Introduction to Ecosystems - AP Environmental Science

Sea otters are a keystone species in kelp forest ecosystems. They control sea urchin populations, protecting kelp.

The maximum population size an environment can sustain. Determined by available resources and environmental conditions.

A species whose presence, absence, or abundance reflects a specific environmental condition. Used to monitor ecosystem health and changes.

The process of change in the species structure of an ecosystem over time. Can be primary or secondary depending on starting conditions.

Herbivores that feed on producers. First-level consumers in the energy transfer chain.

A complex network of feeding relationships in an ecosystem. More complex than simple linear food chains.

A non-living component of an ecosystem. Includes temperature, water, sunlight, and soil.

Energy flows through food chains via consumption. Energy decreases at each successive trophic level.

Succession that occurs on surfaces where no soil exists. Starts with pioneer species like lichens and mosses.

Herbivores that feed on producers. First-level consumers in the energy transfer chain.

A large community of plants and animals that occupies a distinct region. Characterized by climate, flora, and fauna patterns.

The variety of life in a particular habitat or ecosystem. Measured at genetic, species, and ecosystem levels.

Biotic and abiotic factors. Living and non-living elements interact in ecosystems.

The maximum population size an environment can sustain. Determined by available resources and environmental conditions.

Sea otters are a keystone species in kelp forest ecosystems. They control sea urchin populations, protecting kelp.

A community of living organisms interacting with their environment. Includes both biotic and abiotic components working together.

The Sun. Solar radiation provides energy for photosynthesis.

A species on which other species in an ecosystem largely depend. Their removal causes significant ecosystem changes.

Energy cannot be created or destroyed, only transformed. First law of thermodynamics applied to ecosystems.

A linear sequence of organisms through which nutrients and energy pass. Shows direct feeding relationships between organisms.

The position an organism occupies in a food chain. Levels include producers, primary, secondary consumers, etc.

The total mass of organisms in a given area or volume. Measured in grams per square meter or similar units.

The impact of a person or community on the environment, measured as land required to sustain their use of natural resources. Measures human demand on Earth's natural resources.

A relationship where one species benefits and the other is unaffected. Like barnacles on whales or birds on cattle.

Only about 10% of energy is transferred from one trophic level to the next. Most energy is lost as heat during transfer.

A predator at the top of a food chain, with no natural predators. Controls prey populations and ecosystem structure.

The process of change in the species structure of an ecosystem over time. Can be primary or secondary depending on starting conditions.

A species whose presence, absence, or abundance reflects a specific environmental condition. Used to monitor ecosystem health and changes.

Decomposers recycle nutrients back into the ecosystem. Essential for maintaining ecosystem productivity.