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of terms related to the biodiversity



safe minimum standard

A restriction (taboo, prohibition, harvesting season) which limits the use of resources(resource) to levels that are thought to be safe, e.g. conservation of a sufficient area of habitat to ensure the continued provision of ecological functions and services, at the ecosystem level.

safe or safety

The conditions determined with reasonable certainty to have acceptable or negligible risk to human health or to managed or natural ecosystems(ecosystem).

safe transfer

Transfer that completely eliminates any adverse effect on the conservation and sustainable use of biological diversity.

secondary forest (opp.: primary forest)

Natural forest growth after some major disturbance (e.g. logging, serious fire, or insect attack).

secondary value

The value of ecosystem functions.

seed bank

A facility designed for the ex-situ conservation of individual plant samples through seed preservation and storage.


Natural selection is the differential contribution of offspring to the next generation by various genetic types belonging to the same populations. Artificial selection is the intentional manipulation by man of the fitness of individuals in a population to produce a desired evolutionary response.

selfpollinated (see: inbred)


Fixed or attached; unable to move.

sibling species

Species so similar to each other as to be difficult to distinguish by human observers.


The science of cultivating forest crops (usually timber), based on a knowledge of forest tree characteristics.


Growing vegetation tends to absorb carbon dioxide (CO2) from the atmosphere. Calculating the effect of sinks (by land-use change and forestry) is methodologically complex and still needs to be clarified.

somatic cell

Any cell other than a germ cell.

source country

Country providing genetic resources(genetic resource).


The eggs of certain aquatic organisms or the act of producing such eggs or egg masses.

speciality biotechnology products

Include enzymes, fine chemicals, speciality food products and food ingredients. Non-medical diagnostics for detection of pesticides in the environment and contaminants in food.


Separation of one population into two or more reproductively isolated, independent evolutionary units.


- A group of organisms capable of interbreeding freely with each other but not with members of other species (this is a simplified definition; species concept is much more complex). - A taxonomic rank below a genus, consisting of similar individuals capable of exchanging genes(gene) or interbreeding.

species diversity

The number and variety of species found in a given area in a region.

species richness

The number of species within a region (a term only used as a measure of species diversity, but technically only one aspect of diversity).

species selection

The differential multiplication and extinction of species as a result of differences in certain traits possessed by the organisms belonging to the various species, and causing a spread of the favouring traits through the fauna or flora as a whole.


Expansion of the geographical distribution of a pest (or other organism) within an area. Movement of organisms away from place of birth.


- The ability of a given assemblage of organisms to withstand disturbance without a major change in the number of species or individuals. - A function of several characteristics of community or ecosystem dynamics, including the degree of population fluctuations, the community's resistance to disturbances, the speed of recovery from disturbances, and the persistence of the community's composition through time.

stabilizing selection

Selection favouring individuals in the middle of the distribution of phenotypes in a population and disfavouring the extremes. Also called normalizing selection.


Referring to patterns or processes resulting from random factors.


A specific population or group of populations.

straddling stock

A population of organisms that travels between the exclusive economic zones of two or more countries, or between them and the high seas.


A population of cells all descended from a single cell; also called a clone. A group of organisms within a species or variety distinguished by one or more minor characteristics; a variety of bacterium or fungus used for culturing. The term is mostly associated with cells, bacteria, fungi and viruses(virus), but is sometimes applied to plants.

strong sustainable development principle

The opportunity set for future generations can only be assured if the level of biodiversity they inherit is no less than that available to present generations.


A subdivision of a species; a population or groupings or populations within a species that are distinguishable by morphological characteristics or, sometimes, by physiological or behavioural traits.


The more or less predictable changes in the composition of communities(community) following a natural or human disturbance. For example, after a gap is made in a forest by logging, clearing, fire, or treefall, the initial (or "pioneer") species are often fast-growing and shade-intolerant. These species are eventually replaced by shade-tolerant species that can grow beneath the pioneers. If a community is not further disturbed, the outcome of the successional sequence may be a so-called climax community whose composition is unchanging. In practice, many communities are frequently disturbed and may never reach a climax composition.

sustainable development

Development that meets the needs of the present without compromising the ability of future generations to meet their own needs.

sustainable intensification of animal production systems

The manipulation of inputs to, and outputs from, livestock production systems aimed at increasing production and / or productivity and / or changing product quality, while maintaining the long-term integrity of the systems and their surrounding environment, so as to meet the needs of both present and future human generations. Sustainable agricultural intensification respects the needs and aspirations of local and indigenous people, takes into account the roles and values of their locally adapted genetic resources(genetic resource), and considers the need to achieve long-term environmental sustainability within and beyond the agro-ecosystem.

sustainable use

The use of components of biological diversity in a way and at a rate that does not lead to the long-term decline of biological diversity, thereby maintaining its potential to meet the needs and aspirations of present and future generations.


The close relationship of two organisms in proximity, with one benefiting and the other either benefiting (mutualism), not being significantly affected (commensalism), or being harmed (parasitism).

sympatric (opp.: allopatric)

Occurring in the same place.

sympatric speciation

Speciation via populations with overlapping geographic ranges.


The study of the historical evolutionary and genetic relationships among organisms and of their phenotypic similarities and differences.

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