Global Change Vocabulary

Background Extinction rate

Background Extinction rate

Normal extinction of various species as a result of changes in local environmental conditions.

Biodiversity hotspot

An area especially rich in plant species that are found nowhere else and are in great danger of extinction. Such areas suffer serious ecological disruption, mostly because of rapid human population growth and the resulting pressure on natural resources.

Biological extinction

Complete disappearance of a species from the earth. It happens when a species cannot adapt and successfully reproduce under new environmental conditions or when a species evolves into one or more new species.

Biotic pollution

The effect of invasive species that can reduce or wipe out populations of many native species and trigger ecological disruption.

Climate

Physical properties of the troposphere of an area based on analysis of its weather records over a long period (at least 30 years). The two main factors determining an area's climate are its average temperature, with its seasonal variations, and the average amount and distribution of pre-cipitation.

Commercial extinction

Depletion of the population of a wild species used as a resource to a level at which it is no longer profitable to harvest the species.

Conservation

Sensible and careful use of natural resources by humans.

Conservation biology

Multidisciplinary science created to deal with the crisis of maintaining the genes, species, communities, and ecosystems that make up earth’s biological diversity. Its goal are to investigate human impacts on biodiversity and to develop practical approaches to preserving biodiversity.

Conservationist

Person concerned with using natural areas and wildlife in ways that sustain them for current and future generations of humans and other forms of life.

Debt-for-nature-swap

Agreement in which a certain amount of foreign debt is canceled in exchange for local currency investments that will improve natural resource management or protect certain areas in the debtor country from environmentally harmful development.

disturbance

An event that disrupts an ecosystem or community.

Endangered species

Wild species with so few individual survivors that the species could soon become extinct in all or most of its natural range.

Endemic species

Species that is found in only one area. Such species are especially vulnerable to extinction.

Global climate change

Broad term referring to long-term changes in any aspects of the earth’s climate especially temperature and precipitation.

Global warming

Warming of the earth’s lower atmosphere (troposphere) because of increases in the concentrations of one or more greenhouse gases. It can result in climate changes that can last for decades to thousands of years.

Greenhouse effect

Natural effect that releases heat in the atmosphere near the earth’s surface. Water vapor, carbon dioxide, ozone, and other gases in the lower atmosphere absorb some of the infrared radiation radiated by the earth’s surface.

Habitat fragmentation

Breakup of a habitat into smaller pieces, usually as a result of human activities.

HIPPCO

Acronym used by conservation biologists for the six most important secondary causes of premature extiction: Habitat destruction, degradation, and fragmentation; Invasive (nonnative) species; Population growth (too many people consuming too many resources); Pollution; Climate change; and Overexploitation.

Indicator species

Species whose decline serves as early warnings that a community or ecosystem is being degraded.

Mass extinction

Catastrophic, widespread, often global event in which major groups of species are wiped out over a short time compared with normal (background) extinctions.

Nonnative species

Species that migrate into an ecosystem or are deliberately or accidentally introduced into an ecosystem by humans.

Ozone depletion

Decrease in concentration of ozone (O3) in the stratosphere).

Ozone layer

Layer of gaseous ozone (O3) in the stratosphere that protects life on earth by filtering out most harmful ultraviolet radiation from the sun.

Threatened species

Wild species that is still abundant in its natural range but is likely to become endangered because of a decline in numbers.

Tipping point

Threshold level at which an environmental problem causes a fundamental and irreversible shifts in the behavior of a system.