What does the term %26quot;eco-sytem%26quot; mean?

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An ecosystem is a self-sustaining association of plants, animals, and the physical environment in which they live.

Ecosystems are primarily governed by stochastic (chance) events, the reactions they provoke on non-living materials and the responses by organisms to the conditions surrounding them. Thus, ecosystems result from the sums of myriad individual responses of organisms to stimuli from non-living and living elements in the environment. The presence or absence of populations merely depends on reproductive and dispersal success, and population levels fluctuate in response to stochastic events. As the number of species in an ecosystem is higher, the number of stimuli is also higher. Since the beginning of life, in this vision, organisms have survived continuous change through natural selection of successful feeding, reproductive and dispersal behaviour. Through natural selection the planet%26#039;s species have continuously adapted to change through variation in their biological composition and distribution. Mathematically it can be demonstrated that greater numbers of different interacting factors tend to dampen fluctuations in each of the individual factors. Given the great diversity among organisms on earth, most of the time, ecosystems only changed very gradually, as some species would disappear while others would move in. Locally, sub-populations continuously go extinct, to be replaced later through dispersal of other sub-populations. Stochastists do recognise that certain intrinsic regulating mechanisms occur in nature. Feedback and response mechanisms at the species level regulate population levels, most notably through territorial behavior. Andrewatha and Birch (1954) suggest that territorial behaviour tends to keep populations at levels where food supply is not a limiting factor. Hence, stochastists see territorial behavior as a regulatory mechanism at the species level but not at the ecosystem level. Thus, in their vision, ecosystems are not regulated by feedback and response mechanisms from the (eco)system itself and there is no such thing as a balance of nature. 25% 1 Vote

An ecosystem is a self-sustaining association of plants, animals, and the physical environment in which they live. 0% 0 Votes