Ecosystems - section B (p1) Flashcards
Define ‘ecosystem’
A natural system made up of plants and animals (biotic) that interact with non-living organisms such as soil, air and water (abiotic)
What is a producer?
An organism that uses the sun to produce energy. e.g. green plants
What is a consumer?
An organism that gets its energy by eating another organism i.e. it eats other producers or consumers.
What is a decomposer?
An organism that gets its energy from breaking down dead material (dead plants and animals). An example of a decomposer is bacteria and fungi
What is a food chain?
A food chain shows what eats what in an ecosystem.
What is a food web?
A food web is a series of food chains within an ecosystem and how they overlap. It shows the interconnections between producers and consumers in an ecosystem.
Describe a nutrient cycle in simple terms
- When plants and animals die, they decompose into the soil.
- They add nutrients back to the soil
- These nutrients are then taken back up by plants
- These plants may be eaten by consumers, therefore the nutrients are received by the consumer
- The consumer eventually dies and nutrients are added back to the soil.
- The cycle repeats
Name some changes that can impact an ecosystem
- Extreme weather - e.g. droughts
- Trimming hedgerows
- Draining ponds
- Deforestation
- Fertilizers used in farming
What is eutrophication and what causes it?
The use of fertilizers on farms leads to eutrophication.
- Nutrients from fertilizers end up in water systems
- Plants grow quickly because of the nutrients
- Algae grows quickly, using up oxygen in water
- Plants and animals in water then die due to lack of oxygen
- Decomposing animals use further oxygen
- Eventually no life possible
Give an example of how one change can impact an ecosystem
- Higher temperatures and less rain = less plants grow = less food for consumers = consumer numbers fall
- Vegetation removed = less habitats for animals = alters animal/vegetation balance in ecosystem
- Deforestation = destorys birds habitats and alters nutrient cycle
What determines the ecosystem found in a place?
Climate
Climate is influenced by: latitude, air pressure (high or low pressure) and winds.
Name the 8 main global ecosystems
- Hot desert
- Tropical rainforest
- Polar
- Tundra
- Temperature deciduous forest
- Tropical grassland (savanna)
- Temperate grassland
- Coniderous forest (taiga)
Describe the characteristics of tropical rainforests?
(location, climate, plants, animals?)
- Found around equator
- Hot temperatures (around 28°-30°c)
- Wet all year around (average 2,000mm per year)
- Lots of vegetation
- Variety of animals
Describe the characteristics of deciduous forests?
(location, climate, plants, animals?)
*This the biome of the UK*
- Location; ~40°-50° north of equator
- Warm summers, cold winters
- Leaves fall off during winter to retain moisture
- Variety of woodland animals
Describe the characteristics of coniferous forests (taiga)?
(location, climate, plants, animals?)
- Location:~50°-60° north of equator
- Cool temperatures
- High rainfall
- Animals: Moose, reindeer, shrews
- Plants: evergreen trees
Describe the characteristics of tropical grassland (savanna)?
(location, climate, plants, animals?)
- Location: 15°-30° north and south of equator
- Wet and dry seasons
- Temperature: 20-30°c
- Animals: lions, elephants
Describe the characteristics of tundra?
(location, climate, plants, animals?)
- Location: 60°-70° north equator (lack of land in southern hemisphere for tundra to be here)
- Cold (Max 10°c, min -50°c)
- Dry (less than 380mm pear year)
- Limited vegetation
- Animals: caribou
Describe the characteristics of hot deserts?
(location, climate, plants, animals?)
- Location: 15° and 35° north and south of the equator
- Very hot
- Very dry
- Sandy soil.
- Some cacti
