A simulation model for the effects of burning on the phosphorus and nitrogen cycle of a heathland ecosystem

In this paper, a simulation model is presented for nutrient cycling in heathland ecosystems. The results of simulations are compared with field data of phosphorus and nitrogen accumulation in different compartments of the system in the years after burning, given in the literature on this subject (Chapman, 1967; 1970). It is shown that for the cycling of P the system returns slowly to equilibrium after an initial disturbance. The time span of about 30 years that is required to reach equilibrium is in agreement with the field data. However, P accumulation in living above-ground biomass and litter is overestimated by the model in the first years after burning. Nitrogen accumulation in biomass and litter is systematically underestimated by the model.The results are discussed with reference to the processes in nutrient cycling that are insufficiently understood, and with reference to the management of heathlands.