Succession and Disturbance

These flashcards cover key terms and concepts related to the study of succession and disturbance in ecological communities.

Succession

The change in species composition in communities over time due to biotic and abiotic factors.

Primary Succession

Occurs when bare land is colonized for the first time by living organisms, often on substrates like bare rock.

Secondary Succession

Begins in an area where life previously existed but was destroyed by a disturbance, with soil remaining intact.

Climax Community

A stable community that results from the final stage of succession, often determined by climate.

Pioneer Species

The first species to colonize barren areas in primary succession, usually hardy and capable of withstanding harsh environments.

Facilitation

A mechanism in succession where one species makes the environment more suitable for other species to establish.

Inhibition

A process where species make it less suitable for other species to establish, typically by dominating resources or space.

Abiotic Factors

Nonliving factors affecting ecosystems such as climate, soil, and nutrients.

Biotic Factors

Living components in an ecosystem that affect other organisms, such as competition and predation.

Intermediate Disturbance Hypothesis

The theory that suggests species diversity is highest at intermediate levels of disturbance.

Stochasticity

The random nature of disturbances in ecosystems, often leading to unpredictable outcomes in succession.

Superorganism Hypothesis

Clements’ idea that plant communities act as a cohesive unit, moving towards a climax community.

Individualist Hypothesis

Gleason’s idea that communities are formed by individual species responding independently to environmental changes.

Lichens

A symbiotic relationship between a fungus and an alga, commonly acting as a pioneer species in primary succession.

Dryas

A plant genus that serves as an important nitrogen-fixing pioneer species in early successional stages.

Old Field Succession

A type of secondary succession seen in abandoned fields that gradually return to a forested state.

Nutrient Limitation

The shortage of essential nutrients that restricts the growth of organisms in an ecosystem.

Agents of Change

Factors that cause disturbances in an ecosystem, leading to changes in species composition.

Disturbance

An event that causes significant damage to a community, opening up opportunities for other species to establish.

Cyclical Succession

The idea that succession may return to previous stages due to disturbances and the ongoing dynamics of the ecosystem.