Collaborative Research: Seed-flow in California Valley Oak (Quercus lobata)--Novel Approaches to an Old Problem

人类造成的干扰，如景观破碎和改变、传播媒介的丧失和全球变暖，要求植物种群能够将基因和个体分散到新的地点。本文介绍了一种基于种皮母体组织分子遗传学分析的种子流研究方法，通过分析分散在景观中的种子集的种子库结构。我们将把这种新颖的分析应用于一种受威胁的树种——加利福尼亚山谷橡树——由橡子啄木鸟传播的种子。我们的目标有两个：(1)对不同情况下种子传播的统计模型进行新的理论工作，从而进行假设检验；(2)考察橡实啄木鸟贮藏地和天然苗区种子库结构和传播距离。这项研究做出了几项有价值的贡献。(1)开发了适用于广泛物种的种子传播研究方法，包括那些经历景观变化和脊椎动物传播媒介丧失的物种。(2)它促进了生态学家和种群遗传学关于种子传播分布形态的日益增多的讨论。(3)这项研究的结果将包括在几个K-12环境研讨会上，与决策者、州和联邦科学家的会议上。

Human-caused disturbances, such as landscape fragmentation and alteration, loss of dispersal agents, and global warming, require that plant populations be able to disperse both genes and individuals to new sites. We introduce an innovative approach to the study of seed flow, based on molecular genetic analysis of maternal tissue in the seed coat, by analyzing the seed pool structure of sets of seeds dispersed across a landscape. We will apply this novel analysis to seed dispersal of a threatened tree species, California valley oak, by the acorn woodpecker. We have two objectives: (1) to conduct novel theoretical work on the statistical model that allows hypothesis testing on seed dispersal under different circumstances; (2) to examine the seed pool structure and dispersal distances of seeds found in acorn woodpecker storage sites, and recruits in natural seedling patches.This research makes several valuable contributions. (1) It develops methods for studying seed dispersal that are applicable to a wide range of species, including those experiencing landscape change and loss of vertebrate dispersers. (2) It contributes to a growing discussion by ecologists and population genetics about the shape of the seed dispersal distribution. (3) Results from this study will be included in several K-12 environmental workshops, meetings with policy-makers, nd state and federal scientists.