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Five Basic Processes Of An Ecosystem

An ecosystem is alive and dynamic. Although the same processes go on in all ecosystems, different species carry them out in each ecosystem. As ecosystems develop, the pathways become increasingly complex.


All the activities that go on in ecosystems can be classified into five basic processes:


Input: Energy, organic materials, or living organisms that come into the ecosystem fuel all the life and activity. Trees and other plants bring energy into an ecosystem through photosynthesis. Animals that move into an ecosystem, such as deer walking into the forest, are also inputs.


Production: The production of living organisms goes on constantly in every ecosystem. As trees carry out photosynthesis, they grow and become larger. When animals have babies and plants produce seeds, they produce new life.


Storage: Trees "store" wood in their trunks and other organic materials. The soil stores huge amounts of water.


Recycling: When a fallen tree rots on the forest floor or an animal dies and its body decays, then the organic material is recycled in the ecosystem. These organic materials include nutrients and essential materials that become food or energy for the living organisms in the ecosystem.


Ouput: Some energy and resources leave the ecosystem. When a wildfire burns trees, burning wood escapes the ecosystem as smoke and heat energy. Some material stays in the ecosystem, as ashes, minerals, and charred wood. Animals that leave the ecosystem, such as a varied thrush flying to another forest, are also outputs.

USDA Forest Service - Pacific Northwest Research Station
Last Modified: Monday, 16 December 2013 at 14:18:41 CST

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