::Biomass (ecology)


Center::first    Biomass::journal    Title::primary    Align::billion    Tonnes::total    Global::issue

{{ safesubst:#invoke:Unsubst||$N=Use dmy dates |date=__DATE__ |$B= }} {{#invoke:Multiple image|render}}

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.<ref>IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version:  (2006–) "biomass".</ref> 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{{ safesubst:#invoke:Unsubst||date=__DATE__ |$B= }} scientific applications, biomass is measured as the mass of organically bound carbon (C) that is present.

Apart from bacteria, the total live biomass on Earth is about 560 billion tonnes C,<ref name=Groombridge/> and the total annual primary production of biomass is just over 100 billion tonnes C/yr.<ref name=Behrenfeld /> However, the total live biomass of bacteria may exceed that of plants and animals.<ref name=EoE/><ref name=gould/> The total amount of DNA base pairs on Earth, as a possible approximation of global biodiversity, is estimated at 5.0 x 1037, and weighs 50 billion tonnes.<ref name="NYT-20150718-rn">{{#invoke:citation/CS1|citation |CitationClass=news }}</ref> In comparison, the total mass of the biosphere has been estimated to be as much as 4 TtC (trillion tons of carbon).<ref name="AGCI-2015">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Biomass (ecology) sections
Intro  Ecological pyramids  Terrestrial biomass  Ocean biomass  Bacterial biomass  Global biomass  Global rate of production  See also  References  Further reading  External links  

PREVIOUS: IntroNEXT: Ecological pyramids