International Research Fellowship Program: Ecological Consequences of Large-Herbivore Declines under Different Rainfall Regimes

国际研究奖学金计划：不同降雨情况下大型草食动物数量减少的生态后果

• 批准号: 0852961
• 负责人: Robert Pringle
• 金额: $ 3.99万
• 依托单位: Pringle Robert M
• 依托单位国家: 美国
• 项目类别: Fellowship
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2011-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0852961&HistoricalAwards=false
• 关键词: International; Research; Fellowship; Program; Ecological

0852961PringleThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).The International Research Fellowship Program enables U.S. scientists and engineers to conduct nine to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad.This award will support a twenty-four-month research fellowship by Dr. Robert M. Pringle to work with Dr. Fabian Haas at the International Centre for Insect Pathology and Ecology (CIPE), with Dr. Charles Warui at the National Museums of Kenya, and with Dr. M. Kinnaird at the Mpala Research in Kenya.Recent studies suggest that large mammalian herbivores may be ?strong interactors? whose removal will precipitate major changes in biological communities. This project aims to document and explain the short-term (2-3 year) responses of plant and invertebrate communities to the exclusion of ungulate herbivores in a Kenyan savanna, and also to examine how these responses are contingent upon variability in rainfall. This is being done using a unique experiment with four 1-ha treatments: total exclusion (removal of all herbivores larger than 4-kg hares), exclusion of all herbivores larger than 6-kg dik-diks, exclusion only of megaherbivores (elephants and giraffes), and unfenced control (all animals present). These treatments are each replicated three times at three levels of a natural rainfall gradient. Project personnel are testing four specific hypotheses. I: Herbivore exclusion alters the palatability of individual plants, enhances recruitment, reduces species evenness, and increases structural complexity at the habitat level. II: Via these effects on plants, herbivore exclusion leads to increased total biomass of both herbivorous and carnivorous arthropods. III: Indirect responses of individual arthropod species vary, but depend on (a) diet breadth and host-plant preference, (b) foraging strategy, and (c) predation vulnerability. IV: The strength of both direct and indirect effects is negatively correlated with rainfall. Humans are reducing large-herbivore populations worldwide, and climate change promises dramatic changes in precipitation patterns. Yet nobody knows how these changes will affect biodiversity and ecological function in iconic landscapes such as African savannas and the Yellowstone ecosystem. Generating this knowledge will reveal fundamental truths about how large mammals influence ecological dynamics and how these influences are modulated by environmental context. It will also provide a basis for predicting the consequences of large-mammal declines and extinctions in a rapidly changing world. To date, measurements of responses to large-mammal removal have been idiosyncratic and opportunistic, and the mechanisms offered to explain underlying the responses are often speculative. Moreover, the few exclusion experiments conducted in species-rich ungulate guilds have mostly been ?all or none,? meaning that the effects of particular species or subgroups cannot be identified, whereas our sequential size-based exclusion approach will isolate these effects. Finally, this experiment is the first to combine large-herbivore exclusion with replication across multiple levels of an environmental gradient, which is consistent with recent calls for ecologists to address the context-dependence of species interactions. In terms of developing human capital and international collaboration, this project supports five full-time research assistants from local communities in rural Kenya. Their employment provides them with valuable, transferable skills (identification of native Kenyan biodiversity, data entry and computer training, management and teamwork experience). These men are also from different ethnic groups and religions in a region torn (as recently as January, 2008) by ethnic strife; working together cements bonds that overcome ethnic differences. Local people and their children will be taken on guided tours of the experimental facilities, allowing them to interact with biodiversity in an educational setting, which will promote environmental stewardship in the region. This project also involves collaboration among three research institutions in Kenya (as well as three universities in the US and Canada) that have long operated separately; this collaboration will build intra- and international partnerships and capacity that will facilitate future joint endeavors. The project also lays a foundation for future work on the poorly known invertebrates of this region. Lastly, the conservation and management implications of the work will be disseminated in short essays for non-scientific audiences to be published both in local Kenyan media and on the worldwide web.

0852961 Pringlethis奖是根据2009年的《美国复苏与再投资法》（公法111-5）资助的。国际研究奖学金计划使美国科学家和工程师能够在国外进行九至二十四个月的研究。 该计划的奖项为联合研究提供了机会，并使用独特或补充的设施，专业知识和国外的实验条件。该奖项将支持Robert M. Pringle博士的二十四个月研究奖学金，与Fabian Haas博士在国际昆虫病理学和生态中心（CIPE）的Fabian Haas博士（CIPE）与Charles Warui博士一起在National Museums of Kinyy M. Kin kin of Kiny of Kiny，M。Kin，肯尼亚的研究表明，大型哺乳动物的草食动物可能是强烈的互动者？其去除将导致生物群落的重大变化。该项目旨在记录和解释植物和无脊椎动物群落对排除肯尼亚稀树草原中解脱食草动物的短期（2 - 3年）的反应，并研究这些反应如何取决于降雨量的可变性。这是使用四种1-HA处理的独特实验进行的：总排除（除去大于4公斤野兔的所有草食动物），排除所有大于6公斤Dik-Diks的草食动物，仅排除Megaherbivores（Elephants and Giraffes和Giraffes）和所有动物（所有动物）。这些处理在自然降雨梯度的三个级别上分别复制了三次。项目人员正在测试四个特定的假设。 I：草食动物的排除改变了单个植物的可口性，增强募集，降低物种均匀度并提高栖息地水平的结构复杂性。 II：通过对植物的这些影响，草食动物的排除导致草食性和食肉性节肢动物的总生物量增加。 III：单个节肢动物物种的间接反应各不相同，但取决于（a）饮食广度和宿主植物偏好，（b）觅食策略，以及（c）捕食脆弱性。 IV：直接和间接影响的强度与降雨呈负相关。人类正在减少全球大型墨西哥生物种群，气候变化有望在降水模式中发生巨大变化。然而，没有人知道这些变化将如何影响非洲稀树草原和黄石生态系统等标志性景观中的生物多样性和生态功能。产生这些知识将揭示有关大型哺乳动物如何影响生态动态以及这些影响如何受环境环境调节的基本真理。它还将为预测迅速变化的世界中大型哺乳动物下降和灭绝的后果提供基础。迄今为止，对大型哺乳动物去除的响应的测量一直是特殊和机会主义的，并且提供了解释基础反应的机制通常是投机性的。此外，在物种丰富的脱水行会中进行的少数排除实验主要是“全部或全部”，这意味着无法识别特定物种或亚组的影响，而我们的基于顺序大小的排除方法将隔离这些效果。最后，该实验是第一个将大墨西哥动物排除与在多个环境梯度上复制的复制相结合的实验，这与最近要求生态学家解决物种相互作用的上下文依赖性的呼吁一致。在发展人力资本和国际合作方面，该项目支持肯尼亚当地社区的五名全日制研究助理。他们的工作为他们提供了有价值的，可转移的技能（肯尼亚本地生物多样性，数据输入和计算机培训，管理和团队合作经验）。这些人也来自族裔冲突的地区（2008年1月）的一个不同种族和宗教。共同努力克服种族差异的粘结。当地人和他们的孩子将被带到实验设施的导游，使他们能够在教育环境中与生物多样性互动，这将促进该地区的环境管理。该项目还涉及肯尼亚的三个研究机构（以及美国和加拿大的三所大学）之间的合作；这项合作将建立内部和国际伙伴关系和能力，以促进未来的共同努力。该项目还为该地区鲜为人知的无脊椎动物的未来工作奠定了基础。最后，这项工作的保护和管理含义将在简短的文章中传播，以便在肯尼亚当地媒体和全球网络上发表非科学受众。