Biodiversity glossary: A-H
- Accession
- A sample of a crop variety collected at a specific location and time; may be of any size.
- Adaptation
- A genetically determined characteristic that enhances an organism's ability to cope with its environment.
- Alien species
- A species occurring in an area outside of its historically known natural range as a result of intentional or accidental dispersal by human activities. Also known as introduced species.
- Allele
- One of several forms of the same gene.
- Arthropods
- The animal phylum comprised of crustaceans, spiders, mites, centipedes, insects, and related forms. The largest of the phyla, containing more than three times the number of all other animal phyla combined.
- Assemblage
- See term, "Community."
- Avifauna
- All of the birds found in a given area.
- Biodiversity
- The totality of genes, species, and ecosystems in a region or the world.
- Biogeochemical Cycles
- The movement of massive amounts of carbon, nitrogen, oxygen, hydrogen, calcium, sodium, sulfur, phosphorus, and other elements among various living and non-living components of the environment -- including the atmosphere, soils, aquatic systems, and biotic systems -- through the processes of production and decomposition.
- Biogeography
- The scientific study of the geographic distribution of organisms.
- Biological Resources
- Those components of biodiversity of direct, indirect, or potential use to humanity. (Used interchangeably with Biotic Resources)
- Biome
- A major portion of the living environment of a particular region (such as a fir forest or grassland), characterized by its distinctive vegetation and maintained by local climatic conditions.
- Bioregion [bioregional planning]
- A territory defined by a combination of biological, social, and geographic criteria, rather than geopolitical considerations; generally, a system of related, interconnected ecosystems.
- Biota
- All of the organisms, including animals, plants, fungi, and microorganisms, found in a given area.
- Biotechnology
- Any technology that is applied to living organisms to make them more valuable to people.
- Biotic
- Pertaining to any aspect of life, especially to characteristics of entire populations or ecosystems.
- Buffer zone
- The region near the border of a protected area; a transition zone between areas managed for different objectives.
- Carrying capacity
- The maximum number of people, or individuals of a particular species, that a given part of the environment can maintain indefinitely.
- Center of diversity
- Geographic region with high levels of genetic or species diversity.
- Center of dndemism
- Geographic region with numerous locally endemic species.
- Characteristic diversity
- The pattern of distribution and abundance of populations, species, and habitats under conditions where humanity's influence on the ecosystem is no greater than that of any other biotic factor.
- Class
- In taxonomy, a category just beneath the phylum and above the order; a group of related, similar orders.
- Climax community
- The end of a successional sequence; a community that has reached stability under a particular set of environmental conditions.
- Cline
- Change in population characteristics over a geographical area, usually related to a corresponding environmental change.
- Clone
- A population of individuals all derived asexually from the same single parent.
- Co-management
- The sharing of authority, responsibility, and benefits between government and local communities in the management of natural resources.
- Common property resource management
- The management of a specific resource (such as a forest or pasture) by a well-defined group of resource users with the authority to regulate its use by members and outsiders.
- Community
- An integrated group of species inhabiting a given area; the organisms within a community influence one another's distribution, abundance, and evolution. (A Human Community is a social group of any size whose members reside in a specific locality.)
- Comparative advantage
- Relative superiority with which a region or state may produce a good or service.
- Conservation
- The management of human use of the biosphere so that it may yield the greatest sustainable benefit to current generations while maintaining its potential to meet the needs and aspirations of future generations: Thus conservation is positive, embracing preservation, maintenance, sustainable utilization, restoration, and enhancement of the natural environment.
- Conservation of biodiversity
- The management of human interactions with genes, species, and ecosystems so as to provide the maximum benefit to the present generation while maintaining their potential to meet the needs and aspirations of future generations; encompasses elements of saving, studying, and using biodiversity.
- Cosmopolitan
- Widely distributed over the globe.
- Cryogenics
- The branch of physics relating to the effects and production of very low temperatures; as applied to living organisms, preservation in a dormant state by freezing, drying, or both.
- Cultivar
- A cultivated variety (genetic strain) of a domesticated crop plant.
- Cultural diversity
- Variety or multiformity of human social structures, belief systems, and strategies for adapting to situations in different parts of the world.
- Decomposition
- The breakdown of organic materials by organisms in the environment, releasing energy and simple organic and inorganic compounds. About 10 percent of the energy that enters living systems through photosynthesis in plants passes to herbivores, and a fraction of this energy then passes to carnivores. Whether feeding on living or non-living material, however, the detritivores (the organisms consuming non-living material, such as many fungi, bacteria, and earthworms) and consumers break down organic material (such as sugars and proteins) to obtain energy for their own growth, thereby returning the inorganic components (the nutrients) to the environment, where they are again available to plants.
- Demography
- The rate of growth and the age structure of populations, and the processes that determine these properties.
- Donor control
- A predator-prey interaction in which the predator does not control the prey population size.
- Ecosystem
- The organisms of a particular habitat, such as a pond or forest, together with the physical environment in which they live; a dynamic complex of plant, animal, fungal, and microorganism communities and their associated non-living environment interacting as an ecological unit. Ecosystems have no fixed boundaries; instead, their parameters are set according to the scientific, management, or policy question being examined. Depending upon the purpose of analysis, a single lake, a watershed, or an entire region could be an ecosystem.
- Ecotourism
- Travel undertaken to witness sites or regions of unique natural or ecologic quality, or the provision of services to facilitate such travel.
- Ecotype
- A genetically differentiated sub-population that is restricted to a specific habitat.
- Endemic
- Restricted to a specified region or locality.
- Environmental heterogeneity
- The physical or temporal patchiness of the environment. Heterogeneity exists at all scales within natural communities, ranging from habitat differences between the top and underside of a leaf, to habitat patches created by treefalls within a forest, to the pattern of forests and grasslands within a region. The mosaic of habitat patches within an ecosystem is created by such disturbances as fire and storms; differences in microclimate, soils, and history; and both deterministic and random population variation. Patches in early stages of succession provide unique structural habitats and contain different species than those in late-successional stages do.
- Evolution
- Any gradual change. Organic evolution is any genetic change in organisms from generation to generation.
- Ex situ conservation
- A conservation method that entails the removal of germplasm resources (seed, pollen, sperm, individual organisms, from their original habitat or natural environment. Keeping components of biodiversity alive outside of their original habitat or natural environment.
- 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.
- Fauna
- All of the animals found in a given area.
- Flora
- All of the plants found in a given area.
- Frugivore
- An animal that eats fruit.
- Gene
- The functional unit of heredity; the part of the DNA molecule that encodes a single enzyme or structural protein unit.
- Gene bank
- A facility established for the ex situ conservation of individuals (seeds), tissues, or reproductive cells of plants or animals.
- Genetic diversity
- Variation in the genetic composition of individuals within or among species; the heritable genetic variation within and among populations.
- Genotype
- The set of genes possessed by an individual organism.
- Germplasm
- The genetic material, especially its specific molecular and chemical constitution, that comprises the physical basis of the inherited qualities of an organism.
- Grassroots [organizations or movements].
- People or society at a local level, rather than at the center of major political activity.
- Guild
- A group of organisms that share a common food resource.
- Habitat
- The environment in which an organism lives. Habitat can also refer to the organisms and physical environment in a particular place.
- Hybridization
- Crossing of individuals from genetically different strains, populations, or species.