Savannah ecosystem, why biodiversity in the savannah is under threat, how people use the savannah, Lake Chad.

Question 1

1. Where is the Savannah grassland ecosystem found?

Answer 1

Within the tropics 5-15° north and south of the equator, between tropical forests and hot deserts.

Question 2

2. What is the Savannah grassland ecosystem also known as?

Answer 2

Semi-arid grassland.

Question 3

3. Does the wet season in the savannah occur in the summer or winter?

Answer 3

Summer.

Question 4

4. The rainfall in the savannah is concentrated for how many months of the year?

Answer 4

5-6 months.

Question 5

5. Xerophytes are plants that…

Answer 5

Can survive drought.

Question 6

6. Pyrophytes are plants that…

Answer 6

Adapted to tolerate fire.

Question 7

7. How has the Acacia tree adapted to live in the savannah?

Answer 7

• Broad flat canopy reduces water loss.
• Thorns on branches to stop animals from eating them.
• Large roots to get water from deep underground.
• Small leaves with waxy skins to reduce the amount of water lost through transpiration.

Question 8

8. Why is the savannah a popular tourist destination?

Answer 8

Safari:

• Animals.
• Plants.
• Insects.

Question 9

9. Why are there less stores of nutrients in the savannah than in the rainforest?

Answer 9

Shorter growing seasons and fires return carbon into the atmosphere.

Question 10

10. Due to the high temperatures what happens to the organic matter?

Answer 10

Decays rapidly.

Question 11

11. What is fire important to maintain the savannah ecosystem?

Answer 11

• It maintains the grass community and mineralises the litter layer.
• kills weeds.
• prevents trees from growing.

Question 12

12. What are the most important nutrient recyclers?

Answer 12

Termites.

Question 13

13. Episodes of drought in the Savannah last for ____ months of the year.

Answer 13

4-8 months.

Episodes of drought in the Savannah last for 𝟒-𝟖 months of the year.

Question 14

14. Why is the savannah significant in the global carbon cycle?

Answer 14

They cover 20% of earth’s land surface so despite having significantly fewer trees than rainforests or temperate forests they are significant in the carbon cycle.
Regular bushfires release many tonnes of CO₂ into the atmosphere.

Question 15

15. Give an example of a producer in the savannah ecosystem.

Answer 15

• Grasses.

- Acacia Tree.

Question 16

16. Give an example of a primary consumer in the savannah ecosystem.

Answer 16

• Baboon.
• Rhino.
• Giraffe.
• Zebra.

Question 17

17. Give an example of a Secondary consumer in the savannah ecosystem.

Answer 17

• Cheetah.

- Hyena.

Question 18

18. Give an example of a tertiary consumer in the savannah ecosystem.

Answer 18

• Lion.

Question 19

19. What is the greatest threat to the animals in the savannah ecosystem?

Answer 19

Poaching.

Question 20

20. What animal poaching example of this did we study?

Answer 20

Rhino for their horns.

Question 21

21. Give 3 potential solutions to reduce rhino poaching?

Answer 21

• De-horn the Rhino.
• Poison the horn with dye.
• Manufacture synthetic Rhino horn.
• Make use of drones.
• Fix GPS and Camera in Rhino Horns.

Question 22

22. What is desertification?

Answer 22

The spread of the desert, or desert conditions.

Question 23

23. What are the three main reasons for desertification?

Answer 23

• Slash and burn of the savanna trees and bushes to make space for farming reduces evapotranspiration and so eventually leads to a reduction of water.
• The removal of vegetation means that leaf litter can no longer fall into the soil, therefore, the nutrient cycle is broken and the shrubs no longer replace nutrients.
• The destruction of the tree canopy exposes the soil to rain splash erosion.
• On steeper slopes, the power of the water carries material which then erodes downwards this is called gulley erosion.

Question 24

24. What two types of farming take place in the African savannah?

Answer 24

• Arable Farming (crop).

- Pastoral Farming (animals).

Question 25

25. What is a fallow period?

Answer 25

When fields are left to regain its nutrients.

Question 26

26. What has happened to Lake Chad?

Answer 26

Significantly reduced in size.

Question 27

27. Why has this happened to Lake Chad?

Answer 27

• Deforestation in the lakes drainage basin causing a drier climate.
• The over-abstraction of water from the rivers both for domestic supply (in cities) as well as intensive farming and irrigation.
• 20 dams have been built in northern Nigeria.

Question 28

28. What have been the impacts of Lake Chad on people and the environment?

Answer 28

• Cholera and Polio as people relying on the lake for their water.
• Salinisation of soil.
• Wetland ecosystem has dried out so birds and fish populations have declined.
• Migration to cities such as Kano.

Question 29

29. Give 2 ways that the transaqua project could save Lake Chad.

Answer 29

• Transfer water from the Democratic Republic of Congo via a canal between the River Congo and River Chari.
• Generate Hydroelectric Power which would create opportunities for people and tackle poverty.