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Glossary definitions

The IPBES glossary terms definitions page provides definitions of terms used in IPBES assessments. Some definitions in this online glossary have been edited for consistency. Please refer to the specific assessment glossary for citations/authorities of definitions. 

We invite you to report any errors or omissions to [email protected].

Concept Definition Deliverable(s)
eutrophication

Nutrient enrichment of an ecosystem, generally resulting in increased primary production and reduced biodiversity. In lakes, eutrophication leads to seasonal algal blooms, reduced water clarity, and, often, periodic fish mortality as a consequence of oxygen depletion. The term is most closely associated with aquatic ecosystems but is sometimes applied more broadly.

Europe and Central Asia assessment, Americas assessment
eutrophication

Nutrient enrichment of an ecosystem, generally resulting in increased primary production and reduced biodiversity. In lakes, eutrophication leads to seasonal algal blooms, reduced water clarity, and, often, periodic fish mortality as a consequence of oxygen depletion. The term is most closely associated with aquatic ecosystems but is sometimes applied more broadly.

Global assessment (1st work programme)
evaluation (of models)

see benchmarking and validation”.

Scenarios and models assessment
evapotranspiration

The sum of water loss from both plants and soil measured over a specific area.

Global assessment (1st work programme)
evenness

In ecology, species evenness refers to the similarity of abundances of each species in an environment. It can be quantified by a diversity index as a dimension of biodiversity.

Pollination assessment, Global assessment (1st work programme)
evolutionary adaptation

The process whereby a species or population becomes better able to live in a changing environment, through the selection of heritable traits. Biologists usually distinguish evolutionary adaptation from acclimatisation, with the latter occurring within an organism’s lifetime.

IPBES-IPCC co-sponsored workshop on biodiversity and climate change
evolutionary anthropology

The interdisciplinary study of the evolution of human physiology and human behaviour and the relation between hominids and non-hominid primates. Evolutionary anthropology is based in natural science and social science.

Global assessment (1st work programme)
evolutionary biology

A sub-discipline of the biological sciences concerned with the origin of life and the diversification and adaptation of life forms over time.

Sustainable use assessment, Global assessment (1st work programme)
evolutionary distinctiveness

Is a measure of how isolated a species or groups of species are in a phylogenetic tree. Regions with higher ED have more isolated lineages in them.

Americas assessment
ex-ante assessment

The use of policy- screening scenarios to forecast the effects of alternative policy or management options (interventions) on environmental outcomes.

Scenarios and models assessment
ex-ante assessment

The use of policy-screening scenarios to forecast the effects of alternative policy or management options (interventions) on environmental outcomes.

Land degradation and restoration assessment
ex-post assessment

The use of policy- evaluation scenarios to assess the extent to which outcomes actually achieved by an implemented policy match those expected based on modelled projections,thereby informing policy review.

Scenarios and models assessment
ex-post assessment

The use of policy-evaluation scenarios to assess the extent to which outcomes actually achieved by an implemented policy match those expected based on modelled projections, thereby informing policy review.

Land degradation and restoration assessment
exclusive economic zone

A concept adopted at the Third United Nations Conference on the Law of the Sea (1982), whereby a coastal State assumes jurisdiction over the exploration and exploitation of marine resources in its adjacent section of the continental shelf, taken to be a band extending 200 miles from the shore. The Exclusive Economic Zone comprises an area which extends either from the coast, or in federal systems from the seaward boundaries of the constituent states (3 to 12 nautical miles, in most cases) to 200 nautical miles (370 kilometres) off the coast. Within this area, nations claim and exercise sovereign rights and exclusive fishery management authority over all fish and all Continental Shelf fishery resources.

Americas assessment
exclusive economic zone

An Exclusive Economic Zone (EEZ) is a concept adopted at the Third United Nations Conference on the Law of the Sea (1982), whereby a coastal State assumes jurisdiction over the exploration and exploitation of marine resources in its adjacent section of the continental shelf, taken to be a band extending 200 miles from the shore. The Exclusive Economic Zone comprises an area which extends either from the coast or in federal systems from the seaward boundaries of the constituent states (3 to 12 nautical miles, in most cases) to 200 nautical miles (370 kilometers) off the coast. Within this area, nations claim and exercise sovereign rights and exclusive fishery management authority over all fish and all Continental Shelf fishery resources.

Sustainable use assessment, Global assessment (1st work programme)
exclusive economic zone areas

An Exclusive Economic Zone is a concept adopted at the Third United Nations Conference on the Law of the Sea (1982), whereby a coastal State assumes jurisdiction over the exploration and exploitation of marine resources in its adjacent section of the continental shelf, taken to be a band extending 200 miles from the shore. The Exclusive Economic Zone comprises an area which extends either from the coast, or in federal systems from the seaward boundaries of the constituent states (3 to 12 nautical miles, in most cases) to 200 nautical miles (370 kilometres) off the coast. Within this area, nations claim and exercise sovereign rights and exclusive fishery management authority over all fish and all Continental Shelf fishery resources.

Asia-Pacific assessment
exclusive economic zone

An exclusive economic zone (EEZ) is a concept adopted at the Third United Nations Conference on the Law of the Sea (1982), whereby a coastal State assumes jurisdiction over the exploration and exploitation of marine resources in its adjacent section of the continental shelf, taken to be a band extending 200 miles from the shore. The exclusive economic zone comprises an area which extends either from the coast, or in federal systems from the seaward boundaries of the constituent states (3 to 12 nautical miles, in most cases) to 200 nautical miles (370 kilometres) off the coast. Within this area, nations claim and exercise sovereign rights and exclusive fishery management authority over all fish and all continental shelf fishery resources.

Europe and Central Asia assessment
exclusive economic zone

An Exclusive Economic Zone (EEZ) is a concept adopted at the Third United Nations Conference on the Law of the Sea (1982), whereby a coastal State assumes jurisdiction over the exploration and exploitation of marine resources in its adjacent section of the continental shelf, taken to be a band extending 200 miles from the shore. The Exclusive Economic Zone comprises an area which extends either from the coast, or in federal systems from the seaward boundaries of the constituent states (3 to 12 nautical miles, in most cases) to 200 nautical miles (370 kilometres) off the coast. Within this area, nations claim and exercise sovereign rights and exclusive fishery management authority over all fish and all Continental Shelf fishery resources.

Africa assessment
existence value

The satisfaction obtained from knowing that nature endures.

Scenarios and models assessment
exogenous drivers

Drivers that might affect the outcome of a given policy or decision-making process but are not amenable to influence by that process, and which typically operate at broader spatial scales.

Scenarios and models assessment
exotic pollinator

A pollinator that is transported and introduced accidentally or deliberately by human beings outside its native distributional range.

Pollination assessment
exotics

See Alien species.

Americas assessment
expert

Anyone who has acquired good knowledge of a subject through her/his life experience, including local or indigenous knowledge holders in addition to scientists. It is assumed that the expert is a reliable source of information within a specific domain.

Scenarios and models assessment
expert-based model

Models in which experience of experts and stakeholders is used to describe relationships between input and output variables.

Scenarios and models assessment
exploitation

The consumptive use of any natural resources.

Sustainable use assessment
exploratory scenario

See scenario.

exploratory scenario

Scenarios that examine a range of plausible futures, based on potential trajectories of drivers - either indirect (e.g. socio-political, economic and technological factors) or direct (e.g. habitat conversion, climate change).

Scenarios and models assessment
exploratory scenario

Scenarios that examine a range of plausible futures, based on potential trajectories of drivers - either indirect (e.g. socio-political, economic and technological factors) or direct (e.g. habitat conversion, climate change).

Sustainable use assessment
exposure

The state of having no protection from something potential harmful.

Asia-Pacific assessment
extensive forest management

Low or no input in regeneration or site amelioration is practiced in sparsely populated regions with large forest areas, such as boreal forests (Taiga) of Canada and Siberia, and across much of the world´s major tropical forest biomes.

extensive grazing

Extensive grazing is that in which livestock are raised on food that comes mainly from natural grasslands, shrublands, woodlands, wetlands, and deserts. It differs from intensive grazing, where the animal feed comes mainly from artificial, seeded pastures.

Asia-Pacific assessment, Americas assessment
extensive grazing (lands)

A form of grazing in which livestock are raised on food that comes mainly from natural grasslands, shrublands, woodlands, wetlands and deserts. It differs from intensive grazing, where the animal feed comes mainly from artificial, seeded pastures.

Land degradation and restoration assessment
extent (spatial or temporal)

see spatial scale and temporal scale”.

Scenarios and models assessment
externality

A positive or negative consequence (benefits or costs) of an action that affects someone other than the agent undertaking that action and for which the agent is neither compensated nor penalized through the markets.

Land degradation and restoration assessment, Europe and Central Asia assessment, Global assessment (1st work programme), Asia-Pacific assessment, Sustainable use assessment, Americas assessment
externality

an economic concept of uncompensated environmental effects of production and consumption that affect consumer utility and enterprise cost outside the market mechanism

Invasive alien species assessment
extinction

A population, species or more inclusive taxonomic group has gone extinct when all its individuals have died. A species may go extinct locally (population extinction), regionally ( extinction of all populations in a country, continent or ocean) or globally. Populations or species reduced to such low numbers that they are no longer of economic or functional importance may be said to have gone economically or functionally extinct, respectively. Species extinctions are typically not documented immediately: for example, the IUCN Red List categories and criteria require there to be no reasonable doubt that all individuals have died, before a species is formally listed as Extinct (see IUCN Red List).

Sustainable use assessment
extinction debt

The future extinction of species due to events in the past, owing to a time lag between an effect such as habitat destruction or climate change, and the subsequent disappearance of species.

Global assessment (1st work programme), Global assessment (1st work programme), Europe and Central Asia assessment, Asia-Pacific assessment, Land degradation and restoration assessment, Pollination assessment
extinction

A population, species or more inclusive taxonomic group has gone extinct when all its individuals have died. A species may go extinct locally (population extinction), regionally (e.g. extinction of all populations in a country, continent or ocean) or glo.

extinction

The evolutionary termination of a species caused by the failure to reproduce and the death of all remaining members of the species; the natural failure to adapt to environmental change.

Americas assessment
extractive practice

Extractive practices are defined as the temporary or permanent removal of organisms, part of them or materials derived from them, and may result in mortality of the individual to be used (hunting or whole plant harvest), but does not necessarily do so (e.g. limited collection of plant propagules or shearing and releasing of vicuna).

Sustainable use assessment
extractives

Hydrocarbons (oil and gas) and minerals.

Americas assessment