Tropical climate regions or tropical grasslands

Location and coverage
These regions are found between 5* and 15’ North and South of the Equator. Tropical regions are well developed in Africa (West Africa, Sudan, East and Central Africa), Brazilian Plateau, Venezuela, and North Australia. In Tanzania, Serengeti grassland is an example of tropical grassland climate region. Figure 2.16 show’s the location of the Savannah climate or tropical climate regions.

Figure 2.16: Savannah climate regions

Climatic characteristics
The Savannah climate is characterised by distinct wet and dry seasons. It also has a high mean temperature throughout the year of between 19“C and 27°C. The annual range of temperature is between 3°C and 8°C. Extreme diurnal range of temperature is one of the characteristics of the Sudan type of climate and the total annual rainfall ranges from 500 millimetres to 1 500 millimetres. Figures 2.17 and 2.18, Tables 2.2 and 2.3 show the climatic data (tropical grassland) for Bulawayo and Cuiaba, which are in tropical climate regions.

Table 2.2: Climatic data for Bulawayo (Zimbabwe)

Figure 2.17: Temperature and rainfall distribution for Bulawayo (Zimbabwe)

Table 2.3: Climatic data for Cuiaba (Brazil)

Figure 2.18: Temperature and rainfall distribution for Cuiaba (Brazil)

Vegetation
In terms of vegetation, this climate is characterised by tall grass often reaching two metres high and scattered trees, which are mainly found near water courses. The vegetation consists mainly of thorny bushes, low shrubs, and thorny trees. They are also characterised by grasslands, which have different names depending on their locations, for example, they are called Campos in Brazil and Savannah in Africa and Australia. Most of the grass tends to turn brownish during the dry season. The roots remain dormant. When the rains come, they produce new shoots and leaves. Additionally, the trees can survive in the dry season in various ways. For instance, some store water in their trunks like the baobab trees and some trees shade off their leaves to prevent loss of water. Moreover, most of the trees have long roots, which can reach the layers of moist soil several metres below the Earth’s surface. Other trees such as Acacia develop an umbrella-­shaped crown, which provides shade around the trunk and roots. This helps to conserve soil moisture.

Economic activities
People in the tropical grasslands engage mainly in the following economic activities:

Crop production: Crops arc of two types: Food and cash crops. Some food crops are maize, millet, beans, rice and groundnuts whereas cash crops include sugarcane, coffee, bananas, cotton, sisal and tobacco. Some crops, for example sisal, cotton, tobacco and sugarcane are grown in plantations.

Generally, agriculture is not that much well developed in the Savannah region, with the exception of river basins where the network of rivers supply water for farming through irrigation. The following reasons arc behind low agricultural development in most of Savannah areas:

Rainfall is unreliable and, in some places, insufficient. Drought incidences existence of pests (example, tsetse-flies), diseases and harmful birds, which harm crops, affect crop production. Moreover, quelea birds affect crop productivity as they fly in huge flocks in search of early maturing cereals, annual wild grass and grains. Rice farms in Mbarali-Mbcya are frequently affected by quelea birds. Furthermore, loss of soil fertility due to scanty vegetation influences soil erosion by allowing the agents of erosion such as wind and water to erode the soil. This affects agricultural production. Soil erosion due to heavy occassional rainfall also affects transport and communication systems due to frequent destruction of infrastructures such as roads, railways and power lines. Crop production is also affected by occasional heavy rains. As this climate region is characterised by sparse population, it hinders crop production due to a shortage of labour.

Livestock-keeping: Another economic activity that is practised in tropical climate regions is nomadic pastoralism, whereby livestock-keepers move from one place to another in search of water and pastures. Extensive grassland (Savannah) provides a good environment for keeping cattle, goats and sheep. A good example can be drawn from the Maasai of East Africa, who mainly engage in livestock-keeping. The Maasai are nomadic. They maintain large herds of cattle, goats and sheep which graze on the grasslands of Kenya and Tanzania. Figure 2.19 shows livestock-keeping in one of the Savannah areas. Sudan is the leading country in livestock-keeping in Africa. It ranks first in Africa for having the largest number of cattle, sheep, goats and camels. Additionally, it is the third country in Africa for poultry production and the fifth country for donkey keeping. In 2019, Sudan’s official sources estimated 41 million cattle, 51 million sheep, 43 million goats and 4.9 million camels. In addition, there were 7.5 million donkeys and 784 thousand horses. In Brazil, the Campos (grassland) are used for rearing cattle for commercial purposes.

Figure: 2.19: Livestock keeping in savannah areas

Hunting and gathering activities: Hunting and gathering activities are also carried out in this area due to the availability of wild animals, birds, fruits, eggs and honey from the forest.

Tourism activities: Tourism is one of the world’s fastest growing industries and a major source of national income, foreign exchange and employment opportunities for many countries. Tourism activities are common in tropical or Savannah climate region because the grassland is home to a variety of exceptional animals such as elephants, giraffes, zebras, leopards, tigers, hyenas, jaguars, lions, buffaloes, rhinos and hippos. In Tanzania, there are many national parks, including world ranking tourist attractions such as the Serengeti, Nyerere, Ruaha, Mikumi and Gombe. Figure 2.20 exemplifies a tourism activity in the Savannah region:

Figure: 2.20: Tourism activity in the Savannah region