The PCA shows the correlation between species composition, and amount of burned forest area for 1-3 years, 4-6 years and 7-9 years before sampling. There was a positive association between Enicmus rugosus, Corticaria ferruginea, Corticarina fuscula, Pteryx suturalis and Melanophila acuminata and the area of burned forest between 2007 and 2010 in the smaller spatial scale (PCA A). Anthaxia quadripuntata, Rhizophagus nitidulus shows a slightly weaker association with the area burned forest in the larger spatial scale. The association between abundance of the seven pyrophilous beetles weakens with time since forest fires (PCA B & C). Four of eleven pyrophilous beetles showed no or negative association with forest fires in any temporal and spatial scale.

PCA biplots (eigen value PC1=49.9 % and PC=19.6 %) on the abundance of seven pyrophilous beetles in the different sites. The black lines are species abundance descriptors for the pyrophilous Coleoptera species. The orange lines represent supplementary variables; the area of burned forest within each 41 radii, ranging from 100 m to 20000 m, for each smoke trap. Biplot A shows the area of burned forest between 2007 and 2010, biplot B shows 2003-2006 and biplot C shows 1999-2002.

The pyrophilic beetles were more associated with forest fires in the smaller spatial scale ranging from 100 m to 5000 m. Pyrophilic beetles were also more abundant in the north-eastern parts of Östergötland county.

t-value, from generalized linear models of odds of finding the pyrophilic beetles associated with recent forest fires among other beetles against area of burned forest for each radii from the smoke attraction trap. The lines describes the t-value for the three different time scales of fire history, yellow line 2007-2010, red line 2003-2006 and blue line 1999-2002.The X-symbols represent latitude and ▲-symbols represent longitude.