Ecosystems

• Ecosystem


  A complex natural system made up of plants, animals and the environment
• Biome


  Global ecosystems
• Elements of an ecosystem

  • Producers
  • Consumers
  • Decomposers
  • Nutrient cycling
• Producers

  • Plants - convert energy from the sun by photosynthesis
• Consumers


  • Get their energy from eating producers
• Decomposers


  • Break down dead plants and animals to add nutrients to the soil
• Nutrient cycling


  1. Plants take in nutrients to build into new organic matter

  2. Nutrients are taken up when animals eat plants and then returned to the soil when animals die
• Changes in one part of the ecosystem

  Can change the balance
• Scales of ecosystem change

  • Local
  • Global
• Causes of ecosystem change

  • Natural causes (extreme weather)
  • Human activities (woods cut down, farming)
• Abiotic

  Non-living part of the ecosystem (air, water)
• Biotic


  Living parts of the ecosystem (plants, animals)
• Flora

  Plant life
• Fauna

  Animal life
• Small scale ecosystem in the UK

  • Pond
• Components of a pond ecosystem

  • Pond surface- plenty of light and oxygen
  • Above the pond surface – birds an animal breath oxygen
  • Pond margin – plenty of light and oxygen here
  • Mid water – animals breath through gills or skin
  • Pond bottom – little oxygen or light
• Examples of global biomes

  • Tropical rainforest
  • Tropical grassland
  • Hot desert
  • Temperate forests
  • Tundra
  • Coral Reefs
• Biomes are distributed in broad belts across the world from west to east, parallel to lines of latitude
• The climate and characteristics of biomes are determined by global atmospheric circulation