Formations in the -Inhambane BioProvince

Peter Martin Rhind

Zanzibar-Inhambane Deciduous Forest Dry deciduous forests occur scattered along the entire length of north of Massinga. They are characterized by trees such as Adansonia digitata, Afzelia quanzensis, Balanites maughamii, Chlorophora excelsa, africana, Khaya nyasica, Millettia stuhlmannii, Pteleopsis myrtifolia, Sterculia appendiculata and the endemic Dialium mossambicense (), Fernandoa magnifica (Bignoniaceae) and Inhambanella henriquesii (Sapotaceae). Other endemic trees include Acacia robusta subsp. usambarensis, (Fabaceae), Cassipourea mossambicensis (Rhizophoraceae), Dolichandrona alba (Bignoniaceae), Grewia conocarpa (Tiliaceae) and Pleioceras orientala (). The sub-canopy is usually well developed and often forms a thick almost impenetrable layer of deciduous and semi-deciduous shrubs including the endemic Salacia orientalis (Celastraceae). There is a form of semi-deciduous forest mainly confined to the sublittoral belt of ancient dunes, but its floristic composition varies considerable. Some of the more characteristic species include Celtis africana, Dialium schlechteri, Morus mesozygia, Trachylobium verrucosum and the endemic or near endemic Cola mossambicensis (Sterculiaceae) and Pseudobersama mossambicensis (Meliaceae).

Zanzibar-Inhambane Miombo Woodland This, the most extensive type of woodland in the BioProvince, is represented by a floristically impoverished version of Miomba dominated by various species of Brachystegia and Julbernardia globiflora. For example, Brachystegia spiciformis woodland is extensively developed on ‘Sol do Save’ sublittoral sand dunes between the Sabi and Limpopo rivers. Some of the endemic species found in these woodlands include the trees Carpodiptera africana and Grewia transzambesica (Tiliaceae), the shrubs Maerua scandens (Capparidaceae) and Tetracera boiviniana (Dilleniaceae) and the perennial herb Jatropha scaposa ().

Zanzibar-Inhambane Scrub Forest Scrub forest dominated by Diospyros cornii and Manikara mochisia occurs in the interior parts of the BioProvince in and southern Somalia. The lower canopy is characterized by Bivinia jabertii, Croton pseudopulchellus, Diospyros consolatae, Euclea natalensis, Excoecaria venenifera, Haplocoelum foliosum, Ochna thomasiana, Sideroxylon inerme, Thespesia danis, Thylachium africanum, Xeromorpha nilotica and the endemic Grandidiera boivinii (Flacourtiaceae) and Suregada zanzibarensis (Euphorbiaceae). Climbers and epiphytes, however, are almost absent, and apart from a few stands of Sanseviera, few species occur in the herb layer.

Zanzibar-Inhambane Bushland and Thicket Where unfavourable soil conditions prevent the development of forest, various types of bushland and thicket have developed. On the coral limestone in parts of Kenya, for example, a climax evergreen thicket characterized by Haplocoelum inoploem, Harrisonia abyssinica, Lannea stuhlmannii, Ludia mauritiana, Monikara sansibarensois, Millettia usaramensis, Monanthotaxis fornicata, Pycnocoma littoralis, Sterculia rhynocarpa, Uvaria leptocladen and the endemic Cussonia zimmermanii (Dichopetalaceae) and Suregada zanzibarensis (Euphorbiaceae) is one of the main types of thicket. Other endemics found in evergreen thicket, particularly coastal thicket, include the shrubs Dichapetalum aureonites (Dichapetalaceae) and Ochna beirensis (Ochnaceae) and the climber Traspis Copyright © 2010 Peter Martin Rhind mosambica (Malpighiaceae). Also in the coastal zone, especially in the area between Nacada and Mucojo in Mozambique, a thicket largely composed of deciduous species occurs. The characteristic species include Bathia macrocalyx, Dichrostachys cinerea, Combretum pisoniiflorum, Gossypioides kirkii, Guilbourtia schliebenii, kirkii, Mimosa busseana, Platysepalum inopinatum, Pseudoprospis euryphylla and the endemic Dialium mossambicense. It is also characterized by the presence of scattered tall trees such as Manikara altissima and the endemic Bombax rhodognapholon (Bombacaceae). Other endemics generally associated with coastal bush and thicket include the shrubs Capparis lilacina, C. orthocantha (Capparidaceae), Commiphora serrata (Burseraceae), Ochna angustata (Ochaceae), Vernonia inhacensis (Asteraceae), the herbaceous forb Diplocyclos tenuis (Cucurbitaceae) and the grass Cenchrus mitis (Poaceae).

Zanzibar-Inhambane Coastal Dune Vegetation The coastal dunes of this BioProvince normally include a pioneer zone of sand binding species that eventually creates conditions suitable for a dune thicket. This in turn slowly allows the development of dune forest. Along the Mozambique coast the main pioneer species are Canavalia maritima, Cyperus maritimus, Dactyloctenium aequptiacum, Ipomoea pes-caprae, Launaea sarmentosa, Scaevola thunbergii, Sesuvium portulacastrum, Sophora tomentosa, Sporobolus virginicus, Tephrosia canescens and the endemic Sophora inhambanensis. Other endemic species associated with these dunes are the shrubs Cussonia arenicola (Araliaceae) and Fagara schlecteri (Rutaceae), and the herbaceous species Cleome stricta (Capparidaceae), Hermannia micropetala (Sterculiaceae), Polygala francisci (Polygalaceae) and Tricliceras lanceolatum (Turneraceae). Moving landward into the dune thicket zone there is a degree of variation in species composition. In southern Mozambique there is often a dense low cover of the endemic bush Grewia occidentalis var. littoralis (Malvaceae), while in more southerly areas Mimusops caffra is usually the dominant shrubby species. The endemic species of these coastal thickets include the shrubs Elaeodendron fruticosum (Celastraceae) and Memecylon sessilicarpum (Melastomataceae), the climber Triaspis suffulta (Malpighiaceae), and the perennial herbs Krauseola mosambicina (Caryophyllaceae) and Spermacoce schlecteri (Rubiaceae). With increasing stabilisation species such as Apodytes dimidiata, Brachylaena discolor, Bridelia schlecteri, Clerodendron glabrum, Commiphora schlecteri, Ochna natalitia, Ozoroa obovata and Vepris lanceolata become more important. In some cases these have developed into dense evergreen forests rich in climbers and such as Maclura africana, Popowia caffra, Rhoicissus revoilii, Sarcostemma viminale, Uvaria gracilipes and the endemic Cissus quadrangularis (Vitaceae), while other endemic species of these dune forests include the shrubs Allophylus mossambicensis (Sapindaceae) and Jatropha subaequiloba (Euphorbiaceae).

Further information required.

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Copyright © 2010 Peter Martin Rhind