Biodiversity BC - Conserving the Variety of Life


flag-turnstone.jpg Photo Credit: Don Enright

"Black Turnstones"
Arenaria melanocephala

Foraging on a Vancouver Island beach.



: non-living chemical and physical factors in the environment, including solar radiation, water, atmospheric gases, soil and physical geography.

Adaptation: any feature of an organism that substantially improves its ability to survive and leave more offspring. Also, the process of a species' or a population's genetic variability changing due to natural selection in a manner that improves its viability.

Adaptive divergence: divergence as a result of adaptive change.

Alien species: a species occurring in an area outside its historically known natural range as a result of intentional or accidental dispersal by humans (i.e., movement of individuals) or direct human activities that remove a natural barrier (e.g., creation of a fish ladder to allow fish to move past a waterfall). Also known as an exotic or introduced species.

Allele: a form of a gene.

Anadromous: fish species that spawn (breed and lay eggs) in freshwater environments, but spend at least part of their adult life in a marine environment.

Arthropod: invertebrate with external skeleton and jointed segmental appendages.

Benthic: the bottom substrate of an aquatic environment.

Beringia: the entire region between the Kolyma River in eastern Siberia and the Mackenzie River in the Canadian Northwest Territories, including the intervening continental shelf where it is shallower than approximately 200 m.

Biodiversity: the variety of species and ecosystems on earth and the ecological processes of which they are a part, including ecosystem, species and genetic diversity components.

Biofilm: a thin (0.01-2 mm) yet dense surface layer of microbes, organic detritus and sediment in a mucilaginous matrix of extracellular polymeric substances held together with non-carbohydrate components secreted by microphytobenthos and benthic bacteria; found in some intertidal areas.

Biogeoclimatic Ecosystem Classification [BEC]: a multilevel, integrated system of ecological classification utilizing climate, vegetation and soils data to produce a classification of ecosystems.

Biogeoclimatic zone: the broadest classification in the Biogeoclimatic Ecosystem Classification, representing large geographical areas that share similar climate and vegetation.

a major regional ecosystem, characterized by its distinctive vegetation, a particular plant formation and associated animals, microbes and physical environment (e.g., grasslands, tundra, savannah). A biome is a subdivision of a continent on the basis of major differences in the life form of the vegetation, where life forms reflect the regional climates and soils.

Bivalve: having a shell composed of two parts (valves).

Bryophyte: primitive plant in the plant phylum Bryophyta, lacking a vascular system and typically growing in moist habitats.


Cambium: a layer of actively dividing cells situated between xylem and phloem of a woody plant. As the cells develop, they add a new layer of woody material on the inner side of the root or stem (mainly xylem) and a new layer of bark (phloem and associated tissues) on the outer side.

Census population size: the actual number of individuals in a population.

Climate change: a statistically significant variation in either the mean state of the climate or in its variability, persisting for an extended time period (typically decades or longer).

Climate envelope:
describes the area of suitable climate for a species or ecosystem in terms of temperature and precipitation. Climate envelope models determine the current distribution of the species or ecosystem, then map the location of this same envelope under a climate change scenario.

Coarse woody debris [CWD]: large pieces of wood, generally greater than 10 cm in diameter, on or near the forest floor, including sound or rotting logs, stumps and large branches that have fallen or been cut. In aquatic environments, this material is called large woody debris (LWD) or large organic debris.

Community: an integrated group of living organisms inhabiting a given part of an ecosystem.

Composition: the identity and variety of an ecological system. Descriptors of composition are typically lists of species
resident in an area or an ecosystem.

Conifer: a cone-bearing tree having needles or scale-like leaves; usually evergreen.

the degree to which the habitat or terrain is linked so as to facilitate the movement of individuals of a species from one place to another.

Conservation concern: globally or provincially critically imperilled (G1 or S1), imperilled (G2 or S2), or vulnerable
(G3 or S3). Species of global conservation concern are ranked G1 to G3. Species of provincial conservation concern are ranked S1 to S3.

Conservation status: a measure of the risk of regional extirpation or global extinction for an element of biodiversity, population, subspecies and ecosystem.

Cryptogamic crust: a thin layer of lichens, moss, liverworts, algae, fungi and bacteria found in undisturbed semiarid ecosystems. Also known as microbial, microfloral, microphytic or cryobiotic crust.

Cumulative impact: changes to the environment that are caused by a human action in combination with other past,
present and future human actions.

Decomposition: the breakdown of dead plant and animal matter, into their inorganic constituents, such as carbon and nitrogen.

Detritivore: an organism that feeds solely on non-living organic material.

Dicot [dicotyledon]: a flowering, vascular plant that has two cotyledons (primary embryonic leaves) in its seed.

Disjunct: disjoined or separated from the normal range.

Dispersal: movement of individual organisms to different localities.

DNA [Deoxyribonucleic Acid]: a long organic molecule composed of nucleotides in a linear order that contributes the genetic information of cells; capable of replicating itself and of synthesizing ribonucleic acid (RNA).

Duff: decaying vegetable matter that covers forest ground.

Ecological community: a recurring plant community with a characteristic range in species composition, specific diagnostic species, and a defined range in habitat conditions and physiognomy or structure.

Ecosystem: is a dynamic complex of plant, animal and microorganism communities and their abiotic environment,
all interacting as a functional unit.

Ecosystem conversion: replacement of natural communities with human-dominated systems (e.g., intensive agriculture) or physical works (e.g., mines, urban areas).

Ecosystem degradation: direct change to the structure of natural systems (e.g., through forest harvesting or water

Ecotype: a distinct entity of an organism that is closely linked (in its characteristics) to the ecological surroundings it

Ectomycorrhizal: see Mycorrhizae.

Effective population size [Ne]: a quantity that estimates the number of individuals contributing genes to future generations.

found only in a specified geographic region.

Endomycorrhizal: see Mycorrhizae.

Environmental contamination: occurs when substances are released intentionally, accidentally or as a by-product,
into natural systems.

Enzyme: a protein molecule produced in living cells that accelerates the rate of reactions without being consumed
in that reaction.

Ephemeral: lasting for a brief period of time (e.g., a seasonal pond).

Estuary: a partially enclosed body of coastal water, where salt water is measurably diluted by mixing with river runoff.

Eutrophication: a process by which a water body becomes rich in dissolved nutrients, often leading to algal blooms,
low dissolved oxygen and changes in community composition. Occurs naturally, but can be accelerated
by human activities that increase nutrient inputs to the water body.

Evolutionarily significant unit: a population within a species that has very different behavioural and phenological
traits based on genetic uniqueness.

Extinct: no longer living.

Extirpation: the elimination of a species or subspecies from a specified area, but not from its entire global range.

a nutrient-medium peatland ecosystem dominated by sedges and brown mosses, where mineral-bearing groundwater is within the rooting zone of plants.

Fire regime: the way in which fire interacts in an environment.

Function[s]: the result of ecological and evolutionary processes (e.g. nutrient cycling is a function that involves processes such as photosynthesis, herbivory, predation and decomposition).

Fungi: single-celled, multinucleate or multicellular organisms that lack chlorophyll and vascular tissues; includes yeasts, moulds, smuts and mushrooms.

the functional unit of heredity; the part of the DNA molecule that encodes a single enzyme or structural protein unit.

Gene flow: the transfer of genes from one population or locality to another.

Genetic drift: a change in the genetic composition of a population resulting from random events.

Genetic variability: the number and relative abundance of genes within a species or population.

Genotype: genetic basis of a trait in an organism.

Geographically marginal: a species or population that is at the edge of its range. Also known as peripheral.

Georgia Basin: the geographical area that encompasses the Straits of Georgia and Juan de Fuca and the land around them (i.e., eastern Vancouver Island, the lower mainland and the Pacific mountain ranges).

Groundwater: water in the soil and underlying geological strata.

the natural environment in which an organism normally lives.

Herbivore: an organism that obtains nutrition and energy by eating plants.

Herbivory: plant-feeding.

Holocene: an epoch of the Quaternary period, spanning the interval after the last glaciation, typically from 10,000 years ago to the present.

Hybrid suture zone: geographic zone where hybridization occurs.

Hybridization: crossing of individuals from genetically different strains, populations or species.

Hyphae: fine, threadlike, tubular and often branched filaments of fungal cells that make up the mycelium, or fruiting body, of a fungus.

Hyporheic zone: the saturated sediment zone between groundwater and surface waters.

Impervious surface [impervious area]:
an area covered by impenetrable materials such as asphalt, concrete, brick and stone, which seal surfaces, repel water and prevent precipitation and meltwater from infiltrating soils. Impervious areas are usually constructed surfaces (e.g., rooftops, sidewalks, roads, parking lots). Compacted soils can also be highly impervious.

Impoundment: the confinement of water by a dam.

Intertidal: the area between the mean high tide line and the mean low tide line, or zero tide, where the benthic substrate is regularly exposed through tidal action.

Invasive alien species: alien species that threaten biodiversity due to their ability to spread and out-compete or otherwise impact native species.

Invertebrate: an animal without a backbone.

landscapes derived from soluble bedrock; typically limestone, but also dolomite, marble and gypsum.

Key element: organisms, groups of organisms, and ecological processes known to play essential and/or disproportionately large roles in the functioning of ecosystems.

Keystone species: a species with an effect on its environment and associated species disproportionate to its relative abundance and biomass.

Large woody debris [LWD]:
see Coarse woody debris.

Lichen: an organism consisting of an outer fungal body enclosing photosynthetic algae.

Liverwort: any of a class (Hepaticae) of bryophytic plants characterized by a thalloid gametophyte or sometimes an upright leafy gametophyte that resembles a moss.

Macroalgae: macroscopic algae, commonly known as seaweed.

Macrophyte: a large aquatic plant.

Major Drainage Area [MDA]: an area that drains all precipitation received as either runoff or base flow (groundwater sources) into a particular river or set of rivers. Also known as a drainage basin, catchment area or watershed.

Marl: soft calcium carbonate usually mixed with varying amounts of clay and other impurities.

Megafauna: a general term for the large terrestrial vertebrates inhabiting a specified region.

Migration: movement from one place of residence to another on a regular basis.

Mollusc: a taxonomic group of invertebrate organisms that includes clams, mussels, snails and slugs.

Monocot [monocotyledon]: a flowering, vascular plant that has a single cotyledon (primary embryonic leaf) in its seed.

Morphological: relating to the form and structure of living organisms.

Mutation: changes to the DNA sequence of the genetic material of an organism.

mutually beneficial associations between the hyphae of a fungus and the roots of a plant. In ectomycorrhizal associations, the fungus grows on the outer surface of the plant roots. In endomycorrhizal associations, the fungus penetrates the roots.


Native species:
a species that naturally occurs in an area as a result of its own movements (unaided by direct human actions allowing it to move past a natural barrier).

Natural disturbance: a natural event that directly alters the structure of ecosystems (e.g., fire, flood, insect outbreak, landslide).

Natural selection: the process by which favorable heritable traits become more common in successive generations of a population of reproducing organisms, and unfavorable heritable traits become less common, due to the differential contribution of offspring to the next generation by various genetic types within populations.

Nematodes: non-segmented roundworms in the phylum Nematoda.

Non-vascular plant: a plant without specialized tissues for conducting water and nutrients.

Nutrient cycling: circulation or exchange of elements, such as nitrogen and carbon dioxide, between non-living and living parts of the environment.

Obligate: restricted to a particular set of environmental conditions, without which an organism cannot survive.

Patch: in landscape ecology, a particular unit with identifiable boundaries that differs from its surroundings in one or more ways.

Pelagic: pertaining to the open ocean.

Peripheral: See Geographically marginal.

Phenotype: physical manifestation of a trait in an organism, determined by genotype and environment.

Phenotypic: relating to phenotype.

Photosynthesis: the conversion of light energy into chemical energy by living organisms.

Pleistocene: the first epoch of the Quaternary period after the Tertiary period and Pliocene epoch and before the Holocene epoch, spanning the interval from 1.7 million years ago to 10,000 years ago.

Pollination: the process in which pollen is transferred from an anther of male plant to a receptive stigma of a female plant.

Population: a group of individuals with common ancestry that are much more likely to mate with one another than with individuals from another such group.

Predator-prey system: a system involving interactions between predators and their prey. An intact predatorprey system is one in which all of the native species are present, and with no alien species that plays a role as either predator or prey relative to the others. A relatively intact predator-prey system is one that is missing only one species, and with no alien species that plays a role as either predator or prey relative to the others, and where the loss of the species has not substantially altered the importance of predator-prey interactions to the populations of the remaining species.

Primary consumer: an organism that gets its energy from primary producers (e.g., plants, algae).

Primary production: the production of organic compounds from atmospheric or aquatic CO2, primarily through the process of photosynthesis.

Processes: actions or events that shape ecosystems, such as disturbances, predation and competition.

Refugium [pl. refugia]: an area that remained unchanged while areas surrounding it changed markedly (e.g., an area that remained ice-free while surrounding areas were glaciated).

Relict species: the remnants of a formerly widespread species, typically now found in very restricted or isolated areas.

Riparian: a zone of transition from an aquatic to a terrestrial system, dependent upon surface or subsurface water. Riparian areas may be located adjacent to lakes, estuaries, rivers, or ephemeral, intermittent or perennial streams.

a fish belonging to the family Salmonidae.

Seral stages: in a forestry context, the series of plant community conditions that develop during ecological succession from bare ground (or major disturbances) to the climax stage. Three main stages are typically recognized: early-seral, mid-seral and late-seral.

Special element: elements of biodiversity that are of global significance either because they are important habitat for seasonal concentrations of species or because they are uncommon or even unique on a global scale owing to their unusual ecological characteristics.

Speciation: the formation of new species.

Species: in most living organisms, each species represents a complete, self-generating, unique ensemble of genetic variation, capable of interbreeding and producing fertile offspring.

Species disturbance: the alteration of the behaviour of species due to human activities.

Species mortality: the direct killing of individual orgasms.

Species richness: the number of species within a specified area.

Steppe: vegetation dominated by grasses and occurring where the climate is too dry to support tree growth.

Structure: the physical organization or pattern of a system (e.g., the size and spacing of trees in a landscape).

Subspecies: a geographically defined aggregate of local populations that differs from other such subdivisions of a species; the lowest taxonomic rank given a formal scientific name.

Succession: a series of dynamic, non-seasonal changes in ecosystem structure, function, and species composition in a given area over time.

Taxon [pl. taxa]:
any one of the categories used in naming and classifying organisms (e.g., phylum, class, order, family, genus, species, subspecies, variety).

Taxonomic group: a group of organisms at the same level of organization in biological classification.

Topography: the shape of the surface of the earth.

Transpiration: the evaporation of water from the aerial parts of plants, especially the leaves, but also stems, flowers and roots.

Trophic: pertaining to food or eating.

Tundra: a level or rolling treeless plain characteristic of Arctic and subarctic regions; consists of black, mucky soil with a permanently frozen subsoil, and a dominant vegetation of mosses, lichens, herbs and dwarf shrubs. Also, a similar region confined to mountainous areas above timberline.

a hoofed mammal.

Vascular plant: a plant with specialized tissues for conducting water and nutrients.

Vertebrate: an animal with a backbone.