Term
|
Definition
A non-living, physical factor that may influence an organism or ecosystem; for example, temperature, sunlight, pH, salinity, precipitation. |
|
|
Term
Biochemical oxygen demand (BOD) |
|
Definition
A measure of the amount of dissolved oxygen required to break down the organic material in a given volume of water through aerobic biological activity. |
|
|
Term
|
Definition
Capable of being broken down by natural biological processes; for example, the activities of decomposer organisms. |
|
|
Term
|
Definition
The amount of biological or living diversity per unit area. It includes the concepts of species diversity, habitat diversity and genetic diversity. |
|
|
Term
|
Definition
The mass of organic material in organisms or ecosystems, usually per unit area. Sometimes the term “dry weight biomass” is used where mass is measured after the removal of water. Water is not organic material and inorganic material is usually relatively insignificant in terms of mass. |
|
|
Term
|
Definition
A collection of ecosystems sharing similar climatic conditions; for example, tundra, tropical rainforest, desert. |
|
|
Term
|
Definition
That part of the Earth inhabited by organisms, that is, the narrow zone (a few kilometres in thickness) in which plants and animals exist. It extends from the upper part of the atmosphere (where birds, insects and windblown pollen may be found) down to the deepest part of the Earth’s crust to which living organisms venture. |
|
|
Term
|
Definition
A living, biological factor that may influence an organism or ecosystem; for example, predation, parasitism, disease, competition. |
|
|
Term
|
Definition
The maximum number of a species or “load” that can be sustainably supported by a given environment. |
|
|
Term
|
Definition
A community of organisms that is more or less stable, and that is in equilibrium with natural environmental conditions such as climate; the end point of ecological succession |
|
|
Term
|
Definition
A group of populations living and interacting with each other in a common habitat. |
|
|
Term
|
Definition
A common demand by two or more organisms upon a limited supply of a resource; for example, food, water, light, space, mates, nesting sites. It may be intraspecific or interspecific. |
|
|
Term
|
Definition
A measure of the association between two variables. If two variables tend to move up or down together, they are said to be positively correlated. If they tend to move in opposite directions, they are said to be negatively correlated. Crude birth rate The number of births |
|
|
Term
|
Definition
The number of births/deaths per thousand individuals in a population per year. |
|
|
Term
|
Definition
A general model describing the changing levels of fertility and mortality in a human population over time. It was developed with reference to the transition experienced as developed countries (for example, those of North America, Europe, Australasia) passed through the processes of industrialization and urbanization |
|
|
Term
|
Definition
A generic term for heterogeneity. The scientific meaning of diversity becomes clear from the context in which it is used; it may refer to heterogeneity of species or habitat, or to genetic heterogeneity. |
|
|
Term
|
Definition
The range of genetic material present in a gene pool or population of a species. |
|
|
Term
|
Definition
The range of different habitats or number of ecological niches per unit area in an ecosystem, community or biome. Conservation of habitat diversity usually leads to the conservation of species and genetic diversity. |
|
|
Term
|
Definition
A numerical measure of species diversity that is derived from both the number of species (variety) and their proportional abundance. |
|
|
Term
|
Definition
A numerical measure of species diversity that is derived from both the number of species (variety) and their proportional abundance. |
|
|
Term
|
Definition
The number of years it would take a population to double its size at its current growth rate. A natural increase rate of 1% will enable a human population to double in 70 years. Other doubling times can then be calculated proportionately, that is, the doubling time for any human population is equal to 70 divided by the natural increase rate. |
|
|
Term
|
Definition
The area of land and water required to support a defined human population at a given standard of living. The measure takes account of the area required to provide all the resources needed by the population, and the assimilation of all wastes. (A method of calculation is provided in 3.8.2.) |
|
|
Term
|
Definition
A community of interdependent organisms and the physical environment they inhabit. Entropy A measure of the amount |
|
|
Term
|
Definition
A measure of the amount of disorder, chaos or randomness in a system; the greater the disorder, the higher the level of entropy. |
|
|
Term
Environmental impact assessment (EIA) |
|
Definition
A method of detailed survey required, in many countries, before a major development.Such a survey should include a baseline study to measure environmental conditions before development commences, and to identify areas and species of conservation importance. |
|
|
Term
|
Definition
A state of balance among the components of a system. |
|
|
Term
|
Definition
The natural or artificial enrichment of a body of water, particularly with respect to nitrates and phosphates, that results in depletion of the oxygen content of the water. Eutrophication is accelerated by human activities that add detergents, sewage or agricultural fertilizers to bodies of water. |
|
|
Term
|
Definition
The cumulative, gradual change in the genetic characteristics of successive generations of a species or race of an organism, ultimately giving rise to species or races different from the common ancestor. Evolution reflects changes in the genetic composition of a population over time. |
|
|
Term
|
Definition
The return of part of the output from a system as input, so as to affect succeeding outputs. |
|
|
Term
|
Definition
Feedback that tends to damp down, neutralize or counteract any deviation from an equilibrium, and promotes stability. |
|
|
Term
|
Definition
Feedback that amplifies or increases change; it leads to exponential deviation away from an equilibrium. |
|
|
Term
|
Definition
It may be measured as fertility rate, which is the number of births per thousand women of child-bearing age. Alternatively it may be measured as total fertility, which is simply the average number of children a woman has in her lifetime. |
|
|
Term
|
Definition
The Gaia hypothesis compares the Earth to a living organism in which feedback mechanisms maintain equilibrium |
|
|
Term
|
Definition
An increase in average temperature of the Earth’s atmosphere |
|
|
Term
|
Definition
Gross National Product, the current value of all goods and services produced in a country per year. |
|
|
Term
|
Definition
Those atmospheric gases which absorb infrared radiation, causing world temperatures to be warmer than they would otherwise be (global warming). The natural greenhouse effect is caused mainly by water and carbon dioxide, human-made carbon dioxide, methane, NOx in the atmosphere. |
|
|
Term
|
Definition
The environment in which a species normally lives. |
|
|
Term
Halogenated organic gases |
|
Definition
Usually known as halocarbons that deplete the ozone layer in the stratosphere (e.g. CFCs) |
|
|
Term
|
Definition
The process by which two populations become separated by geographical, behavioural, genetic or reproductive factors. This leades to interrupted gene flow and evolution of new species. |
|
|
Term
|
Definition
Species that usually concentrate their reproductive investment in a small number of offspring, thus increasing their survival rate and live in climax communities. |
|
|
Term
|
Definition
The angular distance from the equator ( north or south of it) as measured from the centre of the Earth |
|
|
Term
|
Definition
Less economically developed country: a country with low to moderate industrialization
and low to moderate average GNP per capita. |
|
|
Term
|
Definition
More economically developed country: a highly industrialized country
with high average GNP per capita. |
|
|
Term
|
Definition
A simplified description designed to show the structure or workings of an object, system or concept. |
|
|
Term
|
Definition
A relationship between individuals of two or more species in which all benefit and none suffer. (The term symbiosis will not be used.) |
|
|
Term
|
Definition
A term sometimes used by economists for natural resources that, if appropriately managed, can produce a “natural income” of goods and services. The natural capital of a forest might provide a continuing natural income of timber, game, water and recreation |
|
|
Term
Non-renewable Natural Capital |
|
Definition
Natural resources that cannot be replenished within a timescale of the same order as that at which they are taken from the environment and used; for example, fossil fuels. |
|
|
Term
Renewable Natural Capital |
|
Definition
Natural capital that has a sustainable yield that is less than or equal to or less than natural productivity: LIKE TIMBER OR SUNLIGHT |
|
|
Term
Replenishable Natural Capital |
|
Definition
NON-living natural resources that depend on the energy of the sun |
|
|
Term
|
Definition
The rate of increase in population as defined by (crude birth - crude death)/10 |
|
|
Term
|
Definition
An organism's share of a natural habitat and the resources shared within it. An ECOLOGICAL niche is the role of the organism in that habitat |
|
|
Term
|
Definition
A relationship between an organism and its host where much of its food is gained from it. |
|
|
Term
|
Definition
The movement of the earth's eight major and several minor plates of the lithosphere in relation to each other and to the partially mobile asthenosphere below. |
|
|
Term
|
Definition
The addition of a substance or an agent by human activity at a rate that is faster than the rate that the environment can render it harmless, and has a n appreciable effect on its inhabitants. |
|
|
Term
Non-point source Pollution |
|
Definition
Pollution from widely-dispersed sources (car exhaust) |
|
|
Term
|
Definition
The release of pollutants from a clearly identifiable site |
|
|
Term
|
Definition
The group od organisms of the same species living at the same area at the same time, which are capable of interbreeding |
|
|
Term
Gross Primary Prductivity |
|
Definition
The total gain in biomass fixed by green plants |
|
|
Term
|
Definition
The TOTAL GAIN in biomass or energy per unit area per unit time, which could be through photosynthesis in primary producers or absorption through consumers |
|
|
Term
Gross secondary productivity |
|
Definition
The total amount of biomass fixed per unit area per unit time through absorption |
|
|
Term
|
Definition
The gain in biomass per unit area per unit time after allowing respiratory losses |
|
|
Term
|
Definition
The gain in biomass per unit area per unit time by autotrophs after allowing respiratory losses and are available to the next trophic level |
|
|
Term
Net secondary productivity |
|
Definition
The gain in biomass/area/time after allowing repiratory losses by consumers after allowing respiratory losses |
|
|
Term
|
Definition
A species that tend to spread their reproductive investment over a large amount of offspring so that they make opportunistic use of the short-lived resources and colonize a new habitat |
|
|
Term
|
Definition
The set of communities that succeed one another over thr course of succession over a period of time |
|
|
Term
|
Definition
The hazziness in the atmosphere caused by air pollutants. Photochemical smog is caused by the action of UV light on the products of internal combustion engines that cause respiratory and optical irritation |
|
|
Term
|
Definition
An arbitrary group of individuals who share similar characteristics such as geographical location, cultural/ religious ,/ social / political value systems |
|
|
Term
|
Definition
The part of the lithosphere covered by mineral and organic particles where plants grow. It is created by the physical, chemical, and biological action on rocks over a long period of time. |
|
|
Term
|
Definition
The vertical section of a soil from surface to parent material revealing soil horizons |
|
|
Term
|
Definition
The process through new species occur |
|
|
Term
|
Definition
The group of individuals that are capable of interbreeding |
|
|
Term
|
Definition
The state of an ecosystem that has the tendency to return to a previous equilibrium condition following a disturbance |
|
|
Term
|
Definition
The condition of an open system where there are no changes on the slong term but many oscillations in the short term. There are continuous inputs and outputs of energy, but the system more or less remains in a constant state. |
|
|
Term
|
Definition
The orderly process of change in a community. This change often results in the physical change in the environment,allowing another community that is often more complex to establish themselves over the previous community via competition. |
|
|
Term
|
Definition
The use of natural resources at a rate that allows natural regeneration and minimizes damage to the environment. |
|
|
Term
|
Definition
The arrangement or patterning of plant communities or ecosystmes in parallel bands in response to change, over distance, in some environmental factor. EG: biomes of the world change according to latitude and climate, the plants on a mountain change according to altitude, while the plants around a pond might change according to moisture |
|
|