Geographical Location
Nzega district is among seven districts of Tabora region. Most parts of the district are located in the northern part of Tabora region, shares borders with Shinyanga rural district in the North, Uyui district in the South, Kahama district to the West and Igunga district on the eastern side. In terms of international identification, the district lies between latitudes 3045’ and 5000’ South of the Equator and between longitudes 32030’ and 33030’ east of Greenwich.
Land Area, Land Use Pattern and Administrative Units
Nzega district has a total land area of 6,961 sq. kms most of which is a rolling plain with very few small hills and escarpments. The land available for agricultural production is 6,343 sq. kms. Out of this arable land of the district, an average of 1,600 sq. kms is cultivated annually, leaving 5,361 sq. kms of useable and unusable land due to rock outcrops and other reasons such as poor soil fertility, soil erosion, river beds and human settlements. About 4,296 sq. kms are either forest reserves or natural forest while land used for grazing covers about 1,065 sq. kms.
Administratively, Nzega District is divided into 4 divisions and 37 wards with a total of 151 villages and 1,010 hamlets distributed unevenly . Nyasa division covers about 33.0 percent of total land area of the district followed by Puge division with about 22.9 percent. Mwakalundi division has the smallest land area in the district constituting only 21.5 percent of the total land area. Bukene division accounts for 22.6 percent of total land area.
Topography, Soils and Climate
Topography
The district forms part of the Central Plateau of Tanzania which is relatively homogeneous with gently undulating plains intersected by seasonally flooded valleybottoms. In the extreme north east this pattern gives way to open flat land suitable for cultivation and covered by well or moderately drained soils of sandy loam texture.
Soils
The soils vary from red lateritic earth grey sand to silt hardpan and iron crust mbuga as shown below:
Rock and very Shallow Soils – These are mostly found on hills with steep slopes though also used for cultivation they are very susceptible to erosion and suitable ideally for grazing and fuel wood production. These soils are found in Itobo, Mizibaziba, Mwakanshahala and Semembela wards;Well – Drained Sandy Soils – Their soil texture is sandy and loamy or coarser within 100 cm of the surface, easily leached and therefore of little intrinsic fertility. They are found in Ikindwa, Shigamba, Mwamala, Mwangoye, Miguwa, Isanzu, Ijanija, Utwigu and Mbogwe wards;
Well – Drained Medium Mixture Soils – Soil colour ranges from red to yellow loamy sand and or clay loam. The soils have greater ability to retain nutrients and therefore are of better potential for agriculture, but need more water. They are found in Puge, Nkiniziwa, Ndala, Karitu, Kasela, Itilo, Tongi, Isanzu and Itobo wards;
Black Clay Soils – These soils are calcareous, which develop cracks on drying and about half are sodic with high fertility and are most suitable for cotton. They are found in Mwakashanhala, Nata, Mbogwe, Miguha, Lusu, Mwangoye and Mwamala wards;
Upland Soils with Impeded Drainage – These soils are easily saturated with water within 100cm of the surface long enough to restrict the range of crops that can be grown. Their textures range from sand to sandy clay, suitable for paddy production. They are to be found in Mogwa, Kahamanhalaga and Igusule wards; and
Mbuga Soils – Mbuga soils include all types of soil in areas where the water table is within 100cm from the surface, which can cause flooding during wet season. They range from sand to clay, of which sandy clay loam and clay are prominent. They are found in Lusu, Nata, Wela, Isanzu, Muhugi, Miguwa, Tongi and Ndala wards. Other places are Mwakanshahala, Ikindwa, Semembela, Igusule and Mwamala wards.
Although the majority of these soils have good nutrient content and are considered suitable for a wide range of food and cash crops and therefore have the potential for profitable cultivation, Nzega district soils can at best be described as moderately fertile.
Climate
The district receives rainfall of between 650mm and 1,200mm annually, falling between the months of October or November and December and a dry period from January to February/March and a second lower peak occurring soon after the dry spell is over in February or March and the rains then tail off in April/May
