Biomass is the mass of biological organisms that live in a particular area or ecosystem at any given time. Biomass can refer to species biomass , which is the mass of one or more species, or community biomass , which is the mass of all species in society. This may include microorganisms, plants or animals. The mass can be expressed as the average mass per unit area, or as a total mass in society.
How biomass is measured depends on why it is measured. Sometimes, biomass is considered a natural mass of in situ organisms, just like they are. For example, in salmon fisheries, salmon biomass may be considered the total wet weight that salmon will have if they are removed from the water. In other contexts, biomass can be measured in the form of dry organic mass, so perhaps only 30% of the actual weight may be calculated, the remainder being water. For other purposes, count only biological tissues, and teeth, bones and shells are excluded. In some applications, biomass is measured as an organically bound (C) carbon mass present.
The total life biomass on Earth is about 550-560 billion tonnes C, and the total annual biomass production is just over 100 billion ton C/year. The total biomass of bacteria may be as much as there are in plants and animals or maybe much less. The total number of DNA base pairs on Earth, as a possible estimate of global biodiversity, is estimated at 5.0 x 10 37 , and weighs 50 billion tons. For comparison, the total mass of the biosphere has been estimated as much as 4 x 10 12 tons of carbon.
Video Biomass (ecology)
Piramida ekologi
The ecological pyramid is a graphical representation that shows, for certain ecosystems, the relationship between biomass or biological productivity and trophic levels.
- A biomass pyramid shows the amount of biomass at each trophic level.
- Productivity pyramid shows the production or replacement of biomass at each trophic level.
The ecological pyramid provides snapshots in ecological community time.
The bottom of the pyramid represents the main producer (autotrof). The major producers take energy from the environment in the form of sunlight or inorganic chemicals and use them to create energy-rich molecules such as carbohydrates. This mechanism is called primary production. The pyramid then continues through various trophic levels to the top predator at the top.
When energy is transferred from one trophic level to the next, usually only ten percent is used to build new biomass. The remaining ninety percent goes to the metabolic process or is disposed of as heat. This loss of energy means that the productivity pyramid never reverses, and generally restricts the food chain to about six levels. However, in the oceans, biomass pyramids can be completely or partially reversed, with more biomass at higher levels.
Maps Biomass (ecology)
Terrestrial biomass
Terrestrial biomass generally declines significantly at any higher trophic level (plant, herbivore, carnivorous). Examples of terrestrial producers are grass, trees, and bushes. It has a much higher biomass than the animals that eat it, such as deer, zebra and insects. Levels with the smallest biomass are the highest predators in the food chain, such as foxes and eagles.
In medium grasslands, grasses and other plants are major producers at the bottom of the pyramid. Then comes the main consumers, such as grasshoppers, rats and bison, followed by secondary consumers, shrew, eagles and small cats. Finally tertiary consumers, big cats and wolves. The biomass pyramid drops sharply at any higher level.
Marine biomass
Marine or marine biota, in the reversal of terrestrial biomass, may increase at higher trophic levels. In the ocean, the food chain usually starts with phytoplankton, and follows the course:
Phytoplankton -> zooplankton -> zooplankton predator -> pengumpan filter -> ikan predator
Phytoplankton is a major major producer at the bottom of the seafood chain. Phytoplankton use photosynthesis to convert inorganic carbon into protoplasm. They are then consumed by microscopic animals called zooplankton.
Zooplankton consists of the second level in the food chain, and includes small crustaceans, such as copepods and krill, and fish, squid, lobster and crab larvae.
In turn, small zooplankton are consumed by larger predator zooplankters, such as krill, and by forage fish, which are small, go to school, feed the fish. This is the third level in the food chain.
The fourth trophic level consists of predatory fish, marine mammals and seabirds that consume forage fish. Examples are swordfish, seals and gannets.
Top predators, such as orcas, which can consume seals, and short-bladed sharks, can consume swordfish, into the fifth trophic level. Baleen whales can consume zooplankton and krill directly, leading to a food chain with only three or four trophic levels.
The marine environment can have an inverted biomass pyramid. In particular, consumer biomass (copepods, krill, shrimp, forage) is larger than primary producer biomass. This is because the main producers of the oceans are small phytoplankton that grow and multiply rapidly, so that small masses can have a fast primary rate of production. Instead, terrestrial primary producers grow and reproduce slowly.
There are exceptions with cyanobacteria. Marine cyanobacteria are the smallest known organisms of photosynthesis; the smallest, Prochlorococcus , is only 0.5-0.8 micrometers. Prochlorococcus is probably the most abundant species on Earth: a milliliter of surface sea water may contain 100,000 cells or more. Around the world, it is estimated that there are some individual October (~ 10 27 ). Prochlorococcus is ubiquitous between 40Ã, Â ° N and 40Ã, Â ° S and dominates oligotrophic (malnourished) oceans. Bacterial accounts for about 20% oxygen in Earth's atmosphere, and are part of the bottom of the seafood chain.
Bacterial biomass
Usually there are 50 million bacterial cells in one gram of soil and one million bacterial cells in fresh water mililiter. Census 2018 provides bacterial biomass? 70 billion tonnes of carbon, equal to 15% of all biomass, In a much cited study from 1998, the world's bacterial biomass has been erroneously calculated to be 350 to 550 billion tonnes of carbon, equal to between 60% and 100% carbon in plants. A more recent study of marine underlying microbes has created considerable doubt on this, a study in 2012 reducing the microbial biomass calculated on the seafloor from 303 billion ton C to just 4.1 billion tonnes C, reducing the prokaryotes' global biomass to 50 to 250 billion tons C. Furthermore, if the average biomass per prokaryote cell decreases from 86 to 14 femtogram C then prokaryotes global biomass decreases to 13 to 44.5 billion tonnes C, equal to between 2.4% and 8.1% of carbon in plants. The current value (70 billion tons of carbon) was issued in May 2018.
Global biomass
Estimates for global biomass of species and higher-level groups are not always consistent across the literature. In addition to bacteria, total global biomass has been estimated at about 560 billion tonnes C. Most of this biomass is found on land, with only 5 to 10 billion tonnes of C being found in the oceans. On land, there are about 1,000 times more plant biomass ( phytomass ) than animal biomass ( zoomass ). About 18% of the biomass of this plant is eaten by terrestrial animals. However, in the oceans, animal biomass is almost 30 times larger than plant biomass. Most marine plant biomass is eaten by marine animals.
Humans comprise about 100 million tons of Earth's dry biomass, about 700 million tons of pets, earthworms over 1,100 million tons, and an annual cereal plant of about 2.3 billion tons.
The most successful animal species, in terms of biomass, may be Antarctic krill, Euphausia superba , with fresh biomass approaching 500 million tonnes, although domestic livestock can also reach this enormous number. However, as a group, small water crustaceans called copepods can form the largest animal biomass on earth. A 2009 paper in Science estimates, for the first time, total world fish biomass as somewhere between 0.8 and 2.0 billion tons. It is estimated that about 1% of global biomass is due to phytoplankton, and 25% is caused by fungi.
Global production level
Primary net production is the rate at which new biomass is produced, primarily due to photosynthesis. Global primary production can be estimated from satellite observations. Satellites scan the normal difference vegetation index (NDVI) above terrestrial habitat, and scan the level of sea level chlorophyll over the ocean. This yielded 56.4 billion tonnes of C/yr (53.8%), for terrestrial primary production, and 48.5 billion tonnes C/yr for primary ocean production. Thus, the total photoautotropic main production for the Earth is about 104.9 billion tonnes C/year. This means about 426 gC/mÃ,²/year for land production (excluding areas with permanent ice sheets), and 140 gC/mÃ,²/yr for oceans.
However, there is a much more significant difference in standing stocks - while accounting for almost half of the total annual production, the marine autotroph is only about 0.2% of the total biomass. Autotrophs may have the highest proportion of global biomass, but they are greatly rivaled or surpassed by microbes.
Freshwater ecosystems generate about 1.5% of global net primary production.
Some global producers of biomass in terms of productivity levels
See also
- Biomass (as in bioproducts)
- Natural organic ingredients
- Productivity (ecology)
- Primary nutrition group
- Existing stock
- Lake Pohjalampi - biomass manipulation study
- List of water animals harvested by weight
References
Further reading
- Foley, JA; Monfreda, C; Ramankutty, N and Zaks, D (2007) Our section of the planetary pie Proceedings of the National Academy of Sciences USA, 104 (31): 12585-12586. Download
- Haberl, H; Erb, KH; Krausmann, F; Gaube, V; Bondeau, A; Plutzar, C; Gingrich, S; Lucht, W and Fischer-Kowalski, M (2007) Measuring and mapping human appropriation of net primary production in the earth's ecosystem Proceedings of the National Academy of Sciences of the USA, 104 (31): 12942 -12947. Download
- Purves, William K and Orians, Gordon H (2007) Life: The Science of Biology, 8th Ed. W. H. Freeman. ISBN: 978-1-4292-0877-2
External links
- The mass of all life on Earth is astonishing - until you consider how much has been lost
- Counting the bacteria
- Trophic level
- Distribution of biomass to high trophic level fish in the North Atlantic, 1900-2000
Source of the article : Wikipedia
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