Strengthening conservation through green infrastructure : linking protected areas, habitats and species

The green infrastructure (GI) concept was developed to mitigate habitat fragmentation. The European Union (EU) defines GI as “a strategically planned network of natural and semi-natural areas …designed and managed to deliver a wide range of ecosystem services and to improve connectivity of protected areas in order to promote multifunctional landscapes”. Natura 2000, the EU network of protected areas, constitutes the backbone of the EU’s GI. In Sweden, the “Swedish strategy for biodiversity and ecosystem services” bill incorporates GI. I analyzed GI at different spatial, habitat and species scales. These ranged from the entire EU, to Natura 2000 sites in all of Sweden, to boreal forests of northern Sweden, including forest birds and virtual species. A review of the Natura 2000 scientific literature revealed that the majority of studies were at regional or single-site scales; those from the Mediterranean region dominated. Research gaps included underrepresentation of alpine, agricultural, forest and marine habitats, as well as reptiles, amphibians, lichens, and fungi taxa. The Boreal region was also underrepresented. Analyses of the Swedish Natura 2000 network effectiveness for three forest bird species, lesser spotted woodpecker (Dryobates minor), Siberian jay (Perisoreus infaustus) and hazel grouse (Tetrastes bonasia), demonstrated that the majority of sites were of small size and of low functionality. The largest potential habitat increase was linked to surrounding landscapes for the smaller sites. In boreal Sweden, non-protected proxy continuity forests and forests providing Siberian jay habitat can strengthen the high conservation value forest network for GI. Sub-regional differences in functionality of spruce-, pine- and broadleaf forest types require type-specific restoration in different regions. To strengthen conservation through GI, I conclude that future Natura 2000 studies should encompass large spatial scales and modelling approaches. In Sweden, the habitat matrix surrounding the Natura 2000 sites should be carefully managed. Non-protected forest habitat networks in boreal Sweden can improve connectivity of protected areas and support functional GI over large parts of the region.