Collecting Gas Samples from Leakin Park, Baltimore, MD (1 of 2) (image) Cary Institute of Ecosystem Studies Share Print E-Mail Caption Groffman and his field team have been measuring nutrient uptake and gas exchange in Baltimore area forests for nearly 20 years. Credit Dan Dillon Usage Restrictions To promote this press release. 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.