March 25, 2024 Gherardi, L. A. and O. E. Sala. 2020. Global patterns and climatic controls of belowground net carbon fixation. Proceedings of the National Academy of Science 117(33):20038-20043. Home » Gherardi, L. A. and O. E. Sala. 2020. Global patterns and climatic controls of belowground net carbon fixation. Proceedings of the National Academy of Science 117(33):20038-20043.