Collaborative Research: Spatial and Temporal Dynamics of Local Extinctions: A 300-Year Experiment

物种灭绝是一个鲜为人知的过程，特别是在局部尺度上，因为很少有生态数据集跨越足够长的时间来揭示灭绝的模式。在地球上，也许没有一个地方的物种组合的变化被仔细地观察和记录了几个世纪。因此，许多关于环境变化后物种灭绝的模式和速度的基本问题很难回答。例如，有多少物种从特定的地方消失了？物种灭绝是在扰动后立即发生，还是扰动后的物种灭绝被推迟，导致未来要偿还“灭绝债务”？这个项目收集的数据将开始填补限制科学家回答这些基本问题的能力的缺陷。传统上用于研究数千年来植物群落变化的古生物学技术将被用于研究过去几百年来植物群落的变化。种子、叶片碎片和花粉将在印第安纳沙丘受干扰湿地的沉积物岩心中进行分析，以创建一个从现在到大约300年前大约十年间隔的长期生态数据集。对这些长期数据的分析将促进生态理论的发展，并通过提供评估当前生态系统变化模式对未来意味着什么的关键信息来帮助保护实践。该项目将为几名本科生、一名高中生、一名高中教师、一名技术人员和一名博士后研究员提供培训和指导。该项目还将支持K-12课程的教育和推广材料的开发。

Species extinction is a poorly understood process, particularly at local scales, because there are few ecological data sets that span long enough time periods to reveal patterns of extinction. There is perhaps no single place on Earth where changes in the local assemblage of species have been carefully observed and documented continuously over several centuries. As a consequence, many basic questions about patterns and rates of species extinction following environmental change are difficult to answer. For example, how many species have been lost from specific local areas? Do extinctions follow immediately after a disturbance, or are post-disturbance extinctions delayed, resulting in an 'extinction debt' to be paid in the future? Data collected by this project will begin to fill a deficit that has limited scientists' ability to answer these basic questions. Paleontological techniques that have traditionally been used to study changes in plant communities over many thousands of years will be used to examine changes in plant communities in the past few hundred years. Seeds, leaf fragments, and pollen will be analyzed in sediment cores from disturbed wetlands in the Indiana Dunes to create a long-term ecological data set for approximately ten-year intervals from the present day to about 300 years ago. Analysis of these long-term data will advance ecological theory and aid conservation practice by supplying information critically needed to gauge what current patterns of ecosystem change mean for the future. This project will provide training and mentorship for several undergraduate students, a high school student, a high school teacher, a technician, and a postdoctoral researcher. The project will also support the development of educational and outreach material for K-12 programs.