Emerald Lake (IMAGE) University of California - Riverside Caption Long-term monitoring of Emerald Lake shows that productivity is increasing due to greater input of nutrients like nitrogen and phosphorus. New research being conducted at UCR will attempt to understand the underlying causes of these changes and determine critical doses for these nutrients. Credit James Sickman, UC Riverside. Usage Restrictions None 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.