CHAPTER 13 Biological Productivity and Energy Transfer

1. CHAPTER 13Biological Productivity and Energy Transfer Fig. 13.5

2. http://www.oxygentimerelease.com/A/imagesa/phytoplankton.jpg Primary productivity • Rate at which energy is stored in organic matter • Photosynthesis using solar radiation • 99.9% of marine life relies directly or indirectly on photosynthesis for food • Chemosynthesis using chemical reactions http://www.ocean.udel.edu/deepsea/level-2/chemistry/magnified.jpg

3. Photosynthetic productivity • Chemical reaction that stores solar energy in organic molecules Fig. 13.1

4. Photosynthetic productivity • Gross primary production • Total amount of organic carbon produced by photosynthesis per unit time in certain area • Net primary production • Gross primary production minus cellular respiration (growth, reproduction) • NPP = GPP – Respiration • New production • Nutrients added to local ecosystem (e.g., upwelling) • Regenerated production • Recycling of nutrients within ecosystem http://www.ecologyandsociety.org/vol1/iss2/art2/fig6.gif

5. Measuring primary productivity • Capture plankton • Plankton nets • Ocean color • Chlorophyll colors seawater • SeaWiFs on satellite

6. Factors affecting primary productivity • Nutrients • Nitrate, phosphorous, iron, silica • Most from river runoff • Productivity high along continental margins • Solar radiation • Uppermost surface seawater and shallow seafloor • Euphotic zone surface to about 100 m (330 ft)

7. Upwelling and nutrient supply • Cooler, deeper seawater nutrient-rich • Areas of coastal upwelling sites of high productivity Fig. 13.6a http://cordellbank.noaa.gov/images/environment/upwelling_470.jpg

8. Light transmission • Visible light of the electromagnetic spectrum • Blue wavelengths penetrate deepest • Longer wavelengths (red, orange) absorbed first Fig. 13.3

9. http://lh4.ggpht.com/_lQw_uDjiHTw/R7AmR74EByI/AAAAAAAAL40/VKg0nZ_Ih6c/DSC_0009.JPGhttp://lh4.ggpht.com/_lQw_uDjiHTw/R7AmR74EByI/AAAAAAAAL40/VKg0nZ_Ih6c/DSC_0009.JPG Light transmission in ocean • Color of ocean ranges from deep blue to yellow-green • Factors • Water depth • Turbidity from runoff • Photosynthetic pigment (chlorophyll) • Eutrophic • Oligotrophic http://upload.wikimedia.org/wikipedia/commons/a/a5/LightningVolt_Deep_Blue_Sea.jpg

10. Light transmission in ocean • SeaStar satellite/SeaWiFS view of ocean chlorophyll and land vegetation (productivity) Fig. 13-5

11. Types of photosynthetic marine organisms • Anthophyta • Seed-bearing plants • Macroscopic (large) algae • Microscopic (small) algae • Photosynthetic bacteria

12. Anthophyta • Only in shallow coastal waters • Primarily seagrasses & • Mangroves http://celebrating200years.noaa.gov/events/sanctuaries/seagrass_meadow650.jpg

13. http://oceanexplorer.noaa.gov/explorations/02sab/logs/aug09/media/lines_600.jpghttp://oceanexplorer.noaa.gov/explorations/02sab/logs/aug09/media/lines_600.jpg Macroscopic algae – “Seaweeds” • Brown algae Sargassum http://www.starfish.ch/photos/plants-Pflanzen/Sargassum.jpg

14. Macroscopic algae – “Seaweeds” • Green algae Caulerpa brachypus, an invasive species in the Indian River Lagoon Codium http://www.sms.si.edu/IRLspec/images/cbrachypus2.jpg http://192.107.66.195/Buoy/System_Description_Codium_Fragile.jpg

15. Macroscopic algae – “Seaweeds” • Red algae • Most abundant and most widespread of “seaweeds” • Varied colors http://www.agen.ufl.edu/~chyn/age2062/lect/lect_15/22_14B.GIF http://www.dnrec.state.de.us/MacroAlgae/information/Indentifying.shtml

16. http://biologi.uio.no/akv/forskning/mbot/images Microscopic algae • Produce food for 99% of marine animals • Most planktonic • Golden algae • Diatoms (tests of silica) • Most abundant single-celled algae – 5600+ spp. • Silicate skeletons – pillbox or rod-shaped ooze • Some w/ sticky threads, spines  slows sinking www.bren.ucsb.edu/ facilities/MEIAF

17. Microscopic algae • Coccolithophores(plates of ate) • Flagellated • calcium carbon plates  possibly sunshades • Coccolithid ooze  fossilized in white cliffs of Dover http://www.esa.int/images http://epod.usra.edu/archive/images/coccolith.jpg

18. Microscopic algae • Dinoflagellates • Mostly autotrophic; some heterotrophic or both • Flagella in grooves for locomotion • Many bioluminescent • Often toxic • Red tides (algal blooms)  fish kills (increase nutrients, runoff) Karenia spp., the alga that causes red tide http://oceanworld.tamu.edu/students/fisheries/images/red_tide_bloom_1.jpg http://www.hku.hk/ecology/porcupine/por24gif/Karenia-digitata.jpg

19. Manatees died in Brevard and Volusia counties in 2007, and on west coast, possibly due to red tide • concentrates on seagrass manatees eat • Breath in toxic fumes http://www.nepa.gov.jm/yourenv/biodiversity/Species/gifs/manatee.jpg

20. http://www.odu.edu/sci/biology/pfiesteria Microscopic algae • Dinoflagellates • Pfiesteria in temperate coastal waters • Ciguatera (from) Gambierdiscustoxicus in tropical fishes • Paralytic, diarhetic, amnesic shellfish poisoning Pfiesteria Gambierdiscus Alexandrium – paralytic shellfish Alexandrium – paralytic shellfish http://www.hrw.com/science/si-science/ biology/plants/algae/ images/Gambitox.jpg http://www.slv2000.qc.ca/bibliotheque/lefleuve/vol11no5/images_f/alexandrium1.jpg

21. Figure 13.D

22. Photosynthetic bacteria • Extremely small • May be responsible for half of total photosynthetic biomass in oceans Anabaena Gleocapsa http://www.micrographia.com/specbiol/bacteri/bacter/bact0200/anabae03.jpg http://silicasecchidisk.conncoll.edu/Pics/Other%20Algae/Blue_Green%20jpegs/Gloeocapsa_Key45.jpg

23. Regional primary productivity • Varies from very low to very high depending on • Distribution of nutrients • Seasonal changes in solar radiation • About 90% of surface biomass decomposed in surface ocean • About 10% sinks to deeper ocean • Only 1% organic matter not decomposed in deep ocean  reaches bottom • Biological pump (CO2 and nutrients to sea floor sediments)

24. Table 13.1

25. Temperate ocean productivity • Seasonal variation with temperature/light/nutrients • Winter: • High winter winds  mixing of sediments/plankton • Low light & few phytoplankton  nutrients increase • Spring: • Phytoplankton blooms with more light, nutrients • Bloom continues until… • Nutrients run out • Herbivores eat enough phytoplankton • Summer: often low production due to lack of nutrients • Fall: Often 2O bloom, as winds bring up nutrients

26. Figure 13.13a

27. Temperate ocean productivity Fig. 13.13

28. Polar ocean productivity • Winter darkness • Summer sunlight • Phytoplankton (diatoms) bloom • Zooplankton (mainly small crustaceans) productivity follows • Example Arctic Ocean Fig. 13.13

29. Polar ocean productivity • Availability of sunlight and • High nutrients due to upwelling of North Atlantic Deep Water • No thermocline • No barrier to vertical mixing • Blue whales migrate to feed on maximum zooplankton productivity

30. Fig. 13-11b

31. Tropical ocean productivity • Permanent thermocline is barrier to vertical mixing • Low rate primary productivity (lack of nutrients) above thermocline

32. http://www-das.uwyo.edu/~geerts/cwx/notes/chap11/equat_upwel.htmlhttp://www-das.uwyo.edu/~geerts/cwx/notes/chap11/equat_upwel.html Tropical ocean productivity • High primary productivity in areas of… • Equatorial upwelling • Coastal upwelling • Coral reefs • Symbiotic algae • Recycle nutrients within theecosystem http://www.igfa.org/images/zooxanthellae.jpg http://static.howstuffworks.com/gif/coral-reef-life.jpg

33. Fig. 13.12

34. Regional productivity summarized Fig. 13.14

35. Energy flow in marine ecosystems • Ecosystem includes living organisms (biotic community) and environment (abiotic factors) • Solar energy converted to chemical energy by producers (mainly photosynthesis)

36. Energy flow in marine ecosystems • Consumers eat other organisms • Herbivores • Carnivores • Omnivores • Bacteriovores • Decomposers breaking down dead organisms or waste products

37. Algae-supported biotic community Fig. 13.15

38. Nutrient flow in marine ecosystems • Nutrients cycled from one chemical form to another • Biogeochemical cycling • Example, nutrients fixed by producers • Passed onto consumers • Some nutrients released to seawater through decomposers • Nutrients can be recycled through upwelling

39. Biogeo-chemical cycling Fig. 13.16

40. Feeding strategies • Suspension feeding or filter feeding • Take in seawater and filter out usable organic matter • Deposit feeding • Take in detritus and sediment and extract usable organic matter • Carnivorous feeding • Organisms capture and eat other animals

41. Feeding strategies Fig. 13.17d

42. Trophic levels • Feeding stage is trophic level • Chemical energy is transferred from producers to consumers • On average, about 10% of energy is transferred to next trophic level Fig. 13-18

43. Passage of energy between trophic levels Fig. 13.19

44. Food chain Food web • Branching network of many consumers • Consumers more likely to survive with alternative food sources • Primary producer • Herbivore • One or more carnivores

45. Foodwebs are more complex & more realistic • Consumers often operate at two or more levels http://users.aber.ac.uk/pmm1

46. http://www-sci.pac.dfo-mpo.gc.ca/mehsd/images/ross_photos

47. Biomass pyramid • Both number of individuals and total biomass (weight) decrease at successive trophic levels • Organisms increase in size Fig. 13.21

48. Symbiosis • Organisms associate in beneficial relationship • Commensalism • One benefits without harm to other • Mutualism • Mutually beneficial • Parasitism • One benefits and may harm the other

49. Marine fisheries • Commercial fishing • Most tonnage from continental shelves and coastal fisheries, compared to open ocean fisheries • Over 20% of catch from areas of upwelling that make up 0.1% of ocean surface area Fig. 13.23

50. http://www.fao.org/docrep/009/y5852e/Y5852E12.jpg Overfishing Figure A2.4 - Stage of development of the 200 major marine fishery resources: 1950–2000 • Taking more fish than is sustainable over long periods • Remaining fish younger, smaller • About 30% of fish stocks depleted or overfished • About 47% fished at biological limit State of exploitation of selected stock or species groups for which assesment information is available, by major marine fishing areas, 2004 http://www.fao.org/docrep/009/y5852e/Y5852E08.jpg