Dissertation Research: Linking coexistence at local and regional scales by assessing a dormancy-dispersal tradeoff

论文研究：通过评估休眠与分散的权衡，将地方和区域尺度的共存联系起来

• 批准号: 1500917
• 负责人: Nelson Hairston
• 金额: $ 2.09万
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-05-01 至 2018-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1500917&HistoricalAwards=false
• 关键词: Dissertation; Research; Linking; coexistence; local

Understanding how and if species can coexist stably in a fragmented habitat where patches are connected by dispersal is key to understanding the maintenance of biodiversity. The coexistence of similar species?ones that feed at the same level in a food chain, have similar life histories, and share predators?requires some form of tradeoff such that each is either limited by different resources or enemies, or each is a superior competitor to the other at some points in either space, time, or both. This project will elucidate the differences in life-history strategies of two grazing zooplankton, Moina macrocopa and Daphnia pulex/pulicaria, in a freshwater rock-pools on an island off the coast of Maine, USA. The dormancy and dispersal of each species will be examined to determine if these differences promote coexistence either alone or in combination with spatial and temporal variation. This study will experimentally test whether one species is superior at remaining dormant while one species is superior at dispersing, and will model whether or not this allows these two species to coexist. This project will train one Ph.D. student and multiple undergraduate students through field-assistantships and mentored independent projects. The research will be communicated to the public, K-12 students, and undergraduates from many institutions at a nearby biological field station. The research itself promotes the progress of science and has implications for national welfare through application to the management of biodiversity of fragmented habitats; the project also supports education and diversity.Understanding how and if species can coexist stably in a fragmented habitat is key to understanding the maintenance of biodiversity. The coexistence of similar species?ones that feed at the same trophic level, have similar life histories, and share predators?requires some form of tradeoff such that each is either limited by different resources or enemies, or each is a superior competitor to the other at some points in either space, time, or both. The differences in life-history strategies of two grazing zooplankton, Moina macrocopa and Daphnia pulex/pulicaria, will be elucidated for a freshwater rock-pool metacommunity on an island off the coast of Maine, USA. Life history strategies relating to dormancy and dispersal of each species will be examined and used to determine if these differences promote coexistence either alone or in combination with spatial and temporal variation. This study will experimentally test (1) whether one species is superior at remaining dormant while one species is superior at dispersing, and (2) whether or not this allows these two species to coexist in this metacommunity by measuring the necessary relationships to parameterize a mathematical dormancy-dispersal model to test the conditions for coexistence. The spatial and temporal dispersal rates of diapausing eggs and their establishment success will be measured by stocking focal pools surrounded by other pools in which the species are initially absent. These data will be combined with data on competition outcomes in both artificial mesocosms and manipulated rock pools. In addition to furthering our understanding of the maintenance of biodiversity, which can be applied to the management of naturally and anthropogenically fragmented habitats, this project will train one Ph.D. student and multiple undergraduate students through field-assistantships and mentored independent projects. Furthermore, the information about this project will be disseminated to visitors to Shoals Marine Laboratory, which includes the public, K-12 students, and undergraduates from many institutions.

了解物种如何以及是否能够在分散的栖息地中稳定共存，其中斑块通过分散连接在一起，是了解生物多样性维护的关键。相似物种的共存——在食物链中处于同一水平，有相似的生活史，并且有共同的捕食者——需要某种形式的权衡，这样每个物种要么受到不同资源或敌人的限制，要么都是更优秀的竞争对手在空间、时间或两者的某些点上与对方发生联系。该项目将阐明美国缅因州海岸附近一座岛屿淡水岩石池中两种食草浮游动物（Moina macrocopa 和 Daphnia pulex/pulicaria）生活史策略的差异。将检查每个物种的休眠和扩散，以确定这些差异是否单独或与空间和时间变化相结合促进共存。这项研究将通过实验测试一种物种是否更擅长保持休眠，而另一种物种更擅长分散，并将模拟这是否允许这两个物种共存。该项目将培养一名博士生。通过现场助理和指导的独立项目，学生和多名本科生。该研究将在附近的生物现场站向公众、K-12 学生和来自许多机构的本科生进行宣传。研究本身促进了科学进步，并通过应用于破碎栖息地的生物多样性管理对国家福利产生影响；该项目还支持教育和多样性。了解物种如何以及是否能够在支离破碎的栖息地中稳定共存是了解维持生物多样性的关键。相似物种的共存——以相同营养级为食、有相似的生活史、有共同的捕食者——需要某种形式的权衡，这样每个物种要么受到不同资源或敌人的限制，要么都是比另一个更优秀的竞争对手在空间、时间或两者的某些点上。将在美国缅因州海岸附近的一个岛屿上的淡水岩石池元群落中阐明两种食草浮游动物（Moina macrocopa 和 Daphnia pulex/pulicaria）生活史策略的差异。将检查并使用与每个物种的休眠和扩散相关的生活史策略来确定这些差异是否单独促进共存或与时空变化相结合。这项研究将通过测量必要的关系来参数化数学模型，通过实验来测试（1）一个物种是否更擅长保持休眠，而一个物种是否更擅长分散，以及（2）这是否允许这两个物种在这个元群落中共存。休眠分散模型来测试共存条件。滞育卵的空间和时间扩散率及其建立成功率将通过放养焦点池来衡量，这些焦点池周围环绕着最初不存在该物种的其他池。这些数据将与人造中宇宙和人工岩石池中的竞争结果数据相结合。除了进一步加深我们对生物多样性维护的理解（可应用于自然和人为破碎栖息地的管理）之外，该项目还将培训一名博士生。通过现场助理和指导的独立项目，学生和多名本科生。此外，有关该项目的信息将向肖尔斯海洋实验室的参观者传播，其中包括公众、K-12 学生和来自许多机构的本科生。