Rainforests Flashcards
(24 cards)
What is a biome?
An ecosystem on a continental scale
What pattern does biomes follow?
-Lines of lattitude on the earth because of the amount of solar radiation each point receives
What kind of biomes are found at a higher lattitude?
- Cooler and drier
Why is it hotter and wetter near the equator?
-Air warmed by the sun rises at the intercontinental convergence zone and forms cumulonimbus clouds due to the moisture it carries
What is the climate of a Tropical Rainforest?
- Hot and humid
- Very minimal variation in temperature
- No seasons
Where are tropical rainforests found?
- Between the Tropic of Cancer and the Tropic of Capricorn
What is an ecosystem?
- A community of plants and animals living together in a habitat
- The lives of the plants and animals are interdependent on eachother
What is an abiotic factor?
- Something non living
- Such as sunlight, water pH, temperature etc
What is a biotic factor?
- A factor caused by something living
- Omnivores, herbivores etc
What are the layers of a rainforest?
- Forest floor
- Under-storey
- Canopy
- Emergent layer
What are the features of the forest floor?
- Very dark due to thick canopy
- Lots of plant life due to sun further up as well as shrubs but minimal leaves
- Lot of small organisms and detritivores
- Buttress roots and Amphibians
What are the features of the under-storey?
- Light is let in when a tree dies but mostly dark
- Fastgrowing leafless and straight trunks
- Minimal animals due to them mostly being in canopy
- Macaranga plants
What are the features of the canopy?
- Light as is close to the tree tops
- Dense with life with lots of leaves to catch as much sun as possible
- Tamarins, fig trees, spider monkeys etc
What are the features of the emergent layer?
- Very light as is in the free area with visible sky
- Tallest trees gathering all the light with lots of branches
- Less animals because it is really high up
- Kapoc trees, Epiphytes and small mammals such as monkeys
Where is the South East Asian rainforest and how large is it?
- On the islands between mainland Asia and Australia
- It covers twice the size of Alaska
- made of 20,000 tiny islands
Why is the temperature so humid in the SEA rainforest?
- it is completely surrounded by ocean making it an incredibly constant temperature
How old is the SEA rainforest?
- 100 million years old
What is the concentraion of animals/plants that are native and how are they adapted in the SEA rainforest?
- 20 % of the worlds animal and plant species
- Contains three of the most diverse countries for biodiversity
- 4 of 25 biodiversity hotspots
- Dipterocarp trees are the main tree which are heavily relied on by epiphytes such as strangler figs
How is the SEAR used economically?
- Commercial wood and logging trade
- Medicinal purposes
- 6.7 billion to be made in cancer drugs
- Fishing provides 33.3% of GDP on the smaller islands
Who lives in the SEAR?
- Very few live fully isolated due to historic migration and encroachment of modern world
- People are being forcibly moved from crowded countries to the rainforest
- Dani tribe are the main isolated tribe and they hav their own way of life completely without modernity
What are the standard soil horizons?
- Organic- Dead things, worms etc
- Top soil- where organic layer is breaking down into soil
- Sub soil- Thickest layer with lots of processes
- Soil and broken bedrock- Broken mostly through water
- Bedrock- Solid rock with no soil
What a re the soil horizons like in a rainforest?
- Organic and top soil is thin and infertile due to high rates of decomposition (hot, humid conditions)
- Subsoil and soil and bedrock are heavily leached of nutrients due to rainfall
- Bedrock has soft sands and clay deposits which are nearly 13,000 feet deep in some places
What are the causes of tropical deforestation?
- Growing population
- Logging industry
- Energy production
- Transport (e.g trans Amazonian highway)
- Agriculture
- Quarrying
What are the main impacts of tropical deforestation?
- Contributes to climate change: Massive carbon stores, logs burned release CO2, machinery burns fossil fuels
- Loss of biodiversity: Destroys habitats,animals no longer have a home and die
- Economic development: Gives lots of people jobs initially but when profits dry up they move on and there is suddenly no infrastructure
- Soil erosion: No roots holding soil together causes it to erode, reduces fertility and loses nutrients
