Environmental Science & Sustainability - Key Terms

A set of vocabulary flashcards covering core environmental science and sustainability concepts drawn from the lecture notes.

Opportunity Cost

The value of the next-best alternative forgone when a decision is made; often framed as short-term vs. long-term consequences.

Sustainability

The capacity of Earth’s natural and human systems to survive, flourish, and adapt into the very long-term future; shaped by our choices.

Solar energy

Energy from the sun that provides warmth and drives photosynthesis; a foundational source for sustainability.

Biodiversity

The variety and adaptability of living organisms in an ecosystem, contributing to resilience and ecosystem services.

Chemical cycling (nutrient cycling)

The circulation of chemicals (nutrients) through the environment, organisms, and back to the environment.

Natural capital

Earth’s stock of natural assets (resources and processes) that support life and human economies.

Natural resources

Materials and energy provided by nature that humans use, including renewables and nonrenewables.

Natural services (ecosystem services)

Ecosystem processes (e.g., air and water purification, climate regulation) that support life and well-being.

Renewable resource

A resource that can be replenished naturally over time; managed by sustainable yield.

Nonrenewable resource

A resource that is not replenished on a human timescale (e.g., fossil fuels, many minerals).

Sustainable yield

The highest rate at which a renewable resource can be used without reducing its future availability.

Ecological footprint

The amount of biologically productive land and water required to supply a population and absorb its wastes indefinitely.

Biocapacity

The capacity of an area to produce renewable resources and absorb wastes; deficits indicate unsustainability.

IPAT model

I = P × A × T; environmental impact equals population × affluence × technology.

Tragedy of the commons

Overuse of shared resources when there are no effective restrictions, leading to depletion.

Open access

Resource use with no limits or restrictions, potentially causing overuse.

Common property

Resources owned or managed collectively; governance is needed to prevent overuse.

Externalities

Costs or benefits of an activity not reflected in market prices (e.g., pollution).

Tipping point

A threshold where a small change can trigger a large, often irreversible, shift in a system.

Overshoot day

The date when humanity’s annual resource use exceeds what Earth can regenerate in that year.

GDP per capita

Gross domestic product divided by the population; a measure of average economic output per person.

Population growth

Increase in the number of people in a population, affecting demand for resources.

Affluence

Level of consumption per person; higher affluence often increases environmental impact.

Point source pollution

Pollution from a single identifiable source (e.g., smokestack).

Nonpoint source pollution

Pollution from diffuse sources (e.g., pesticide drift, runoff).

Biodegradable vs. nonbiodegradable pollution

Biodegradable pollution breaks down naturally; nonbiodegradable persists in the environment.