Fig. 4: Modelled gross primary productivity (GPP) for tropical and subtropical zones with ORCHIDEE-CNP.
From: Convergence in phosphorus constraints to photosynthesis in forests around the world
a GPP from ORCHIDEE-CNP simulations assuming N constraints but a high P everywhere (no P constraint). b GPP as in a, but including P constraints according to a version of the multiple regression in Table 2. The colour scale for a, b are at top. c the difference between GPP from the model with N but not P constraints as shown in a and the ORCHIDEE-CNP simulations with P constraints according to b, with colour scale at bottom. (d) the zonal difference in GPP shown in c using 2˚ latitudinal bands and aggregated across longitudes around the globe.
