Variability in Spore Dispersal and its Role in Kelp Population Dynamics

9614091 RAIMONDI海带森林，全球亚潮温带珊瑚礁的主要特征，经历了相对频繁和不可预测的局部植被和植被。 该项目是正在进行的因果机制调查的继续，这种调查使森林在海带大面积损失后得以迅速恢复。该项目的目标是预测促进巨型海带（Macrocystis pyrifera）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）孢子迁移率在调节当地海带种群动态方面的作用，以及（2）有限扩散通过降低个体适合度而破坏种群稳定的潜力。研究方法是收集水运动的测量值，同时测量孢子的释放和分散从孤立的植物在广泛的物理和生物条件。 这些信息将被用来建立一个基于个人的模型，将预测有效的孢子扩散内和远离当地人口的水运动，植物繁殖力，植物间距，孢子释放和人口规模的不同条件。 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在不同的水运动，植物繁殖力，植物间距，孢子释放和人口规模的条件下，自花受精的频率和空间范围。自体受精对个体适应性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大量固着海洋生物的扩散模式，这些生物将活性孢子或幼虫释放到近岸沃茨。这项工作的一般意义是，它将提供急需的洞察力的水动力条件，促进扩展繁殖体扩散和繁殖体移民的程度influences被认为有相对封闭的种群的物种的动态。此外，本研究的基于个体的方法将提供有关孢子传播远离个体植物的信息，这些信息将用于评估巨型海带自受精的成本，巨型海带是温带海洋藻类的一个主要群体的成员，其生活史和传播特征使其处于高风险的自受精的不利影响。 ***

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. ***