Summary:

Maintenance Respiration

The article presents a model for leaf respiration based on leaf nitrogen content per unit area (NS_narea) and temperature acclimation. The model includes:

1. Leaf Maintenance Respiration:
   - Formula: CF_mr_leaf = i_atkin,pft + (NS_narea * 0.2061) - (0.0402 * t_2m,10days)
   - The temperature dependence is described in Chapter 2.9.

2. Live Stem Maintenance Respiration:
   - Formula: CF_mr_livestem = NS_livestem * MR_base * MR_Q10^((T_2m - 20)/10)

3. Live Coarse Root Maintenance Respiration:
   - Formula: CF_mr_livecroot = NS_livecroot * MR_base * MR_Q10^((T_2m - 20)/10)

4. Fine Root Maintenance Respiration:
   - Formula: CF_mr_froot = Σ(NS_froot * rootfr_j * MR_base * MR_Q10^((Ts_j - 20)/10))

The total maintenance respiration cost is the sum of the above components.

The article also notes that for woody vegetation, maintenance respiration costs are not calculated for the dead stem and dead coarse root components, as they are assumed to have no metabolic function.