1. Matter cycles
• Organisms are reservoirs of these atoms, in various forms
• Organisms are part of the cycling of these atoms, via various metabolic processes

2. water cycle
Reservoir: most locked in oceans; limited fresh water for life

3. water cycle Abiotic: evaporation, condensation, precipitation cycle
• transpiration – water moves through plants from roots to leaves, then to atmosphere; keeps plants upright
• moved into organic molecules via photosynthesis
• produced in respiration as sugars -> ATP

4. carbon cycle Reservoir: • CO2 in the atmosphere
(0.03% of atmospheric gases)
• A greenhouse gas, blocking the escape of long wavelength terrestrial radiation
• Increased CO2 is correlated with increased global temperatures

5. carbon
Biotic:
• C brought into ecosystem producers, as CO2, via photosynthesis
• Transferred between organisms in feeding relationships and returned to abiotic reservoirs via respiration
• Incomplete decomposition created organic C deposits - the non-renewable, CO2 releasing fuels of today
Abiotic:
• CO2 in atmosphere
• oceans are CO2 sinks, but how
much?
H20 + CO2 -> carbonic acid

6. phosphorous
Reservoir: locked in rocks & sediment

7. phosphorous
Biotic:
• Stored in organisms in cell membranes, ATP, nucleic acids
• Low availability limits plant growth
Abiotic:
• continental rocks & sea floor sediments
• slow release means limited availability in in soil

8. nitrogen
Reservoir: N2 in atmosphere

9. nitrogen
Biotic:
• Used by organisms to construct proteins, nucleic acids
Abiotic:
• atmospheric form (N2) inaccessible to most organisms
• little available in soil

10. nitrogen • or NH4+ ->N2 released to the atmosphere Denitrification
• Bacteria in legume roots turn N2 -> NH3 creating soil source of N for plants nitrogen-fixation 4 1 2 3
• In decomposition organically-bound
N -> NH4+ ions ammonification
• NH4+ -> nitrates/ nitrates in soil to be used by more plants nitrification

11. eutrophication
• P, N are limiting factors for plant growth, therefore add to fertilizers
• runoff introduces P, N to waterways, causing excessive plant growth, aka eutrophication
• subsequent decomposition of plant mass robs water of oxygen, affecting fish and aquatic invertebrate populations

12. eutrophication