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4 Google Earth (Landsat/Copernicus) view of Bicuar National Park. Note deforested margins (pale to white) around its borders. Also, note the light lines of the grassy mulolas
Source publication
The Savanna Biomes (Mesic/Dystrophic and Arid/Eutrophic) of Angola cover over 90% of the country. This Chapter presents the case for the recognition, across Africa, of these two distinctive savanna biomes, both defined by the co-dominance of fire-tolerant trees and C 4 grasses, falling within seasonal climates of warm, wet summers and mild, dry win...
Contexts in source publication
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... good example of pattern is found in Bicuar National Park in Huíla (Fig. 14.4). The border of Bicuar is clearly delineated along its northern boundary, where deforestation has left a treeless belt of pale sands, contrasting with the dark, thickly wooded landscapes protected within the park. A dendritic pattern, like lines on a fingerprint, results from alternating wooded and grassy belts. This is a sequence of ...
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... of the higher ground are occupied by Baikiaea woodland and Combretum thickets. Towards the margins of the higher ground, deeprooted Brachystegia woodland transitions into a narrow fringe of Burkea woodland followed by a belt of shallow-rooted Terminalia savanna. These are found on the pale white sands at the margin of the convex slopes ( Fig. 14.6). The lateral spread and shallow rooting of Terminalia in the oxygenated topsoil possibly accounts for its ability to grow in the seasonally waterlogged sands. During the rains, a perched water table results in a seasonal seepline below the Terminalia belt, with a fine flow of water from these white sands. This is followed by open ...
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... the valley soils are seasonally waterlogged, preventing tree growth. Seasonal waterlogging is revealed in the subsoil by blue and orange mottling and gleying. In some catenas, the valley bottom might include a small pool (tala) or a narrow line of forest trees (muxito), where erosion has created better-drained conditions suited to tree growth (Fig. 14.7). ...
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... hard sclerophyll leaves) of the plant species that colonise the Macrotermes mounds. The termites thus create a nutrient-rich hotspotan ecosystem of its own making which contributes to the wider range of plant species that occupy the rich soils of the mound, and to the many species of animals that are dependent on the system (Malaisse, 1978; Fig. 14.9). From Malaisse (1978) Far more abundant are the diverse structures, both above and below ground, of humus and soil-feeding Cubitermes and Trinervitermes, often built on seasonally waterlogged soils (Figs. 14.10, 14.11). These are especially abundant in Wet Miombo. In Shaba, DRC, they have a biomass twice that of the Macrotermes and ...
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... plant species that occupy the rich soils of the mound, and to the many species of animals that are dependent on the system (Malaisse, 1978; Fig. 14.9). From Malaisse (1978) Far more abundant are the diverse structures, both above and below ground, of humus and soil-feeding Cubitermes and Trinervitermes, often built on seasonally waterlogged soils (Figs. 14.10, 14.11). These are especially abundant in Wet Miombo. In Shaba, DRC, they have a biomass twice that of the Macrotermes and build their nests with their faecal matter, comprising soil particles and digested humus, creating local concentrations of nutrients at a finer spatial scale than the Macrotermes mounds, depleting the organic matter of ...
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... stems and branches to short shoots which produce leaves, flowers and fruits immediately after the passage of the frequent fires that sweep across miombo ecosystems (Fig. 14.12). Geoxyles invest their woody growth in underground rootstocks (lignotubers or xylopodia), often with a dense network of rhizomes and roots that can cover over 50 m 2 (Fig. 14.13). They thus place their regenerative organs underground for most of the year to protect them from damage by fire, frost or herbivory ( Figs. 14.14, 14.15 and 14.16). The first scientist to describe the geoxyle habit was pioneer Danish ecologist Eugen Warming. Working in the cerrado of Brazil (the South American equivalent of miombo) in ...
