Lettowianthus stellatus, collected in Mahenge, a limestone plateau area in the Ulanga District, Morogoro Region, Tanzania. The species is known only from Tanzania and Kenya.

Tanzania is among the African countries with the highest levels of biodiversity, largely due to an exceptional variability of topography and climate that has given rise to a wide variety of habitats for plant and animal species. With an estimated 11,000 species of higher plants and a land area of 885,800 km², Tanzania is home to about 37 percent of the plant species of tropical Africa in less than 5 percent of its area.

Tanzania contains parts of two major Biodiversity Hotspots: the Coastal Forests of Eastern Africa Hotspot, which extends northward through Kenya to Somalia and southward to coastal Mozambique; and the Eastern Afromontane Hotspot, which extends from Saudi Arabia in the north to Zimbabwe and Mozambique in the south and in Tanzania includes the mountains of the Albertine Rift, the geologically recent northern volcanics, the ancient crystalline mountains of the Eastern Arc, and the extensive Southern Highlands of Tanzania. While Tanzania has about 44 million human inhabitants, its population density is not particularly high compared to that of many African countries. However, the population is concentrated primarily in the areas with the highest numbers of rare and endangered species, including parts of the above-mentioned Hotspots, creating a conservation concern out of proportion to the overall population density.

Lumuma Valley, looking west from Morogoro Region, Kilosa District, to the Rubeho Mountains in Dodoma Region, Mpwapwa District, central Tanzania

Quartzite spires at Issongo, south of Mahenge, Morogoro Region, Ulanga District, central Tanzania

The Missouri Botanical Garden (MBG) has conducted botanical research in Tanzania for more than 25 years. From the early 1980s to the mid-1990s, MBG focused principally on botanical inventory in areas of high plant diversity, mostly within the Eastern Arc Mountains and the Southern Highlands. From 1987 to 1995 MBG collected plant samples for anti-tumor and anti-HIV screening in a number of areas already under inventory efforts, but also expanded these activities into several new areas, including the northern volcanics. From 1997 to 2000, MBG collaborated with the National Herbarium of Tanzania (NHT) to conduct the Tanzania Botanical Training Programme, which, working within the framework of existing environmental organizations, trained 18 resident botanists, more than half of whom are still employed in positions that make use of the skills they learned. Since 2000, MBG and NHT have expanded their collaboration to form the Tanzania Botanical Research and Conservation Programme, through which all of MBG’s conservation-related activities in East Africa operate.

Three current projects target the inventory and conservation of East African biodiversity, including parts of its Biodiversity Hotspots. MBG and the International Union for Conservation of Nature (IUCN) are conducting a global Red List assessment of 1,743 plant species in the Eastern Arc Mountains and Coastal Forests of Tanzania and Kenya. MBG, the African Conservation Centre, and the University of York are studying the effects of climate change on plant biodiversity and human livelihoods in East Africa, with a central focus on the bi-national area along the border of Kenya and Tanzania. MBG and the Wildlife Conservation Society Tanzania Programme have recently initiated the inventory and conservation assessment of the plants of the Southern Highlands of Tanzania.

Alangium chinense (Cornaceae), Rungwe Forest Reserve, Mbeya Region, Rungwe District, southwestern Tanzania

Begonia poculifera (Begoniaceae), Nawenge Forest Reserve, Morogoro Region, Ulanga District, central Tanzania

MBG’s program in Tanzania has four major goals:

District Forester Octavian Nkawamba with Bersama abyssinica (Melianthaceae), Nawenge Forest Reserve, Morogoro Region, Ulanga District, central Tanzania

For more information, contact
Roy Gereau

Learn more about the Missouri Botanical Garden’s program in Africa and Madagascar