Dissertation Research: Recruitment in a Large-Seeded Tropical Tree

9321553 lLevey植物补充是指植物通过产生后代（种子）来取代自己，从而产生一个自我再生的栖息地的过程。种子传播是指植物通过将种子传播到周围区域来“移动”的过程。大多数植物产生的种子数量远远超过其生存能力，因为在传播之后，老鼠和其他啮齿动物吃掉（并因此杀死）了许多种子。有时，如果种子丰富，啮齿动物可能会储存一些额外的种子，以便在今年晚些时候食用。这些储存的种子中的一些可能会被遗忘并发芽，在这种情况下，啮齿动物充当了“次级”传播者。那些存活下来并发芽的种子面临着许多其他的危险，比如食草昆虫和哺乳动物，霉菌和疾病，以及掉落的树枝和树木。因此，植物的补充是一个复杂的过程，涉及到许多其他物种的相互作用。在正在迅速遭到破坏的热带森林中，我们对植物的补充知之甚少，因此我们缺乏就如何拯救和恢复这些森林提出建议所必需的信息。Ocotea endresiana（与鳄梨有关）是哥斯达黎加Monteverde附近山区森林中的一种常见树木。大的果实被吃掉，种子被相对较少种类的鸟类传播。尽管对一些相关树木的种子传播进行了一些研究，但这些种子的传播后命运尚未得到很好的了解。在本研究中，我们将研究黄貂鱼种子的补充，以确定初级传播、次级传播和种子捕食对幼苗形成的重要性。这项研究将提供一些有关种子传播过程复杂程度的初步信息。这些信息将被证明对那些希望重建——甚至只是维持——自然栖息地的野生动物管理者有用。将研究一系列复杂的种子传播者和捕食者之间的相互关系。每一种都在决定植物的生存中发挥着作用——问题是，这种作用有多重要？如果知道各种主要和次要传播者的作用，就可以预测动物灭绝对种子传播的影响。关于种子传播和植物补充的知识的增加将为理解热带森林如何“工作”提供另一块拼图

9321553 lLevey Plant recruitment is the process by which plants produce offspring (seeds) to replace themselves and thus produce a self- regenerating habitat. Seed dispersal is the process that allows plants to "move" by distributing the seeds throughout the surrounding area. Most plants produce many more seeds than can survive because after dispersal, mice and other rodents eat (and therefore kill) many of the seeds. Sometimes, if seeds are abundant, rodents may store some extra seeds to be eaten later in the year. A few of these stored seeds may be forgotten and may germinate, in which case the rodents are acting as "secondary" dispersers. Those seeds that survive and germinate face many other dangers, such as plant-eating insects and mammals, mold and disease, and falling branches and trees. Thus, plant recruitment is a complicated process of many stages and involves interactions with many other species. In tropical forests, which are being rapidly destroyed, we know very little about plant recruitment, and therefore we lack the information necessary to make recommendations about how to save and restore these forests.%%% Ocotea endresiana (related to avocados) is a common tree in the mountain forests near Monteverde, Costa Rica. The large fruits are eaten and the seeds dispersed by relatively few species of birds. Despite several studies on seeds dispersal of some related trees, the post-dispersal fate of these seeds is not well understood. In this study, recruitment of O.endresiana seedings will be examined to determine the importance of primary dispersal, secondary dispersal, and seed predation on seedling establishment.%%% This research will provide some of the first information on the degree of complexity involved in the seed dispersal process. Such information will prove useful to wildlife managers who hope to rebuild -- or even simply to maintain -- natural habitats. The interrelationships among a complex array of seed dispers ers and predators will be examined. Each one plays a role in determining plant survival -- the question is, how critical is that role? If the roles of various primary and secondary dispersers are known, then one can predict the effects of animal extinctions on seed dispersal. Increasing knowledge of seed dispersal and plant recruitment will provide another piece in the puzzle of understanding how tropical forests "work."***