Paper 1: Living with the physical environment

Q2 Section B: Living World

Revision of ecosystems

This is revision so you will need to use your Living World homework tasks to help you complete some or all of these tasks. If you find you are missing work see your teacher or borrow the notes. If you are unsure of the work, ask for help. Work needs to be fully completed and handed in on time.
Revision is the key to doing well in your examinations - the more effort you put in, the better you will understand the work in readiness for your Paper 1 examination.
You will need to make some tables bigger so check that before you print the work.
Key term / Definition (include examples/illustrations/diagrams to help you)
Ecosystem (remember to include the useful diamond shaped diagram)
Biotic
Abiotic
Micro ecosystem
Meso ecosystem
Macro ecosystem
Biome ecosystem
Food chain
Food web
Producers
Primary consumers
Secondary consumers
Scavengers
Decomposers
Biodiversity (see rainforest homework task)
Nutrient cycle (see rainforest homework task)
Hot desert (see hot desert homework)
Desertification (see desertification homework)
Social effects
Economic effects
Environmental effects
Humus (see ecosystems homework)
Latosol (see ecosystems homework)
Appropriate technology (see desertification homework)
Explain how humans affect food webs in a freshwater pond. Use examples from the homework to help you.
Explain how natural factors affect food webs in a freshwater pond. Use examples from the homework to help you.

Map to show the distribution of the world’s biomes (global ecosystems)

Biome / Describe the distribution of each biome
Hint: Distribution means how spread out they are (even/uneven, use latitude lines, continents, compass directions, coasts)
Tropical rainforests
Deserts
Temperate deciduous forests

The characteristics of biomes (large scale natural global ecosystems): CLIMATE and SOILS

Climate

Biome / Climate graph / Description of climate
Hint: Use highest, lowest, numbers, seasons
Tropical rainforests /
Deserts /
Temperate deciduous forests /

Soils

Tropical rainforests: LATOSOL

Use the information (and your homework) to draw out a soil profile in the box below. Hint: Annotate depth, layers, colours.

·  Rainforest soils are called LATOSOLS.
·  Latosols are very deep (20 – 30 metres deep).
·  At the top there is a thin black humus layer. The humus layer is the dark organic matter that forms in the soil when plant and animal matter decays.
·  Most of the nutrients in this soil are found in this top humus layer because dead leaves decay quickly in the hot and humid conditions.
·  The heavy rainfall dissolves and washes away these nutrients leaving an infertile soil. This is called leaching.
·  The soil is a rusty orange colour because oxides of iron and aluminium remain in the soil after other minerals have been washed out by leaching.

Desert soil

Use the information (and your homework) to draw out a soil profile in the box below. Hint: Annotate depth, layers, colours.

·  Desert soils tend to be sandy or stony with little organic matter (only a very thin humus layer at the top of this soil) because there is a lack of vegetation to drop their leaves.

·  It is very dry so vegetation that does drop to the floor does not rot very quickly.

·  Any nutrients that do go into the soil are not leached (washed away) as there is so little rainfall.

Temperate deciduous forests

Use the information (and your homework) to draw out a soil profile in the box below. Hint: Annotate depth, layers, colours.

·  Temperate deciduous soils are called brown earth soils.

·  They are not as deep as latosols - 20-30 centimetres

·  Brown earth soils have a deeper humus layer than latosols or desert soils because deciduous trees lose their leaves in Autumn and then rot in the mild and wetter Winters.

·  Some leaching does happen because of the wet climate but slower than the latosols. This means nutrients are held in the soil so they are fairly fertile soils.

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