ABSTRACT
Carbon sequestration in terrestrial ecosystems is strongly regulated by nitrogen processes. Many global land models now simulate the carbon and nitrogen interaction. The goal of this chapter is to understand how coupled carbon and nitrogen models at ecosystem and global scales may be represented in the matrix form. Basically, nitrogen transfers among all the organic nitrogen pools can be represented in one matrix equation that is equivalent to the carbon matrix equation. The carbon and nitrogen matrix equations are coupled through the C:N ratio. Mineral nitrogen dynamics, determined by nitrogen input, mineralization, plant uptake, and leaching, can also be described by one equation.
