Biotic and Abiotic Factors

Biotic and abiotic factors are interrelated. If one factor is changed or removed, it impacts the availability of other resources within the system.

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Biotic Factors
Biotic, meaning of or related to life, are living factors. Plants, animals, fungi, protist and bacteria are all biotic or living factors.
Abiotic Factors
Abiotic, meaning not alive, are nonliving factors that affect living organisms. Environmental factors such habitat (pond, lake, ocean, desert, mountain) or weather such as temperature, cloud cover, rain, snow, hurricanes, etc. are abiotic factors.
A System
Biotic and abiotic factors combine to create a system or more precisely, an ecosystem. An ecosystem is a community of living and nonliving things considered as a unit.
The Impact of Changing Factors
If a single factor is changed, perhaps by pollution or natural phenomenon, the whole system could be altered. For example, humans can alter environments through farming or irrigating. While we usually cannot see what we are doing to various ecosytems, the impact is being felt all over. For example, acid rain in certain regions has resulted in the decline of fish population.