ABSTRACT
This chapter describes the strong effects of soil carbon (C) stock and its dynamics on the climate change, and vice versa, and managing soil organic carbon (SOC) stocks for mitigation and adaption to the changing climate. The global soil carbon stock consists of SOC and soil inorganic C (SIC). The SOC stock is comprised of the remains of plants, animals, and microbes at various stages of decomposition and of the microbial byproducts. The SIC stock consists of primary or lithogenic carbonates and secondary or pedogenic carbonates. In general, SOC concentration is high in soils of the humid climates and that of SIC in soils of arid and semi-arid regions. The projected climate change will also cause shifts in the precipitation regime along with the attendant changes in soil moisture reserves. The SOC stock increases with increasing precipitation because of the increase in soil moisture regime, the net primary productivity, and input of biomass C into the soil.
