Woodland key habitats for functional forest landscape green infrastructure in the Swedish mountain region

Sammanfattning: The intact forest landscapes along the Scandinavian Mountain range are of very high conservational value both nationally and internationally, due to their intact characteristics and biodiversity. The high nature conservation values have remained as a result of restricted forest clear-cutting above the so-called mountain forest border (MFB). The Swedish Forest Agency (SFA) has mapped Woodland Key Habitats (WKHs) and Woodland habitats (ONVs) that hold high or semi-high biodiversity qualities in 38 squares (5 x 5 km) in NW Sweden to test the newly developed regionally adapted WKH inventory. This study aims to evaluate how previously registered WKHs of three focal WKH-types and corresponding newly identified WKHs and ONVs, as well as baseline forests with no documented conservation values, contribute to a functional forest landscape green infrastructure in NW Sweden. I arranged field inventory data (collected by the SFA in 2018) in four assessment sets with various nature conservation values and used national land cover data to assign these sets to the three focal WKH-types. By performing a Morphological Spatial Patter Analysis, data were stratified into core, edge, and corridor for analyses of their spatial arrangement and connectivity. Here, increased connectivity was set equal to increased core and corridor area. I found that natural coniferous forest is a strongly dominating WKH-type and that most other WKH-types occurs at low frequency and areal cover. Moreover, I found a general significant increase in natural coniferous forest core, edge, and corridor absolute area from the previously registered WKHs to the following assessment sets of various nature conservation values, representing a potential increase in connectivity. In addition, the MFB represents an actual border, with a notable larger natural coniferous forest core area above the border and a higher edge/core-ratio below. Importantly, my results highlight a higher potential to meet the Aichi target #11 of 17 % protected area important for biodiversity above the MFB, while substantially larger areas of conservational value and functionality will have to be added below. My results clearly show that especially the newly identified WKHs, but also the newly identified ONVs, are key elements in improving the functional forest landscape green infrastructure in NW Sweden.