ecosystems

• What is an ecosystem?

  A community of plants and animals that interact with each other and their physical environment.
• Define abiotic


  Relating to non-living parts of an ecosystem.
• What are examples of abiotic parts of an ecosystem?

  Sunlight, temperature, rocks, water, nutrients
• Define biotic


  Relating to living parts of an ecosystem.
• What are examples of biotic parts of an ecosystem?

  Plants, bacteria, animals, fungi
• What is a producer?

  An organism that is able to absorb energy from the sun through photosynthesis.
• What is a consumer?

  An animal that eats animals and/or plant matter.
• What is a decomposer?

  An organism such as a bacterium or fungus, that breaks down dead tissue, which is then recycled to the environment.
• What is a food chain?

  The connections between different organisms (plants and animals) that rely on one another as their source of food.
• What is a food web?

  A complex interconnection of all the food chains in an ecosystem.
• What is our case study of a small scale ecosystem?

  Epping Forest
• What are the producers in Epping Forest?

  Native trees - oak, elm, ash

  Shrub layer with 177 species of moss and lichen
• What are the consumers in Epping Forest?

  Birds: 38 species

  Mammals such as Rabbits and foxes
• What are the decomposers in Epping Forest?

  Fungi: 700 species
• How does eutrophication take place?

  Fertilisers contain nitrates

  Nitrates dissolve in rain and wash into ponds

  Rapid algae growth in ponds

  Algae decays, using up oxygen

  Oxygen levels fall Marine life dies
• How does one aspect of the ecosystem changing affect the rest?

  What it eats - will longer be eaten / will be overeaten

  What it is eaten by - will have too much food / not enough
• What is a global ecosystem?

  A very large ecological area on the earth's surface, with fauna and flora (animals and plants) adapting to their environment.
• How does Global atmospheric circulation impact on biome distribution?

  At the equator: Air rises, high insolation

  Rainforests - hot and wet

  At 30° NS - Air sinks, high insolation

  Deserts - hot and dry

  At 60° NS - Air rises, lower insolation

  Taiga - colder and wet

  At 90° NS - Air sinks, low insolation

  Tundra - colder and dry
• What is the tropical rainforest like?

  Hot and wet

  Dense vegetation, high biodiversity

  Conditions that allow plants to grow
• What is the savanna like?

  Warm, with wet and dry seasons

  Grasses and scrub
• What is the desert like?

  Very dry, with hot days and cold nights

  Sparse vegetation, as conditions do not allow plants to grow
• What is grassland like?

  Hot summers, cold writers, some minor rain

  Mainly grasses, no trees - not enough rain
• What is a temperate forest like?

  Four seasons, colder climate

  Very dense trees which lose their leaves (deciduous)
• What is the taiga like?

  Long cold winters, mild summers.

  Evergreen trees
• WHat is the tundra like?

  Cold dry conditions - limited rain

  Mosses and shrubs - harsh conditions
• What is nutrient cycling?

  A set of processes whereby organisms extract minerals necessary for growth from soil or water, before passing them on through the food chain - and ultimately back to the soil and water.
• How does the nutrient cycle work?

  Nutrients enter the system through

  Water from precipitation

  Rocky subsoil

  Leave the soil through

  Plants absorbing nutrients and using them to grow

  Return to soil through

  Decomposing into the soil

  Being broken down by decomposers
• What is the nutrient cycle like in Epping Forest?


  Large biomass store

  Large soil store

  Lots of flow between them
• How are nutrients lost in Epping Forest?

  Runoff - when they are washed out of the litter layer by rain

  Leaching - when they are washed out of the soil by rain
• How are ecosystems fragile?

  They are very sensitive to change
• How does deforestation impact ecosystems?

  Less trees - biodiversity decreases

  The soil is no longer protected

  Exposed to precipitation

  Soil erodes —- biodiversity decreases

  Soil is washed into rivers and they silt up

  Flood risk and marine life affected
• What is eutrophication?


  Excessive growth of algae