EAGER: Individual variation in mast seeding patterns

多年生植物的一种常见的繁殖策略被称为“主播”，即种群在多年内间歇性和同步地生产大量种子作物。罕见的高繁殖“肥大”年对生态系统内的食物网产生级联效应，因为种子是各种鸟类、哺乳动物和昆虫物种的食物来源。在进化上，人们认为这种连续几年产生少量种子，然后是一个丰收年的模式是一种保持种子捕食者数量低的方式，以便有更高的种子建立机会。另一种假设是，同时繁殖的个体将具有更高的授粉效率，这将导致产生更多的种子。最大播种的关键组成部分是繁殖率高的年份，其次是播种率低的年份，同一地区的所有个体都做同样的事情。虽然对桅杆种群中个体的研究很少，但有些研究表明种群内的生殖模式存在相当大的差异。有些个体不像其他个体那样同时长桅杆。 该项目将建立在数百棵白色云杉树的独特的基于个体的数据集上，以调查个体植物的繁殖模式，并测试具有不同繁殖模式的个体的后果。了解植物生殖投资的波动是生态学、保护和管理的一个关键挑战。白色云杉是一种具有经济价值的树种，该项目可能会对其管理产生影响。此外，本科生和研究生都将接受科学和传播方面的培训。个体变异影响着种群和群落的稳定性，而主苗的个体变异与森林更新和更高的生态组织水平有关。将从约900棵树中收集年度球果产量的实地数据，将现有数据集延长至8年。从一个子集的树木的球果将进行评估的球果大小，种子数量，发芽成功率，以测试健身结果的生殖模式相对于高繁殖发生在当地。资源分配和桅杆播种也将在昆虫攻击的背景下进行审查。将测量导致昆虫爆发的个体树木的生长和繁殖，以测试与种群不同分配能量的个体是否有更高的生存可能性。该项目将提供经验数据，新的见解，并了解在桅杆播种系统的个体差异的大小及其后果的新方法。

A common reproduction strategy of perennial plants is called "mast seeding", the intermittent and synchronous production of abundant seed crops across years by a population. The rare and high reproduction "mast" years have cascading effects on food webs within ecosystems, as seeds are a food source for a variety of bird, mammal, and insect species. Evolutionarily, it is thought that this pattern of producing low numbers of seeds for several years, followed by a mast year is a way to keep seed predator populations low, in order to have higher chances for seeds to establish. Another hypothesis is that individuals reproducing at the same time will have higher pollination efficiency, which will lead to more seeds being produced. The critical components of mast seeding are years with high reproduction followed by years with low seeding, and all individuals in the same region doing the same thing. Although studies of individuals in masting populations are rare, some have shown considerable variation in reproductive patterns within a population. Some individuals do not mast at the same time as the rest of the population. This project will build on a unique individual-based dataset of hundreds of white spruce trees to investigate patterns of reproduction by individual plants, and to test the consequences for individuals that have different patterns of reproduction from others in their population. Understanding fluctuations in plant reproductive investment is a key challenge in ecology, conservation, and management. White spruce is an economically valuable species, and this project may have consequences for its management. Additionally, both undergraduate and graduate students will be trained in science and communication. Individual variation has impacts on population and community stability, and individual variation in mast seeding has relevance to forest regeneration and higher ecological levels of organization. Field data will be collected on annual cone production from ~900 trees, extending an existing dataset to eight years. Cones from a subset of trees will be assessed for cone size, seed number, and germination success to test fitness consequences of reproductive patterns relative to when high reproduction occurs locally. Resource allocation and mast seeding will also be examined in the context of surviving an insect attack. Growth and reproduction of individual trees leading up to an insect outbreak will be measured, to test if individuals that allocated energy differently from the population have a higher likelihood of survival. This project will provide empirical data, new insights, and a novel approach into understanding the magnitude of individual variation and its consequences in a mast seeding system.