Geology and Relief: The unique physical features of Plateau State are its high relief, especially in the north, and its geological
Plateau State Secretariat, Jos
history. The high relief, or more appropriately, the Jos Plateau, provides a hydrological centre for many rivers in northern Nigeria and confers on the northern part of the state a cool climate suitable for livestock rearing and growing of exotic crops. The process of formation of its high relief makes Plateau State one of the mineral rich states in the country.
The Jos Plateau, an erosional relic covering an area of about 7,780 sq.km., is a product of distinct phases of volcanic activities when younger granite rocks extensively intruded into the older basement complex rocks. Each phase of volcanic activities was followed by a long period of weathering and erosion when tin bearing rocks were deposited in the valleys and buried by floods of basalt from subsequent volcanic eruptions.
The landscape of Plateau State rises steeply from 200 metres around the plains of River Benue in the south to an average height of 1,200 metres on the Jos Plateau. There are great peaks like the Shere Hills (1829m), extinct volcanoes and crater lakes on the Jos Plateau which is also the source of great rivers like the Kaduna, Gongola, Hadejia and Yobe.
Climate: Plateau State is characterized by a near temperate climate on the Jos Plateau and a hot and humid climate on its
Mararaba Roundabout, Bukuru
lower parts. Generally, weather conditions are warmer during the rainy season (April-October) and much colder during the harmattan period (December - February). The mean annual temperature in the state ranges between 20°C and 25°C, while the mean annual rainfall figures range from 131.75cm in the southern part to 146cm on the Jos Plateau.
Vegetation: Plateau State falls largely within the northern guinea savannah zone
NASCO Industrial Complex, Jos
which consists mainly of short trees, grasses and the Plateau type of mosaic vegetation. Near some villages are thick hedges of cacti, which have been planted around household farms or compound lands. Fringing woodlands or gallery forests can be found along some river valleys.
Soil: The major soil units of Plateau State belong to the broad category of tropical ferruginous soils, which are much thinner on the high plateau but attain greater depths in the southern part of the state. There are also sizeable pockets of loamy soil of volcanic origin in the high Plateau. These soil groups respond quite well to fertilizers. Soil erosion is a major environmental problem on the Jos Plateau. Tin mining, in its heyday, rendered some localities around Jos, Bukuru, Mangu and Barakin Ladi more susceptible to soil erosion. Today, however, the soil erosion menace is being accentuated largely by over-grazing which has resulted in gullying along the numerous cattle paths which criss-cross the Plateau surface. The soil erosion problem is being tackled through several conservation measures.