Measurements (IMAGE) University of Stirling Caption Scientists Dr Mike Billett and Dr Lorna Street conduct measurements of ecosystem level fluxes of carbon dioxide, in light and dark chambers. Picture taken in tall shrub birch communities at Trail Valley Creek, Northwest Territories Canada. Credit University of Stirling 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.