科学院．新疆生态与地理研究所. 2008. |
入库方式： OAI收割
来源：新疆生态与地理研究所
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