Collaborative Research: Delivery and Fate of Old Terrestrial Organic Carbon in a Riverine Ecosystem

本跨学科研究结合有机同位素地球化学和淡水生态系统科学，旨在确定年老陆相有机碳（ATOC）从景观输出到大河后的重要性和作用，ATOC在14C中自然耗尽。调查人员将确定古老的陆地有机物进入河流后会发生什么。哈德逊河是本研究的重点，因为先前的工作表明，相当年龄（1000至5000年）的陆生有机质主导了这条河的碳输入。观测、实验和建模将用于确定(1)各季节和各支流向大河输送的ATOC的变异性；(2)河流中ATOC的分解速率；(3)ATOC分解和输出之间平衡的控制；(4)相对于较年轻的陆地输入和河流本身的初级生产，ATOC在促进河流代谢方面的重要性。参与该项目的研究生和本科生将接受多学科培训，加强三所合作院校之间的研究和教育联系。调查人员将继续与哈德逊河外展组织（Clearwater, Scenic Hudson）进行互动，将项目结果传达给公众。现代河流受几个世纪前森林中产生的有机物影响的观点是一个迷人的框架，可以用来教育公众了解碳循环，特别是河流，以及大陆和海洋之间不可分割的联系。

This interdisciplinary study, combining organic isotope geochemistry and freshwater ecosystem science, seeks to determine the importance and role of Aged Terrestrial Organic C (ATOC, which is naturally depleted in 14C) after it is exported from landscapes to large rivers. The investigators will to determine what happens to old terrestrial organic matter once it enters a river. The Hudson River is the focus of this study because prior work has shown terrestrial organic matter of considerable age (1000 to 5000 years old) dominates C inputs to this river. Observations, experiments and modeling will be used to determine (1) the variability in ATOC delivery to large rivers across seasons and among tributaries, (2) decomposition rates of ATOC within rivers, (3) controls on the balance between ATOC decomposition and export, and (4) the importance of ATOC in fueling riverine metabolism, relative to younger terrestrial inputs and to primary production within rivers themselves. Graduate and undergraduate students working on this project will receive multi-disciplinary training that will strengthen research and education linkages among three collaborating institutions. The investigators will continue to develop interactions with Hudson River outreach organizations (Clearwater, Scenic Hudson) to communicate project results to the general public. The idea that a modern river is influenced by organic matter produced in forests centuries ago is a captivating framework with which to educate the public about the C cycle in general and rivers in particular, and the inextricable link between continents and the ocean.