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biodiversity > glossary
GlossaryAgenda 21: A document accepted by participating nations at UNCED on a wide range of environmental and development issues for the 21st century.
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Amphibian: Common name for any animal of the vertebrate class lying between fishes and reptiles on the evolutionary scale. Emerging from the oceans almost 408 million years ago, amphibians were the first vertebrates (animals with a backbone) to live on land. The class, with about 4,400 existing species, includes three living orders: the tailed amphibians, consisting of the salamanders (including newts) and sirens; the tailless amphibians, which include frogs and toads; and the caecilians, which are worm-like amphibians that are limbless and blind.
With their slender bodies and long tails, some amphibians, such as the salamanders, may be mistaken for lizards and other reptiles. Unlike reptiles, however, amphibians have no scales, and most must stay close to water to survive.
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Animal: Any member of the kingdom Animalia, which comprises all multicellular organisms that obtain energy by ingesting food and that have cells organized into tissues. Unlike plants, which manufacture nutrients from inorganic substances by means of photosynthesis, or fungi, which feed by absorbing organic matter in which they are usually embedded, animals actively acquire their food and digest it internally. Associated with this mode of nutrition are many of the additional features that readily distinguish most animals from other life forms. Specialized tissue systems permit animals to move about freely in search of food or, for those that are fixed in place during most of their lives (sessile animals), to draw the food towards themselves. The well-developed nervous systems and complex sense organs that have evolved in most animals enable them to monitor the environment and, in association with specialized movements, to respond rapidly and flexibly to changing stimuli.
Almost all animal species, in contrast with plants, have a limited growth pattern and reach a characteristically well-defined shape and size at maturity. Reproduction is predominantly sexual, with the embryo passing through a blastula phase.
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Biocultural Reserves: Term coined by Daniel Janzen to describe national parks and protected areas that fully involve local people in the management and education activities conducted within them.
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Biodiversity: The term biological diversity, or biodiversity, refers collectively to the full range of species, genes and ecosystems in a given place.
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Biodiversity Convention: A product of the United Nations Conference on Environment and Development (UNCED), outlining policies aimed at combining the preservation of natural biological diversity with sustainable development of biological resources.
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Biodiversity loss (local): The loss of local breeding populations and/or their habitat, and thus the likely loss of genetic variations and reserve individuals.
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Biological invasions: Processes by which species become established in ecosystems to which they are not native. These species are commonly called biological invaders, invasive species or invading species. They are often weeds, pests and disease-causing organisms.
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Biome: A community of plants and animals in equilibrium with the environmental characteristics - climate, soils, hydrology - of a major geographical area.
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Breeding populations: Groups of individual plants or animals that tend to reproduce among themselves and much less frequently with individuals from other members of the same species. As important sources of migrants and their genetic variability, these separated sub-populations can prove critical to the survival of a species as a whole.
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Carrying capacity: Capacity of an ecosystem to support healthy organisms while maintaining its productivity, adaptability and capability for renewal.
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Conservation (nature): Protection against irreversible destruction and other undesirable changes, including the management of human use of organisms or ecosystems to ensure such use is sustainable.
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Convention on International Trade in Endangered Species (CITES): An agreement drawn up in 1973 to protect a wide variety of animals and plants thought to be at the risk of extinction. It has been signed by 125 nations, and protects nearly 90 species of plants and 400 species of animals, by prohibiting trade in the species or products made from them.
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DDT (Dichlorodiphenyl-trichloroethane): A chlorinated hydrocarbon once widely used as a broad-spectrum insecticide. Introduced during the Second World War as a delousing agent, it proved very effective against diseases such as malaria, yellow fever and typhus, which were spread by insects. Over the longer term, serious side affects became apparent. Being a broad-spectrum product, it killed beneficial insects as well pests and could accumulate in the environment for perhaps 20 years. Although not soluable in water, it was soluable in fat, which allowed it to migrate up the food chain, where it accumulated in the body tissue of the predators. In birds it caused the thinning of eggshells, seriously reducing the breeding success of some species. By the mid-1960s, DDT was found to be widespread in the fatty tissue of the human population, passed on from mother to child through breast milk. Although the link between DDT concentration and human health was not clear, its potential to cause serious ecological disruption was recognised, and it was eventually banned or had its use severely restricted in the developed world.
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Development: A process of economic and social transformation that defies simple definition. Though often viewed as a strictly economic process involving growth and diversification of a country's economy, development is a qualitative concept that entails complex social, cultural, and environmental changes. There are many models of what 'development' should look like and many different standards of what constitutes 'success'.
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Domestic species: Species in which the evolutionary process has been manipulated by humans to meet human needs.
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Earth Summit: Popular name for the United Nations Conference on Environment and Development in (UNCED) held in Rio de Janeiro in 1992.
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Ecological balance: Stability in an ecosystem achieved through the development of equilibrium among its various components. This does not imply that the community is static. It is subject to natural variations associated with ecological succession and other influences such as fire, disease and climate change, but the system is normally sufficiently elastic to make the necessary adjustments without major displacement of the balance. Human intervention that includes the introduction or removal of plants and animals, pollution of the environment and destruction of habitat is now a main cause of imbalance in many ecosystems.
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Ecological evaluation: Determining the value of something; for example, the value of ecosystem functions provided by natural ecosystems to human society.
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Ecological Introductions: The introduction of an organism into an area in which it is not normally resident, usually as a result of human activity.
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Ecology: Originally defined by Ernst Haeckel in 1866, ecology is the study of the relationships that develop among living organisms and between these organisms and the environment.
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Ecosystem: A complex of plants, animals and micro-organisms and their surrounding environment. Ecosystems may be small and simple, such as a small isolated pond, or large and complex, such as a tropical rain forest or a coral reef in tropical seas.
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Ecosystem functions: Capacity of natural processes and components to provide goods and services that could be used or are being used to improve the quality of human life.
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Ecosystem integrity: Continuity and completeness of a complex system, including its ability to perform all essential functions over its entire geographic range; the concept of integrity within a managed system implies the maintenance of key components and processes over time.
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Ecosystem management or ecosystem approach: Deliberate and conscious manipulation or ecosystem structure and/or function, or regulation of human uses of ecological systems, so as to retain defined and desired features and processes, and to meet human needs in an optimal and sustainable way.
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Endangered species: Species of plants or animals threatened with extinction because their numbers have declined to a critical level as a result of overharvesting or because their habitat has drastically changed. That critical level is the minimum viable population (MVP), and represents the smallest number of breeding pairs required to maintain the viability of species.
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Endemic species: Those species that are native to a certain region with restricted distributions and within in restricted range. Outside that restricted range (such as an ecosystem island, or within country boundaries) an endemic species is found nowhere else on earth.
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Environment: A combination of the various physical and biological elements that affect the life of an organism. Although it is common to refer to �the� environment, there are in fact many environments eg, aquatic or terrestrial, microscopic to global, all capable of change in time and place, but all intimately linked and in combination constituting the whole earth/atmosphere system.
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Environmental assessment: Estimation of the magnitude or quality of the natural environment (air, water, soil) or investigation of the way in which one function or activity affects another function or activity.
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Environmental security: A means of achieving long-term social, economic and ethical security through: 1) sustainable use of renewable resources and ecosystem functions; 2) protection from natural hazards; and 3) conservation of other species.
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Environmentally-sound: The maintenance of a healthy environment and the protection of life-sustaining ecological processes. It is based on thorough knowledge and requires or will result in products, manufacturing processes, developments, etc. which are in harmony with essential ecological processes and human health.
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Extinction: The complete and permanent loss of a species to the planet as a whole.
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Fauna: The animal life characteristic of a particular biome. The savanna biome, for example, supports large populations of herbivores, such as wildebeest, antelope and kangaroo, and predators in the form of lions, cheetahs, hyenas and dingoes that prey on them. Any change in a biome, whether natural or human-induced, has the potential to alter the associated fauna.
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Flora: The combination of plants in a particular area. Each biome has a characteristic flora.
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Habitat: The particular environment (e.g. tropical moist forest) in which a species or breeding population naturally lives.
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ICUN Red List: A global listing of endangered species (plant and animal), provided by the World Conservation Union (ICUN).
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Mammal,: Common name applied to any warm-blooded animal belonging to the class that includes human beings and all other animals that nourish their young with milk, are covered with varying amounts of hair, and possess a muscular diaphragm. The class Mammalia, which is represented by about 4,600 living species, is usually divided into three subclasses: the monotremes (egg-laying mammals), the marsupials (usually mammals with pouches), and the placental mammals. The majority of mammals are placental mammals. Mammals have the most highly developed nervous systems, including the brain, of all animals. Most members of the group have four appendages, usually legs. These may be adapted for use as swimming appendages, as in seals, or as wings, as in bats. Some types, however, have two limbs that have been reduced to small vestiges beneath the skin, as in whales, or have been lost altogether, as in sea cows. All mammals, except the monotremes, produce live young that undergo the early stages of development within the body cavity of the mother.
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National conservation strategies: Plans that highlight country-level environmental priorities and opportunities for sustainable management of natural resources, following the example of the World Conservation Strategy published by the World Conservation Union (IUCN) in 1980. Though governments may support preparation for the strategies, they are not bound to follow IUCN's recommendations.
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Organochlorides: A group of organic compounds that contain chlorine (Cl). They have a variety of forms and uses including aerosol propellants, plasticisers, transformer coolants (PCBs) and food packaging (PCVs), but their greatest use was as pesticides, in the form of DDT, Aldrine and Lindane. However, with time many pests have developed immunity to them and it has also become clear that the characteristics that made them good pesticides � persistence, mobility and high biological activity � also posed dangers for the environment. Organochlorides accumulate in the fatty tissue of animals, and through biomagnification in the food chain may reach toxic levels in predators. Because of side effects such as sterility, birth defects, cancer and damage to the nervous system, they have been banned or had their use severely restricted in most parts of the world.
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Organophosphoruus compounds: A group of pesticides that work by blocking the central nervous systems of the organisms exposed to them. Malathion and diazonon are the most commonly used organophosphates. They are highly effective against insects, but break down rapidly in the environment and do not bioaccumulate. For these reasons, they are preferred over organochloride pesticides. Although generally considered safer than the organochlorides, they are highly toxic to humans and other mammals and may be carcinogenic.
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Overexploitation or overharvesting: The use or extraction of a resource to the point of depletion or extinction, or the decimation of a population to a level below the minimum needed for a sustainable yield.
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Pesticides: Chemical products designed to kill or restrict the development of pests. They include fungicides, herbicides and insecticides. Pesticides range from relatively simple elements such as sulphur (S) to complex chemical compounds such as chlorinated hydrocarbons and may be broad-spectrum or narrow-spectrum agents. Pesticides also vary in their persistence in the environment, and in general, the longer they remain chemically stable the greater is their potential for environmental damage. The use of pesticides has undoubtedly benefited society, by preventing disease and improving the food supply. At the same time, ignorance of the environmental impact of pesticides, the indiscriminate use of certain products and inadequate control of the production and use of pesticides has created problems for wildlife and natural vegetation and has threatened human health.
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Precautionary principle: The principle of prevention being better than cure, applied to potential environmental degradation.
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Proper resource pricing: The pricing of natural resources at levels which reflect their combined economic and environmental values.
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Protected area: An area dedicated primarily to protection an enjoyment of natural or cultural heritage, to maintenance of biodiversity, and/or to maintenance of life-support systems.
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Rehabilitation: Conversion of a degraded ecosystem to an alternative state or use, designed to meet a particular management objective, mostly related to biodiversity conservation.
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Renewable resource: A resource that is replaced at a rate which is faster than, or at least as fast as, it can be used. The oxygen (O) in the air, the plants and animals in the environment, the water in the hydrological system and energy from the sun are all renewable, for example.
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Reptile: Common name applied to members of the vertebrate class Reptilia, which includes snakes, lizards, turtles, crocodilians, the tuatara, and numerous extinct fossil species. Among the existing forms are about 2,500 species of snakes, 3,000 of lizards, nearly 250 of turtles and tortoises, and 21 species of crocodilians. They are distributed throughout the temperate and tropical regions of the world; being cold-blooded (dependent on the environment for warmth; see below), very few reptiles can develop or live in colder regions.
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Restoration: Conversion of an ecosystem to the condition it was in prior human disturbance.
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Species: A group of organisms that, because of close genetic and physical similiarities, can naturally mate with each other and produce viable offspring (individuals that can also produce naturally). Within species are often other levels of similiarity, including sub-species, varieties and breeding populations. Organisms that reproduce only through asexual means (such as micro-organisms that reproduce by diving or budding) are sometimes difficult to separate using the species concept.
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Stewardship: The attitude that human beings should see the Earth as a garden to be cultivated not a treasury to be raided.
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Sustainable development: Sustainable development has as many definitions as subscribers. In essence, it refers to economic development that meets the needs of all without leaving future generations with fewer natural resources than those we enjoy today. It is widely accepted that achieving sustainable development requires balance between three dimensions of complementary change:
- Economic (towards sustainable patterns of production and consumption)
- Ecological (towards maintenance and restoration of healthy ecosystems)
- Social (towards poverty eradication and sustainable livelihoods)
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Sustainable management: Management that makes best use of present resource potentials and does not diminish the availability of these resources in the future integrity of the ecosystems through which these resources are provided.
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Sustainable use: Use of an organism, ecosystem or other renewable resource at a rate within its capacity for renewal.
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Taxonomy: The classification of organisms into hierarchical groups. In addition to the description and cataloguing of individual plants and animals, modern taxonomy includes consideration of the causes and effects of the variations among organisms.
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Threatened species: Species that have been assigned to one of three IUCN Red List Categories - either vulnerable, endangered or critically endangered.
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Vulnerability: Extent to which livelihoods are at risk from factors, trends and shocks beyond their control.
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Wetlands: Swamps, marshes, fens, tidal marshes, peatlands and other ecosystems which are dominated by water. The presence of water may be permanent, temporary or seasonal and it may by fresh or salt, but the plant and animal organisms in wetlands have adapted to that situation to create unique communities that reflect the conditions at a specific site. Wetlands provide habitat for fish and wildlife, act as staging areas for migrating wildfowl, filter sediments and control flooding in stream systems and protect the shore from erosion in coastal areas.
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Wilderness: An area still in its natural state, that has not been significantly disturbed by humans. For example, the high Arctic or mountainous areas such as the Himalayas, are sufficiently remote or difficult to access that humans are only temporary visitors, often for recreational purposes.
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World Commission on Environment and Development: Established by the United Nations General Assembly in 1983 to examine international and global environmental problems and to propose strategies for sustainable development. Chaired by Norwegian Prime Minister Gro Harlem Brundtland, the independent commission held meetings and public hearing around the world and submitted a report on its inquiry to the General Assembly in 1987.
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World Summit on Sustainable Development (WSSD): The World Summit on Sustainable Development takes place from 26 August - 4 September 2002 in Johannesburg, South Africa. Governments, UN agencies, and civil society organisations will come together to assess progress since the UN Conference on Environment and Development held in Rio in 1992 (hence the title 'Rio + 10' for the Johannesburg meeting). Sustainable development is defined in the report from the Rio meeting as being 'economic progress which meets all of our needs without leaving future generations with fewer resources than those we enjoy'.
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World Wide Fund for Nature: A private international organisation founded in the 1960s as the World Wildlife Fund, it has been primarily concerned with the survival of endangered species - both plant and animal - but has expanded its interests to include all aspects of conservation.
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