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The IPBES core glossary provides a standard definition for important terms of broad applicability to IPBES outputs. This core glossary does not replace the assessment-specific glossaries, but is complementary to them. It was developed by a glossary committee established for this purpose.

Environmental assets

Naturally occurring living and non-living entities of the Earth, together comprising the bio-physical environment, that jointly deliver ecosystem services to the benefit of current and future generation.

Essential Biodiversity Variables (EBVs)

Essential Biodiversity Variables are promoted by the Group on Earth Observations Biodiversity Observation Network (GEO BON). The idea behind this concept is to identify, using a systems approach, the key variables that should be monitored in order to measure biodiversity change. The Essential Biodiversity Variables are an intermediate layer of abstraction between raw data, from in situ and remote sensing observations, and derived high-level indicators used to communicate the state and trends of biodiversity.


A condition of an aquatic system in which increased nutrient loading leads to progressively increasing amounts of algal growth and biomass accumulation. When the algae die off and decompose, the amount of dissolved oxygen in the water becomes reduced. The term is sometimes applied more broadly than just to aquatic systems.


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.


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.

Ex-ante assessment

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

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.

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.

Exploratory scenario

See "scenario".

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.


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.

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.


The modification or control of a process or system by its results or effects.

Food security

The World Food Summit of 1996 defined food security as existing “when all people at all times have access to sufficient, safe, nutritious food to maintain a healthy and active life”.


A minimum area of land of 0.05 - 1.0 hectares with tree crown cover (or equivalent stocking level) of more than 10–30 per cent with trees with the potential to reach a minimum height of 2–5 m at maturity in situ. A forest may consist either of closed forest formations where trees of various stories and undergrowth cover a high proportion of the ground or open forest.

Forest degradation

A reduction in the capacity of a forest to produce ecosystem services such as carbon storage and wood products as a result of anthropogenic and environmental changes.

Functional diversity

A long-term reduction in an ecosystem’s structure, functionality, or capacity to provide benefits to people.

Functional traits

Any feature of an organism, expressed in the phenotype and measurable at the individual level, which has demonstrable links to the organism’s function (Lavorel et al. 1997; Violle et al. 2007). As such, a functional trait determines the organism’s response to external abiotic or biotic factors (Response trait), and/or its effects on ecosystem properties or benefits or detriments derived from such properties (Effect trait). In plants, functional traits include morphological, ecophysiological, biochemical and regeneration traits. In animals, these traits include e.g. body size, litter size, age of sexual maturity, nesting habitat, time of activity.

Generalist species

A species able to thrive in a wide variety of environmental conditions and that can make use of a variety of different resources (for example, a flower-visiting insect that lives on the floral resources provided by several to many different plants).

Good quality of life

Within the context of the IPBES Conceptual Framework – the achievement of a fulfilled human life, a notion which may varies strongly across different societies and groups within societies. It is a context-dependent state of individuals and human groups, comprising aspects such as access to food, water, energy and livelihood security, and also health, good social relationships and equity, security, cultural identity, and freedom of choice and action. “Living in harmony with nature”, “living-well in balance and harmony with Mother Earth” and “human well-being” are examples of different perspectives on a “Good quality of life”.


The way the rules, norms and actions in a given organization are structured, sustained, and regulated.


Type of ecosystem characterized by a more or less closed herbaceous (non-woody) vegetation layer, sometimes with a shrub layer, but – in contrast to savannas – without, or with very few, trees. Different types of grasslands are found under a broad range of climatic conditions.


The place or type of site where an organism or population naturally occurs. Also used to mean the environmental attributes required by a particular species or its ecological niche.

Habitat connectivity

The degree to which the landscape facilitates the movement of organisms (animals, plant reproductive structures, pollen, pollinators, spores, etc.) and other environmentally important resources (e.g., nutrients and moisture) between similar habitats. Connectivity is hampered by fragmentation (q.v.).

Habitat degradation

A general term describing the set of processes by which habitat quality is reduced. Habitat degradation may occur through natural processes (e.g. drought, heat, cold) and through human activities (forestry, agriculture, urbanization).

Habitat fragmentation

A general term describing the set of processes by which habitat loss results in the division of continuous habitats into a greater number of smaller patches of lesser total and isolated from each other by a matrix of dissimilar habitats. Habitat fragmentation may occur through natural processes (e.g., forest and grassland fires, flooding) and through human activities (forestry, agriculture, urbanization).


The process of bringing together, and comparing, models or scenarios to make them compatible or consistent with one another.


A row of shrubs or trees that forms the boundary of an area such as a garden, field, farm, road or right-of-way.

Hedonic pricing

An economic valuation approach that utilizes information about the implicit demand for an environmental attribute of marketed commodities.


When used in the ecological sense “homogenisation” means a decrease in the extent to which communities differ in species or functional composition.

Human appropriation of net primary production (HANPP)

The aggregate impact of land use on biomass available each year in ecosystems.

Hybrid model

See "models".

Impact assessment

A formal, evidence-based procedure that assesses the economic, social, and environmental effects of public policy or of any human activity.

Important Bird & Biodiversity Areas

A Key Biodiversity Area identified using an internationally agreed set of criteria as being globally important for bird populations.


A quantitative or qualitative factor or variable that provides a simple, measurable and quantifiable characteristic or attribute responding in a known and communicable way to a changing environmental condition, to a changing ecological process or function, or to a changing element of biodiversity.