Where new farm woodlands support biodiversity action plans: a spatial multi-criteria analysis

In many developed countries forest cover is growing and the provision of non-market benefits is increasingly important for forestry management. The benefits provided by a new woodland not only depend on the design of the woodland (local site level), but also on its location in the wider landscape. This paper develops a generic GIS-based method to map the potential biodiversity benefits of new woodlands through an integration of species-habitat modelling for a list of 15 key species derived from a “Local Biodiversity Action Plan”, encompassing the Northeast of Scotland, and spatial multi-criteria analysis. For each selected species 'Preferred Future Woodland' maps are produced, indicating the extent to which populations of these species are expected to expand or contract in response to further afforestation. Species are then weighted on the basis of criteria of relative scarcity of suitable habitat and national importance of the regional population. The maps are then combined using this weighting to yield an overall potential biodiversity benefit map, which shows that the areas with the highest potential biodiversity gains are the edges of major agricultural areas (mostly deciduous), the riparian zones (deciduous) and areas adjacent to mature native pine woods (coniferous). It is demonstrated that the use of this map for more explicit spatial targeting of an existing farm afforestation scheme can help to provide much more 'biodiversity value' for taxpayers' money.