Soil (3 of 3) (IMAGE) Stanford University Caption A rancher in Browns Valley, Calif., applies compost to grazed grasslands as part of a carbon sequestration study. Credit Rebecca Ryals 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.