Use of Fertilisers

• • Fertilisers can be used to provide plants with minerals, particularly nitrates, to support their growth
  • In agriculture systems, the harvesting of crops prevents the reintroduction of minerals to the soil
• • Natural ferilisers consist of dead and decaying remains of plants, animals and their waste
  • Artificial fertilisers are mined from rocks before being converted into different forms with their composition tailored for specific crops.
• Reduced species diversity

  Nitrogen-rich soils favour rapidly growing species

  Leaching (pollutes waterways)

  Rainwater dissolves soluble nutrients (e.g. nitrates) and carries them deep into the soil and into waterways such as streams, rivers and lakes.
• What is the effect of aeration of the soil?

  aerate the soil adds more oxygen

  more aerobic conditions in soil

  prevents denitrification
• Eutrophication

  Nitrate levels increase in rivers and lakes due to leaching. The increased algal growth blocks light reaching the water underneath the surface, killing plants at a lower depth. The population of saprobiontic bacteria increase, respiring and reducing oxygen levels, killing other aerobic organisms like fish.