Additional costs of nature management caused by deposition

Effects of atmospheric deposition on natural areas can be mitigated by management. For example, the effects of excessive nitrogen deposition can partly be overcome by intensifying measures like mowing or sod cutting. The costs of this extra management may, in the future, no longer be required when deposition rates decrease. We developed a method to calculate the costs of the intensified nature management that is required at increased deposition rates. We used a set of models that simulate the biomass development under different management regimes necessary to maintain a certain level of biodiversity. The costs were calculated for several vegetation types based on, among others, the biomass and litter that was removed. Preliminary results show that the models can be applied with some success to assess these costs. Model outcomes show a clear effect of management intensity on biomass growth in heathland and grassland although no differences were found in forest. The biodiversity in heathlands clearly increased when management was intensified. As an example, the extra costs in heathlands that are made to counteract the effects of atmospheric deposition were calculated for The Netherlands. The costs of maintaining heathlands with sods being removed from heathlands every 20 years (presently the usual rate) exceed those in a situation of sod cutting every 60 years (the expected rate without atmospheric deposition) by 1.4 m Euro per year.