Measuring Nitrogen Fixation at Sea (image) Duke University Share Print E-Mail Caption A sampler is deployed from a research ship to collect seawater samples for measuring nitrogen fixation rates and characterizing microbial communities. Credit Credit: Weiyi Tang, Duke Univ. Usage Restrictions None Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.