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Dinosaur Home A-Z Dinosaurs List Ecosystem Dinosaur
Ecosystem
In ecology, an ecosystem is a naturally occurring assemblage of organisms
(plant, animal and other living organisms—also referred to as a
biotic community or biocoenosis) living together with their environment
(or biotope), functioning as a loose unit.
An ecosystem is a dynamic and complex whole, interacting as an ecological
unit. Some consider this the basic unit in ecology: a structured functional
unit in equilibrium, characterized by energy and matter flows between
its constituent elements. Others consider this vision limited.
The term ecosystem first appeared in a 1935 publication by the British
ecologist Arthur Tansley (Tansley, 1935). However, the term had been coined
already in 1930 by Tansley's colleague Roy Clapham, who was asked if he
could think of a suitable word to denote the physical and biological components
of an environment considered in relation to each other as a unit. Tansley
expanded on the term in his later work, adding the ecotope concept to
define the spatial context of ecosystems (Tansley, 1939). Modern usage
of the term derives from the work of Raymond Lindeman in his classic study
of a Minnesota lake (Lindeman, 1942).
The organisms in an ecosystem are usually well balanced with each other
and their environment. This balance is achieved through various types
of symbiosis, such as predation, parasitism, mutualism, commensalism,
competition, and amensalism. Introduction of new elements, whether abiotic
or biotic, into an ecosystem tend to have a disruptive effect. In some
cases, this can lead to ecological collapse and the death of many native
species. The abstract notion of ecological health attempts to measure
the robustness and recovery capacity for an ecosystem
The size of an ecosystem can vary widely. It may be a whole forest, as
well as a small pond. Different ecosystems are often separated by geographical
barriers, like deserts, mountains or oceans, or are isolated otherwise,
like lakes or rivers. As these borders are never rigid, ecosystems tend
to blend into each other. As a result, the whole earth can be seen as
a single ecosystem, or a lake can be divided into several ecosystems,
depending on the scale used.
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