2.1. PHYSIOGRAPHY, SOILS AND CLIMATE
2.2. VEGETATION
The country can be roughly divided into four major physiographic classes (Pike and Remington, 1965): the high-altitude plateaus, the medium-altitude plain, the Lakeshore plain and the lower Shire valley. The high-altitude plateaus consist of a number of isolated mountains such as Mulanje, Dedza, Zomba, the Nyika and the Vipya (altitude 1 350 to 3 000 meters). Topography varies from precipitous to undulating, and the soils are mostly lithosols and highly leached latosols. The medium-altitude plain occupies more than 75 per cent of the land surface (altitude 750 to 1 300 meters). The topography is flat to rolling with deep well-drained latosols on the upland sites and poorly drained hydromorphic soils on the lowland sites commonly known as “dambos”. The Lakeshore plain lies along Lake Malawi (altitude 450 to 600 meters). This area is characterized by flat to gently undulating plains. The soils are mostly deep, calcimorphic alluvials and colluvials, with some hydromorphic soils in isolated depressions. The lower Shire valley is a wide rift valley (altitude 35 to 105 meters) and its soils are mostly calcimorphic alluvials with some extensive areas dominated by hydromorphic soils and vertisols.
Malawi’s climate is semi-arid in the lower Shire valley and parts of the Lakeshore, semi-arid to sub-humid in the medium -altitude plain and sub-humid to humid in the high-altitude plateaus.
Two most common vegetation types in Malawi are the miombo woodlands dominated by Branchystegia, Jubernardia and Isoberlinia species, and the Acacia-Piliostigma-Combretum wooded savanna. Both occur mainly in the medium-altitude plain. The high altitude plateaus are dominated by montane grassland vegetation, while the Lakeshore plain and the lower Shire Valley are characterized by a savanna bush-grassland and a thicket with Acacia spp., Sterculia spp., Cordyla africana and scattered Adansonia digitata (baobab) and Hyphaene ventricosa (doum palm).
