Paleoproductivity and Oceanic Nutrient Budgets

该项目将解决两个有关海洋生产和养分循环之间长期关系的问题。 (1)出口生产的变化如何影响养分埋藏？ (2)大陆风化提供的养分和沉积物中养分循环的相对作用是什么？ 两个新生代的时间间隔将进行研究：38-20马，纳入13 C和气候的快速变化的时期，以确定不同的生产对有机埋藏和CO2下降的影响，和64-50马，纳入13 C在气候温暖阶段的持续最大值，以确定如何在C循环的大规模变化与生产和营养埋藏。 分析将包括重晶石（作为生产的示踪剂）、活性P（作为营养埋藏的示踪剂）、块状方解石中的13 C以及%CaCO3、蛋白石和有机C，使用来自各种海洋环境的ODP岩心。

This project will address two questions concerning the long-term relationships between ocean production and nutrient cycles. (1) How do changes in export production affect nutrient burial? (2) What are the relative roles of nutrient supply from continental weathering and nutrient recycling from the sediments? Two Cenozoic time intervals will be studied: 38-20 Ma, incorporating periods of rapid variation in 13 C and climate, to determine the effect of varying production upon organic burial and CO2 drawdown, and 64-50 Ma, incorporating a sustained maximum in 13 C during a climatic warm phase, to determine how large-scale changes in the C cycle are related to production and nutrient burial. Analyses will include barite (as a tracer of production), reactive P (as tracer of nutrient burial), 13 C in bulk calcite, and %CaCO3, opal and organic C, using ODP cores from a variety of oceanic settings.