1.4 - 1.7 carbon, nitrogen, phosphorus, + hydrologic cycles

nitrogen store

the atmosphere

nitrogen cycle steps

1) nitrogen fixation

2) nitrification

3) assimilation

4) ammonification

5) denitrification

what is nitrogen fixation carried out by?

bacteria, lightning

nitrogen fixation formula

N2 → NH3 (NH4)

nitrogen → ammonia (ammonium)

what is nitrification carried out by?

bacteria

nitrification formula

NH3 → NO2 → NO3

ammonia →nitrite → nitrate

what is assimilation carried out by?

plants

assimilation formula

NO3 → protein

nitrate → protein in food web

what is ammonification carried out by?

bacteria

ammonification formula

protein → NH3

protein → ammonia

what is denitrification carried out by?

bacteria (water logged soil)

denitrification formula

NH3 →N2

ammonia → nitrogen

nitrogen human impact

* synthetic fertilizer = eutrophication
* cars (NO2) = photochemical smog, acid deposition

nitrogen cycle order KEY

Fix NAAD (steps)

A NPAN (products)

carbon stores

* fossil fuels (sink)
* ocean sediment
* biomass (old forest)

carbon cycle steps

(no order)

* photosynthesis
* combustion


* cellular respiration
* fossilization
* decomposition
* diffusion
* sedimentation

carbon human impact

* deforestation, carbon stored in trees released into atmosphere = less photosynthesis removing CO2 from it
* fossil fuel combustion

fossil fuel combustion effects

* global warming
* ocean acidification

which carbon sink holds carbon compounds for the shortest amount of time?

vegetation/biomass

phosphorus stores

* rock
* sediment

phosphorus human impact

use of…

* fertilizers
* mining
* guano

= eutrophication

farming practices that reduce soil erosion have what long term effect on the environment?

less algal growth will occur, because less phosphorus can runoff into waterways, making it available for the algae to use to grow

water stores

* ocean
* ice caps
* glaciers

hydrologic cycle steps

(no order)

* percolation
* evaporation
* infiltration
* condensation
* runoff
* transpiration

water human impact

* reduced percolation
* overuse (from extracting too much water, groundwater depletion)
* destruction of wetlands
* pollution