Physical Features

A MAP SHOWING PHYSICAL FEATURES IN UGANDA

Uganda has many different physical features. Physical features refer to land forms that make up the shape of the land on the earth's surface. These include mountains, rift valley, plateaus, rivers, lakes and plains.

 Activity

Activity

Use the map on page 13 to answer the questions below.

1. List examples of physical features found in Eastern Uganda.

2. Which lakes are found in the rift valley?

3. Identify any two physical features found in your district

Plateaus

These are flat, raised areas of land. Plateaus are different from Plains in that they rise steeply from the land around them. An example of a plateau in Uganda is the North West areas of West Nile covering the districts of Nebbi, Arua and Amuru. They 
range from 350m at the western border to 1300m. More plateau areas stretch around the hills of Kampala such as Muyenga, Nakasero, Rubaga, Mengo and Old Kampala and 
Some parts of Mukono district all found in Central Uganda.

Mountains

Mountains rise high above the surrounding land, often showing a beautiful scenery and view from the top. The highest mountain in Uganda is the Rwenzori mountains in Western Uganda with the highest peak called Margherita (5110 metres above sea level). Mountains vary greatly in size and how they are formed. The two main types of mountains are volcanic and fault block.   

Other mountains in Uganda that rise above 3000 metres above sea level include:- Mount Elgon in the East (4321 metres above sea level) Mount was originally, known as Mount Masaba. The Mufumbiro ranges is 4127 metres in South Western Uganda, Its peak is Muhavura. It borders Rwanda and The Democratic Republic of Congo. Moroto Mountain (3084 metres) is found in the North Eastern Uganda.

The Western rift valley 

Formation of different physical features 
Volcanic mountains. 

Mount Elgon and Mufumbiro mountain ranges are some of the volcanic mountains in Uganda. Volcanic Mountains as the one Shown in the formation, formed when Molten rock materials reached the surface through a weak area on the earth's crust.

Some mountains are still, active such as Mt. Mufumbiro that is, they can erupt any time while others are dormant because they have taken a long time without erupting. There are mountains which are said to be dead volcanoes such as Mt. Moroto.

 Activity

If you wanted to know whether a particular mountain was

formed by volcanicity, what would you look for?

How a block mountain is formed?

The diagram shows how compressional forces cause the formation of a block mountain and a rift valley.

Fault - block mountains

Block Mountains are huge, tilted blocks of rocks that are separated from surrounding rock by faults. A fault is a large crack in rocks a long which there is movement. The diagram above shows, how these mountains are formed. One block was tilted and pushed up. The other block was pushed down. Therefore a block mountain is formed as a result of compressional forces that caused earth movements. The middle block is forced to go up and the sides are forced to go down. The part raised becomes the mountain while the middle part is a valley. Rwenzori mountain is an example of a mountain which was formed as a result of faulting of rocks.

Formation of a rift valley

A rift valley is a long, narrow section of the earth's crust let down between two parallel lines of faults. Valleys are formed as a result of faulting. Faulting is a process through which the earth's rocks break or crack due to forces which are either tensional or compressional. This results into the movement of rocks in different directions. A valley is a low land between hills or mountains. The great rift valley formed as a result of faulting.

Lines of weakness were formed in the earth's rocks. When tensional forces continued to pull, cracks or fault lines were formed. The middle block was forced to sink resulting into a rift valley.

The middle block sinks to form a valley.

How did the lines of weakness develop?

Characteristics of rift valley lakes

They are deep and long. The water cover a long stretch of land. They do not have outlets to the sea which makes the water salty. In Uganda, lakes Albert and Edward are examples of rift valley lakes.

Faulting has some economic values such as:-

Promotes the tourism industry. Many visitors come from different parts of the world to see the rift valley. Watersheds such as lakes are fishing grounds. Some lakes such as Edward and Albert provide fish. Some lakes are used for transport like Lakes Albert and Edward. People use them to cross to different parts of the

Country.

Faulting also has negative effects such as:-

Hinders development of good transport network. It is difficult to construct roads and bridges across the rift valley. Steep sides of the valley experience land slides which destroys crops and animal life. These steep sides are referred to as escarpments. Valley areas are foggy in the morning making it difficult to see clearly. There is always a lot of mist which usually fall in the rift valley areas.

Lakes

A lake is a large accumulation of water level in a depression in the earth's surface or a lake is a large body of water with land on all sides.A depression is a hallow area in the surface of the earth which is a result of land sinking. The process of sinking with water from land is called warping. A depression is filled with water from rainfall or rivers to form lakes.

Examples of lakes in Uganda

L. Victoria, Lake Kyoga, L. George, L. Albert, L. Edward, L. Opeta, L. Kwania, L. Kachira, L. wamala, L. Mburo, L. Nakivali, among others. Lake Victoria and Lake Kyoga are fresh water lakes. They are not found in the rift valley. Lake Victoria is the largest lake in Uganda, East Africa and Africa. Its area is 68,407 square kilometres. It was formed as a result of depression when water accumulated.

Types of lakes

(i) Rift valley lakes.

(ii) Crater lakes.

(iii) Lava dammed lakes.

(iv) Depression lakes.

Depression lakes

These lakes were formed due to the process of warping. The depression formedis filled with water from rivers whose flow was reversed by the tentonic movement of the earth. Lakes such as L. Victoria, L. Kyoga, L. Wamala and L. Kwania are depression lakes. Depression lakes are usually shallow and swampy in nature. Lake Kyoga is the most swampy lake in Uganda.

Why is lake Kyoga the most swampy lake?

Crater lakes

Crater lakes are formed as a result of volcanic eruption. When magma cools it solidifies which leaves a depression on top of a volcano called a crater. When it rains, water collects in the crater forming a crater lake. Examples of crater lakes include: lake Katwe in western Uganda, lake Nyungu and Lake Rutoto in the same region.

Rivers

A river is a large stream of water that flows across the land. A river bank is land along a river. A source of a river is a place where a river begins; a tributary is a stream or a river that empties into a larger river and a distributary is a stream or river that flows out of a larger river. Rivers which flow throughout the year are referred to as permanent rivers like R. Nile and R. Kagera while those which dry up during the dry seasons are called seasonal rivers such as R. Agago and R. Lumansi. Uganda has a number of rivers across the country. Many rivers have their sources in upland or highland areas.

River Nile

This is the longest river in Africa. It covers a distance 6695 kilometres long. River Nile has its source in lake Victoria in Jinja district. It pours its water into the Mediterranean Sea. The river crosses three countries namely south Sudan, Sudan and Egypt. It has waterfalls at different points. A waterfall is a steep drop from a high place to a lower place in a stream or river. 

The waterfalls on the Nile are Owen falls, Bujjagali falls and Kalagala falls. Hydro power stations have been built on these falls such as Nalubale dam, Kiira dam, Bujjagali dam to provide Hydro electricity. Hydro electricity is generated from running water. Other rivers in Uganda are:- Albert Nile, River Kafu, R. Achwa, Katonga river, river Semliki, R. Sezibwa, R. Nkusi, R. Mayanja, R. Mpanga, and Victoria Nile.

Influence of different physical features on climate

We have learnt about the different physical features found in Uganda. These features have different influences on the climate of an area.

 Activity

Activity

1 . What is the appearance or shape of the place where you live?

2. Is the climate warm or cold? Is it wet or dry? What kind of animals live nearby?

3. What do the trees look like?

The influence of mountains

Places located near mountains or highlands experience cool temperatures and receive heavy rainfall especially relief rainfall. Places located near low lands are warmer and receivemoderate rainfall which is mainly convectional. For example, areas near mountains Elgon and Mufumbiro are cooler with relatively high rainfall while places like Pallisa, Kumi and Soroti which are at a low land are warmer with little rain.

The influence of lakes 

Places located near large water bodies such as lake Victoria and Kyoga receive heavy convectional rainfall compared to areas which are located far from water bodies. Places near lake Victoria experience good climate with plenty of rainfall which favour human settlement and crop farming.

The influence of plateaus 

These are flat raised areas. They are relatively cooler. Some of them receive reliable rainfall with low temperatures in some areas. Due to the favourable climate in plateau areas, many human activities are carried out such as crop farming, tourism and cattle rearing.

Influence of physical features on Vegetation 

Mountainous areas receive heavy rainfall and experience cool temperatures. These conditions favour the growth of thick vegetation. The slopes of mountains have fertile soils which support the growth of vegetation.

 Activity

Why do you think it difficult for vegetation to grow on top of

mountains?

Mountain gorillas

Mountain forests grow between 2000-3000m. It is usually a

dense thicket of bamboo. Rainforests grow between 1500-2000m above sea level

Savannah vegetation grows between 500-1000m above sea level. Mountains such as Rwenzori, Mufumbiro, and Elgon have forests. They are suitable habitats for different animal species and birds.

 Animals and birds.

Most animals and birds live in forests, bushes and jungles. However, there are also many animals which live in different physical features, for example crocodiles, fish, hippopotamus, snakes, and tortoises, live in mountains, lakes and rivers. National Parks harbour, several species of mammals such as, Jackals, Hyenas, Impalas, Buffaloes and Zebras.Some Game Parks and Reserves are located in mountainous areas because of the favourable conditions and presence of a variety of wildlife. For example, Bwindi Impenetrable forest and Mgahinga National Parks are famous for Mountain gorillas. Animals found in Mount

Elgon National Park are monkeys, forest hog, bush back, antelope, civet, wild

cat, leopard, jackal, elephant, Buffalo, rock hyrax and many birds such as guinea fowls, sun birds and Turacos. The rift valley has lakes which harbour different animal species and birds. Valleys provide a conducive habitat and good scenery.

The influence of physical features on human beings Lake and rivers Many people in Uganda live near lake shores and riverbanks. Those areas have fertile soils and favourable climate which favour human activities. They easily access water for domestic use and irrigation. There is fishing as the major activity of the people who live there.

The influence of mountains.

Most mountainous areas experience cool temperatures with plenty of rainfall. The conducive conditions attract large numbers of people to settle on the slopes in order to carry out farming activities. The areas around mount Elgon and Mufumbiro ranges have fertile volcanic soils which support farming.

On some mountains, there is wood and honey harvesting. Presence of game parks such as mount Elgon National Park, Mgahinga, Bwindi impenetrable park attracts tourists who create market for the local craft materials made by the people who live nearby.

The influence of the plateau and plains

These are low land areas with plenty of grass suitable for goats, sheep and cattle. The climate is good with moderate temperatures in some areas while others are dry. People grow crops in areas that receive reliable rainfall and rear animals in

drier areas.

Importance of different types of physical features

Mountains and highlands 

Most Mountainous and highland areas have cool climate and reliable rainfall. They have fertile volcanic soils which support crop farming. On the slopes of Mufumbiro mountains, Irish potatoes, bananas, vegetables, fruits and wheat are grown. 

Mountains have a variety of animal species for example mountain gorillas in Mufumbiro ranges. They are tourist attraction sites with beautiful sceneries. Tourism creates employment to people who live near highlands. These areas also influence rainfall formation. In forested areas of mountains, people also practice lumbering. Many forest tree species provide hard wood for timber and furniture.

Plateau 

Plateau areas have plenty of pasture. Most people grow crops and rear cattle and goats. Crops grown include cotton, ground nuts, vegetables, maize, Robusta coffee, beans and bananas. There is also fishing and mining activities.

Lakes and Rivers

Dams are built on waterfalls on rivers to generate Hydro electric power. For example at Karuma falls, there is a dam, on R. Nile, there is Nalubaale, Kiira dam and a new power station was built at Bujjagali falls. Rivers and lakes are the main fishing grounds especially on lake Victoria, Kyoga, Albert, George, among others. They provide fish which is a source of proteins. Lakes and rivers are sources of water for home and industrial use. Some industries in Uganda such as Nile breweries at Jinja and Uganda breweries at Luzira use water from Lake Victoria to cool their machines and to process the raw materials.

Lake Victoria 
They are used to facilitate transport for both goods and people across the water bodies. Attract tourists who provide foreign income. Both local and international tourists visit major water bodies in Uganda. Lakes and rivers provide water which peopleuse to water crops especially during the dry season. People use water for recreational activities such as boat races and rafting. Recreation is what people do during their free time to relax and for leisure.