A Burning Question: Can Long-term Data Inform Fire Management in the Twenty-first Century? - Biodiversity Conservation and Environmental Change - page 67

Short-term memory can skew perceptions of how landscapes should look, and observa-
tions over recent decades need to be viewed in a longer-term perspective that places human
impacts in the context of longer-term ecological variability. A further scenario of human
impact on savanna-forest mosaics has emerged from west Africa and Amazonia, where
islands of forest have proved to be anthropogenically derived. In Kissidigou, West Africa the
mosaic of dense, semideciduous rainforest patches and open expanses of grassy savanna was
assumed to be a product of forest clearance. However, historical sources, ethnographic inter-
views, and satellite images revealed that forest islands were actually grown on savanna land
by Kuranko and Kissi farmers, who suppressed fires and cultivated forest patches for subsist-
ence, social, and ritual reasons (see Chapter 6) (Fairhead and Leach 1996, Fairhead 1996).
Similarly, in Amazonia, Mayle et al. (2007) found evidence that some forest islands in the
Llanos de Moxos, in the Beni basin, Bolivia were associated with human management. As
well as the forest islands, the landscape is rich in other anthropogenic legacies, including
earthworks, fish weirs, and causeways, and the Beni Biosphere Reserve now protects endan-
gered species, promotes the sustainable use of natural resources, and safeguards traditional
techniques and knowledge in the area (Mayle et al. 2007).
Many more palaeoecological studies are needed to distinguish ancient primary grasslands,
savannas and heathlands from recent anthropogenic ones, and to study their resilience or
otherwise to changes in fire, grazing, and climate. A preoccupation with closed canopy for-
ests in conservation has been to the detriment of more nuanced management approach that
incorporates the full range of landscape heterogeneity (Gillson and Willis 2004, Parr et al.
2014), though this in now changing with the recognition of cultural landscapes as viable con-
servation targets (see Chapters 6 and 7).
The long co-evolution of fire regimes and humans, and the complex feedbacks in play
between climate, vegetation, and fire, mean that it is often very difficult to separate 'natural'
from 'anthropogenic' fires (Bowman and Haberle 2010, Bowman et al. 2011). From the middle
Pleistocene, about 800,000 to 700,000 years ago, hominins learned how to light, preserve,
and transport fires; they influenced fire regimes by changing the frequency, intensity, or spa-
tial configuration of fire (Bowman et al. 2011). Fire management allows the manipulation of
the structure and abundance of fuel biomass in order to maintain favoured plants and habi-
tats and facilitate hunting. Over time, various cultures have used fire to manage natural
resources, including improving hunting and grazing, clearing areas for crop cultivation, for-
estry, and silviculture. Fire management can also be used to protect infrastructure, houses
and agricultural land, damage property or crops through arson, or as a weapon in warfare
(Bowman et al. 2011, Penman et al. 2011). Fire may even have shaped hominid evolution,
because cooking food reduced the calorific costs of digestion, enabling more efficient hunt-
ing and gathering, and possibly contributing to the development of large brain size (Wrang-
ham and Conklin-Brittain 2003). The domestication of fire has had profound effects on the
biosphere, encouraging the spread of fire-adapted ecosystems at the expense of those that
are fire intolerant (Caldararo 2002, Bond and Keeley 2005, Bond et al. 2005).
Fire regimes are therefore a product of culture, tradition, and social needs as well as envi-
ronmental factors and a pyrogeogrpahic framework, incorporating biological, environmental