Nutrient Cycles

Carbon Cycle

Image: fig.cox.miami.edu

Carbon Cycle

• CarbonCycle Animation

• Tutorial 58.2 The Global Carbon CycleAnimation

The Carbon Cycle Game This would make a nice simulation!

Global Warming Mini Video

• http://www.ecobridge.org/video/Quicktime/256.mov

Nitrogen Cycle

• Why do we need nitrogen?

• For DNA, RNA, Proteins

Where does Nitrogen Come From?

• Five main processes cycle nitrogen through the biosphere, atmosphere, and geosphere:

• 1. nitrogen fixation• 2. nitrogen uptake (organism growth) • 3. nitrogen mineralization (decay) • 4. nitrification• 5. denitrification

1. Nitrogen Fixing: Changing unusable nitrogen into usable

nitrogenN2 NH4+

N2 is converted to ammonium, Essential because it is the only way that organisms can attain nitrogen directly from the atmosphere

ONLY DONE WITHNITROGEN FIXING BACTERIA.

Legume Nodules

• nodules of Rhizobium, bacteria that can fix atmospheric nitrogen.

• UGLY – BUT NEEDED!!!

Nitrogen Fixing Bacteria

2. Uptake by Organisms

• Clover is a low cost source of nitrogen.

Urine, fertilizer add nitrogen

3. Nitrogen Mineralization (Decay)

• Microbes eat the decomposed organisms. There is too much nitrogen for them, so they give off nitrogen as ammonia NH3.

Nitrogen Cycle

4. Nitrification

5. Denitrification

• Nitrogen Cycle Animation

WATCH THE MOVING DOTS

Nitrogen cycle

• Fixation of atmospheric nitrogen, N2

• - electrical discharge, chemical production, biological fixation

• NO3 plants animals death & wastes

• Waste org. N decomposers NH3

• NH3 nitrifiers NO2 & NO3

• NO2 & NO3 denitrifiers N2

Animation

• Tutorial 58.4 The Global Nitrogen Cycle

Phosphorus Cycle

• Phosphorus does not enter the atmosphere in its cycle

• Phosphorus remains mostly in rocks and ocean sediments

• Phosphate is found in DNA and RNA (all living things)

Phosphorus Cycle Animation

• Animation