Bioreactor Illustration (IMAGE) American Society of Agronomy Caption The bioreactor diverts water from the field to remove nitrogen. Credit Illustration provided by L. Christianson and Helmers/Iowa State Extension. Usage Restrictions Please use with story only License Licensed content 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.