Eutrophication/Fertilisers

• Fertilisers


  Add nutrients to soil

  e.g nitrates absorbed by plants to make protiens which help growth making bigger leaves so more photosynthesis

  can be natural or artificial
• Natural fertilisers


  cheaper

  less soluble so less leaching

  smell
• Artificial fertilisers 


  more concentrated so less needed

  expensive

  more soluble
• Leaching


  nutrients removed from soil dissolved into water, washed into lakes

  leads to eutrophication
• Eutrophication

  1. increase in nitrate causes algal bloom
  2. algae block light so lower plants die due to lack of photosynthesis
  3. saprophytes break down dead plant material
  4. saprophytes use up oxygen in respiration
  5. fish die due to lack of oxygen to respire