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sequences, and fire scars in tree rings, long-term changes in fire regimes can be reconstructed
(Conedera et al. 2009, Whitlock et al. 2010). Comparing these records with palaeoclimate, pal-
aeovegetation and archaeological proxies can help in disentangling the complex interplay
between climate, vegetation, fire, and human activities over timescales of hundreds to thou-
sands of years. In historic times (hundreds of years), written records have been kept of fires
and fire management practices, and in recent decades satellite imagery tracks fire frequency
and extent alongside changes in land cover (Whitlock and Anderson 2003, Conedera et al.
2009, Bowman et al. 2011). Integrated approaches are needed that combine long-term data
with current understanding of fire ecology and simulations of interactions between fire, vege-
tation, and climate in the future (Kehrwald et al. 2013). This chapter explores the role of
long-term data in developing new, adaptive ways of managing fire that combine ecological
considerations, long-term fire regimes and societal needs, alongside knowledge of future cli-
matic and economic scenarios.
Shifting baselines
Though humans and fire have been associated for many millennia, long-term studies have
shown that people have had a disproportionate influence on fire regimes over the past few
centuries, the new geological epoch known as the Anthropocene (see Chapter 1) (Steffen
et al. 2007, Zalasiewicz et al. 2010, 2011, Steffen et al. 2011). During the twentieth century, sup-
pression became the dominant fire management strategy in many areas of the world, reflect-
ing a deep-seated mistrust of fire and a conviction of its destructive properties. Many
European farmers and foresters who settled in North America, Australia, and Africa felt that
fire was a damaging influence, and at the same time, early nature conservationists, influ-
enced by the dominance of the equilibrium paradigm (see Chapter 1) sought to protect the
perceived balance between vegetation and climate by preventing disturbances. As a result,
natural fire regimes and traditional fire-management practices were disrupted (Holling and
Meffe 1996, Pausas and Keeley 2014).
The period immediately prior to the Anthropocene might seem a logical benchmark for
fire restoration. But how 'typical' was this period and is it a suitable restoration target? Marlon
et al. (2008) compiled sedimentary charcoal records spanning six continents to document
trends in both natural and anthropogenic biomass burning for the past two millennia.
Between 1750 and 1870 ce, near the putative start of the Anthropocene (Figure 4.1), their study
clearly shows the increase in fire that is attributed to forest clearance by colonial settlers in
the Americas, Europe, and Australia (Marlon et al. 2008). There is then a marked decline in
charcoal from 1870 and 1950 ce, despite increasing human population and rising temperat-
ures. This trend indicates the effects of land-use changes, as well as fire suppression policies.
Immediately prior to the Anthropocene, however, the amount of fire seems unusually low in
comparison with the rest of the 2,000-year record (Figure 4.2).
Palaeo-climatic reconstructions have shown that the thirteenth to the eighteenth centu-
ries, known as the Little Ice Age (LIA), were characterized by unusually cold climates (see
Chapter 5), associated with less plant growth and declining fire regimes (Marlon et al. 2008,
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