Botanical surveys in Angola
Tim in Cuando Cubango Province
Angola is a large country. Its land area is over 1 million square kilometers. As a result of its vast size and its particular history, plants have been poorly documented scientifically over much of the country. I recently visited the valleys of two major rivers in the south of the country, in Cuando Cubango Province. While there have been some recent scientifically documented surveys in other parts of Angola, the last major scientific plant collecting expedition to Cuando Cubango Province was in 1899, when Pieter van der Kellen led the ‘Cunene-Zambezi Expedition’ during which the plant collector Hugo Baum made over 1000 collections of pressed plants.
Periods of arid climate thousands of years ago have resulted in the landscape in southern Angola being covered in sand, sometimes to a considerable depth. The most common type of vegetation in this southern part of Angola is woodland.
The focus of the expedition I was involved with in Cuando Cubango Province was to document the biodiversity seen in and around the large rivers in this province. These rivers flow into other countries, and especially into the popular tourist destination of the Okavango delta in Botswana. So the conservation status of the species around these rivers has implications for conservation in surrounding countries. The expedition was coordinated by the Southern African Regional Environment Program.
The authorities in Angola have recently designated an area in the south-east corner of the country as a national park. They have been investigating whether other sites across Angola would be suitable for designation as national parks in the future. The fieldwork that I was involved in will establish a baseline checklist of the plant species seen in potential national park sites that could be used to inform the decision process. Along with other botanists at Kew, I have been identifying the specimens that we shipped to Kew. We identify specimens by examining Floras and other literature and comparing the specimens to the collections that Kew holds in its Herbarium. Some of the plants that I collected in Angola have not been recorded from Angola before.
David on the shores of Lagoa Carumbo
Meanwhile, almost 1000 km to the north of this survey area, my colleague David was busy compiling species inventories for each of the habitats in an area around the largest freshwater lake in the country – Lagoa Carumbo. David travelled and worked alongside another Kew colleague, Iain Darbyshire.
As a near-pristine environment, untainted by sedimentation of the rivers caused by small-scale illegal diamond mining that blights neighbouring river valleys, this is another area for which the Ministry of the Environment needs evidence before formally proposing it as a protected area for conservation.
Like the south-east of Angola, the Carumbo area is also overlain by deep deposits of Kalahari sand. But as the rainfall in this part of the country is high (c. 1400 mm per year), the vegetation is very different. Seasonally burned savanna grasslands extend across the plateau as far as the eye can see, and where the rivers have cut down to the base of the deposits, there are fingers of pure Congo rainforest and associated wetlands – a unique mosaic of habitats. Already the team has documented around 60 species not formerly recorded from the country, and identified 13 species that are possibly new to science.
David and colleagues from the Ministry were able to visit the regional museum in Dundo, set up in the early 20th century, which is famous for its enthnographic and biological collections. And in a nearby park, they managed to relocate a statue of Kew-trained Swiss botanist John Gossweiler who had worked in the area in the late 1940s.
After Friedrich Welwitsch, famous of course for the living fossil bearing his name, Gossweiler was the most significant figure in Angolan botany, and is portrayed entering plant collection details into his botanical notebook, just as we were doing ourselves earlier in the trip.
- Tim Harris -
- Online checklist of plants for Angola
- Assessing Plant Conservation Priorities in Angola
- Botanical survey doubles the known flora of Lunda Norte, Angola
for plant collectors who have worked in Angola:
Collector: Grandvaux Barbosa
Lobin, W. (1984). L.A. Grandvaux Barbosa (1914-1983). Courier Forschungsinstitiut Senckenberg 68: 201-203.
Figueiredo, E., Soares, M., Siebert, G., Smith, G.F. & Faden, R.B. (2009). The botany of the Cuneni-Zambezi Expedition with notes on Hugo Baum (1867-1950). Bothalia 39: 185-211.
Warburg, O. (1903). Kunene-Sambesi-Expedition. Kolonial-Wirtschaftliches Komitee. Berlin.
Polhill, R.M. (1980). Helen Faulkner (1888-1979). Kew Bull. 34: 619.
Exell, A.W. (1952). John Gossweiler. Taxon 1: 93-94.
Fernandes, A. (1954). John Gossweiler (1873-1952). Vegetatio 4: 334-335.
Martins, E.S. (1994). John Gossweiler. Contribuiçâo da sua obra para o conhecimento da flora angolana. Garcia de Orta, Sér. Botânica 12: 39-68.
Hoffmann, O. (1880). Plantae Mechowianae. Linnaea 43: B9
Hiern, W.P. (1896-1901). Catalogue of the African plants collected by Dr Friedrich Welwitsch in 1853-1861. British Museum (Natural History). London.
Rendle, A.B. (1899). Catalogue of the African plants collected by Dr Friedrich Welwitsch in 1853-1861. Vol. 2(1). British Museum (Natural History). London.
Stearn, W.T. (1973). Catalogue of the African plants collected by Dr Friedrich Welwitsch (1853-1861) and his litigous background. Garcia de Orta, Sér. Botânica 1: 101-104.