Summary:

## Leaching Losses of Nitrogen

- Soil mineral nitrogen that remains after plant uptake, immobilization, and denitrification is subject to loss through leaching, which is the dissolved component of hydrologic outflow from the soil column.
- The leaching loss (NFleached) depends on the concentration of dissolved inorganic nitrogen in soil water solution (DIN) and the rate of hydrologic discharge from the soil column to streamflow (Qdis).
- DIN is calculated assuming a constant fraction (sf) of the remaining soil mineral N pool is in soluble form and dissolved in the total soil water.
- For the Century-based formulation in CLM5.0, the leaching acts only on the NO3- pool (assumed to be 100% soluble), while the NH4+ pool is assumed to be 100% adsorbed onto mineral surfaces and unaffected by leaching.
- The total mineral nitrogen leaching flux is limited on each time step to not exceed the soluble fraction of NSsminn.