Figure 2
From: Regional paleofire regimes affected by non-uniform climate, vegetation and human drivers
Biomass burning activity from the compositing of charcoal records and vegetation biomass expressed as total conifers and broadleaf tree biomass computed for the main tree genus, i.e. Abies, Acer, Betula, Picea, Pinus, Populus for the open coniferous forest/tundra
(a,b), boreal coniferous forest (c,d), boreal mixedwood forest (e,f), temperate forest (g,h) and all sites (subcontinental average: i,j). The black and red lines correspond to the scatter plot smoother calculated using a 500 and 200 year window half width, respectively. The grey (biomass burning) and coloured (biomass) areas represent the 95% confidence interval calculated using the bootstrap procedure (calculated on the 500-yr trend). Blue and orange lines highlight periods when the conifer vs broadleaf trees ratio is above (orange) or below (blue) the long-term (7000 yr) average (see Supplementary Fig. 3).
