Variability in Spore Dispersal and its Role in Kelp Population Dynamics

孢子传播的变异性及其在海带种群动态中的作用

• 批准号: 9614091
• 负责人: Peter Raimondi
• 金额: $ 5.94万
• 依托单位: University of California-Santa Cruz
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-01-01 至 2002-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9614091&HistoricalAwards=false
• 关键词: Variability; Spore; Dispersal; its; Role

9614091 RAIMONDI Kelp forests, dominant features of subtidal temperate reefs worldwide, undergo relatively frequent and unpredictable local extinctions and recolonizations. This project is a continuation of ongoing investigations of the causal mechanisms that allow for rapid forest recovery following widespread kelp loss. The objective of the project is to predict the frequency of occurrence and relative importance of the physical and biological conditions that promote extended spore dispersal in giant kelp (Macrocystis pyrifera) and determine: (1) the role of spore immigration rates in regulating the dynamics of local kelp populations and (2) the potential for limited dispersal to destabilize populations by reducing individual fitness. The research approach is to collect measurements of water motion simultaneously with measurements of spore release and dispersal from isolated plants over a wide range of physical and biological conditions. This information will be used to build an individual-based model that will predict effective spore dispersal within and away from a local population for varying conditions of water motion, plant fecundity, plant spacing, spore release, and population size. Predictions from the model will be tested using an experimental population of adult plants. The model will also be used to predict the frequency and spatial extent of self-fertilization under different conditions of water motion, plant fecundity, plant spacing, spore release, and population size. The effects of self-fertilization on individual fitness will be experimentally determined for all life stages. The information obtained from the project will apply generally to dispersal patterns of a large number of sessile marine organisms that release competent spores or larvae into nearshore waters. The general significance of this work is that it will provide much needed insight into the hydrodynamic conditions that promote extended propagule dispersal and the degree to which propagule immigration influenc es the dynamics of species perceived to have relatively closed populations. Additionally, the individual-based approach to this study will provide information on spore dispersal away from individual plants, which will be used to evaluate the costs of self-fertilization in giant kelp, a member of a dominant group of temperate marine algae whose life history and dispersal characteristics place them at high risk to the adverse effects of self-fertilization. ***

9614091 RAIMONDI 海带森林是全球潮间带温带珊瑚礁的主要特征，经历相对频繁且不可预测的局部灭绝和重新殖民。 该项目是对因果机制正在进行的调查的延续，这些机制允许在广泛的海带损失后快速恢复森林。该项目的目标是预测巨藻（Macrocystis Pyrifera）中促进孢子扩散的物理和生物条件的发生频率和相对重要性，并确定：（1）孢子迁移率在调节巨藻动态中的作用当地海带种群；(2) 有限的扩散可能会降低个体的适应性，从而破坏种群的稳定。研究方法是在广泛的物理和生物条件下，同时收集水运动的测量结果以及分离植物的孢子释放和扩散的测量结果。 这些信息将用于建立一个基于个体的模型，该模型将预测在不同的水运动、植物繁殖力、植物间距、孢子释放和种群规模条件下，当地种群内部和远离当地种群的有效孢子传播。 该模型的预测将使用成年植物的实验种群进行测试。该模型还将用于预测不同水运动、植物繁殖力、植物间距、孢子释放和种群大小条件下自花受精的频率和空间范围。自体受精对个体健康的影响将在所有生命阶段通过实验确定。从该项目获得的信息将普遍适用于向近岸水域释放活性孢子或幼虫的大量固着海洋生物的扩散模式。这项工作的总体意义在于，它将为促进繁殖体扩散的水动力条件以及繁殖体迁移对被认为具有相对封闭种群的物种动态的影响程度提供急需的见解。此外，这项研究的基于个体的方法将提供有关孢子从个体植物传播出去的信息，这些信息将用于评估巨型海带自体受精的成本，巨型海带是温带海洋藻类优势群体的成员，其生活史分散特性使它们面临自体受精不利影响的高风险。 ***