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Keepers of the Biosphere
Ecosystems are like machines -- working systems composed of living things. Each life form contributes to the whole, providing food for other life forms or consuming others. The machine depends on each member to fulfill a particular job. If something happens to one part, anywhere in the ecosystem, the rest of the ecosystem may suffer.

The BiosphereBiosphere II demonstrated how fragile the balance can become. This grand experiment attempted to replicate natural ecosystems inside a self-contained world. However, the system started to fail several months into the experiment. All parts of the ecosystem were in jeopardy because the experiment's designers had overlooked the importance of every part in the ecosystem, including the microbes.

The delicate balance of microbes in the soil was tipped when too much fertilizer was used to prepare the soil for crops. The microbial population grew too fast and consumed a huge amount of the oxygen inside the Biosphere.

Other species started to die. In desperation, both the team and the external supervisors decided to pump air from outside into the Biosphere. They had failed their primary goal -- all because of their underestimation of the microbes -- one tiny, but crucial part.

To completely understand an ecosystem, it's necessary to examine every component, including the unseen microscopic life. Biologists are beginning to appreciate how important microbes are to the complete system of life on Earth.

The Wonders of Microbes, on the MicrobeWorld Web site, has more information on the role of microbes in ecosystems.

 

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