ENVR 200: Energy and Nutrients in Ecosystems

These flashcards cover key vocabulary and concepts from ENVR 200's lecture on Energy and Nutrients in Ecosystems.

Ecosystem

A community of organisms, their physical (abiotic) environment, and their interactions.

Population

All the members of a species within a given area.

Community

Coexisting populations of different species.

Trophic levels

The hierarchical levels in an ecosystem, comprising primary producers, consumers, and decomposers.

Producers

Organisms that convert sunlight energy to glucose, typically plants and algae.

Primary consumers

Heterotrophs that consume mainly primary producers; herbivores.

Secondary consumers

Heterotrophs that consume mainly primary consumers; predators.

Tertiary consumers

Predators that primarily feed on secondary consumers.

Quaternary consumers

Apex predators at the top of the food chain, consuming tertiary consumers.

Decomposers

Organisms that break down complex organic molecules into simpler forms, returning nutrients to the ecosystem.

Dead organic matter

Biomass and nutrients released by decomposers from formerly living organisms.

Liebig’s Law of the Minimum

The principle stating that only one nutrient limits growth at any one time, the least available nutrient relative to needs.

Gross Primary Productivity (GPP)

The total amount of carbon fixed by plants through photosynthesis.

Net Primary Productivity (NPP)

The amount of primary productivity that occurs after accounting for carbon lost through respiration.

Net Ecosystem Productivity (NEP)

The total amount of carbon fixed by all members of an entire ecosystem.

Energy Transfer Efficiency

The efficiency with which energy is transferred from one trophic level to another.

10% Rule

Approximately 10% of the energy harvested at a lower trophic level is transferred up to the next higher trophic level.

Biomass

The mass (weight) of living organisms within a defined space or framework.

Nutrient cycling

The movement and exchange of organic and inorganic matter back into the production of living matter.

Photosynthesis

The process by which green plants and some other organisms use sunlight to synthesize nutrients from carbon dioxide and water.

Aquatic ecosystems

Ecosystems based in water, including freshwater and marine environments.

Terrestrial ecosystems

Ecosystems found on land, such as forests, grasslands, and deserts.

Carbon cycle

The series of processes by which carbon compounds are interconverted in the environment.