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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.


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.