the savanna biome

Question 1

where is the savanna grassland located

Answer 1

between the tropics of cancer and capricorn
5* - 20* N/S of the equator

Question 2

what are the distinct features of the savanna

Answer 2

-large patches of grassland
-usually found in brazil, africa, australia and india
-periods of drought
-wildfires are common
-mix of tropical forest and desert
-trees, occasional shrubs
- 22-28 degrees celcius
- 20-50 inches of rainfall (1000mm per year)
-rainfall is concentrated in 6-8 months
-fires may occur during drought

Question 3

what do the fires that occur during a drought result in?

Answer 3

the fires kill enough trees to prevent it becoming a forest

Question 4

describe the environment during the wet season

Answer 4

leaves on trees
green elephant grass(3-4m tall)

Question 5

describe the environment during the dry season

Answer 5

no leaves
yellow grass which dies leaving it vulnerable to erosion

Question 6

properties of the baobab tree

Answer 6

-stores water
-thick bark
-grows over 30m in height and 7m in diameter
- shallow roots
- fire resistant
-fewer leaves
- large barell-like trunk

Question 7

what do the shallow roots on a baobab tree mean

Answer 7

it can collect water as soon as it rains

Question 8

what do the fewer leaves on a baobab tree result in

Answer 8

reduces the water lost by transpiration (water droplets not being able to reach the ground as being blocked by the leaves)

Question 9

how much water does the large barell-like trunk of a baobab tree store

Answer 9

up to 500litres of water

Question 10

properties of the acacia tree

Answer 10

• wide
• leaves are high up
• provides shade for animals
• grows up to 20m in height
  -2m in diameter
  -small leaves with waxy skin
  -thorns on branches
• long tap roots

Question 11

how big does the baoban tree grow

Answer 11

over 30m in height abd 7m in diameter

Question 12

what is good about the leaves being high up on the acacia tree

Answer 12

cant be eaten by animals

Question 13

how big does the acacia tree grow

Answer 13

up to 20m in height and 2m in diameter

Question 14

what do the small, waxy leaves on the acacia tree reduce

Answer 14

it reduces the amount of water lost through transpiration

Question 15

what do the thorns on an acacia tree’s branches do

Answer 15

deter animals from eating then

Question 16

whats a benefit of the acacia trees long tap roots

Answer 16

during the dry season the roots are able to reach water stores underground, keeping the tree alive for longer

Question 17

what is the soil in the savanna like

Answer 17

-porous, drains rapidly
- thin humus layer
- not many plants to provide nutrients
- high rates of decomposition in the wet season
- humus-decomposed leaf litter has lots of nutrients

Question 18

what is desertification

Answer 18

degregation of land and vegetation, soil erosion and loss of top soil + fertile land
(turning into a desert)

Question 19

facts about desertification

Answer 19

every country is affected by soil degration (desertification)

can take 500yrs to create 2.5cm of soil but only a few years to destroy it, caused by human factors

Question 20

how can farming damage soils

Answer 20

soil is vulnerable, chemical fertilasation weaken the living organisms responsible for
soil fertility. regular plowing dries out and comacts the soil

Question 21

how much land is lost through desertification

Answer 21

12 million hecter, a third of land threatened and 10 countries affected

Question 22

what is the impact of desertification

Answer 22

soil exhaustion reduces food production
20 million tonnes of grain lost through desertification

Question 23

sustainable solutions of desertification

Answer 23

-planting trees to slow down wind erosion
- the great green wall in africa
-vegitation fences to anchor the soil
- farming without plowing

Question 24

what is agroecology

Answer 24

sustainable farming that works with nature

Question 25

is desertification a human or natural process

Answer 25

human

Question 26

how does plowing lead to desertification

Answer 26

compacts and dries up soil

Question 27

how does monoculture lead to desertification

Answer 27

plants will take all of a certain nutrients

Question 28

how does taking too much ground water lead to desertifcation

Answer 28

leaves little water for vegitation

Question 29

how does overgrazing lead to desertification

Answer 29

theres no crops or vegitation if farm animals eat them

Question 30

how does using fire lead to desertification

Answer 30

releases co2 and destroys vegitation

Question 31

how does poor irrigation lead to desertification

Answer 31

bad water, too much salt and chemicals

Question 32

how does over cropping lead to desertification

Answer 32

not enough nutrients for all the plants

Question 33

what does the great green wall in africa achieve

Answer 33

provides micro nutrients for the soil
provides an income

Question 34

what is happening to lake chad

Answer 34

is disapearing due to climate change
- poor irrigation methods removing too much water
-intense farming

Question 35

how can the tranaqua project help lake chad

Answer 35

could transfer 50 billion m^3 of water a year to lake chad through a series of dams
- generate up to 15-25 billion kwh of hydro electricity