Fichas
Lecture 8
Fichas del conjunto (6)
- 1Nitrogen FixationFixated by soil bacteria and in the root modules of legumes
N2 -> NH4 - 2NitrificationInorganic nitrogen NO3 and NO2 formed
NH4 -> NO2 + NO3 - 3AssimilationPlants and phytoplankton uptake DIN (NO2 + NO3) and DON (amino acids)
- 4AmmonificationOrganic
(urine, faeces and dead organisms)
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Inorganic (NH4) - 5DenitrificationWithout this process, most of N would be NO3 in sea water, making the seas more acidic.
NO3 -> N2 (gas in atmosphere) - 6Human impacts on the Nitrogen CycleEutrophication
Humans fix as much N2 as the biosphere does
Draining wetlands
decreases potential for denitrification
Biomass and burning fossil fuels produces nitrogen oxides involved in aced rain and ozone chemistry