Biogeochemical Cycles

1. Biogeochemical Cycles • Carbon and Nitrogen

2. LIFE • Living things contain matter in a highly organized, low-entropy state; they can capture, store, and transmit energy. • Organisms are also capable of reproduction and change through time.

3. The Biological Pump • The biological pump is the process by which CO2 fixed in photosynthesis is transferred to the ocean interior resulting in a temporary or permanent storage of carbon. • This biogeochemical process involving plants, the animals that consume them, and the bacteria that assimilate their waste plays a central role in the global carbon cycle.

4. Biogeochemical Cycles • Natural processes that recycle nutrients in various chemical forms from the nonliving environment to living organisms and then back to the nonliving environment

5. Chemicals used by organisms • Organisms use chemicals in their metabolism • Carbon • Oxygen • Hydrogen • Nitrogen (proteins, nucleic acids)

6. CARBON • The basic building block of life • Carbon enters the atmosphere though; respiration volcanic eruptions release from rocks deep in earth’s crust burning of fossil fuels

7. Photosynthesis • Carbon dioxide is removed from the atmosphere by producers that use CO2, sunlight and nutrients to make food through the process of photosynthesis. • Plants FIX carbon into usable forms (sugar)

8. CO2 Photosynthesis Phytoplankton

9. Respiration • Some CO2 is then released back into the water through respiration as the plankton break down their food to release energy.

10. CO2 Photosynthesis Respiration Phytoplankton

11. Consumption • Some of the carbon is passed on to primary consumers: zooplankton (animal plankton) and other filter feeders that depend on phytoplankton for their energy.

12. CO2 Photosynthesis Respiration Phytoplankton Zooplankton Consumption

13. Decomposition • Bacteria play a vital role in the biological pump by decomposing organic particles such as waste products and dead organisms that sink to the deep sea (Aerobic decomposition releases CO2).

14. Microbial Loop • Dissolved organic carbon (DOC) is used by bacteria • Bacteria is eaten by protozoan • Protozoan are eaten by zooplankton • Zooplankton is eaten by fish • Fish excrete DOC • DOC is eaten by bacteria • And so on…

15. CO2 Photosynthesis Respiration Phytoplankton Zooplankton Consumption Decomposition Bacteria

16. Higher Trophic Levels • Consumption continues to transport carbon through higher trophic levels.

17. CO2 CO2 Photosynthesis Respiration Respiration Phytoplankton Zooplankton Consumption Higher LevelConsumers Decomposition Consumption Decomposition Bacteria

18. Higher Trophic Levels • The process continues…

19. CO2 CO2 CO2 Photosynthesis Respiration Respiration Phytoplankton Respiration Zooplankton Consumption Higher LevelConsumers Decomposition Consumption Decomposition Bacteria

20. Nitrogen • Critical component of proteins, chlorophyll and nucleic acids • Found in the bodies of organisms in different forms…

21. Nitrogen input • Nitrogen is added to the ocean by; river runoff precipitation nitrogen-fixing organisms

22. Useable nitrogen • 48% of dissolved gas in seawater is nitrogen • Organisms can not use free nitrogen • Must be bound to oxygen or hydrogen • Bacteria fix nitrogen (make it bigger) • Plant growth is limited because of the limited source of useable nitrogen

23. Nitrogen and animals • As dissolved organic ions (waste): ammonium NH4+ nitrite NO2- nitrate NO3-

24. Nitrogen and plants • Small oceanic plants use mostly nitrate (fertilizer) • Fish eat the plants and excrete ammonia and urea. • Mulm the technical term for what comes out of the vent • Then bacteria fixes the mulm into useable fertilizer for plants again

26. In an aquarium • Ammonia is in fish waste and is also released through gills when they absorb oxygen (breathe) • Ammonia can be changed into a toxic form called Ammonium depending on pH levels, temperature, and salinity • High levels of ammonium can kill fish

28. 3 KINDS OF FILTRATION USED TO GET RID OF WASTE BIOLOGICAL: Bacteria ingest waste and convert it. CHEMICAL: O3 binds to “junk” in the water and makes it easier to remove. Carbon also removes impurities from the water. PHYSICAL: Water flows through mechanical filter plates and the waste gets trapped.

29. Micron filter and cotton filter

30. Ozone generator and carbon filter

31. Nitrifying Bacteria • Nitrobacter and nitrosomonas (the good kind of bacteria) • Converts ammonia and nitrites into nitrates • Denitrifying bacteria turns nitrates back into nitrites and free ammonia • This keeps the cycle going

32. Nitrosomonas europaea

33. Where the bacteria lives • On any clean, hard surface • Aerobic NEED oxygen • Examples: gravel bioballs filter plates

34. Problems with Aquariums • Temperature • Bacteria populations • Parasites • Stress

35. Parasites • Worms; Nematodes (round worms) Trematodes (hooks and suckers)

36. Nematodes found in gut (usually)

37. Trematodes found in gills or on outside of body.

38. Little parasites… • Ciliated Protozoans; Ichthyopthirius multifiliis (ICH) fresh Cryptocaryon (crypt) salt

39. ICH and CRYPT • Appears as white spots anywhere on a fish • Fish will rub against rocks etc. because its itchy • Very contagious • Spreads rapidly • Is always present but will “take over” if a fish’s immune system is suppressed by; stress, sudden change in temp, etc.

40. Ichthyopthirius multifiliis (ICH)

42. Cryptocaryon (crypt)

43. Treatments (FYI) • If you are treating Ich use a salt water bath • If you are treating crypt use a fresh water bath • If your tank has NO invertebrates you can use a copper solution (but they can build a tolerance to this over time)