Knowledge Resource Center for Ecological Environment in Arid Area
| 霸王与沙拐枣植物种子风力传播风洞模拟研究 | |
| 其他题名 | Wind tunnel simulations for seed dispersal by wind in Zygophyllum xanthoxylon and Calligonum species |
| 朱金雷 | |
| 出版年 | 2015 |
| 学位类型 | 博士 |
| 导师 | 刘志民 |
| 学位授予单位 | 中国科学院大学 |
| 中文摘要 | 种子传播是重要的植物生活史过程。种子风力传播在草原及荒漠生态系统极其普遍。种子初始风力传播过程主要由何种因素决定？物种属性和景观结构如何相互作用以决定种子二次传播能力？种子传播方式赋予植物何种适应策略？这些问题是种子风力传播研究领域的核心，但是，目前尚非常缺乏综合考虑各种因素(尤其是传播体形态属性)开展的实证研究。有鉴于此，本研究以霸王5种异型性传播体及5种沙拐枣植物传播体为研究对象，借助大尺寸环境风洞，对种子初始与二次风力传播过程进行模拟实验，揭示环境因素、母株特征与传播体属性对初始传播的影响，确定下垫面特征与传播体属性对二次风力传播过程的影响，阐释初始与二次风力传播过程间的相互关系，判断传播过程所赋予植物的适应对策。主要结论如下： 1) 影响种子初始风力传播距离的因子依次为风速、种子释放高度与传播体沉降速度；在风力条件(包括风速与种子释放高度)相同时，影响种子初始风力传播距离的因子依次为传播体翼负荷、沉降速度与形状系数。 2) 传播体起动风速受下垫面类型影响，下垫面粗糙度愈大，传播体起动风速愈大；在下垫面类型相同时，影响传播体起动风速的因子依次为翼负荷与形状系数。 3) 对霸王5种异型性传播体及5种沙拐枣植物传播体的初始与二次风力传播研究表明：初始与二次风力传播能力间是否存在权衡关系与下垫面属性有关，下垫面粗糙度小时存在权衡关系，粗糙度大不存在权衡关系。仅对霸王5种异型性传播体间的初始与二次风力传播研究表明：初始与二次风力传播存在权衡关系，权衡关系与下垫面类型无关，但与风力条件（包括风速与种子释放高度）阈值有关。因此，传播体初始与二次风力传播之间的权衡关系存在但不是普遍现象。 4) 通过比较种子初始与二次风力传播能力对植物适应策略进行了初步判断。依据初始与二次传播能力间的关系划分出4种类型：初始传播与二次传播均弱如红皮沙拐枣(传播体具刺+翼)，初始传播强但二次传播弱如具二翼的霸王传播体，初始传播弱但二次传播强如乔木状沙拐枣(传播体具刺)，初始传播与二次传播均处于中间水平如具四翼的霸王传播体。依据传播距离划分出2种类型：远距离传播策略如具三翼的霸王传播体，抗远距离传播策略如红皮沙拐枣。综合考虑种子传播能力与萌发属性划分出2种类型：传播距离远且种子萌发率高的拓殖型适应策略如具二翼的霸王传播体，传播距离近且种子萌发率低的竞争型适应策略如白皮沙拐枣(具翼)。 |
| 英文摘要 | Seed dispersal is a vital process in plant life history. Seed dispersal by wind is one of the most important dispersal modes in the grassland and desert ecosystems. What are the determinants of the primary seed dispersal process? How do species traits and landscape configuration interact to determine secondary seed dispersal? What adaptive strategies to plants do different wind dispersal patterns confer? These questions are major challenges in the research field of seed dispersal by wind, however, there have been rare empirical studies concerning various factors (especially diaspore morphology attributes). In this study we tested the both primary and secondary dispersal capacity of five distinct morphologies of winged diaspores in heterocarpous species Zygophyllum xanthoxylon (Zygophyllaceae) and diaspores in 5 Calligonum species in a wind tunnel. The influences of environmental factors, parent plant traits and diaspore attributes to primary seed dispersal distance were quantitatively evaluated, and the effects of substrate and diaspore morphology on secondary seed dispersal process were determined. The interactive relationships between primary and secondary seed dispersal processes were analyzed, and the adaptive strategies conferred to plants by the seed dispersal by wind were estimated. The major conclusions are as follows: 1) The important determinants to primary seed dispersal distances are wind speed, release height and terminal velocity in turn. Under a certain condition of seed dispersal by wind, i.e. when wind speed and release height are settled, the important determinants to primary seed dispersal distances are diaspore wing loading, terminal velocity and shape index in turn. 2) The lift-off velocity of diaspore is affected by substrate type. The lift-off velocity is much bigger on substrate with higher roughness than on substrate with lower roughness. On the same type of substrate, the important determinants to lift-off velocity are diaspore wing loading and shape index in turn. 3) For the all 5 morphologies of diaspores in Z. xanthoxylon and diaspores in 5 Calligonum species, whether there exists a trade-off between primary and secondary seed dispersal is determined by the substrate roughness. There exists a trade-off only if the roughness is relative low. For the 5 morphologies of diaspores in Z. xanthoxylon, the trade-off between the primary and secondary seed dispersal is not relevant with substrate type but with wind conditions (the product of wind speed and release height). Therefore, there are, but not always, a trade-off between the primary and secondary seed dispersal. 4) Four adaptive strategies are distinguished according to the relationships between primary and secondary dispersal capacities: species with both low primary and secondary dispersal capacities such as C. rubicundum (diaspore with spine + wing), species with high primary but low secondary dispersal capacities such as disc diaspore in Z. xanthoxylon, species with low primary but high secondary dispersal capacities such as C. arborescens (diaspore with spine), and species with both moderate primary and secondary dispersal capacities such as four-winged diaspores in Z. xanthoxylon. Two adaptive strategies are distinguished according to seed dispersal distance: telechoric species such as three-winged diaspores in Z. xanthoxylon, and antitelechoric species such as C. leucocladum. Two adaptive strategies are distinguished according to the combination of seed dispersal and seed germination: colonization strategy represented by species with far dispersal distance and high germination ratio such as disc diaspores in Z. xanthoxylon, and competition strategy represented by species with low dispersal distance and low germination ratio such as C. leucocladum. |
| 中文关键词 | 播体形态 ; 附属物 ; 沉降速度 ; 植物适应对策 ; 风洞模拟实验 |
| 英文关键词 | diaspore morphology appendage terminal velocity plant adaptation strategy wind tunnel simulation experiment |
| 语种 | 中文 |
| 国家 | 中国 |
| 来源学科分类 | 生态学 |
| 来源机构 | 中国科学院沈阳应用生态研究所 |
| 资源类型 | 学位论文 |
| 条目标识符 | http://119.78.100.177/qdio/handle/2XILL650/287572 |
| 推荐引用方式 GB/T 7714 | 朱金雷. 霸王与沙拐枣植物种子风力传播风洞模拟研究[D]. 中国科学院大学,2015. |
| 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 |
| [朱金雷]的文章 |
| 百度学术 |
| 百度学术中相似的文章 |
| [朱金雷]的文章 |
| 必应学术 |
| 必应学术中相似的文章 |
| [朱金雷]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。
