Ecological Niche

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Ecological Niche

 

the role of a species (more precisely, its population) in a biological community (biocenosis). The interaction of a given species (population) with other members of the community establishes its role in the cycle of matter, determined by food and competition ties in the biocenosis.

The term “ecological niche” was proposed by the American scientist J. Grinnell (1917). The interpretation of the ecological niche as the position of a species in the food chain of one or several biocenoses was proposed by the British ecologist C. Elton (1927). Such an interpretation makes it possible to assign a quantitative value to the ecological niche of each species or its individual populations. In order to accomplish this, a comparison is made, within a system of coordinates, between the abundance of a species (the number of individuals or the biomass) and an indicator of the temperature, humidity, or some other environmental factor. In this way, it is possible to establish the optimum zone and the limits tolerated by a species (the maximum and minimum for each factor or combination of factors).

As a rule, every species occupies a specific ecological niche, to which it has become adapted by the entire course of evolutionary development. The location that a species (population) occupies in space (spatial niche) is usually called the habitat.

REFERENCES

Odum, E. Osnovy ekologii. Moscow, 1975. (Translated from English.)
Hutchinson, G. E. The Ecological Theater and the Evolutionary Play. New Haven, 1965. Pages 26–78.

N. P. NAUMOV

References in periodicals archive ?
In a mixed planting at advanced ages, therefore, researchers quite likely would observe a smaller fundamental niche, a smaller realized niche, less disparity between the fundamental and realized niches, and a smaller difference between the optimum environment and the inhabited environment than are shown by the present analyses.
Density-dependent selection during the processes of self thinning then carves out a realized niche from that portion of the fundamental niche where a population is competitively exclusive.
Population D, however, also would have a broad realized niche arising from the competitive advantage provided by its innate growth potential; it would be the D genotypes that competitively exclude B and E from their optima and relegate them to suboptimal conditions.
To the extent that the limits of distribution are not controlled through competitive exclusion by other species, A genotypes, for much different reasons than D, would also have a realized niche that encompasses a relatively high proportion of its fundamental niche.
Because emphasis is placed on detecting differentiation of populations, genetic variation is being studied in reference to the realized niche ([ILLUSTRATION FOR FIGURE 13 OMITTED], bottom), and the performance of a population is considered relative to that of all other populations.
Genotypes from D are not only among the fastest growing, but also have a much broader realized niche than all but the ecologically marginal populations.