IVL Swedish Environmental Research Institute

The dynamic integrated ecosystem model ForSAFE-Veg was applied at the intensively monitored experimental catchment Gårdsjön, with the aim to investigate the performance of the model and the feasibility of using the composition of the ground vegetation community as an indicator of potential change due to N deposition. The quality, long term, and integrity of the measured data provided an ideal testing opportunity for evaluating the performance of the model, which proved satisfactory. The study shows that it is feasible to use the composition of the ground vegetation community as a biological indicator of ecosystem change. Yet, to be used in estimating critical loads of nitrogen (N) deposition, the biological indicator has to be simplified into a single-dimensional variable referred to as the average yearly exceedance (of change in the composition of the ground vegetation). The study shows that setting conditions to protect the dominant segment of the plant community, and thereby protecting ecosystem services, will also result in protecting the marginal plants proportion at the site. However, the choice of the segment of the plant community to be protected and the acceptable level of change remain bound to social preferences

The dynamic integrated ecosystem model ForSAFE-Veg was applied at the intensively monitored experimental catchment Gårdsjön, with the aim to investigate the performance of the model and the feasibility of using the composition of the ground vegetation community as an indicator of potential change due to N deposition. The quality, long term, and integrity of the measured data provided an ideal testing opportunity for evaluating the performance of the model, which proved satisfactory. The study shows that it is feasible to use the composition of the ground vegetation community as a biological indicator of ecosystem change. Yet, to be used in estimating critical loads of nitrogen (N) deposition, the biological indicator has to be simplified into a single-dimensional variable referred to as the average yearly exceedance (of change in the composition of the ground vegetation). The study shows that setting conditions to protect the dominant segment of the plant community, and thereby protecting ecosystem services, will also result in protecting the marginal plants proportion at the site. However, the choice of the segment of the plant community to be protected and the acceptable level of change remain bound to social preferences