Safeguarding Natura 2000 habitats from nitrogen deposition by tackling ammonia emissions from livestock facilities.

• We evaluated the Flemish policy to reduce ammonia deposition in Natura 2000 areas. • The policy is ineffective in lowering deposition below critical loads. • Emission abatement should extend beyond the livestock sector. • The cost of abatement differs between livestock subsectors. • The effectiveness in individual habitats depends on the sensitivity of the habitat. Nitrogen deposition is one of the main environmental threats to the conservation goals in areas protected by the European Habitats Directive, a problem that is quite pronounced in the livestock-rich region of Flanders, Belgium. Livestock farms are often located close to Natura 2000 areas. Therefore, ammonia emissions from livestock housing and manure storage have a high contribution to the deposition in these nearby protected habitats. In order to control this problem, the Flemish government imposes restrictions on livestock farms that pose a substantial threat to protected habitats nearby. In this paper, we evaluate the effectiveness of this spatially differentiated policy. Using an integrated spatially explicit modeling approach, we were able to show that the effectiveness of this policy is rather limited in terms of reducing the proportion of habitats in exceedance of the critical load for nitrogen. In order to obtain a good status for all sensitive habitats, emission abatement efforts should extend beyond the livestock sector. The effectiveness of the policy is dependent on habitat type and the livestock subsectors contributing to emissions nearby. Furthermore, by means of four different habitat classes, the effectiveness of alternative policy options can be easily assessed on the level of individual habitats. [ABSTRACT FROM AUTHOR]