Forests Under Threat Flashcards
Why is biodiversity high in rainforests? 3 reasons
Perfect climate for year round growth
They’re ancient and have a stable climate so thousands of different species have evolved.
Layers are specialised habitats for different species.
What is the equatorial climate like?
Season
Rainfall
Temperatures
No winter or summer
No dry season, at least 60mm of rainfall each month; some get three metres of rain each year
High temps at 26-32°C all year round
Emergent Layer
Hardwood evergreen trees, broken through dense canopy, monkeys live here
Canopy Layer
Dense layer, home to tree snakes, birds, tree frogs and other as food is in abundance
Understory Layer
Young trees and ones with large leaves to capture most sunlight, lots of insects
Forest floor
Due to darkness, shade-loving ferns with large leaves live here alone with mammals e.g. the jaguar
Evergreen hardwood trees - adaptations
Mahogany, teak, ebony trees.
All have slender trunks with no branches, do have huge triangular buttress roots. They support weight of tree.
Leaves and branches at the top where there is sunlight
Epiphytes - Adaptations
Live in the canopy on trees
Get all nutrients from water and air instead of soil.
So their roots dangle in the air
Lianas - adaptations
Climbing plants use trees as their ‘trunk’
The climb to the top to reach sunlight while still getting nutrients from the soil and water on the ground.
Drip tip leaves - adaptations
thick waxy leaves on rainforest trees
drip tips shed water quickly to prevent leaves rotting
Sloths - adaptation
Huge claws allow them to hang upside down.
Fur grows away from their feet to help shed rain when upside down
Green algae growing in fur helps camouflage
Primates - adaptations
Lemurs and monkeys live in the canopy where the most food is.
Strong claws
Big cats - adaptations
Jaguars, tigers and leopards all have camouflaged fur
Birds - adaptations
loud calls as is easier to hear a mate than see in the dense canopy.
parrots and macaws have powerful beaks to break open nuts
Larger biomass store
layers of vegetation and huge trees store large amounts of nutrients
Smaller litter store & larger decay transfer
In hot and wet conditions, bacteria and fungi decay dead matter quickly, returning nutrients to the soil.
Larger growth transfer
Plants grow all year, so draw nutrients up from the soil rapidly
Larger weathering input
Chemical weathering processes are faster in hot wet climates, so release nutrients into the soil from rocks.
Larger leaching output
heavy rainfall throughout the year brings in nutrients, but the constant flow of water through the soil removes them.
What is the order of the food chain in the rainforest?
Primary producers -> primary consumers -> secondary consumers -> tertiary consumers -> detritivores
OR
Plants -> herbivores -> carnivores -> top carnivores -> decomposers
Give 2 examples of organisms at each trophic level in the rainforest.
Plants: trees, ferns, flowers Herbivores: sloths, ants, butterflies Carnivores: birds, frogs Top carnivores: snakes, jaguars Decomposers: fungi, bacteria
Basic Taiga info:
Latitude
Countries
Trees
Between 50-70° latitude, northern hemisphere usually
Found mainly across norther Canada and Russia
Coniferous (evergreen) trees. Shaped so that snow falls instead of weighing down branches. Pine needles prevent damage by wind and snow
Taiga climate:
Summers
Winters
Precipitation
- Short wet summers, temp can rise to 20°C
- Long cold and dry winters, several months below freezing, low as -20°C
- Rainfall is low in winter months (below 20mm) and only gets 350-750mm a year. There is snow on the ground for many months
Why is biodiversity in the taiga low? 2 reasons
- Only specially adapted animals can survive in the cold, so reptiles and amphibians are rare
- Growing season is 4-5 months long meaning food in winter is scarce
