SGER: Determining Seed Bank Age Structure with Tandem Accelerator Mass Spectrometry C14 Dating

SGER：使用串联加速器质谱 C14 测年确定种子库年龄结构

• 批准号: 9520888
• 负责人: D. Lawrence Venable
• 金额: $ 2万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-04-15 至 1996-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9520888&HistoricalAwards=false
• 关键词: SGER; Determining; Seed; Bank; Age

9520888 Venable There are many questions in both pure and applied ecology for which an understanding of seed bank dynamics and seed age structure is critical. These include an understanding of succession, extinction and colonization dynamics, revegetation policies, and weed management. Traditionally, the only way to determine seed bank age structure has been to follow seed cohorts for many years. This project will use new techniques involving Tandem Accelerator Mass Spectrometry (TAMS) to date modern seed banks with 14C. This technology, in conjunction with the variable levels of atmospheric 14C as a result of nuclear bomb testing which peaked in 1963, should permit accurate estimates of the ages of seeds produced over the last 30 years. This procedure will be tested with seeds of a Sonoran Desert annual plant. The dating procedure will be calibrated with seed of known age and then utilized to age a carefully sampled seed bank of this desert annual. It is widely believed that long-lived seed banks play an important role in the ecology of desert annuals and desert annuals have played an important role as model organisms in the development of our understanding of adaptation to environmental variability and community dynamics in variable environments. Long-term demographic data are available for desert annuals at the study site. The long-term data will aid in the interpretation of the 14C dates, because differences in production of seeds over the last 14 years can be compared to their incorporation into the seed bank. Likewise, the 14C dates will aid in the interpretation of the long-term data by permitting estimation of the role of seed retention in population dynamics. The research in this Small Grant for Exploratory Research proposal will lead to important breakthroughs in the development of technology that will permit in-depth understanding of long-term community dynamics and diversity. Seed bank age structure is critical in many habitats for many ecological questions, and TAMS 14C aging of seeds for up to 30 years of age would constitute a major methodological breakthrough.

9520888 Venable在纯生态学和应用生态学中有许多问题，对种子库动态和种子年龄结构的理解至关重要。 这些包括对演替、灭绝和殖民动态、重新植被政策和杂草管理的理解。传统上，确定种子库年龄结构的唯一方法是跟踪种子队列多年。该项目将使用包括串联加速器质谱（TAMS）的新技术来确定现代种子库的14C。这项技术，再加上1963年核弹试验导致的大气中14 C含量的变化，应该可以准确估计过去30年生产的种子的年龄。该程序将用索诺兰沙漠一年生植物的种子进行测试。定年程序将与已知年龄的种子校准，然后利用年龄仔细采样的种子库，这一沙漠一年生植物。人们普遍认为，长寿命的种子库在荒漠一年生植物生态学中发挥着重要作用，荒漠一年生植物作为模式生物在我们对环境变化的适应性和可变环境中的群落动态的发展中发挥了重要作用。研究地点有沙漠一年生植物的长期人口数据。长期数据将有助于解释14C日期，因为过去14年种子产量的差异可以与它们纳入种子库进行比较。同样，14C的日期将有助于解释长期数据，允许估计种子保留在种群动态中的作用。 这项探索性研究小额赠款提案中的研究将导致技术发展的重要突破，从而深入了解长期的社区动态和多样性。种子库年龄结构在许多生境中对许多生态问题至关重要，TAMS 14 C老化种子长达30年将构成一个重大的方法学突破。