Ecosystems

Ecosystem

A self-regulating biological community in which living things interact with their physical environment.

Biome

Very large scale, global ecosystem

Autotroph

Self feeders. Produce their own food by photosynthesis.

Heterotroph

'Other feeders' or consumers. Animals which obtain energy by eating green plants directly or animals that have previously eaten green plants

Detritovore

Eats non-living or decaying organic matter. Includes millipedes, dung beetles or earthworms.

Primary succession

Stages of growth on surfaces where there has been no previous vegetation such as bare rock and sand dunes.

Secondary succession

Growth of vegetation following the destruction or modification of the existing plant community e.g. by fire or landslides

Pioneer species

First plants to colonise bare ground

Climatic climax

Vegetation and animals found if succession is allowed to continue undisturbed.

Arresting factor

A change in conditions that halts natural succession.

Plagioclimax

Succession that is interrupted by human factors e.g. deforestation, slash and burn, grazing of animals.

Biomass

The dry weight of all the organic matter within organisms in an ecosystem

Psammosere

Process of succession in a sand dune system

Trophic pyramid

Shows the weight of organic matter per unit area and shows energy transfers within an ecosystem.

Deciduous woodland

A woodland whose trees that lose their leaves in the winter

Net Primary Productivity (NPP)

The amount of energy captured by green plants in an ecosystem minus the energy used for respiration. Represented as biomass in grammes/m2/year

Surtsey

An island off the coast of Iceland that formed in 1963. An example of primary succession.

Supporting services

Benefits of biodiversity that allow ecosystems to exist, such as primary production, soil formation, and nutrient cycling

Provisioning services

Benefits of biodiversity that humans use, including food, water, wood and fuel

Regulating services

benefits of biodiversity that include climate regulation, flood control, and water purification

Cultural services

benefits of biodiversity that provide aesthetic, spiritual, or recreational value

indicator species

Species that are monitored and serve as early warnings that a community or ecosystem is being degraded.

biotic factors

living parts of an ecosystem e.g. plants, animals, fungi, decomposers

abiotic factors

non-living components of an ecosystem e.g. wind, water, sunlight, temperature