02.0D BIO Communities & Ecosystem Dynamics - ALL (PART D)

Biotic factor

An environmental factor that is associated with or results from the activities of living organisms.

Abiotic factor

Nonliving or physical factors that shape an ecosystem. For ex. temperature, precipitation, pH, sunlight, chemicals, physical features such as sand or mountains.

Habitat

The environment in which a species lives. For ex. an organisms address.

Niche

In an ecosystem, the unique place occupied by an organism in relationship to all the biotic and abiotic factors.

Resource

Any necessity of life, such as water, nutrients, light, food, or space.

Predation

An interaction in which one organism captures and feeds on another organism

Symbiosis

A close relationship between two species that benefits at least one of the species.

Mutualism

A relationship between two species in which both species benefit

Commensalism

A relationship between two organisms of different species where one benefits and the other is neither harmed nor benefited

Parasitism

A relationship between two organisms of different species where one benefits and the other is harmed

Ecological succession

Series of gradual changes that occur in a community following a disturbance.

Primary succession

Succession that occurs on surfaces where no soil exists.

Pioneer species

First species to populate an area during primary succession

Secondary succession

A type of succession that occurs where an existing community has been cleared by some disturbance that leaves the soil.

Competition

Occurs when organisms attempt to use the same limited ecological resource in the same place at the same time.

Resource partitioning

Occurs when species living in the same area partition resources to avoid direct competition (i.e. three species of Warblers in a spruce tree; different types of plant roots).

Predator

The organism that does the killing in a predation interaction.

Prey

An organism that is killed and eaten by another organism.

Keystone species

A species that influences the survival of many other species in an ecosystem.

Climax community

A stable, mature community that undergoes little or no change in species over time.

Ecological succession

A series of more-or-less predictable changes that occur in a community over time.