use change. We start by reviewing the vegetation changes since the Last Glacial
Maximum (approximately 21,000 years ago), and assessing the current distribution
of major vegetation types in relation to different drivers, mainly related to climate
and fire regimes. We then project future vegetation cover based on rainfall variability
and agricultural activity, using different scenarios. Section 9.2 outlines the main
historical milestones shaping vegetation change in central Africa, and the main data
collection and analysis approaches. Section 9.3 highlights the main past (Sect.
9.3.1), current (Sects. 9.3.2), and future (Sect. 9.3.3) vegetation changes, and their
drivers. Section 9.4 synthesizes the main findings and discusses some of the main
policy implications for restoring ecosystems, expanding protected areas, and designing sustainable forest management approaches in the region.
9.2 Methodology
9.2.1 Central Africa and Its History
9.2.1.1 Study Area
This chapter focuses on vegetation changes in central Africa, an area that covers the
Congo Basin, and adjacent savannas and woodlands (including the Miombo). For
practical reasons, the study area is defined by the boundaries of Cameroon, the
Central African Republic (CAR), the Democratic Republic of Congo (DRC), Equatorial Guinea, Gabon, and the Republic of Congo, and spans more than 4 million
km
2 . According to the Tropical Rainfall Measuring Mission (TRMM, Nicholson
et al. 2003), the environmental conditions vary widely across this vast study area.
Mean annual rainfall ranges between 440 and 3220 mm, from the driest sites in
North Cameroon to the wettest sites in the Coast of Cameroon.
The distribution of forests and savannas in this area is the legacy of a long history
of climate changes and human impacts. Table 9.1 summarizes the main periods of
climate and vegetation changes since 21,000 cal yr BP (i.e., calibrated years before
present, the present being 1950 by convention).
9.2.1.2 Paleo-History
Paleo-environmental reconstructions
4 suggest that central Africa has experienced a
succession of dry and humid periods, with tropical forests contracting or expanding
in response (Maley 1989, 1996; Vincens et al. 1999).
5 The Last Glacial Maximum
4 Paleoenvironmental reconstructions entail the reconstruction of past vegetation, climate and
disturbances using bio-proxies (e.g., pollen, phytoliths, diatoms, charcoal particles) and the biogeochemical analysis of natural archives (e.g., sediments or paleosols).
5 In comparison the Amazon remained much more stable during the same period (Anhuf et al. 2006).
9 Long-Term Vegetation Change in Central Africa: The Need for an Integrated. . .
285
Maximum (approximately 21,000 years ago), and assessing the current distribution
of major vegetation types in relation to different drivers, mainly related to climate
and fire regimes. We then project future vegetation cover based on rainfall variability
and agricultural activity, using different scenarios. Section 9.2 outlines the main
historical milestones shaping vegetation change in central Africa, and the main data
collection and analysis approaches. Section 9.3 highlights the main past (Sect.
9.3.1), current (Sects. 9.3.2), and future (Sect. 9.3.3) vegetation changes, and their
drivers. Section 9.4 synthesizes the main findings and discusses some of the main
policy implications for restoring ecosystems, expanding protected areas, and designing sustainable forest management approaches in the region.
9.2 Methodology
9.2.1 Central Africa and Its History
9.2.1.1 Study Area
This chapter focuses on vegetation changes in central Africa, an area that covers the
Congo Basin, and adjacent savannas and woodlands (including the Miombo). For
practical reasons, the study area is defined by the boundaries of Cameroon, the
Central African Republic (CAR), the Democratic Republic of Congo (DRC), Equatorial Guinea, Gabon, and the Republic of Congo, and spans more than 4 million
km
2 . According to the Tropical Rainfall Measuring Mission (TRMM, Nicholson
et al. 2003), the environmental conditions vary widely across this vast study area.
Mean annual rainfall ranges between 440 and 3220 mm, from the driest sites in
North Cameroon to the wettest sites in the Coast of Cameroon.
The distribution of forests and savannas in this area is the legacy of a long history
of climate changes and human impacts. Table 9.1 summarizes the main periods of
climate and vegetation changes since 21,000 cal yr BP (i.e., calibrated years before
present, the present being 1950 by convention).
9.2.1.2 Paleo-History
Paleo-environmental reconstructions
4 suggest that central Africa has experienced a
succession of dry and humid periods, with tropical forests contracting or expanding
in response (Maley 1989, 1996; Vincens et al. 1999).
5 The Last Glacial Maximum
4 Paleoenvironmental reconstructions entail the reconstruction of past vegetation, climate and
disturbances using bio-proxies (e.g., pollen, phytoliths, diatoms, charcoal particles) and the biogeochemical analysis of natural archives (e.g., sediments or paleosols).
5 In comparison the Amazon remained much more stable during the same period (Anhuf et al. 2006).
9 Long-Term Vegetation Change in Central Africa: The Need for an Integrated. . .
285