The Seagrass History of Florida Bay Reconstructed from Integrating Micropaleontological and Geochemical Proxies

综合微体古生物学和地球化学指标重建的佛罗里达湾海草历史。放大图片作者：柯林斯，James W. Fourqurean，William T.安德森佛罗里达国际大学沿海环境条件的变化有多少是自然发生的，有多少是由人类引起的？ 这个问题是解决与海草丰富的历史记录，今天是高度相关的环境水质。这项研究以佛罗里达湾为背景，它是环境受到挑战的大沼泽地国家公园的一部分。 主要目的是收集佛罗里达湾沉积物的核心，并使用其中包含的海草丰度的代理作为过去几百年的环境水质的指标。使用代用品是因为海草本身并不保存在沉积物中。地球化学代用指标是有机质（有机碳、氮、分子生物标志物、稳定同位素-d13 C、d15 N、dD）的量度，微体古生物代用指标是海草指示物种（有孔虫、硅藻）的丰度。最近，高盐度与佛罗里达湾的大量海草死亡有关。 还将使用几个代用指标来确定历史盐度与海草变化之间的相互关系。这笔赠款资助试点项目，从佛罗里达湾提取沉积物岩心，进行沉积学分析，确定放射性年龄，并校准现代海草丰度和盐度的代理。随后，研究人员将从岩心中收集地球化学和微体古生物学数据，将数据整合到统计分析中，并解释结果。知识是先进的，将结果在地质学，生物学和化学课上教授的调查人员，并提供了三个研究生论文的基础。FIU是一所联邦承认的少数民族大学。

ABSTRACTThe Seagrass History of Florida Bay Reconstructed from Integrating Micropaleontological and Geochemical ProxiesLaurel S. Collins, Rudolf Jaffe, James W. Fourqurean, William T. AndersonFlorida International UniversityHow much of the variation in coastal environmental conditions is naturally occurring and how much has been caused by humans? This question is addressed with the historical record of seagrass abundance, which today is highly correlated with environmental water quality. The study is set in Florida Bay, part of the environmentally challenged Everglades National Park. The main objective is to collect cores of Florida Bay sediment and use proxies of seagrass abundance contained therein as indicators of the environmental water quality for the past few hundred years. Proxies are used because seagrass itself is not preserved in sediments. The geochemical proxies are measures of organic matter (organic carbon, nitrogen, molecular biomarkers, stable isotopes - d13C, d15N, dD) and micropaleontological proxies are abundances of seagrass indicator species (foraminifera, diatoms). Hypersalinity has recently been linked to large seagrass die-offs in Florida Bay. Several proxies will also be used to determine the correlation between historical salinity and seagrass changes. This grant funds the pilot project to extract sediment cores from Florida Bay, conduct sedimentologic analyses, determine radiometric ages, and calibrate the proxies to modern seagrass abundances and salinities. The investigators will subsequently collect geochemical and micropaleontological data from the cores, integrate the data in statistical analyses, and interpret the results. Knowledge is advanced by incorporating the results in geology, biology and chemistry classes taught by the investigators, and providing the basis for three graduate student theses. FIU is a federally recognized minority university.