Sudanian Dry Forest
The few remaining examples of these forests are often confined to deep ravines with some of the best examples in the sandstone areas of western Mali. They are dominated by either Gilletiodendron glandulosum or Guilbourtia copallifera, but these two evergreen species rarely occur together. Forests of the former appear to be largely confined to this BioProvince.
Sudanian Riparian Forest
The riparian and swamp forests of this BioProvince are characterized by semi-evergreen species, which in southern areas mainly include Syzygium guineese subsp. guineese, Vitex doniana and the endemic Khaya senegalensis (Meliaceae) and Terminalia glaucescens (Combretaceae). In the north the main species include Acacia sieberana, Diospyros mespiliformis, Ficus sycomorus, Tamarindus indica and the endemic Ficus glumosa (Moraceae). Floodplains provide another important habitat for wet woodland. Along the River Arum (Jebel Marra) these areas include an Acacia albida association in which endemic species such as Prosopis Africana (Fabaceae), Pseudocedrela kotschyi (Meliaceae) and Terminalia laxiflora (Combretaceae) occur, while the clay depressions subject to seasonal flooding provide habitat for species such as Acacia nilotica subsp. nilotica and the endemic Mitragyna inermis (Rubiaceae).
Sudanian Adansonia Forest
Forests or woodland characterized by Adansonia digitata, Celtis integrifolia and the endemic Parkia biglobosa (Fabaceae) are typically found in areas where woodland gives way to savanna or where there are woodland - savanna mosaics. Good examples can be found at Bandia near Thies.
Sudanian Deciduous Savanna Forest
In these open forests the endemic Anogeissus leiocarpus (Combretaceae) is often the main species together with Albizia amara subsp sericocephala, Terminalia brownii and other endemic species such as Combretum glutinosum (Combretaceae), Isoberlinia doka (Fabaceae) and Khaya senegalensis (Meliaceae). In some of the dryer Anogeissus forest, such as in the Zamfara Forest Reserve west of Katsina in Nigeria, the principal tree species include a variety of additional endemic species among the dominant trees such as Albizia chevalieri (Fabaceae), Boswellia dalziellii (Burseraceae), Butyrospermum paradoxum (Sapotaceae), Lonchocarpus laxiflorus (Fabaceae), Piliostigma reticulatum (Fabaceae), Prosopis africana (Fabaceae), Sclerocarya birrea (Anacardiaceae) and Terminalia avicennioides (Combretaceae). The same is also true at the wetter end of the spectrum such as on the sandy plateau in the Yankari Game Reserve. Here endemic species such as Afzelia africana (Fabaceae), Combretum nigricans (Combretaceae) and Pericopsis laxiflora (Fabaceae) are likely to be encountered. A somewhat different composition occurs in the wooded grasslands at the edge of grassy floodplains (fadamas) where the characteristic trees include the endemic species Daniellia oliveri (Fabaceae) and Pseudocedrela kotschyi (Meliaceae). Also, in the extreme east of the BioProvince, close to the frontier with Ethiopia there is a narrow strip of dark clay on sloping ground where Anogeissus leiocarpus shares dominance with Combretum hartmannianum. These woodlands include the sporadic appearance of the endemic tree Sterculia setifera (Malvaceae).
Sudanian Semi-Desert Scrub
The main scrub species found in the arid areas include Acacia tortilis subsp. tortilis, Leptadenia pyrotechnica and Salvadora persica on the lithosols, whereas on the clay soils Acacia mellifera, Balanites aegyptiaca, Capparis decidua and Ziziphus spina-christi are the main species. Rocky outcrops such as the inselbergs on the Jos Plateau and the sandstone of western Mali support different assemblages of species that can be broadly desribed as rupicolous scrub. The sandstones, for example, support a stunted Guibourtia copalifera community with associated species such as Boscia salicifolia, Combretum collinum, Ficus lecardii, Gardenia sokotensis, Hexalobus monopetalus, Spondias mombin, Zanha golungensis and the endemic Bombax costatum (Malvaceae) and Euphorbia sudanica (Euphorbiaceae).
Sudanian Grassland
In the lowlands, grasslands are usually dominated by various Aristida species on lithsols, while Schoenefeldia gracilis and Sehima ishaemoides are the main species on clay soils. Other species become dominant in upland grasslands. For example, on the volcanic ash slopes of Jebel Marra, Andropogon distachyas together with Hypaurhenia hirta and Themeda triandra are some of the more characteristic species. These grassy slopes also provide habitat for various perennial herbs such as Campanula edulis, and the endemic Felicia dentata subsp. nubica (Asteraceae) and Kickxia aegyptiaca subsp. virgata (Fabaceae). On the flatter areas and upland plains a type of meadow can be found dominated by the attractive, golden-headed Hypaurhenia multiplex. These grasslands are made additionally colourful by the reddish-purple flowers of Geranium ocellatum and Erodium malacoides, the electric-blue Cyanotis barbata and the white, woolly capitula of the endemic Gnaphalium marranum (Asteraceae). Other species include orchids such as Habenaria filicornis, H. humilior and Satyrium coriophoroides.
Further information required.
References
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