Topic 8 - Forests Under Threat Flashcards
Where are Tropical Rainforests located?
Around the equator
Low pressure - rises - ccc - rain
But also hot due to the the sun straight overhead
Tropical rainforest structure
Shrub layer - forest floor - few plants Under canopy - densest layer Canopy - tree reaches 35m - uneven Emergents - individual trees - 50m high
Plant adaptations
Drip tip leaves:
Thick, waxy leaves with drip tips
Shed water quickly to prevent leaves rotting
Butteress roots: Tall slender trunks No branches Triangular roots Support enormous weight of the trees
Animal adaptations:
Sloths:
Huge claws to hang from branches
Camouflage
Fur grows away from feet to help shield rain
Big cats:
Camouflaged fur
Dark and light fur patches blend with shade and sunlight on the floor
Nutrient cycle has 3 stores
Soil
Litter
Biomass
Rapid because of the hot, damp weather
Two ways nutrients can enter the soil
Decomposition
Rock weathering
Which are the two smaller stores and why
Litter and soil
Because they have 2 ways the nutrients can be lost
Consumer
Something that eats something
Producer
Plants
Herbivores
Plant eaters
Carnivores
Meat eaters
Decomposer
Dead things
Tropical rainforests have complex web systems - why?
Because most animals are quite selective about what they eat
Deforestation
The deliberate cutting down of forests to exploit forest resources
Forest lost causes
Direct threats
Poverty, resource demand, debt, economic development
Mineral exploitation’s, HEP, biofuels
Forest lost causes
Indirect threats
Climate change causing temperatures to rise
Climate change causing climate stress (extreme droughts)
Why we should manage the rainforest
Manage CO2 levels
Cash crops
To get medicine ingredients
Climate stress
How to preserve the tropical rainforest
Forest regeneration - preserve older trees
Scientists - monitor areas
Ecotourism - know all materials are local
Shifting cultivation - slash and burn
Selective Logging
CITES
The convention on international trade in endangered species is an international treaty
Positives: many countries have signed up
Wide variety of protected species
Negatives: species have to be under threat to get ‘on the list’
Protects species not ecosystems- does not prevent deforestation
REDD
Purpose is to stop deforestation
Positives: sustainable management of forests
Negatives: offsetting is an easy way for developed countries to appear to reduce their CO2 pollution, without actually reducing it
Local scale sustainability of rainforests
Costa Rica
Small scale farming and forestry
Positives: tourist attraction - income
Negatives: only small scale
Taiga biome
North of the Tropic of Cancer Climate is cool and dry Short summers = 10° Long winters = -20° Snow Few animals Evergreen coniferous trees
Animal and plant adaptations in the taiga biome
Coniferous forest
Cone shaped - helps shed winter snow
Needles - prevented by a waxy coating which prevents damage by frost and limits water loss during dry periods
Tree roots are shallow - to avoid the frozen ground below
Branches - flexible and bend downwards to shed winter snow and not break
Yellow rumpled warbler
During winter - disperse in loose flocks
Sing from the high canopy of trees
Arctic ground squirrel
Huddled in an underground burrow for 7 to 8 months
Body temperature drops and all metabolic functions slow way down
Difference between the nutrient stores in the taiga and rainforest biome
Taiga Rainforest
•slow nutrient cycle •fast nutrient cycle
•big litter store •small litter store
•small biomes •large biomes
Wildfire
Uncontrolled burning through a forest, gras,lands or scrub
Thick carpet of pine needles is perfect to help start a fire
Summer storms generate lightening strikes
Coniferous trees contains sticky resin, which burns easily
Positives of fire: allows forest to regenerate
Negatives of fire: fire tolerant species begin to dominate reducing biodiversity
Pests
A plant, animal or disease introduced from one area to another which causes ecosystem damage
Negatives: reduce commercial value of the forest
Change the landscape from more dense trees to fewer trees
Example: white pine blister rust
A fungal disease that attacks white pine trees
Acid rain
Negatives: makes lakes and wetlands so acidic gah Trisha and aquatic planets die
Damages needles and their ability to photosynthesise
Damaged souls contain less calcium and magnesium (these are essential plant nutrients)
Future for fires, pests and acid rain
Fires - global warming will mean drier and warmer conditions and therefore the frequency of fires will increase
Pests - warming by climate change is making it easier for pests and disease to attack
Acid rain - more fossil fuels = more burning = more acid rain
Conserving taiga biomes
For
Environmentalist, many indigenous groups, many scientists
- taiga is one of the last untouched biomes
- the forests are vital global carbon sinks to help combat global warming
- culturally important
- exploitation causes deforestation, degradation and pollution
Conserving taiga biomes
Against
Businesses, government, local and some residents
- Brings jobs and income
- resources can be exported, boosting national GDP
- exploitation affects only a tiny fraction of the vast biome
- some exploitation is renewable e.g. HEP
RAMSAR sites and work heritage sites
Give areas of global importance to give them an extra level of protection
However protecting them from threats of global warming and illegal deforestation, mining and hunting is difficult
National parks
These areas prevent commercial development of the taiga within their boundaries
Aim to preserve the taiga ecosystems and biodiversity
Often parks and protected wilderness areas are not big enough
Sustainable forestry
Trees that are cut down are replanted with native taiga species
The whole forest is carefully managed so that biodiversity is not damaged
Allow the migration of animals
Very expensive
Only for large companies
Long term planning
Selective logging
Only removes large, vulnerable trees and leaves some of the forest intact
