Dissertation Research: Empirical and Theoretical Studies of Seed Dispersal in Jacaranda copaia.

该研究的主要目的是直接测量一种常见的、风分散的、间隙定域的热带树木——蓝花楹（Jacaranda copaia）的种子传播距离和差异沉积模式。分散将通过在大型种子诱捕器阵列中捕获的分散种子周围的母体组织进行基因分型来测量。这些将与绘制的人群中的成年基因型相匹配。这些数据将用于回答以下问题：(1)蓝花楹长距离种子传播（这里定义为距离大于100米的传播）的频率有多高？远距离传播在年内和年内是如何变化的？(2)目前的逆扩散模型和机械扩散模型对上述扩散模式的估计和预测效果如何？(3)哪些生物和非生物因素决定了传播距离？(4)蓝花楹种子是否不成比例地散布到树落间隙？随着人类不断改变和破坏热带森林景观，了解调节种群和维持多样性群落的过程对于预测这些种群未来的反应至关重要。扩散是决定生态和种群遗传随时间和空间变化的主要过程。关于种子在自然植物种群内和种群间传播的频率、模式和机制的数据相当缺乏。这项研究是利用遗传技术直接测量种子传播距离的第一次也是最全面的尝试之一。它将直接告诉自然资源保护主义者和土地管理者，根据种子运动的空间范围，维持热带树木种群所需的栖息地的适当大小。

The primary objective of the study is to directly measure seed dispersal distances and differential deposition patterns in a common, wind-dispersed, gap colonizing tropical tree, Jacaranda copaia. Dispersal will be measured by genotyping maternal tissue surrounding dispersed seeds captured in large seed trap arrays. These will be matched to adult genotypes within the mapped population. The data will be used to answer the following questions: (1) How frequent is long distance seed dispersal (here defined as dispersal at distances greater than 100m) in Jacaranda? How does long distance dispersal vary within and among years? (2) How well do current inverse and mechanistic dispersal models estimate and predict dispersal patterns measured above? (3) What biotic and abiotic factors determine dispersal distances? And (4) Are Jacaranda seeds disproportionately dispersed to tree fall gaps?As humans continue to alter and fragment tropical forest landscapes, knowledge of the processes that regulate populations and maintain diverse communities is critical for predicting how these populations will respond in the future. Dispersal is chief among the processes that will determine the ecological and population genetic response over time and space. There is a considerable void of data on the frequency, patterns, and mechanisms of seed dispersal within and among natural plant populations. This study is among the first and most comprehensive attempts to obtain direct measurements of seed dispersal distances using genetic techniques. It will directly inform conservationists and land managers about the appropriate size of habitat required to maintain populations of tropical trees in light of the spatial extent of seed movement.