Deep soil (below 30cm or A-horizon) account for up to 70% of the carbon (C) stored in soils. Decomposition of deep soil organic matter (SOM) contributes to surface carbon dioxide efflux, and is controlled by climate, soil physico-chemical properties, and geomorphology of the landscapes and associated hydrology. Here I will present results on deep SOM dynamics, including SOM in weathered bedrock and how climate regulates SOM storage, chemical composition, persistence, and stabilization mechanisms, In addition, I will discuss the importance of climate-smart soil management for reducing atmospheric burden of CO2, and ensuring food and nutritional security of the human society.
