Living World Flashcards
(40 cards)
How much of the amazon rainforest has been deforested?
750,000km2
Where is the amazon rainforest?
South America
Causes of deforestation in the amazon rainforest?
65-70% commercial cattle farming 20-25% small scale subsistence farming 5-10% commercial farming 2-3% logging 1-2% other eg mining
Economic impacts of deforestation in the amazon rainforest
+ creates jobs for locals eg 3100 in Peru mine
+ economic growth ($6.9 billion in 2008 from cattle in Brazil)
+ taxes paid to be used for improvements in services
+hydroelectric power is cheap and renewable
- destroys the livelihood of indigenous
Environmental impacts of deforestation in the amazon rainforest
- loss of biodiversity
- increase in Co2
- soil erosion = flooding
- decrease in soil fertility
- pollution
Management strategies for the tropical rainforest
Selective logging and replanting, conservation and education, ecotourism and international agreements, debt reduction
What is an ecosystem?
A natural system made up of plants, animals and the environment (biotic and abiotic)
Producers:
Concert energy from sunlight to produce food (create their own energy)
Consumers:
Get energy from eating producers or other consumers
Decomposers:
When dead material is decomposed, they release nutrients into the soil
What is nutrient cycling?
When nutrients are transferred throughout the ecosystem.
What are large scale global ecosystems?
Biomes
What are the characteristics of a TROPICAL RAINFOREST and where are they distributed?
Temp: av= 27C
rainfall= 2000mm
close to equator
hot desert
low rainfall = 250mm yr
high daytime temp
30 degrees N and S of equator
tundra
low temp= can drop to -20
low rainfall
arctic circle = 60-70 degrees N
TR
warm temp
heavy rainfall
infertile soil
dense vegetation
how plants adapt to TR climate
tall to reach light drip tip, waxy so water drains thick buttress so trees stay steady wide root network to get nutrients form soil climbing plants using trees to get light
how animals adapt to TR climate
gripping tail to live in canopy
camouflage to hide in shrub layer
suction pads to grip onto trees
nocturnal to avoid the heat of the day
biodiversity=
the variety of plant and animal species in an ecosystem
TR facts
50% of species
28% of worlds oxygen
25% of medicines
sources of clean water
characteristics of tundra and polar
cold - polar >-0, tundra<10 low rainfall layer of permafrost thin soil few vegetation few species of animals
how do plants adapt to tundra/polar climate
become dormant in cold winters low growing hairy stems to insulate thin waxy leaves to reduce water loss shallow roots short growing season
how do animals adapt to polar/tundra climate
well insulated with thick fur and blubber
hibernate to conserve energy
white fur for camo
survive on limited food
biodiversity in cold environments
low + fragile
=small changes= big impact