Tropical Rain Forests - Biomes

Question 1

Climate

Answer 1

Hot and wet all year

Question 2

Temperature

Answer 2

20-28 degrees C

Sun overhead all year round

Question 3

Rainfall

Answer 3

• High all year round
• 2000mm per year
• Rains every day
• Usually in afternoon (high temps create convectional rainfall)

Question 4

Convectional Rainfall

Answer 4

• Sun warms ground.
• This conducts heat to air above and evaporates surface water.
• Warm air can hold lots of water vapour.
• Warm wet air rises.
• As rises, it cools.
• Cool air can hold less water vapour.
• Water condenses to form clouds and rains.

Question 5

Soil Moisture Budget

Answer 5

• The balance between water inputs and outputs in the soil.
• High because precipitation is higher than potential evaporation.

Question 6

Rainforest Soils

Answer 6

Latosols

Very nutrient poor because:
- Leaf litter & organic matter broken down so quickly (warm & wet climate)
- Growing season continues all year – as soon as dead organic matter broken down, nutrients re-absorbed by plants. Few nutrients remain in soil.
- Nutrients leached down the soil column by heavy rainfall.

Question 7

Plant adaptations - Emergent

Answer 7

• 40m
• Tallest trees.
• Poke out of main canopy layer.
• Straight trunks
• Branches and leaves only at top (where they can get light)
• Buttress roots to support trunks

Question 8

Plant adaptations - Main canopy

Answer 8

• 30m
• Continuous layer of trees
• Only have leaves at top
• Dense layer of leaves shades rest of forest

Question 9

Plant adaptations - Undercanopy

Answer 9

• 20m
• Younger trees (yet to reach their full height)
• Only survive in breaks in canopy where light can get through

Question 10

Plant adaptations - Shrub Layer

Answer 10

• 10m
• Quite dark
• Shrubs have large, broad leaves to absorb as much light as possible

Question 11

Plant adaptations - Leaves

Answer 11

• Waxy leaves – helps repel rain
• Drip tips – channel water to run off

Means:
- Weight of water doesn’t damage plant.
- No standing water for fungi & bacteria to grow / leaf to rot.

Question 12

Plant adaptations - Lianas

Answer 12

Root in soil & clime up trees searching for light

Question 13

Plant adaptations - Epiphytes

Answer 13

• Grow on trees
• E.g. orchids and bromeliads
• Help plants reach light

Question 14

Animal adaptations - Canopy

Answer 14

• Live in canopy
• Plenty of food
• E.g. flying squirrels (flaps of skin for gliding between trees)

Question 15

Animal adaptations - Nocturnal

Answer 15

• Jaguars, sloths, vampire bats
• Save energy by sleeping in hot day.
• Feed at night when cooler

Question 16

Animal adaptations - Low light

Answer 16

• Underneath canopy
• E.g. Tapirs and anteaters
• Excellent sense of smell and hearing to detect predators

Question 17

Animal adaptations - Swimming

Answer 17

• Many TRF animals can swim
• Allows them to cross river channels and cope with forest floor flooding

Question 18

Deforestation

Answer 18

• Small Scale Farming
• Cattle Farming
• Commercial Agriculture
• Commercial Logging
• Other

Question 19

Deforestation - Small Scale Farming

Answer 19

• Trees cleared to set up small subsistence farms.
• Often slash & burn
• Vegetation cut down, left to dry, then burnt.

Question 20

Deforestation - Cattle Farming

Answer 20

Forest cleared to make room for cattle grazing

Question 21

Deforestation - Commercial Agriculture

Answer 21

Trees felled for planting crops.

Soya and palm oil

Question 22

Deforestation - Commercial Logging

Answer 22

• Wood used for timber, pulp, paper.
• Road building for logging also makes new areas accessible for agriculture

Question 23

Deforestation - Other

Answer 23

• Mineral extraction (gold & iron ore)
• New settlements
• Building dams for hydroelectric power floods large areas of forest

Question 24

Deforestation - Environmental Impacts

Answer 24

• Habitat loss –> reduced biodiversity
• Decreased interception so more water in soil –> reduces soil fertility & flooding more likely.
• Evapotranspiration rates decreased –> less water vapour in atmosphere, less rain falls.
• Global warming –> fewer trees = EGE.

Question 25

Deforestation - Social Impacts

Answer 25

- More jobs = improved quality of life for locals. - Traditional livelihoods destroyed if plants and animals lost. - Native tribes forced to move if their land cleared. - Locals at risk as not immune to western diseases brought by newcomers. - Conflict between natives, landowners, mining companies, and logging companies over use of land.

Question 26

Deforestation - Economic Impacts

Answer 26

- Logging, farming and mining create jobs. - Lots of money made from selling timber, mining and commercial farming. - Long term, it will destroy resources that countries depend on (timber).

Question 27

Development Issues - Population Change

Answer 27

- Pop growing - Indigenous inhabitants decreasing. - More people need more resources and space. - Many more small scale subsistence farmers now --> people with no/unproductive land opening up more areas.

Question 28

Development Issues - Economic Development

Answer 28

- Commercial activities brought huge economic development to countries with TRFs (mining, logging, etc). - Investments in infrastructure --> new roads opening up inaccessible forest - Countries develop economically = people have more money = use more resources = more deforestation.

Question 29

Agriculture extension and intensification

Answer 29

- Increase in forest clearance for cash crops. - Monocultural plantations. - Meat consumption increasing --> more room for cattle needed. - 80% deforested land in Brazil for cattle. - S&B sustainable if left to recover (but doesn't happen due to pop pressure).

Question 30

Implications on Biodiversity

Answer 30

TRF = biome with highest biodiversity. Humans causing decline. Habitat loss - Deforestation destroys habitats. - Natural veg replaced with land uses with lower biodiversity (monoculture farming). Fragmentation - Sections felled for other land use. - Split up into isolated fragments. - Lower biodiversity in fragments than in continuous forest. - Populations cup off from eachother so can't come together to reproduce. - Animals leaving fragment may end up dead.

Question 31

Implications or Sustainability

Answer 31

1. Selective logging, replanting, and creation of national parks. 2. Eco-tourism --> nature based and doesn't harm environment, benefits locals. - Locals employed so don't log/farm. - Raises awareness of conservation issues. 3. TRF in less developed countries --> borrow money from organisations which leads to industrial activities being allowed to repay debts. - Debt for nature swaps alternative solution --> when part of a countries debt paid off by someone else in exchange for investment in conservation.