Collaborative Research: Controls on the Production and Isotopic Compositions of N2O

PIs将对海洋表面一氧化二氮（N2O）的循环进行研究。这项研究的结果将产生广泛的影响，超出海洋氮循环，因为N2O在平流层臭氧的减少中起着重要作用，本身就是一种重要的温室气体。本研究的主要目标是通过实验室和实地实验相结合，确定N2O产生的生物地球化学条件。更具体地说，PIs建议1)测量自然丰度水平下N2O的N和O2同位素组成，2)进行15N示踪实验以监测通过硝化和反硝化途径产生的N2O，以及3)测量N2O的潜在N和O源的同位素组成。建议在夏威夷海洋时间序列站点（HOT）和北太平洋的巡航上进行实地试验。

ABSTRACTOCE-9810640 & OCE-9817064The PIs will conduct a study on the cycling of nitrous oxide (N2O) in the surface ocean. The results of this study would have broad impact beyond oceanic nitrogen cycling, as N2O plays a significant role in the reduction of ozone in the stratosphere and is itself an important greenhouse gas. The major goal of this study is to identify, using a combination of laboratory and field experiments, the biogeochemical conditions under which N2O is produced. More specifically, the PIs propose to 1) measure N and O2 isotopic compositions of N2O at natural abundance levels, 2) perform 15N tracer experiments to monitor N2O production via nitrification and denitrification pathways, and 3) measure the isotopic composition of the potential N and O sources of N2O. Field experiments at the Hawaii Ocean Time-series site (HOT) and on a cruise in the North Pacific are proposed.