Within country targeting of agri-environment funding: A test of different methods

Abstract

Many countries employ agri-environment schemes to lessen the impact of agriculture on biodiversity. Prioritisation has been a feature of schemes in terms of focussing funding on individual species, habitats or regions. For the 2014–2020 Agri-Environment and Climate Scheme Scotland decided on an alternative prioritisation method; for a number (11) of management options funding was made available for areas (10 km × 10 km grid squares) with more than a threshold of priority species present (a subset of species on the Scottish Biodiversity List likely to benefit from the management options). This approach (Simple targeting) takes no account of the different abundances of the priority species or the possibility that rare species’ distributions are not nested within the more common ones.Three alternative methods were used to assess if that targeting could be made more efficient in its coverage of species’ ranges. Rarity Weighted targeting took into account range sizes of different priority species, Uniqueness targeting focussed on maximising the beta-diversity of targeted grid squares, and Marxan targeting used a reserve selection algorithm to solve the minimum set reserve design problem. Assessment was in terms of how well each method covered the range of the priority species, both on average and on minimum representation of each species on the priority list.Rarity Weighted targeting improved the mean representation of species’ ranges across all 11 options, whereas Marxan targeting performed best of the four methods in ensuring a high minimum representation of species. Uniqueness targeting was uniformly poor. These patterns were conserved whatever the threshold of species richness used in the Simple targeting.If funding for agri-environment options is to be targeted to areas where more species can benefit, then the current Simple targeting approach employed in Scotland can be improved upon in its efficiency at channelling funding to where the priority species are found. However, a strategic choice has to be made as to whether maximising the mean coverage of priority species is the most important objective of the targeting process or whether ensuring high minimum coverage of the species is more important; ensuring that rarer species with ranges poorly nested within those of rarer species are well represented in the targeted areas.