TUTOR

• FEATURES OF NITROGEN GAS?

  78% of atmosphere

  Inert

  -> must be converted into a compound
• USES OF NITROGEN?

  • NAD/ NADP
  • ATP
  • nucleotides -> DNA/ RNA
  • AAs -> proteins
• POSITIVE FARMING PROCESSES?

  • ploughing
  • growing legumes
• NEGATIVE FARMING PROCESSES?

  • harvesting plants
  • removing livestock
  • overwatering
• OVERWATERING?

  • soil waterlogged
  • less oxygen
  • anaerobic bacteria increases
  • increase in denitrification
  • decreased nitrification
• HARVETING PLANTS?

  • removes mineral ions from soil
• REMOVING LIVESTOCK?

  • less manure
  • less natural fertiliser
  • decrease in mineral ions
• PLOUGHING?

  • aerates soil
  • more oxygen
  • increased nitrifying bacteria
  • increased nitrification
• GROWING LEGUMES?

  • die and decompose
  • ammonification
  • plough breaks up plants
  • NH4+ released from nodules
  • increased nitrification
• USES OF PHOSPHORUS?

  • NADP
  • ATP
  • nucleotides -> DNA/ RNA
  • phospholipids
• REASONS WHY FARMING HAS NEGATIVE ENVIRONMENTAL IMPACTS?

  1. MONOCULTURES

  • clear land for crops
  • destroy habitats and food sources

  1. HERBICIDES

  • kill weeds
  • lowers species richness
  • destroys habitats and food sources
  • animals cannot survive

  1. FERTILISERS

  • eutrophication

  1. SELECTIVE BREEDING