Ecosystems

• Ecosystem


  All the biotic (living parts) and the abiotic (non-living parts) of an area
• Organisms in ecosystems


  • Producer
  • Consumer
  • Decomposer
• Producer


  Uses sunlight energy to produce food (e.g. grass)
• Consumer


  Gets its energy by eating other organisms (e.g. foxes)
• Decomposer


  Gets its energy by breaking down dead material
• Nutrient Cycle


  1. Dead material decomposes

  2. Nutrients are released into the soil

  3. Nutrients are taken up from the soil by plants

  4. Plants or consumers die, nutrients are returned to the soil

  5. Transfer of nutrients is called nutrient cycling
• Food chain


  Shows what eats what
• Food web


  Lots of food chains and how they overlap
• Decase and deforestation


  Can cause imbalance between ecosystem components leading to extraction of biodiversity
• Polar ecosystem


  • Found in the north and south poles
  • Very cold, icy and dry
  • Remain dark, growing season is very short
• Tundra ecosystem


  • Found in high latitudes
  • Very cold winters, brief summers with little rainfall
  • Permafrost - a layer of permanently frozen ground
• Boreal Forest (Taiga) ecosystem


  • Found 50°-60° N
  • Winters cold and dry, summers mild and moist
  • Trees are coniferous and evergreen with needles
• Temperate Deciduous Forest ecosystem

  • Found in mid-latitudes with 4 distinct seasons
  • Summers warm, winters mild, rainfall all year round
  • Deciduous trees lose their leaves in winter to cope with cold
• Grassland ecosystem


  • Savannah - between the tropics with distinct dry and wet seasons
  • Temperate - higher latitudes with less variation in temperature and rainfall, no trees just grass
• Hot Desert ecosystem


  • Found 15°-35° N and S
  • Little rainfall, day hot, night cold