Doctoral Dissertation Research: Investigating the Influence of Biotic and Abiotic Factors on Grasslands in the Great Plains Region of the U.S.

博士论文研究：调查生物和非生物因素对美国大平原地区草原的影响

• 批准号: 1558228
• 负责人: Kendra McLauchlan
• 金额: $ 1.13万
• 依托单位: Kansas State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-03-15 至 2017-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1558228&HistoricalAwards=false
• 关键词: Doctoral; Dissertation; Research; Investigating; Influence

NATIONAL SCIENCE FOUNDATIONGEOGRAPHY SPATIAL SCIENCES (GSS) PROGRAMABSTRACTThis doctoral dissertation research project will evaluate the influence of biotic and abiotic factors on grassland composition as exhibited through pollen assemblages. The research will provide new insights into interpretations of pollen from lake sediment cores that reveal changes in vegetation over time and contribute important information about interannual variation in pollen productivity and composition of a natural grassland environment. Although conducted in a contemporary context, the project will help answer important questions in paleoecological research by helping quantify the relationships between pollen (as a vegetation proxy) and key drivers like fire, herbivory, and topography. The project will enhance the value of a long-term dataset that is the longest-running annual record of North American grassland pollen composition. The doctoral student will work with a high school serving underrepresented populations to integrate a research-based module into their science curriculum. In addition, the project also will yield new information and insights to more effectively refine allergy assessments in the health and medical fields. As a Doctoral Dissertation Research Improvement award, this award will provide support to enable a promising student to establish a strong independent research career.North American grasslands emerged about 25 million years ago and have persisted despite dramatic changes in climate and fauna. Over time, and especially throughout the Holocene Epoch, the species composition and the extent of the biome has changed, but the role of the biotic and abiotic factors influencing those changes remain unknown. The doctoral student will conduct this project in a tallgrass prairie in Kansas. The study area is diverse, with variable topography, and includes sites that have experienced a range of different burning and grazing treatments. The research will focus on quantifying the relationships between grassland pollen assemblages and the biotic and abiotic variables influencing the region. This will be accomplished by identifying pollen from multiple traps throughout the study to produce a multi-year set of modern pollen data. The doctoral student will quantify these data in order to assess interannual variations in grassland pollen through multivariate statistical analyses. Outcomes from this research will enable better interpretation of past vegetation cover and facilitate better predictions of grassland response to human-induced shifts in fire and herbivory regimes during a range of current and possible future climatic conditions.

国家科学基金会地理空间科学（GSS）计划捕捞研究研究项目将评估生物和非生物因素对通过花粉组合所展示的草地组成的影响。 这项研究将为对湖泊沉积物核心的花粉解释提供新的见解，这些解释揭示了随着时间的流逝而变化，并为花粉生产率和自然草地环境组成的年际变化提供重要信息。 尽管在当代背景下进行，但该项目将通过帮助量化花粉（作为植被代理）与火灾，草食和地形等主要驱动因素之间的关系来帮助回答古生态研究中的重要问题。 该项目将提高长期数据集的价值，该数据集是北美草原花粉构成最长的年度记录。 该博士生将与一所高中合作，为代表性不足的人群提供基于研究的模块纳入其科学课程。 此外，该项目还将产生新的信息和见解，以更有效地完善健康和医疗领域的过敏评估。 作为博士学位论文研究改进奖，该奖项将提供支持，使有前途的学生能够建立强大的独立研究职业。北美草地大约在2500万年前出现，尽管气候和动物群的变化发生了巨大变化，但仍然持续存在。 随着时间的流逝，尤其是在整个全新世时代，物种组成和生物群落的程度发生了变化，但是影响这些变化的生物和非生物因素的作用仍然未知。 博士生将在堪萨斯州的一家塔格拉斯大草原上进行该项目。 研究区域是多种多样的，具有可变的地形，并且包括经历了各种燃烧和放牧处理的地点。 该研究将重点介绍草地花粉组合与影响该地区的生物和非生物变量之间的关系。 这将通过整个研究中的多个陷阱中的花粉来生成多年的现代花粉数据来实现。 博士生将量化这些数据，以通过多元统计分析评估草地花粉的年际变化。 这项研究的结果将能够更好地解释过去的植被覆盖范围，并促进在当前和未来可能的气候条件的范围内，可以更好地预测草地对人类引起的火灾和草食制度转变的反应。