Chapter 53: Ecosystems and Global Ecology

Ecosystem

Ecosystem

The community of interacting species present in a region, along with the abiotic components of the soil, water and atmosphere

Autotrophs

Organisms that synthesize their own food from inorganic sources

Gross primary productivity (GPP)

Energy that is invested by primary producers in a given area and time period

Net primary productivity (NPP)

Energy that is invested by primary producers in building new tissue or offspring

Biomass

Organic material

Consumers

Eat living organisms

Primary consumers

Eat primary producers

Secondary consumers

Eat primary consumers

Tertiary consumers

Eat secondary consumers

Decomposers

Obtain energy by feeding on the remains of other organisms or waste products

Trophic level

Organisms that obtained energy from the same type of source

Detritus

Dead animals and dead plant tissues

Biomagnification

Increase in concentration in consumers at higher levels in a food chain

Biogeochemical cycle

The path an element takes as it moves from abiotic systems through producers, consumers, and decomposes and bak again

Soil organic matter

A complex mixture of partially and complexity decomposed detritus

Watersheds

Areas drained by a single stream