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|last2=Christensen|first2=L.B.
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|title=The Impact of Whaling on the Ocean Carbon Cycle: Why Bigger Was Better
|title=The Impact of Whaling on the Ocean Carbon Cycle: Why Bigger Was Better
|journal=PLoS ONE
|journal=PLoS ONE
|volume=5
|volume=5
|pages=e12444
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|doi=10.1371/journal.pone.0012444}} (Table 1)</ref>
|doi=10.1371/journal.pone.0012444
|postscript=<!-- Bot inserted parameter. Either remove it; or change its value to "." for the cite to end in a ".", as necessary. -->[[Category:Articles with inconsistent citation formats]]}} (Table 1)</ref>
|Pre-whaling
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|40%<ref name="WhaleCarbon">{{Citation
|40%<ref name="WhaleCarbon">{{Cite journal
|last1=Jelmert|first1=A.
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|last2=Oppen-Berntsen|first2=D.O.
|last2=Oppen-Berntsen|first2=D.O.
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|year=1996
|year=1996
|volume=10
|volume=10
|pages=653-654
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|doi=10.1046/j.1523-1739.1996.10020653.x
|doi=10.1046/j.1523-1739.1996.10020653.x
|postscript=<!-- Bot inserted parameter. Either remove it; or change its value to "." for the cite to end in a ".", as necessary. -->[[Category:Articles with inconsistent citation formats]]
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|4.69 x 10<sup>35</sup>{{#tag:ref|Assuming half the dry biomass is protein and half fat, with respective carbon contents of 54% and 77%<ref name="WhaleCarbon" />, hence 35.7 x (0.2 x 0.54 + 0.2 x 0.77) = 9.35 Mt carbon, or 9.35e12 / 12.011 * 6.0221415e23 atoms}}
|4.69 x 10<sup>35</sup>{{#tag:ref|Assuming half the dry biomass is protein and half fat, with respective carbon contents of 54% and 77%<ref name="WhaleCarbon" />, hence 35.7 x (0.2 x 0.54 + 0.2 x 0.77) = 9.35 Mt carbon, or 9.35e12 / 12.011 * 6.0221415e23 atoms}}
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Humans comprise about 100 million tonnes of the Earth's biomass<ref>The world [[human population]] was 6.6 billion in January 2008. At an average weight of 100 pounds (30 lbs of biomass), that equals 100 million tonnes.</ref>, [[domesticate]]d animals about 700 million tonnes, and [[agriculture|crops]] about 2 billion tonnes. {{Citation needed|date=March 2007}} The total biomass of bacteria is estimated to equal that of plants.<ref name="Whitman etal">Whitman, Coleman, and Wiebe, [http://www.pnas.org/cgi/reprint/95/12/6578.pdf Prokaryotes: The unseen majority], Proc. Natl. Acad. Sci. USA, Vol. 95, pp. 6578–6583, June 1998</ref>
Humans comprise about 100 million tonnes of the Earth's biomass<ref>The world [[human population]] was 6.6 billion in January 2008. At an average weight of 100 pounds (30 lbs of biomass), that equals 100 million tonnes.</ref>, [[domesticate]]d animals about 700 million tonnes, and [[agriculture|crops]] about 2 billion tonnes. {{Citation needed|date=March 2007}} The total biomass of bacteria is estimated to equal that of plants.<ref name="Whitman etal">Whitman, Coleman, and Wiebe, [http://www.pnas.org/cgi/reprint/95/12/6578.pdf Prokaryotes: The unseen majority], Proc. Natl. Acad. Sci. USA, Vol. 95, pp. 6578–6583, June 1998</ref>
The most successful [[animal]] species, in terms of biomass, is probably [[Antarctic krill]], ''Euphausia superba'', with a fresh biomass somewhat under 500 million [[tonne]]s.<ref name="NE97"/><ref>Ross, R. M. and Quetin, L. B. (1988). Euphausia superba: a critical review of annual production. Comp. Biochem. Physiol. 90B, 499-505.</ref><ref name="KrillBiomass2009">{{Citation
The most successful [[animal]] species, in terms of biomass, is probably [[Antarctic krill]], ''Euphausia superba'', with a fresh biomass somewhat under 500 million [[tonne]]s.<ref name="NE97"/><ref>Ross, R. M. and Quetin, L. B. (1988). Euphausia superba: a critical review of annual production. Comp. Biochem. Physiol. 90B, 499-505.</ref><ref name="KrillBiomass2009">{{Cite journal
|doi=10.1016/j.dsr.2008.12.007
|last1=Atkinson|first1=A.
|last1=Atkinson|first1=A.
|last2=Siegel|first2=V.
|last2=Siegel|first2=V.
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|volume=56
|volume=56
|pages=727–740
|pages=727–740
|url=http://www.iced.ac.uk/documents/Atkinson%20et%20al,%20Deep%20Sea%20Research%20I,%202009.pdf}}</ref> However, as a group, the small aquatic [[crustacean]]s called [[copepod]]s may form the largest animal biomass on earth.<ref name=Ossietzky>[http://www.uni-oldenburg.de/zoomorphology/Biology.html Biology of Copepods] at [[Carl von Ossietzky University of Oldenburg]]</ref> A 2009 paper in ''Science'' estimates, for the first time, the total world fish biomass as somewhere between 0.8 and 2.0 billion tonnes.<ref>Wilson RW, Millero FJ, Taylor JR, Walsh PJ, Christensen V, Jennings S, Grosell M (2009) [http://www.sciencemag.org/cgi/content/abstract/323/5912/359 "Contribution of Fish to the Marine Inorganic Carbon Cycle"] ''Science'', '''323''' (5912) 359-362.</ref><ref>[http://www.physorg.com/news151251277.html Researcher gives first-ever estimate of worldwide fish biomass and impact on climate change] ''[[PhysOrg.com]]'', 15 January 2009.</ref>
|url=http://www.iced.ac.uk/documents/Atkinson%20et%20al,%20Deep%20Sea%20Research%20I,%202009.pdf
|postscript=<!-- Bot inserted parameter. Either remove it; or change its value to "." for the cite to end in a ".", as necessary. -->[[Category:Articles with inconsistent citation formats]]}}</ref> However, as a group, the small aquatic [[crustacean]]s called [[copepod]]s may form the largest animal biomass on earth.<ref name=Ossietzky>[http://www.uni-oldenburg.de/zoomorphology/Biology.html Biology of Copepods] at [[Carl von Ossietzky University of Oldenburg]]</ref> A 2009 paper in ''Science'' estimates, for the first time, the total world fish biomass as somewhere between 0.8 and 2.0 billion tonnes.<ref>Wilson RW, Millero FJ, Taylor JR, Walsh PJ, Christensen V, Jennings S, Grosell M (2009) [http://www.sciencemag.org/cgi/content/abstract/323/5912/359 "Contribution of Fish to the Marine Inorganic Carbon Cycle"] ''Science'', '''323''' (5912) 359-362.</ref><ref>[http://www.physorg.com/news151251277.html Researcher gives first-ever estimate of worldwide fish biomass and impact on climate change] ''[[PhysOrg.com]]'', 15 January 2009.</ref>


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Revision as of 01:13, 19 September 2010

For biomass as a renewable energy source, see biomass
The total global live biomass has been estimated as 2000 billion tonnes of which 1600 billion tonnes are found in forests.[1][2]
However shallow aquatic environments, such as wetlands, estuaries and coral reefs, are as productive as forests, generating similar amounts of new biomass each year on a given area.[3]

Biomass, in ecology, is the mass of living biological organisms in a given area or ecosystem at a given time. Biomass can refer to species biomass, which is the mass of one or more species, or to community biomass, which is the mass of all species in the community. It can include microorganisms, plants or animals.[4] The mass can be expressed as the average mass per unit area, or as the total mass in the community.

How biomass is measured depends on why it is being measured. Sometimes the biomass is regarded as the natural mass of organisms in situ, just as they are. For example, in a salmon fishery, the salmon biomass might be regarded as the total wet weight the salmon would have if they were taken out of the water. In other contexts, biomass can be measured in terms of the dried organic mass, so perhaps only 30% of the actual weight might count, the rest being water. For other purposes, only biological tissues count, and teeth, bones and shells are excluded.

In stricter scientific applications, biomass is measured as the mass of organically bound carbon (C) that is present. The total annual primary production of biomass for the Earth is just over 100 billion tonnes C/yr.[5]

Ecological pyramids

An ecological pyramid.
Main article: Ecological pyramid

An ecological pyramid is a graphical representation which shows, for a given ecosystem, the relationship between biomass or biological productivity and trophic levels.

  • A biomass pyramid shows the amount of biomass at each trophic level.
  • A productivity pyramid shows the production or turn-over in biomass at each trophic level.

An ecological pyramid provides a snapshot in time of an ecological community.

The bottom of the pyramid represents the primary producers (autotrophs). The primary producers take energy from the environment in the form of sunlight or inorganic chemicals and use it to create energy-rich molecules such as carbohydrates. This mechanism is called primary production. The pyramid then proceeds through the various trophic levels to the apex predators at the top.

When energy is transferred from one trophic level to the next, typically only ten percent is used to build new biomass. The remaining ninety percent goes to metabolic processes or is dissipated as heat. This energy loss means that productivity pyramids are never inverted, and generally limits food chains to about six levels. However, in oceans, biomass pyramids can be wholly or partially inverted, with more biomass at higher levels.

Terrestrial biomass

Terrestrial biomass generally decreases markedly at each higher trophic level (plants, herbivores, carnivores). Examples of terrestrial producers are grasses, trees and shrubs. These have a much higher biomass than the animals that consume them, such as deer, zebras and insects. The level with the least biomass are the highest predators in the food chain, such as foxes and eagles.

In a temperate grassland, grasses and other plants are the primary producers at the bottom of the pyramid. Then come the primary consumers, grasshoppers, voles and bison, followed by the secondary consumers, shrews, hawks and small cats, and finally the tertiary consumers, large cats and wolves. The biomass pyramid is not inverted, and decreases markedly at each higher level.

Ocean biomass

marine food chain
(typical)
  Sun
↓
phytoplankton
↓
herbivorous zooplankton
↓
carnivorous zooplankton
↓
  filter feeder
↓
  predatory vertebrate

Ocean biomass, in a reversal of terrestrial biomass, can increase at higher trophic levels. In the ocean, the food chain typically starts with phytoplankton, and follows the course:

Phytoplankton → zooplankton → predatory zooplankton → filter feeders → predatory fish

Phytoplankton are the main primary producers at the bottom of the marine food chain. Phytoplankton use photosynthesis to convert inorganic carbon into protoplasm. They are then consumed by microscopic animals called zooplankton.

Zooplankton comprise the second level in the food chain, and include the larva of fish, squid, lobsters and crabs, small crustaceans such as copepods and krill, and many other types.

In turn, smaller zooplankton are consumed both by larger predatory zooplankters, such as krill, and by forage fish, which are small schooling filter feeding fish. This makes up the third level in the food chain.

An ocean food web showing a network of food chains

The fourth trophic level consists of predatory fish, marine mammals, and seabirds which consume forage fish. Examples are swordfish, seals and gannets.

Apex predators, such as orcas which can consume seals and shortfin mako sharks which can consume swordfish, make up the fifth trophic level. Baleen whales can consume zooplankton and krill directly, leading to a food chain with only three or four trophic levels.

Marine environments can have inverted biomass pyramids. In particular, the biomass of consumers (copepods, krill, shrimp, forage fish) is larger than the biomass of primary producers. This happens because the ocean primary producers are tiny phytoplankton which grow and reproduce rapidly, so a small mass can have a fast rate of primary production. In contrast, terrestrial primary producers are plants which grow and reproduce slowly.

Global biomass

Species Date for estimate individual count average living weight of individual in kg percent biomass (dried) total number of carbon atoms global dry biomass in million tonnes global wet (fresh) biomass in million tonnes
Antarctic krill 1924-2004 7.8 x 1014 0.486 g 379[6]
Humans 2008[7] 6.7 billion 50 kg 30% 6.7 x 109 x 5x1026 [8] 100 335
Copepod (Plankton) 10-6 - 10−9 kg
Cattle 1.3 billion 400 kg 30% 156 ?520
Sheep and Goats 2002 1.75 billion [9] 60 kg 30% 31.5
Blue whales[10] Pre-whaling 340280 40%[11] 4.69 x 1035[12] 35.7
Blue whales[10] 2001 4727 40%[11] 0.5
Chickens 24 billion 2 kg 30% 14.4
Ants 107 - 108 billion [13] 3 x 10−4kg
(0.3 grams) 		30% 900-9,000
Marine fish 800-2,000[14]

Humans comprise about 100 million tonnes of the Earth's biomass[15], domesticated animals about 700 million tonnes, and crops about 2 billion tonnes. [citation needed] The total biomass of bacteria is estimated to equal that of plants.[16] The most successful animal species, in terms of biomass, is probably Antarctic krill, Euphausia superba, with a fresh biomass somewhat under 500 million tonnes.[17][18][6] However, as a group, the small aquatic crustaceans called copepods may form the largest animal biomass on earth.[19] A 2009 paper in Science estimates, for the first time, the total world fish biomass as somewhere between 0.8 and 2.0 billion tonnes.[20][21]

  • Grasses, trees and shrubs have a much higher biomass than the animals that consume them
    Grasses, trees and shrubs have a much higher biomass than the animals that consume them
  • The total biomass of bacteria may equal that of plants.[16]
    The total biomass of bacteria may equal that of plants.[16]
  • Copepods may form the largest biomass of any animal species group.[19]
    Copepods may form the largest biomass of any animal species group.[19]
  • Antarctic krill form one of the largest biomasses of any individual animal species.[17]
    Antarctic krill form one of the largest biomasses of any individual animal species.[17]

The total global biomass has been estimated to be 2000 billion tonnes with 1600 billion of those tonnes in forests.[22][23]

Global rate of production

Globally, terrestrial and oceanic habitats produce a similar amount of new biomass each year (56.4 billion tonnes C terrestrial and 48.5 billion tonnes C oceanic).

Net primary production is the rate at which new biomass is generated, mainly due to photosynthesis. Global primary production can be estimated from satellite observations. Satellites scan the normalised difference vegetation index (NDVI) over terrestrial habitats, and scan sea-surface chlorophyll levels over oceans. This results in 56.4 billion tonnes C/yr (53.8%), for terrestrial primary production, and 48.5 billion tonnes C/yr for oceanic primary production.[5] Thus, the total photoautotrophic primary production for the Earth is about 104.9 billion tonnes C/yr. This translates to about 426 gC/m²/yr for land production (excluding areas with permanent ice cover), and 140 gC/m²/yr for the oceans.

However, there is a much more significant difference in standing stocks—while accounting for almost half of total annual production, oceanic autotrophs account for only about 0.2% of the total biomass. Autotrophs may have the highest global proportion of biomass, but they are closely rivaled or surpassed by microbes.[24][25]

Some global producers of biomass in order of productivity rates are

Producer Biomass productivity
(gC/m²/yr) 		Ref Total area
(million km²) 		Ref Total production
(billion tonnes C/yr)
swamps and marshes 2,500 [3]
tropical rain forests 2,000 [26] 8 16
coral reefs 2,000 [3] 0.28 [27] 0.56
algal beds 2,000 [3]
river estuaries 1,800 [3]
temperate forests 1,250 [3] 19 24
cultivated lands 650 [3][28] 17 11
tundras 140 [3][28]
open ocean 125 [3][28] 311 39
deserts 3 [28] 50 0.15

See also

Notes

  1. ^ "Biomass Basic Information".
  2. ^ "Biomass".
  3. ^ a b c d e f g h i Ricklefs, Robert E.; Miller, Gary Leon (2,000). Ecology (4th ed.). Macmillan. p. 192. ISBN 9780716728290. {{cite book}}: Check date values in: |year= (help)
  4. ^ IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "biomass". doi:10.1351/goldbook.
  5. ^ a b Field, C.B. (1998). "Primary production of the Biosphere: Integrating Terrestrial and Oceanic Components". Science. 281: 237–240. doi:10.1126/science.281.5374.237. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  6. ^ a b Atkinson, A.; Siegel, V.; Pakhomov, E.A.; Jessopp, M.J.; Loeb, V. (2009). "A re-appraisal of the total biomass and annual production of Antarctic krill" (PDF). Deep-Sea Research I. 56: 727–740. doi:10.1016/j.dsr.2008.12.007{{cite journal}}: CS1 maint: postscript (link)
  7. ^ US world population clock
  8. ^ Freitas, Robert A. Jr.Nanomedicine 3.1 Human Body Chemical Composition Foresight Institute, 1998
  9. ^ World's Rangelands Deteriorating Under Mounting Pressure Earth Policy Institute 2002
  10. ^ a b Pershing, A.J.; Christensen, L.B.; Record, N.R.; Sherwood, G.D.; Stetson, P.B.; Humphries, Stuart (2010). "The Impact of Whaling on the Ocean Carbon Cycle: Why Bigger Was Better". PLoS ONE. 5: e12444. doi:10.1371/journal.pone.0012444{{cite journal}}: CS1 maint: postscript (link) CS1 maint: unflagged free DOI (link) (Table 1)
  11. ^ a b c Jelmert, A.; Oppen-Berntsen, D.O. (1996). "Whaling and Deep-Sea Biodiversity". Conservation Biology. 10: 653–654. doi:10.1046/j.1523-1739.1996.10020653.x{{cite journal}}: CS1 maint: postscript (link)
  12. ^ Assuming half the dry biomass is protein and half fat, with respective carbon contents of 54% and 77%[11], hence 35.7 x (0.2 x 0.54 + 0.2 x 0.77) = 9.35 Mt carbon, or 9.35e12 / 12.011 * 6.0221415e23 atoms
  13. ^ Embery, Joan; Lucaire, Ed Collection of Amazing Animal Facts. 1983.
  14. ^ Wilson RW, Millero FJ, Taylor JR, Walsh PJ, Christensen V, Jennings S and Grosell M (2009) "Contribution of Fish to the Marine Inorganic Carbon Cycle" Science, 323 (5912) 359-362. (This article provides a first estimate of global fish biomass)
  15. ^ The world human population was 6.6 billion in January 2008. At an average weight of 100 pounds (30 lbs of biomass), that equals 100 million tonnes.
  16. ^ a b Whitman, Coleman, and Wiebe, Prokaryotes: The unseen majority, Proc. Natl. Acad. Sci. USA, Vol. 95, pp. 6578–6583, June 1998
  17. ^ a b Nicol, S., Endo, Y. (1997). Fisheries Technical Paper 367: Krill Fisheries of the World. FAO.{{cite book}}: CS1 maint: multiple names: authors list (link)
  18. ^ Ross, R. M. and Quetin, L. B. (1988). Euphausia superba: a critical review of annual production. Comp. Biochem. Physiol. 90B, 499-505.
  19. ^ a b Biology of Copepods at Carl von Ossietzky University of Oldenburg
  20. ^ Wilson RW, Millero FJ, Taylor JR, Walsh PJ, Christensen V, Jennings S, Grosell M (2009) "Contribution of Fish to the Marine Inorganic Carbon Cycle" Science, 323 (5912) 359-362.
  21. ^ Researcher gives first-ever estimate of worldwide fish biomass and impact on climate change PhysOrg.com, 15 January 2009.
  22. ^ "Biomass Basic Information".
  23. ^ "Biomass".
  24. ^ Whitman, W. B.; Coleman, D. C.; Wieb, W. J. (1998). "Prokaryotes: The unseen majority" (PDF). Proc. Natl. Acad. Sci. USA. 95 (12): 6578–6583. doi:10.1073/pnas.95.12.6578. PMC 33863. PMID 9618454.
  25. ^ Groombridge, B.; Jenkins, M. (2002). World atlas of biodiversity: earth's living resources in the 21st century. World Conservation Monitoring Centre, United Nations Environment Programme. ISBN 0-520-23688-8. {{cite book}}: Check |isbn= value: checksum (help)
  26. ^ Ricklefs, Robert E.; Miller, Gary Leon (2000). Ecology (4th ed.). Macmillan. p. 197. ISBN 9780716728290.
  27. ^ Spalding, Mark, Corinna Ravilious, and Edmund Green. 2001. World Atlas of Coral Reefs. Berkeley, CA: University of California Press and UNEP/WCMC.
  28. ^ a b c d Park, Chris C. (2001). The environment: principles and applications (2nd ed.). Routledge. p. 564. ISBN 9780415217705.

References

External links

Look up biomass in Wiktionary, the free dictionary.
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