REVIEW: Time lag between photosynthesis and carbon dioxide efflux from soil: a review of mechanisms and controls

Abstract CO 2 efflux from soil depends on the availability of organic substances respired by roots and microorganisms. Therefore, photosynthetic activity supplying carbohydrates from leaves to roots and rhizosphere is a key driver of soil CO 2 . This fact has been overlooked in most soil CO 2 studies because temperature variations are highly correlated with solar radiation and mask the direct effect of photosynthesis on substrate availability in soil. This review highlights the importance of photosynthesis for rhizosphere processes and evaluates the time lag between carbon (C) assimilation and CO 2 release from soil. Mechanisms and processes contributing to the lag were evaluated. We compared the advantages…