The Living World Flashcards
What is an ecosystem?
a place where living organisms interact with their environment
What is an organism?
a living thing
What does biotic mean?
the biotic part of an ecosystem is the living part
What does abiotic mean?
the abiotic part of an ecosystem is the non living part
What is a producer?
an organism that uses sunlight to produce its food
What is a consumer?
an organism that eats another organism
What is a decomposer?
an organism that gets its energy from breaking down dead material
What is a food chain?
a diagram that shows what eats what
What is a food web?
a diagram that shows overlapping food chains
What happens in the nutrient cycle?
Nutrients stored in the soil are taken up by plant roots and stored in the plant. Eventually the plant dies and falls to the ground as litter. The nutrients are then stored here. Decomposers break down the litter for energy so the nutrients go into the soil. Where they are stored again so new plants can take them up.
What is an example of a small scale ecosystem?
Hedgerow
(location: UK)
What are abiotic components of a hedgerow?
- Temperate (not extreme) climate
- Rich fertile soils / brown earths
What are the biotic components of a hedgerow?
- Producers: Hawthorn (the hedge) + blackberry bushes
- Consumers: Ladybirds, thrush, blackbird, sparrow hawk, caterpillars, badgers, mice
- Decomposers: worms
What are examples of how organisms survive in the hedgerows?
- mice use the hedgerow to hide from their predators
- the sparrow hawk is a secondary consumer and eats mice
- the thrush is a primary consumer and eats blackberries
- the blackbird nests in the hedge and also finds it’s food here
- hawthorn is a producer, it gets energy from the sunlight and nutrients from the soil
- caterpillars are primary consumers that eat blackberries
- nutrients found in the fertile brown earth are there because composers like bacteria break down the litter
What is a biome? (examples)
A global scale ecosystem
e.g. (hot) desert, tropical rainforest, temperate (deciduous) forest, tundra, taiga (boreal/coniferous forests), tropical grasslands, polar desert
Where are (hot) deserts found globally?
On and around 30° North and South of the equator
e.g. Northern Africa, Sahara, Central Australia, Southwest USA
What is the climate of (hot) deserts?
Hot – 30° North and South – rays concentrated over small area
Dry – high-pressure so air sinks – clouds dont form
What are the soils like in (hot) deserts?
(summarised)
- called Aridisols – thin, not very fertile as little
- few plants so few nutrients go into the soil in nutrient cycle
What is the vegetation like in (hot) deserts?
- Little vegetation as lack of water
- Shrubs and cactus adapt to lack of water - can absorb water in stem
Where are tropical rainforests found globally?
On and around the equator
E.g. north of South America – Amazon, Southeast Asia, central Africa
What is the climate of tropical rainforests?
Hot – close the equator – rays concentrated over small area, roughly stays the same temperature at 27°C
Wet – low pressure so air rises – clouds form – more than 2000 mm of rain
What is the soil like in tropical rainforests? (summarised)
- soil is not very fertile as nutrient cycle is very rapid due to ideal conditions for growth
- nutrients washed away by water
What is the vegetation like in tropical rainforests? (summarised)
- 15 million species - high diversity - hot and wet conditions – perfect for growth
- Tall trees (up to 40 metres)
- Buttressed bases for support
- Evergreen with large, dark green, leathery leaves
Where are temperate (deciduous) forests found globally?
40° - 60° North
e.g. western Europe
What is the climate of temperate (deciduous) forests?
Mild – 60° North and South – rays spread out over large surface area
Wet – low pressure so air rises – clouds form
What are the soils like in temperate (deciduous) forests?
Brown earths – fertile
What is the vegetation like in temperate (deciduous) forests?
- Trees e.g. ash and oak - deciduous
- Fertile soils and mild climate means lots of growth
- Loose leaves in autumn to prevent water loss
- Bluebells grow in spring when sunlight gets to forest floor
Where are tundras found globally?
On and around the Arctic Circle
E.g. North Russia , North Canada
What is the climate of tundras?
Little rain – high pressure – often falls as snow
Cold temperatures - average 10°C
What are the soils like in tundras?
Soil frozen – permafrost – stops regrowth – only top metre not – soil off and wet – little evaporation
What is the vegetation like in tundras?
Low species diversity – not many plants – climate not good for growth
- Low-lying to protect from wind
- short growing season
- leathery leaves to prevent water loss
Where are taigas (boreal/coniferous forests) found globally?
45-57° North
What is the climate of taiga (boreal/coniferous forests)?
- Cool to cold in winter – warmer in summer
- Rain in summer
What are the soils like in taiga (boreal/coniferous forests)?
Deep litter layer as little decomposition – too cold
What is the vegetation like in taiga (boreal/coniferous forests)?
- Evergreen trees
- Needles to prevent water loss as times of year when little water
e.g. Black and white spruce
Where are tropical grasslands found globally?
On edges of deserts
e.g. East of Africa, Mexico
What is the climate of tropical grasslands?
- Hot all year round – not much rain and it tends to fall in one season
- Often has periods of drought and fires
What are the soils like in tropical grasslands?
Porous thin layer of humus
What is the vegetation like in tropical grasslands?
Grasses and shrubs – can lack water at times
Where are polar deserts found globally?
Very high latitudes
North/South pole
What is the climate of polar deserts?
Cold – 90° north and south – rays spread out over large surface area
Dry – high pressure air sinks – no clouds
What are the soils like in polar deserts?
very little soil
mainly bare rock
What is the vegetation like in polar deserts?
occasionally plants grow in cracks in rock
e.g. arctic poppy
What is biodiversity?
the variety of different species living in an ecosystem
Describe the soils in a tropical rainforest.
- They are red as they contain lots of iron.
- They are deep but not fertile as the heavy rain washes away the nutrients.
- They have a deep litter layer because they have an all-round growing season so plants are constantly dropping their leaves.
- They have a thin humus layer because the leaves decompose quickly and the plants take up the nutrients quickly.
Describe the vegetation in a tropical rainforest.
Vegetation grows in distinct layers, in each layer the plants are adapted to the conditions so there are lots of different species.
They evergreen – even though they look deciduous because they grow all year round so there are lots of plants and animals because there is high primary productivity.
What are the 4 ways leaves are adapted to a tropical rainforest?
- drip tips
- large surface area
- waxy surface
- arrangement
What are the 5 plant adaptations to the rainforest?
- leaves
- roots
- trees
- epiphytes
- lianas
How are leaves adapted to the rainforest?
- because of heavy rainfall, plants need to shed water to avoid growth of fungus and bacteria
- because bacteria likes hot and wet climate so leaves would rot – thats why they have drip tips + waxy suface, so the bacteria doesn’t grow otherwise it would decrease photosynthesis on the leaves
- Arranged at different angles so a plant avoids shading each other
- large surface area to get most sunlight which it uses to photosynthesise
- high levels of biodiversity to there is competition for light
How are roots adapted to the rainforest?
buttress roots
- trees have very shallow roots
- these roots cannot support tall trees
- so buttress roots are massive and give the tree stability
- they don’t actually go into the soil or take up nutrients
How are trees adapted to the rainforest?
- very tall to reach the sunlight
- fan shaped leaves good for catching sunlight and water
- These leaves are segmented so excess water drains away
- also arranged at different angles so avoids shading
- bark isn’t thick – it’s thin and smooth because it makes it harder for other plants to grow on it and it doesn’t need to keep moisture in so is thin
What are epiphytes?
- plants that grow on other plants so can reach the sun
- plants which live on the branches of trees high up in the canopy
How are epiphytes adapted to the rainforest?
- Plants that grow on other plants to reach sunlight
- Start at the top
- Grows on trees to take advantage of the sunlight in the canopy
What are lianas?
woody vines that have roots in the ground but climb up the trees to reach the sunlight
How are lianas adapted to the rainforest?
- vines that climb up trees and drape over them
- Roots on the ground and climb up high (climb up from the bottom) to reach the sunlight
What are the 4 animal adaptations to the rainforest?
- camouflage
- creating niches
- living in trees
- being nocturnal
How does camouflage help animals adapt to the rainforest?
- camouflage is used to avoid becoming prey
- e.g. sloths moves very slowly and spend time upside down on trees making it harder to spot them
-
blue-green algae grows on its fur giving the sloth a greenish colour making it more difficult for predators to spot
🦥
How does creating niches help animals adapt to the rainforest?
- because there are so many animals competing for food, many animals have adapted by learning to eat a particular food eaten by no other animal - this is called creating niches
- e.g. toucans have adapted by developing long, large bills so they can break open hard nuts that other animals can’t
🥜🦤
How does living in trees help animals adapt to the rainforest?
- many animals and insects in the rainforest live in the trees and never set foot on the ground
- the animals use the tall trees and understory for shelter, hiding places from their predators, and a source of food
- e.g. monkeys 🐒
How does being nocturnal help animals adapt to the rainforest?
- many animals have adapted to a nighttime life in order to survive
- e.g. Amazon tree boa avoid predators that are active during the day like birds of prey and primates by sleeping during the day
- at night they hunt other nocturnal animals like rodents using special infrared receptors located in their mouth
- hunting at night also means there’s less competition for food
🐍
What is the location of the Amazon rainforest?
- The Amazon Rainforest is in the North of South America.
- Most of it is in Brazil, although the edges of it spread into countries including Peru, Bolivia and Suriname
What are the 7 causes of deforestation?
- Logging -> trees are used for e.g. furniture, fuel, charcoal
- Road building -> brings supplies + provides access to areas
- Mineral extraction -> mining
- Energy development -> high rainfall creates ideal conditions for hydroelectric power (dams)
- Settlement + population growth
- Cattle ranching
- Commercial farming -> arable
What is logging (deforestation)?
- Trees like mahogany and teak are used for furniture + other uses
- smaller trees are used for fuel, pulped or made into charcoal
What is road building (deforestation)?
- Roads bring supplies + provide access to new mining areas, new settlements + energy projects
- In Brazil, the trans-Amazonian highway stretches for some 4,000 km through the rainforest
What is mineral extraction (deforestation)?
This is a major cause of deforestation in many countries
In Brazil, minerals such as gold bauxite and copper mind extensively, causing huge scars in the landscape + polluting rivers
What is energy development (deforestation)?
High rainfall creates ideal conditions for hydro-electric power and there are several large dams + reservoirs
- In Brazil the Belo Monte dam
(opened in 2019) is a huge hydro-electric power complex, the 2nd largest in the country - In damming the Xingy River, a tributary of the Amazon, 40,000+ hectares of rainforest have been flooded
What is settlement + population growth (deforestation)?
- Settlements have developed to service the developments in the Brazilian rainforest
- Such as farming + mineral extraction
- This has led to a growth in population
What is subsistence +commercial farming (deforestation)?
- Land is cleared for commercial farming
- In Brazil, cattle ranching accounts for 80% of deforestation
- Soybeans, palm oil + sugar cane are the major crops
What are some general facts about Rainforests?
- Rainforest are home to 2/3 of the worlds plant species
- Rainforest cover 6% of the Earth’s surface
- Rainforests are home to 30 million species
- 12-15 hectares of forest are lost each year (36 football field a minute)
What are some facts about the Amazon Rainforest?
- The Amazon covers 5.5 million km² (about 40% of South America)
- The Amazon River is the 2nd longest river on Earth
- Over 20% of the worlds oxygen comes from the Amazon alone
- 350+ indigenous groups live in the Amazon
- On average, 160 inches of rain falls in the rainforest each year
- In the Amazon Rainforest, there are 4,100 miles of rivers
How does deforestation lead to a loss of biodiversity?
- Deforestation reduces biodiversity.
- This affects not only plants and animals in the rainforest, but also humans.
- For species in the rainforest, the loss of biodiversity can disrupt food chains and interdependent relationships.
- For humans, rainforests can be useful for medicine, food and more, so with loss of biodiversity, humans have less of this.