1. NUTRIENT CYCLES

2. GEOCHEMICAL CYCLES Movement of a particular form of matter through the living and nonliving parts of an ecosystem Earth is a closed system…must continually recycle essential matter (Matter is neither created nor destroyed)

3. THE CARBON CYCLE Carbon is especially important to living systems because it is the key ingredient in all living organisms…Proteins, carbohydrates, lipids, nucleic acids Carbon is especially important to living systems because it is the key ingredient in all living organisms…Proteins, carbohydrates, lipids, nucleic acids

4. PROCESSES IN THE CARBON CYCLE Photosynthesis Photosynthesis Respiration Respiration Decomposition of plants and animals Decomposition of plants and animals Conversion of biochemical compounds Conversion of biochemical compounds

5. OTHER PROCESSES IN THE CARBON CYCLE Combustion Combustion When wood or fossil fuels are burned, CO 2 is released into the atmosphere When wood or fossil fuels are burned, CO 2 is released into the atmosphere

6. OTHER PROCESSES IN THE CARBON CYCLE Weathering of carbonate rocks Weathering of carbonate rocks Bones/shells fall to the bottom of oceans/lakes & are incorporated into sedimentary rocks Bones/shells fall to the bottom of oceans/lakes & are incorporated into sedimentary rocks When they decompose, Carbon is released into ocean, atmosphere When they decompose, Carbon is released into ocean, atmosphere

9. THE NITROGEN CYCLE Why do we need nitrogen? Why do we need nitrogen? Nitrogen is necessary for organisms to make amino acids… Nitrogen is necessary for organisms to make amino acids… …which are needed to build proteins!!!

10. NITROGEN RESERVOIRS In the atmosphere as elemental nitrogen (N 2 ) In the atmosphere as elemental nitrogen (N 2 ) 78% of the air is N 2 gas 78% of the air is N 2 gas In living organisms as proteins or nucleic acids In living organisms as proteins or nucleic acids In organic materials that compose soil In organic materials that compose soil

11. PROCESSES IN THE NITROGEN CYCLE NITROGEN FIXATION: NITROGEN FIXATION: Nitrogen fixing bacteria-found in soil, root nodules of plants Nitrogen fixing bacteria-found in soil, root nodules of plants Convert elemental nitrogen into forms that are available for use by plants Convert elemental nitrogen into forms that are available for use by plants They “fix” it for the plants They “fix” it for the plants

12. PROCESSES IN THE NITROGEN CYCLE NITROGEN INTAKE: NITROGEN INTAKE: Plants take in nitrogen through root systems in the form of ammonia or nitrate Plants take in nitrogen through root systems in the form of ammonia or nitrate This is how nitrogen enters the food chain. This is how nitrogen enters the food chain.

13. PROCESSES IN THE NITROGEN CYCLE DECOMPOSITION: DECOMPOSITION: When an organism dies or animals produce waste products When an organism dies or animals produce waste products Decomposers return nitrogen to the soil Decomposers return nitrogen to the soil

14. PROCESSES IN THE NITROGEN CYCLE DENITRIFICATION: DENITRIFICATION: Denitrifying bacteria break down nitrogen compounds in the soil Denitrifying bacteria break down nitrogen compounds in the soil Release elemental nitrogen into the atmosphere Release elemental nitrogen into the atmosphere “De” undo, reverse “De” undo, reverse

18. THE WATER CYCLE AKA: THE HYDROLOGIC CYCLE Water is a necessary substance for the life processes of all living organisms

19. THE WATER CYCLE AKA: THE HYDROLOGIC CYCLE PRECIPITATION: PRECIPITATION: The process in which water (in the form of rain, snow, sleet, or hail) falls from clouds in the sky. The process in which water (in the form of rain, snow, sleet, or hail) falls from clouds in the sky.

20. THE WATER CYCLE AKA: THE HYDROLOGIC CYCLE EVAPORATION: EVAPORATION: Water changing from a liquid to a gas Water changing from a liquid to a gas TRANSPIRATION: TRANSPIRATION: Evaporation of water from a plant’s leaves Evaporation of water from a plant’s leaves

21. THE WATER CYCLE AKA: THE HYDROLOGIC CYCLE CONDENSATION: CONDENSATION: Water vapor (a gas) in the air turns into liquid water. (Condensing water forms clouds in the sky.) Water vapor (a gas) in the air turns into liquid water. (Condensing water forms clouds in the sky.) As water vapor condenses— impurities (such as dust) are removed from the atmosphere and fall to Earth with precipitation As water vapor condenses— impurities (such as dust) are removed from the atmosphere and fall to Earth with precipitation

22. THE WATER CYCLE AKA: THE HYDROLOGIC CYCLE ACCUMULUATION: ACCUMULUATION: Water pools in large bodies (oceans, seas and lakes). Water pools in large bodies (oceans, seas and lakes). SEEPAGE: SEEPAGE: Water entering the ground Water entering the ground

23. THE WATER CYCLE AKA: THE HYDROLOGIC CYCLE RUN-OFF: RUN-OFF: As water travels through soil and rock, it is physically filtered of impurities (filtration) As water travels through soil and rock, it is physically filtered of impurities (filtration) Water flow slows—heavier particles settle out and purified water continues toward oceans Water flow slows—heavier particles settle out and purified water continues toward oceans

24. THE WATER CYCLE AKA: THE HYDROLOGIC CYCLE Also remember… Also remember… Water is also returned to the environment during cellular respiration! Water is also returned to the environment during cellular respiration! C 6 H 12 0 6 + O 2 CO 2 + ATP + H 2 O

27. O 2 -CO 2 balance…plants need to produce enough O 2 O 2 -CO 2 balance…plants need to produce enough O 2 Oxygen produced by plants is also responsible for the ozone layer Oxygen produced by plants is also responsible for the ozone layer Prevents much of the Sun’s UV radiation from reaching Earth’s surface Prevents much of the Sun’s UV radiation from reaching Earth’s surface

28. The story of my fish tank…

29. AMMONIA (NH 3 ) is released through respiration & excretion Ammonia is very deadly in high concentrations—so enough fish producing ammonia in a small space (like an aquarium)…will kill the fish.

30. Well, this doesn’t have to happen… Well, this doesn’t have to happen… Bacteria present in an aquarium will feed on ammonia producing nitrites…another bacteria will feed on nitrites producing nitrates… Bacteria present in an aquarium will feed on ammonia producing nitrites…another bacteria will feed on nitrites producing nitrates… Nitrates are not nearly as harmful, and much, much easier to control. You would need OBSCENE amounts for it to do any real damage. Nitrates are not nearly as harmful, and much, much easier to control. You would need OBSCENE amounts for it to do any real damage.