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The gain of a biomass in the ecosystem, created for a time unit, is called biological production (efficiency). There are primary and secondary productions of community.
Primary production is a biomass created by producers for a time unit. It is divided into total and pure productions. Total primary production (the general assimilation) is the general biomass created by plants during photosynthesis. Its part is discharged for maintenance of ability to live of plants (expenses for breath (40-70 %). The remained part makes up pure primary production (pure assimilation) which in the further is used by consumers and reducers, or it is collected in the ecosystem.
Secondary production is a biomass created by consumers for a time unit. It is various for each following trophic level.
The weight of organisms of the certain group (producers, consumers, reducers) or communities as a whole is called a biomass. Tropical rain woods posses the highest biomass and efficiency, and the lowest is desert and tundra (tab. 8).
If velocity of the plants growth (formation of the primary production) in the ecosystem is above rates of its processing by consumers and reducers it results in increase of producer biomass. If recycling of products decomposition in chain of decomposition is insufficient an accumulation of dead organic substance proceeds. It results in peatining bogs, in formation of a powerful wood laying, etc. In stable ecosystems the biomass remains constant as practically all production is spent in the food chains.
Biocenosis, biotope and biogeocenosis. A group of organisms in a self-sufficient community naturally occupying a small area with a uniform environment throughout. In the field of paleontology, it is one of three types of fossil communities, which depends on the condition and completeness of the community when found. Biocenosis is the most complete type, able to offer the most information about what the community was like when it was alive.
(biocoenose, biocenose, biotic community, biological community, ecological community), coined by Karl Möbius in 1877, describes the interacting organisms living together in a habitat. This term is rarely used in English, as this concept has not been popularized in Anglophone countries. Instead, English-speaking scientists normally use the terms ecosystems or communities.
Descriptors in an ecosystem are:
· Zoocoenosis for the faunal community,
· Phytocoenosis for the floral community,
· Microbiocoenosis for the microbial community.
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