Power Plant, Southwestern Pennsylvania (IMAGE) Cary Institute of Ecosystem Studies Caption In the pursuit of food and fuel, humans are disrupting Earth’s biogeochemical cycles. Credit www.avphotographics.com Usage Restrictions Must be used in conjunction with the press release. 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.