The simulation model described in the first part of this paper is extrapolated into the whole study area in combination with the water balance data. Total nutrient input and output can be calculated from the model. Validation against field data indicated that the preliminary model is robust enough to simulate the nutrient distribution in the system (correlation coefficiency R TN = 0.717; R SRP = 0.821, higher than the significant value 0.708). But the process model used for the reed field is much...