Vegetation - Class 7 Social Studies Revision Notes

• Vegetation Zones in Africa
• Factors Influencing Distribution of Vegetation
• Characteritics of Vegetation in Different Zones
  • Tropical Rainforests
  • Savannah Vegetation
  • Mediterranean Vegetation
  • Desert and Semi-desert Vegetation
  • Temperate Grassland Vegetation
  • Mangrove Vegetation
  • Mountain Vegetation

Vegetation refers to the total plant life/cover on the earth sorface.
It consists of trees, bushes, thickets and grasses.
We have natural vegetation and planted vegetation.

Natural vegetation
This is a type of vegetation that grows on its own

Planted vegetation
Also called man-made or artificial vegetation
This is a type of vegetation cultivated by human beings.

Vegetation Zones in Africa

1. Tropical rainforest
2. Savannah vegetation
3. Mediterranean vegetation
4. Temperate grassland vegetation
5. Mountain vegetation
6. Desert and semi desert vegetation
7. Mangrove vegetation

Factors Influencing Distribution of Vegetation

1. Climate
2. Altitude an relief
3. Soils
4. Human activities
5. Government policy
6. Animal activities

Characteritics of Vegetation in Different Zones

Tropical Rainforests

It is also called equatorial vegetation
Is located latitude 5°N and 5°S of equator.
Are found in equatorial climatic zone.
Are found in:

• Eastern madagascar
• Gabo
• Congo
• Ghana
• Cote d ivoire
• Cameroon
• Nigeria
• Benin
• Togo

Characteristics

1. Tall evergreen trees
2. Tops of trees form layers called canopies
3. Trees have straight trunks
4. Trees have buttress roots
5. Trees have broad leaves
6. The forest has little or no undergrowth
7. Has climbing plants such as lianas
8. Consists of different tree species
9. Trees are mainly hardwood e.g.
   
   • Oak
   • Ebony
   • Obeche
   • Rosewood
   • Sapele
   • Camphor
   • Teak
   • Mahogany
   • Iroko
   • Ironwood
   • Mvule
   • Heartwood.

Savannah Vegetation

It covers the largest portion of africa
Is found between 5°N and 15°S of equator
Grows in tropical type of climate
It is made up of; savannah woodland and savannah grassland

Savannah Woodland

1. Main vegetation are trees
2. Trees are of medium height
3. Trees have umblerra shape at the top
4. Trees are widely spaced
5. Trees are decidious
6. Tall grass grow between the trees
7. Trees have thick barks and deep roots
8. Main trees are acacia and baobao

Savannah Grassland

1. Main vegetation is grass
2. Is made up of grass and trees
3. Trees are few and scattered
4. Grasses are tall and have stiff blades
5. Main trees are acacia and baobao
6. Trees have small leaves and thorns
7. Trees have dep roots and thick barks
   Examples of savannah woodland in africa
   • Miombo woodland in tanzania
   • Shimba hills forest of kenya
   • Zambia
   • Malawi
   • Angola

Mediterranean Vegetation

Also called marguis vegetation
Grows in the mediterranean climatic zone

Characteristics

1. Is made up of woodland(trees)and shrubs
2. Trees are short and thin
3. Main trees are oak, olive, fir, cedar, beech, pine, cypress, parasal.
4. Trees are short and cone shaped
5. Trees have small hard evergreen leaves
6. Trees have deep taproots and thick stems
7. Aromatic shrubs such as thyme, lavender, rosemary, aloe, sage.
8. Other plants have fleshy stems and shiny leaves.

Desert and Semi-desert Vegetation

Found in areas experincing arid and semi-arid climate
Found in sahara and namib desert, kalahari and sahel regions
Consists mainly of drought resisitance shrub

Characteristics

1. Mainly includes fleshy and thorny plants e.g.cactus and euphorbia
2. Plants are deep rooted
3. Plants have thin, spiky needle shaped leaves
4. Scattered thorny bushes and tough bunch of grass
5. Plants store water in fleshy stems and leaves
6. In some places the ground is bare

Temperate Grassland Vegetation

Grows in warm temperate climatic zone
Is also called the veld
Main vegetation is grass

Characteristics

1. Tuft/short grass and shrubs
2. Grass turns yellow-brown during the dry season
3. Has shrubs,bulbons plants and few trees.
4. Few trees are found along the river valleys.

Mangrove Vegetation

Is found along the muddy coasts of eastern and western africa.

Characteristics

1. Trees grows in salty water
2. Trees are hardwood and of medium height.
3. Trees are evergreed and they grow close together
4. Trees have aerial/breathing roots above the water surface.

Mountain Vegetation

Is found in the highlands and mountain regions
It grows in belts or zones according to the altitudes
It changes with increase in altitude
It is also known as afro-alpine vegetation
At average altitude above 400m there is no vegetation.
It grows on the slopes of :

1. Nyandarua ranges
2. Cameroon highlands
3. Ethiopia highlands
4. Atlas mountains
5. Mt.kilimanjaro
6. Mt.kenya