Savannah ecosystem, why biodiversity in the savannah is under threat, how people use the savannah, Lake Chad. Flashcards
1
Q
- Where is the Savannah grassland ecosystem found?
A
Within the tropics 5-15° north and south of the equator, between tropical forests and hot deserts.
2
Q
- What is the Savannah grassland ecosystem also known as?
A
Semi-arid grassland.
3
Q
- Does the wet season in the savannah occur in the summer or winter?
A
Summer.
4
Q
- The rainfall in the savannah is concentrated for how many months of the year?
A
5-6 months.
5
Q
- Xerophytes are plants that…
A
Can survive drought.
6
Q
- Pyrophytes are plants that…
A
Adapted to tolerate fire.
7
Q
- How has the Acacia tree adapted to live in the savannah?
A
- 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.
8
Q
- Why is the savannah a popular tourist destination?
A
Safari:
- Animals.
- Plants.
- Insects.
9
Q
- Why are there less stores of nutrients in the savannah than in the rainforest?
A
Shorter growing seasons and fires return carbon into the atmosphere.
10
Q
- Due to the high temperatures what happens to the organic matter?
A
Decays rapidly.
11
Q
- What is fire important to maintain the savannah ecosystem?
A
- It maintains the grass community and mineralises the litter layer.
- kills weeds.
- prevents trees from growing.
12
Q
- What are the most important nutrient recyclers?
A
Termites.
13
Q
- Episodes of drought in the Savannah last for ____ months of the year.
A
4-8 months.
Episodes of drought in the Savannah last for 𝟒-𝟖 months of the year.
14
Q
- Why is the savannah significant in the global carbon cycle?
A
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.
15
Q
- Give an example of a producer in the savannah ecosystem.
A
- Grasses.
- Acacia Tree.
16
Q
- Give an example of a primary consumer in the savannah ecosystem.
A
- Baboon.
- Rhino.
- Giraffe.
- Zebra.
17
Q
- Give an example of a Secondary consumer in the savannah ecosystem.
A
- Cheetah.
- Hyena.
18
Q
- Give an example of a tertiary consumer in the savannah ecosystem.
A
- Lion.
19
Q
- What is the greatest threat to the animals in the savannah ecosystem?
A
Poaching.
20
Q
- What animal poaching example of this did we study?
A
Rhino for their horns.
21
Q
- Give 3 potential solutions to reduce rhino poaching?
A
- De-horn the Rhino.
- Poison the horn with dye.
- Manufacture synthetic Rhino horn.
- Make use of drones.
- Fix GPS and Camera in Rhino Horns.
22
Q
- What is desertification?
A
The spread of the desert, or desert conditions.
23
Q
- What are the three main reasons for desertification?
A
- 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.
24
Q
- What two types of farming take place in the African savannah?
A
- Arable Farming (crop).
- Pastoral Farming (animals).
25
Q
- What is a fallow period?
A
When fields are left to regain its nutrients.
26
Q
- What has happened to Lake Chad?
A
Significantly reduced in size.
27
Q
- Why has this happened to Lake Chad?
A
- 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.
28
Q
- What have been the impacts of Lake Chad on people and the environment?
A
- 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.
29
Q
- Give 2 ways that the transaqua project could save Lake Chad.
A
- 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.
