Living worlds

Question 1

Describe how the nutrient cycle works.

Answer 1

1. When dead material decomposes, nutrients are released into the soil.
2. Then the nutrients are taken up by the plants. The the plants are eaten by consumers.
   3.When the plants or consumers die, nutrients return to soil
3. Process continues in a cycle. The transfer of nutrients is called nutrient cycling.

Question 2

Describe the pond bottom and what live there?

Answer 2

Little light and oxygen E.g. decomposers (bacteria)

Question 3

Which animals live there in mid water?

Answer 3

Most fish (predators) here

Question 4

Describe the pond surface and which animals live there?

Answer 4

Lots of light and oxygen
E.g. Ducks, tadpoles

Question 5

Describe the pond margin and which animals live there?

Answer 5

Sheltered habitats for animals
E.g. Frogs

Question 6

Which animals live above the pond surface?

Answer 6

E.g Kingfishers (type of bird), Dragonflies

Question 7

What is Eutrophication?

Answer 7

The process in which water or parts of it become overly enriched with minerals or nutrients.

Question 8

Causes of Eutrophication?

Answer 8

-Runoff and erosion ( from poor land use)
-Nitrogen compounds produced by cars and factories

Question 9

When warm air rises it creates low or high pressure?

Answer 9

Low pressure

Question 10

When cool air sinks it creates low or high pressure?

Answer 10

High pressure

Question 11

1.Climate of the Tropical Rainforest

2.Why is it so hot?

3.Why is it so wet?

Answer 11

1. Hot and wet humid throughout year.
2. The suns rays shine directly onto earths surface at the equator
3. The hot, wet air rises, cools and condenses causing convectional rainfall

Question 12

What is the soil like in the rainforest and why?

Answer 12

Poor soil as no nutrients below taken up by vegetation.

Question 13

Animal adaptations in the rainforest.

Answer 13

Sloth: (Found in main canopy)
-Long claws/ arms to help climb trees

Toucan: (Found in main canopy)
- Bright bill to attract mates

Poison dart frog: (Found on the forest floor)
-Poisonous skin so if predator tries to eat it, they will get poisoned

Question 14

Plant adaptations in the rainforest

Answer 14

Drip tip: (Found on forest floor)
- Leaves with pointed tip to channel the water straight to the roots and so the weight of water doesn’t damage leaves

Lianas: (Found in under canopy)
-Grows up trees to get sunlight and get taller

Buttress roots: ( Found on the forest floor)
-Wide base to grow tall and take up nutrients.

Question 15

Causes of deforestation, what % and how each cause deforestation.

Answer 15

80% Cattle ranching- More demand for fast food
10% Commercial agriculture- Crops such as pineapple, oil are grown
5%- Small scale agriculture- Cutting or burning areas of the rainforest for small farms
3%- Logging-Cutting down trees to sell wood
2%- Urbanisation- People run out of places to live so have to cut down the rainforest to build houses

Question 16

Impacts of deforestation.

(Positives (only economic) and negatives)

Answer 16

Positives:
Economic- Lots of money made from selling wood.

Negatives:
Economic- In the long term, can destroy recourses of that country

Environmental- Animals loose their habitat

Social- Native tribes have been forced to move

Question 17

Why the rainforest is important?

Answer 17

80% of food comes from there

25% medicines

Question 18

Sustainable strategies (6 or 9 mark question).

What is the strategy?
Explain?
Advs and Disadvs?
Local, National or International?

Answer 18

Selective logging- (National) Ensure the rainforest canopy is preserved- trees grow until fully grown so younger trees can mature
Adv: Protects ground from erosion.
Disadv: Removes habitat

Ecotourism (Local)- Volunteers help out in the rainforest- preserve the rainforest
Adv: Visitors help the environment
Disadv: To some extent some areas could be ruined by people being there

Education (International)- A protected area so no one can cut down the rainforest- People know how to treat the rainforest
Adv: Can lead to rainforest being protected
Disadv: Some people may break rules and go in

Question 19

1. Why are deserts dry?
2. Why are they so hot?

Answer 19

1. They are high pressure and the equator has lost moisturiser
2. The suns rays are more concentrated

Question 20

Plant adaptations in the desert?

Answer 20

Ephemerals- Bright flowers to attract pollinators
Acacia tree- Thorns to stop animals eating the leaves
Saguaro cactus- Spikes protect cacti from animals wanting to use its stored water

Question 21

Animal adaptations in the desert?

Answer 21

Long- eared jerboa- Large ears to loose heat and live underground to keep cool
Camel- 3 eyelids and long eyelashes to protect eyes from sandstorm
Thorny devil- False head hides real head from predators

Question 22

Opportunities in the Thar desert

Answer 22

Mining-gypsum and feldspar used in medical industry
Tourism- desert safaris on camels
Subsistence farming- Small scale, for family

Question 23

Name of rainforest case study and where is it located

Answer 23

Amazon rainforest. In south America

Question 24

Name of desert case study and where its located

Answer 24

Thar desert. Between India and Pakistan

Question 25

Challenges in the Thar desert

Answer 25

Extreme temperatures- Can exceed to 50 degrees. Barely any water and houses will get warm
Water supply- Only 120-140mm a year- Farms need water for crops and to feed animals.
Inaccessibility- Cant get to the desert as sand in the way

Question 26

What is desertification?

Answer 26

Process of land turning into desert the quality of soil declines overtime.

Question 27

Things that cause desertification

Answer 27

Overgrazing due to farmers becoming less nomadic (moving around less)- farmers rely on water and land so don’t regularly move to new fertilized areas.
Soil erosion- Overuse of land remove nutrients from the soil
Deforestaion- Soil is exposed to rain so nutrients get washed away, leaving soil infertile

Question 28

Strategies to reduce the risk of desertification

What is the strategy?
Explain?
Advs and Disadvs?

Answer 28

Afforestation- Planting more trees so soil improves
Adv: Dead leaves add more nutrient to the soil
Disadv: Expensive and takes a long time for trees to grow

Bunds- Small stone walls built along a slope to trap water
Adv: Improves quality of soil
Disadv: Not much rainfall

Energy efficient stoves- Using appropriate technology
Adv: People arent cutting down as much fuel wood
Disadv: Still use wood, just less