Life Support Systems
By Tas - tas@oustudent.me.uk
Ecosystems and Regulation
Within the biosphere that provides the life support system for Earth are a multitude of organisms that live in a vast array of physical environments. An environment that is instantly fatal for one organism will provide the ideal circumstances for another organism to survive.
The interaction of these organisms with their particular environment was termed an “ecosystem” in the 1930’s by the botanist Sir Arthur Tansley (Westcott, R., p 21). For ecosystems to be able to actually support life, they consist of an interrelation of the essential components for life – energy flows, cycles and regulatory mechanisms (Westcott, R., p 21).
Regulatory mechanisms are a vital component of all ecosystems as they are the control that ensures the other components interact properly and no one environmental factor can overwhelm the others. The regulation comes as a result of feedback mechanisms – for example if an organism increases its population too much, the ecosystem wont be able to provide enough energy (food) and the organism will starve, thereby reducing its population to sustainable levels. Without these mechanisms, or if they are artificially suppressed, the ecosystem is in danger of losing its resources beyond a point at which it can replenish them.
It is the inherent regulation mechanism within an ecosystem that both keeps the ecosystem stable and allows it to support life. In the case of ecosystems “stable” doesn’t mean unchanging or static, more a system which varies around a mean point (Westcott, R., p 24).
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Reference
Westcott, R., ed. (2004) T210 Block One: The Environment, Risk and Public Health, Milton Keynes, The Open University.
