Reservoirs: Atmosphere (N2 living things can’t use!) Plants/decomposers, soil 1) NITROGEN FIXATION (bacteria/legumes): N2 NH3 and NH4+ 2) NITRIFICATION (bacteria): NH4 NO2- NO3 - 3) ASSIMILATION: plants absorb NO3-… nitrogen is now passed up the food chain! 4) AMMONIFICATION : plants/animals die and NH4+ returns to the soil. living things die and decomposers convert the nitrogen found in the wastes and dead organisms back into ammonia. It can then go back through Nitrification, OR… 5) DENITRIFICATION (bacteria): NO3- N2 returns to atmosphere Phosphorus: needed for nucleic acids Reservoirs: Rocks!, organisms, fertilizer, soil, guano, NOT IN ATMOSPHERE Sulfur: needed for proteins Reservoirs: Ocean sediments, decaying matter, volcanoes, atmosphere
Reservoirs: Atmosphere (N2 living things can’t use!) Plants/decomposers, soil 1) NITROGEN FIXATION (bacteria/legumes): N2 NH3 and NH4+ 2) NITRIFICATION (bacteria): NH4 NO2- NO3 - 3) ASSIMILATION: plants absorb NO3-… nitrogen is now passed up the food chain! 4) AMMONIFICATION : plants/animals die and NH4+ returns to the soil. living things die and decomposers convert the nitrogen found in the wastes and dead organisms back into ammonia. It can then go back through Nitrification, OR… 5) DENITRIFICATION (bacteria): NO3- N2 returns to atmosphere Phosphorus: needed for nucleic acids Reservoirs: Rocks!, organisms, fertilizer, soil, guano, NOT IN ATMOSPHERE Sulfur: needed for proteins Reservoirs: Ocean sediments, decaying matter, volcanoes, atmosphere