Primary production is a certain amount in ecology. The method for measuring it was invented by the Soviet hydrobiologist Georgy Georgievich Vinberg in the first half of the 20th century. The first experiment was carried out near Moscow.
The concept
In his concept, A. N. Leontyev introduces the term "primary production". It denotes a certain value in ecology, which determines the increase in the amount of organic matter formed in a certain time by autotrophic organisms from simple inorganic components. The calculation of primary production takes place over a specified period of time, the length of which is determined by biologists.
Autotrophic organisms
These are organisms that are able to use inorganic substances to produce organic. Autotrophs are on the first tier of the food pyramid, as they are the primary producers of organic matter in the biosphere. Thanks to these organisms, heterotrophs (those organisms that cannot receive organic elements from inorganic ones through photosynthesis or chemosynthesis) are provided with food.
There are organisms that belong simultaneously to two species: green euglena algae at night refers to heterotrophs, and during the day - to autotrophs. Such organisms are called mixotrophs.
How is this value estimated?
To calculate this value, one should measure the amount of carbon, which for a certain time has been bound by plants growing on the earth, and phytoplankton living in the ocean. All this is calculated per unit area.
Sometimes, as in the case of phytoplankton, primary production is evaluated within small time intervals, most often it is a day. This is because this organism has a high rate of formation of organic matter, which is calculated based on a unit of biomass (a set of plants and animals that are part of a biogeocenosis of any size and level).
If we consider the time during which the primary production of terrestrial plants is measured, then it will be one year or the growing season (the period in a year during which certain living plant organisms are subject to development). This duration of the assessment is explained by the fact that the rate of conversion of inorganic substances to organic in this species of organisms is much slower than in plankton.
For whom does the concept of primary production apply?
This value is calculated for photoautotrophic and chemoautotrophic organisms. For the former, sunlight is the source of energy, while the latter produce organic matter from inorganic substances through redox reactions with simple substances that they themselves create. Few organisms are capable of the second method of energy production, these include bacteria, some prokaryotes (unicellular, which have a nucleus and membranes in the cell).
In the modern world, the role of chemoautotrophs is small. They are of greatest importance in hydrothermal ecosystems (oases of life that are located at a considerable depth in the ocean, where there are crustal cracks with hot water coming out of them, rich in reduced compounds), although primary production there is not evaluated in very large quantities, but the importance its great.
Gross value
Researchers divide the primary production of ecosystems into gross and clean.
The first term denotes the value of the total aggregate of organic substances produced by the producer.
The net primary value includes the obtained organic substances, taking into account the deduction of the costs that the producer body requires to perform respiratory activity. It is this type of quantity that is the substance that consumers can use for their needs, in other words, pure primary production is the basis for supporting the trophic chain (a number of relationships between different organisms, with the help of which the transfer of various types of energy and matter by eating certain individuals others).
Research
Initially, G.G. Vinberg accounted for primary production on the lake using the "dark and light phial" method. It consisted in comparing the amount of organic matter obtained and oxygen released during photosynthesis. Later, the researchers found that this method of assessing primary production is unreliable, since it has a reduced sensitivity. Therefore, the biologist E. Stemann-Nielsen proposed an alternative "radiocarbon method." In this method, carbon dioxide and a radioactive carbon isotope were added to water samples containing plankton. Later, the amount of organic matter was calculated based on the associated radioactive carbon.
Research in this area, since the 60s of the XX century, has been carried out around the world, and they have not stopped until now, delighting scientists with new discoveries.