VCE Environmental Science key terms

A community of living organisms interacting with each other and with the non-living parts of their environment, such as soil, water and sunlight, functioning together as a unit.

Any living component of an environment that affects organisms, including predators, competitors, food sources, parasites and disease-causing organisms.

Any non-living physical or chemical feature of an environment that influences organisms, such as temperature, light, water availability, salinity, soil type and pH.

The variety of life in a place, measured at three levels: the range of species present, the genetic variation within those species, and the variety of ecosystems they form.

A simple count of how many different species occur in a defined area, without considering how abundant each species is.

A measure of how similar in abundance the species in a community are; evenness is high when no single species dominates the sample.

A group of individuals of the same species living in the same area at the same time and able to interbreed.

All the populations of different species that live and interact together in a particular area.

The maximum population size of a species that a given environment can support indefinitely, given the food, water, space and other resources available.

A resource or condition that is in shortest supply and therefore restricts the growth, distribution or abundance of an organism or population.

The span of an environmental condition, such as temperature or salinity, within which an organism can survive and reproduce; outside it, the organism is stressed or absent.

A linear sequence showing the transfer of energy and matter from producers through a series of consumers, with arrows indicating the direction of energy flow.

A diagram of the interconnected food chains in a community, showing that most consumers feed on more than one type of organism.

A feeding position in a food chain, such as producer, primary consumer or secondary consumer, defined by how many energy-transfer steps an organism is from the sun.

An organism, usually a plant or alga, that makes its own organic food from inorganic substances using energy from sunlight or chemical reactions.

The process by which green plants, algae and some bacteria use light energy to convert carbon dioxide and water into glucose and oxygen.

A diagram that represents numbers, biomass or energy at each trophic level, usually narrowing towards the top because energy and biomass are lost at each transfer.

The proportion of energy at one trophic level that is passed on to the next, typically only about ten per cent because most energy is lost as heat and in waste.

A close, long-term relationship between individuals of two different species, which may benefit both, benefit one at the other's expense, or benefit one while harming neither.

A symbiotic relationship in which both species involved gain a benefit, such as pollinators receiving nectar while transferring pollen for the plant.

A symbiotic relationship in which one organism lives on or in another, gaining nutrients at the host's expense and usually causing it harm.

The gradual, directional change in the species composition of a community over time, from a newly colonised area towards a more stable climax community.

The first organisms to colonise a bare or newly disturbed area; they tolerate harsh conditions and help build soil for later species.

The relatively stable end point of succession, in which the community's species composition stays broadly constant until a major disturbance occurs.

A large-scale region with a characteristic climate and a distinctive set of plant and animal communities, such as tropical rainforest, desert or tundra.

The long-term average pattern of temperature, rainfall, wind and other weather conditions experienced in a region, usually assessed over thirty years or more.

The warming of Earth's surface as certain atmospheric gases absorb and re-emit outgoing infrared radiation, trapping heat in the lower atmosphere.

An atmospheric gas, such as carbon dioxide, methane, nitrous oxide or water vapour, that absorbs and re-emits infrared radiation and so contributes to the greenhouse effect.

The total mass of greenhouse gases, expressed as carbon dioxide equivalent, released directly or indirectly by a person, product, organisation or activity.

The continuous movement of carbon between the atmosphere, oceans, soils, living organisms and rocks through processes such as photosynthesis, respiration, decomposition and combustion.

A reservoir that absorbs and stores more carbon than it releases, such as a growing forest, a peatland or the deep ocean.

A reservoir that releases more carbon to the atmosphere than it absorbs, for example burning fossil fuels or deforested land.

The cycling of nitrogen between the atmosphere, soil and living things, driven by fixation, nitrification, assimilation, ammonification and denitrification.

The conversion of inert atmospheric nitrogen gas into ammonia or other compounds that living organisms can use, carried out by certain bacteria and by lightning.

Nutrient enrichment of a waterway, usually by nitrogen and phosphorus, that triggers algal blooms and can lead to oxygen depletion and fish deaths.

The condition of water measured against physical, chemical and biological indicators such as turbidity, dissolved oxygen, pH, salinity and nutrient concentration.

A species or group of organisms whose presence, absence or condition reveals the health or quality of its environment, such as mayfly larvae indicating clean water.

Meeting present needs without compromising the ability of future generations to meet theirs, by keeping resource use within the capacity of natural systems to renew.

The area of biologically productive land and water needed to supply a population's resources and absorb its wastes, expressed in global hectares.

A natural resource that is replenished by natural processes at a rate comparable to or faster than its rate of use, such as sunlight, wind or sustainably harvested timber.

A natural resource formed over geological timescales and consumed far faster than it is replaced, such as coal, oil, natural gas or mineral ores.

A carbon-rich fuel formed from the buried remains of ancient organisms over millions of years, including coal, petroleum and natural gas.

A region with exceptionally high numbers of endemic species that has already lost a large proportion of its original vegetation and is a priority for conservation.

A species found naturally in one defined area and nowhere else, making it especially vulnerable to local habitat change.

A species moved by humans, deliberately or accidentally, outside its natural range, where it may establish and become invasive.

An introduced species that spreads rapidly and causes ecological or economic harm in its new environment, often because natural controls are absent.

The breaking up of a continuous habitat into smaller, isolated patches, usually by land clearing, roads or urban development, reducing connectivity for wildlife.

A strip of vegetation linking isolated habitat patches, allowing animals to move, disperse and interbreed between them.

A formal process that predicts the likely environmental effects of a proposed development and recommends measures to avoid, reduce or offset them before approval.

A document setting out how a project's environmental risks will be monitored, controlled and reported, including responsibilities, timelines and contingency measures.

The idea that where serious environmental harm is possible but scientific evidence is uncertain, action to prevent harm should not be delayed.

The systematic, repeated collection of data on environmental variables over time so that change can be detected and management adjusted.

Active human intervention to return a degraded ecosystem to a healthier, more self-sustaining state, for example by replanting vegetation or removing weeds.

Partial repair of a degraded site so that it regains some ecological function, though not necessarily the original species composition.

Adjustment in natural or human systems to actual or expected climate change, reducing harm or exploiting beneficial opportunities.

Action that reduces the causes of an environmental problem, such as cutting greenhouse gas emissions to limit climate change, rather than adjusting to its effects.

A long-term shift in global or regional climate patterns, including rising average temperatures, driven largely by human greenhouse gas emissions since industrialisation.