Figure 2
From: Indigenous impacts on north Australian savanna fire regimes over the Holocene
Multi-proxy diagram showing change in SPAC (stable polycyclic aromatic carbon) mass accumulation rate (as a proxy for fire intensity), charcoal particle count (as a proxy for fire frequency), the fraction of grass relative to total terrestrial pollen counts (as a proxy for vegetation), δ13CSPAC values (as a proxy for source of burning), and δD values of n-C27 and n-C29 alkanes (as a proxy for monsoon strength) from core GIR2 over the Holocene. The most recent sample for MARSPAC (326 μg cm−2 yr−1) is removed as it represents European induced fire regime. Also shown are Generalized additive models (GAMs) as a blue line through the GIR2 data with confidence levels (significance = 0.9) shaded. Corresponding right panels show first derivatives calculated from the GAM splines. Significant positive (negative) trends are highlighted in red (blue) with significance set to 0.975.
