Broadleaved
Mainly tree savannah, but also savannah woodland, shrub savannah and cultivated savannah in the centre of Togo, belonging to the lowland "continental" eco-floristic zone (an annual rainfall of 1 100 to 1 300 mm, with three to five dry months). These stands cover a major part of Togo, running from latitude 6° 45´ to 11° N a very extensive ecological zone. Total rainfall varies relatively little throughout the zone, and floristic composition varies according to the length of the ecologically dry season. Population density is very high in some areas so that human impact through fire, cutting and cultivation is widespread, often resulting in a very impoverished and degraded pyroclimax forest.
This savannah, including the parts where plant cover has been degraded through human action, covers about 60% of the country. The same typical woody species are found everywhere, the differences between formations (tree savannah, savannah woodland or shrub savannah) arising solely from the presence or abundance of secondary species. The most common species are Daniellia oliveri and Butyrospermum paradoxum, while Afrormosia laxiflora, Annona senegalensis, Burkea africana, Gardenia ternifolia, Nauclea lancifolia, Pterocarpus erinaceus, Stereospermum kunthianum and Strichnos spinosa are also frequent.
Riparian formations in the Oti valley open forest, palm savannah and seasonally flooded grasslands belonging to the lowland "dry continental" eco-floristic zone. The periodically flooded Oti valley lies in the north-east and is moderately populated (10 to 15 people per km2), mainly by growers of millet, sorghum, bean, groundnut and rice. Its vegetation tends to be highly varied. The patches of forest are not gallery forests in the usual sense of the term, in that they do not necessarily grow along water courses, but tend to be small edaphic formations found on sites with very specific characteristics, particularly deep soils, sometimes flooded, alongside water or with a water table close to the surface. The most common species in these patches of open forest are Khaya senegalensis, Mitragyna inermis, Acacia sieberiana, Parinari excelsa, Prosopis africana, Tamarindus indica, Anogeissus leiocarpus, Balanites aegyptiaca, Mimosa pigra and Terminalia laxiflora. There are large stands of Borassus aethiopium and many small trees (Mitragyna inermis) and shrubs (Mimosa pigra) on wide grasslands that are sometimes flooded with stagnant rain water.
Mainly tree savannah, but also savannah woodland and shrub savannah in southern Togo, belonging to the lowland "dry coastal" eco-floristic zone (an annual rainfall of 800 to 1 100 mm, with three to four dry months). This type is found in the same zone as the previous type. Apart from the degraded forest islands already described, the vegetation is very mixed (with a woody layer and a grassy layer). The savannah of southern Togo has a different composition from that of the centre, with a large amount of Butyrospermum paradoxum and Combretaceae. Some remarkable gallery forests are found within this Sudanian-type savannah, containing a large number of closed-forest species such as Antiaris africana and Cola cordifolia alongside Butyrospermum paradoxum and Acacia campylacantha. However, large parts of these bottomlands suffer considerable pressure from farmers because of their fertile soil, and in many instances the gallery forests are now very degraded. Savannah along roads has suffered degradation, but the human presence is less in the interior. The Sudanian nature of these formations is indicated by the presence of Maytenus senegalensis, Piliostigma thonningii and Stereospermum kunthianum. Riparian formations in the Mono, Haho and Sio valleys, belonging to the lowland "dry coastal" eco-floristic zone. These are the lower valleys of the three rivers of southern Togo, all periodically flooded to varying degrees. A large part of the natural forest cover of these riparian zones has been replaced either by crops, fallow, secondary plant cover or by degraded forest. Some islands of closed intact forest are still left, with edges marked by a band of lianas and shrubby vegetation. Pterocarpus santalinoides, Dialium guineense and Cola laurifolia are the main species within them, and there is practically no undergrowth. Outside these closed stands there are seasonally flooded plains, with thickets of trees and shrubs (Ceiba pentandra, Albizia spp., Spondias mombin, Cola cordifolia, Afzelia africana, Lonchocarpus spp., Triplochiton scleroxylon, Chlorophora excelsa and Mitragyna inermis) situated within grasslands.
"Lions' den" open forest, belonging to the lowland "very dry continental" eco-floristic zone (an annual rainfall of 900 to 1 100 mm, with five to six dry months). The "lions' den" is an alluvial plain in northern Togo, situated at the foot of the cliffs of Dapaong in the north and Nano and Boumbouaka in the south. The "den" is in fact only a part of the plain, but since it was the only part of this zone declared reserved in 1954, it contains a rich and varied plant cover. However, this vegetation is threatened with serious degradation as a result of illicit farming activities, indiscriminate felling of live trees and the permanent presence of a herd of elephants. Its 1 250 ha are crossed by several channels that carry water only during the rainy season. A number of large ponds are also filled with stagnant water on clay soils.
Ficus spp., Syzygium guineense, Daniellia oliveri, Afzelia africana, Lannea welwitschii, Terminalia macroptera and Tamarindus indica are found in the drier parts. Gallery forests are often well developed and contain Khaya senegalensis, Manilkara lacera, Cassia sieberiana, Pentadesma bitira, Raphi spp., Diospyros mespiliformis, Anthocleista nobilis and Vitex spp. Flood-prone and hydromorphic areas especially have a grassy cover of Andropogonae.
A complex of medium-altitude open forest, semi-deciduous forest, savannah woodland, tree savannah and shrub savannah, as well as savannah now heavily under cultivation, belonging to the dry to subhumid medium-altitude eco-floristic zone (300 to 800 m). This type of vegetation more or less covers the Fazao Mountains and the Atakora range (Mounts Siambénou, Defalo, Amato, etc.), as well as a number of mountains north of Lama Kara. These areas tend to have a good rainfall (1 300 to 1 500 mm). However, there is a marked decrease north of the Bafilo Mountains, where the dry season also becomes longer as the effects of the harmattan are felt. This means that the vegetation gets very dry and fires have a more serious impact. The terrain is varied, with plateaux, steep cliffs, depressions and moist ravines. Population density is also varies greatly. The Fazao mountain region is the most sparsely populated in Togo (with less than 6 persons per km2), with vast, uninhabited, almost inaccessible areas, whereas the Atakora region, the Lama chain and some parts of the Bafilo Pewa Mountains are densely populated, and hence denuded and degraded, with consequent major erosion.
The zone is covered by a mosaic of different formations, ranging from patches of semi-deciduous forest in the Bafilo, Malfakassa and Fazao Mountains, which account for only a small part of the plant cover, to scattered grassy cover. Open forest predominates, with Afzelia africana, Anogeissus leiocarpus and Isoberlinia doka. Semi-deciduous forest, mainly in the form of gallery forests, contains Dialium guineense, Antiaris africana and Berlinia grandiflora. Medium-altitude savannah (woodland, tree or shrub) contains Monotes kerstingii, Isoberlinia doka and Uapaca somon.
last updated: Wednesday, October 6, 2004
