Both ongoing climate change and land use change threaten the functioning and
resilience of forests and savannas in central Africa. Increasing annual rainfall will
certainly favor forests (Malhi et al. 2009) and could even improve crop yields in
savanna areas (Sonwa et al. 2011; IPBES 2018). Even though we have not explored
how seasonality and temperature are projected to change by 2070, other studies have
predicted important shifts in composition (Sala et al. 2000) and vegetation structure
(Aleman et al. 2016, 2017). In addition, even though forest in central Africa are
carbon sinks that sequester large volumes of carbon annually (Lewis et al. 2009),
massive emissions could be expected in specific years due to drought-related tree
dieback (Allen et al. 2010; Bennett et al. 2015), as reported for the Amazon (Phillips
et al. 2009). This phenomenon has, however, not yet been reported in central Africa.
Section 9.3.3 outlined how savannas are specifically targeted for reforestation and
the production of biofuel and cash crops, largely because they are perceived to have
lower conservation value than forests (see Alexandratos and Bruinsma 2012;
Searchinger et al. 2015). Currently >30% of forests in central Africa have been
granted to logging companies. Even though increasing protected area coverage may
help prevent the further degradation of both forests and savannas (especially
savannas that only have 12.2% of their area under protection), there is a widespread
concern that protected areas are not effective in the region, primarily due to conflicts
and poor governance (Chape et al. 2005) (Chap. 1, Vol. 1). This potentially
compromises their effectiveness in maintaining forest and savanna resilience.
Indeed, protected areas in tropical areas are increasingly threatened due to population increase (Laurance et al. 2014) and especially funding constraints (Bruner et al.
2004) (Chap. 1, Vol. 1). Illegal logging, grazing, and agriculture commonly occur
inside poorly enforced protected areas (Laurance et al. 2012), especially in west and
central Africa (Tranquilli et al. 2014). Agricultural expansion near protected areas
tends to erode biodiversity and ecosystem services due to edge effects (Wittemyer
et al. 2008; Laurance et al. 2014). However, if the integrity of protected areas can be
maintained, for example, by involving local communities (Vodouhê et al. 2010),
then central African forests and savannas may remain relatively resilient in the face
of these threats, and future climate change (Chap. 10, Vol. 1).
9.4.2 Policy Implications and Recommendations
Based on the comprehensive analysis of the past, present, and future vegetation
patterns in central African forests and savannas, we identify two main policy
relevant findings: (a) mesic savannas are not degraded forests and (b) forests and
savannas have experienced a long history of climate changes and human activity,
which offers insights for their effective management.
Considering that forests and savannas in central Africa offer habitat for biodiversity and contribute manifold to the livelihoods of local communities (see
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J. C. Aleman and A. Fayolle
resilience of forests and savannas in central Africa. Increasing annual rainfall will
certainly favor forests (Malhi et al. 2009) and could even improve crop yields in
savanna areas (Sonwa et al. 2011; IPBES 2018). Even though we have not explored
how seasonality and temperature are projected to change by 2070, other studies have
predicted important shifts in composition (Sala et al. 2000) and vegetation structure
(Aleman et al. 2016, 2017). In addition, even though forest in central Africa are
carbon sinks that sequester large volumes of carbon annually (Lewis et al. 2009),
massive emissions could be expected in specific years due to drought-related tree
dieback (Allen et al. 2010; Bennett et al. 2015), as reported for the Amazon (Phillips
et al. 2009). This phenomenon has, however, not yet been reported in central Africa.
Section 9.3.3 outlined how savannas are specifically targeted for reforestation and
the production of biofuel and cash crops, largely because they are perceived to have
lower conservation value than forests (see Alexandratos and Bruinsma 2012;
Searchinger et al. 2015). Currently >30% of forests in central Africa have been
granted to logging companies. Even though increasing protected area coverage may
help prevent the further degradation of both forests and savannas (especially
savannas that only have 12.2% of their area under protection), there is a widespread
concern that protected areas are not effective in the region, primarily due to conflicts
and poor governance (Chape et al. 2005) (Chap. 1, Vol. 1). This potentially
compromises their effectiveness in maintaining forest and savanna resilience.
Indeed, protected areas in tropical areas are increasingly threatened due to population increase (Laurance et al. 2014) and especially funding constraints (Bruner et al.
2004) (Chap. 1, Vol. 1). Illegal logging, grazing, and agriculture commonly occur
inside poorly enforced protected areas (Laurance et al. 2012), especially in west and
central Africa (Tranquilli et al. 2014). Agricultural expansion near protected areas
tends to erode biodiversity and ecosystem services due to edge effects (Wittemyer
et al. 2008; Laurance et al. 2014). However, if the integrity of protected areas can be
maintained, for example, by involving local communities (Vodouhê et al. 2010),
then central African forests and savannas may remain relatively resilient in the face
of these threats, and future climate change (Chap. 10, Vol. 1).
9.4.2 Policy Implications and Recommendations
Based on the comprehensive analysis of the past, present, and future vegetation
patterns in central African forests and savannas, we identify two main policy
relevant findings: (a) mesic savannas are not degraded forests and (b) forests and
savannas have experienced a long history of climate changes and human activity,
which offers insights for their effective management.
Considering that forests and savannas in central Africa offer habitat for biodiversity and contribute manifold to the livelihoods of local communities (see
302
J. C. Aleman and A. Fayolle