Nitrogen cycle (Pt.2)

Nitrogen fixation involves the conversion of dissolved nitrogen gas to organic nitrogen compound carried out mainly by cyanobacteria. Dissolved organic nitrogen (DON) and particulate organic nitrogen (PON) both serve as nutrients for bacterial growth. Bacteria break down proteins to amino acids & ammonia, & the ammonia is then oxidised during nitrification. The eventual release of dissolved inorganic nitrogen (DIN) makes these forms available again for uptake by the phyt.