Central Zambezian Wet Miombo Woodlands

Termites are abundant in this woody, biomass rich habitat, and by concentrating organic matter and nutrients in their mounds, termites produce nutrient-rich patches within an otherwise nutrient-poor landscape. The poor soils and harsh dry season favour large-bodied generalist animals including African bush elephant, African buffalo, and previously black rhino. The ecoregion occupies the Central African Plateau at altitudes between 1,000 and 1,600 m, with a few localized areas of higher relief, such as Mount Mulumbe in southern Democratic Republic of Congo.

The ecoregion covers about 70 percent of central and northern Zambia, the southeastern third of DRC, western Malawi, much of western Tanzania, and parts of Burundi and northeastern Angola. Valleys of major rivers such as the Limpopo, Zambezi, Shire, as well as the upper Congo River drainage dissect the plateau. Over tens of millions of years they have been eroded and weathered into a low relief peneplain, with inselbergs projecting from the surface. Rainfall is unimodal, concentrated during the hottest months of November through March/April. 

A pronounced drought occupies the cooler season, lasting up to 7 months. Rainfall is typically between 1,000 and 1,200 mm annually, with up to 1,400 mm falling at higher elevations. Mean maximum temperatures range between 24–27°C, depending on altitude. Mean minimum temperatures range from 9° to 18°C.

Trees of the legume subfamily Caesalpinioideae, particularly from the genera Brachystegia, Julbernardia and Isoberlina, dominate. Frequent canopy dominants of the miombo tree species includes Brachystegia floribunda, B. glaberrima, B. taxifolia, Julbernardia globiflora, J. Paniculata, and Isoberlina angolensis.

This ecoregion is a part of the Zambezian regional centre of endemism and has the highest floral richness of the African miombo ecoregions, with the peak of miombo plant species richness in Zambia. The ecoregion may support over 3,000 plant species, with perhaps several hundred endemics, including members from the genera Crotalaria, Indigofera, and Brachystgia. 

There is a low density of large mammals, attributed to the harsh dry season, long droughts, and poor soils, which results in vegetation of low nutrient content – ideal conditions for elephant and African buffalo. Other species make more use of non-miombo habitats, including sable antelope, roan antelope, Lichtenstein’s hartebeest, and southern reedbuck. Rates of mammal endemism are low, with three strict endemics: Rosevear's striped grass mouse and two white-toothed shrews, Ansell’s shrew and Upemba shrew. Threatened species include lions, cheetahs, and African wild dogs. The only strict avifauna endemics are Ruwet’s masked weaver and black-faced waxbill.

Throughout the ecoregion, stands of pristine miombo have been cleared or heavily modified in the past, and then regenerated. The ecoregion has an extensive protected areas network and of the national parks, two are particularly important: Kafue in Zambia and Upemba National Park in southern DRC. Lufira Biosphere is a newly appointed Biosphere Reserve in DRC. Other national parks include Nyika and Kasungu in Malawi, Mahale Mts. In Tanzania, and Lusenga Plain in Zambia. There are no protected areas in Angola.

Cutting woody vegetation for the production of charcoal, especially close to major roads and large urban centres, is having a marked impact. Large-scale cultivation is uncommon, but subsistence agriculture is practiced by most of the population. Growing staple and cash crops such as maize, cassava, sorghum, millet, and tobacco has converted significant areas. 

Growing tobacco for export has led to large losses of miombo in Tanzania and Malawi for both cultivation and fuelwood. In Zambia, “citimene,” a traditional form of ash-fertilizing agriculture is also practiced and increased human populations mean that this is no-longer sustainable. Although fire is an integral part of miombo ecology, human setting of fires is believed to have increased the frequency of fire far above the natural level. Repeated late-season fires in many areas have decreased forest regeneration, seed germination, and seedling survival growth can be severely disturbed. 

Poaching and illegal hunting for bushmeat have a significant impact on the wildlife throughout the ecoregion. Elephant and rhino poaching, in particular, have been extremely severe. The live animal trade in Tanzania is one of the biggest in Africa, especially in birds, reptiles and tortoises. 

The priority conservation actions for the next decade will be to: 1) promote and support the introduction of locally produced renewable energy, for example, bio-energy, solar energy and wind; 2) support and build capacity of the community based natural resource programs; and 3) increase livestock production to reduce the price of domestic meat whilst at the same time increasing protection of protected areas through ground enforcement in order to reduce poaching.

Citations 

1. Burgess, N., Hales, J.A., Underwood, E., Dinerstein, E., Olson, D., Itoua, I., Schipper, J., Ricketts, T. and Newman, K. 2004. Terrestrial ecoregions of Africa and Madagascar: a conservation assessment. Island Press.
2. World Wide Fund for Nature. 2012. Miombo Eco-region ”Home of the Zambezi” Conservation Strategy: 2011-2020. Harare, Zimbabwe: World Wide Fund for Nature.
3. Martin, A., Caro, T. and Mulder, M.B. 2012. Bushmeat consumption in western Tanzania: a comparative analysis from the same ecosystem. Tropical Conservation Science. 5(3), pp.352-364.
4. Frost, P.G.H., Timberlake, J.R. and Chidumayo, E. 2002. Miombo-mopane woodlands and grasslands. Wilderness: Earth’s last wild places. pp.183-204.