environmental science
autotroph
an organism that produces complex organic compounds from simple inorganic molecules using energy from light or inorganic chemical reactions.
appropriated carrying capacity
another name for the Ecological Footprint, but often used in referring to the imported ecological capacity of goods from overseas.
carbon sink
any carbon storage system that causes a net removal of greenhouse gases from the atmosphere.
anaerobic digestion
the biological degradation of organic materials in the absence of oxygen to yield methane gas (that may be combusted to produce energy) and stabilised organic residues (that may be used as a soil additive).
aquaculture
the cultivation of aquatic organisms under controlled conditions.
calorific value
the energy content of a fuel measured as the heat released on complete combustion.
bagasse
the fibrous residue of sugar cane milling used as a fuel to produce steam in sugar mills.
biofuel
the fuel produced by the chemical and/or biological processing of biomass. Biofuel will either be a solid (e.g. charcoal), liquid (e.g. ethanol) or gas (e.g. methane).
biophysical
the living and non-living components and processes of the ecosphere. Biophysical measurements of nature quantify the ecosphere in physical units such as cubic metres, kilograms or joules.
biomass
the materials derived from photosynthesis (fossilised materials may or may not be included) such as forest, agricultural crops, wood and wood wastes, animal wastes, livestock operation residues, aquatic plants, and municipal and industrial wastes; the quantity of organic material present in unit area at a particular time mostly expressed as tons of dry matter per unit area; organic matter that can be used as fuel.
carrying capacity
the maximum population that an ecosystem can sustain cf. biocapacity.
biotic potential
the maximum reproductive capacity of a population under optimum environmental conditions.
air pollution
the modification of the natural characteristics of the atmosphere by a chemical, particulate matter, or biological agent.
biogeochemical cycles
the movement of chemical elements between organisms and non-living components of the atmosphere, aquatic systems and soils.
acid mine drainage
the outflow of acidic water from metal mines or coal mines.
biosphere
the part of the Earth, including air, land, surface rocks, and water, within which life occurs, and which biotic processes in turn alter or transform.
acclimation
the process of an organism adjusting to chronic change in its environment.
carbon stocks
the quantity of carbon held within a carbon pool at a specified time.
algal bloom
the rapid and excessive growth of algae; generally caused by high nutrient levels combined with other favourable conditions. Blooms can deoxygenate the water leading to the loss of wildlife.
baseload
the steady and reliable supply of energy through the grid. This is punctuated by bursts of higher demand known as "peak-load". Supply companies must be able to respond instantly to extreme variation in demand and supply, especially during extreme conditions. Gas generators can react quickly while coal is slow but provides the steady "baseload". Renewable energies are generally not available on demand in this way.
abiotic
non-living chemical and physical factors of the environment (see also biotic).
boreal
northern; often referring to cold temperate Northern Hemisphere forests that grow where there is a mean annual temperature < 0°C.
anaerobic
not requiring air or oxygen; used in reference to decomposition processes that occur in the absence of oxygen.
cell
(biology) the structural and functional unit of all known living organisms and is the smallest unit of an organism that is classified as living
birth rate
number of people born as a percentage of the total population in any given period of time; number of live births per 1000 people.
biosolids
nutrient-rich organic materials derived from wastewater solids (sewage sludge) that have been stabilised through processing.
catchment area
the area that is the source of water for a water supply whether a dam or rainwater tank.
carbon cycle
the biogeochemical cycle by which carbon is exchanged between the biosphere, geosphere, hydrosphere, and atmosphere of the Earth.
biological productivity
(bioproductivity) the capacity of a given area to produce biomass; different ecosystems (i.e. pasture, forest, etc.) will have different levels of bioproductivity. Biological productivity is determined by dividing the total biological production (how much is grown and living) by the total area available.
bioregion
(ecoregion) an area comprising a natural ecological community and bounded by natural borders.
baffle
(landscape design) an obstruction to trap debris in drainage water.
batters
(landscape design) the slope of earthworks such as drainage channels.
agroforestry
(sustainability) an ecologically based farming system, that, through the integration of trees in farms, increases social, environmental and economic benefits to land users.
application efficiency
(sustainability) the efficiency of watering after losses due to runoff, leaching, evaporation, wind etc.
avoidance
(sustainability) the first step in the waste hierarchy where waste generation is prevented (avoided).
carbon equivalent (
) - obtained by multiplying the CO2-e by the factor 12/44.
anoxic
- with abnormally low levels of oxygen.
carbon footprint - a measure of the carbon emissions that are emitted over the full life cycle of a product or service and usually expressed as grams of CO
.
bioelement
an element required by a living organism.
Brundtland Commission Report
a UN report, Our Common Future, published in 1987 and dealing with sustainable development and the policies required to achieve it. The definition of the term in the report is "sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs."
calorie
a basic measure of energy that has been replaced by the SI unit the joule; in physics it approximates the energy needed to increase the temperature of 1 gram of water by 1 °C which is about 4.184 joules. The Calories in food ratings (spelled with a capital C) and nutrition are 'big C' Calories or kcal.
aquifer
a bed or layer yielding water for wells and springs etc.; an underground geological formation capable of receiving, storing and transmitting large quantities of water. Aquifer types include: confined (sealed and possibly containing "fossil" water); unconfined (capable of receiving inflow); and Artesian (an aquifer in which the hydraulic pressure will cause the water to rise above the upper confining layer).
adaptation
a characteristic of an organism that has been favoured by natural selection.
biological oxygen demand (BOD)
a chemical procedure for determining how fast biological organisms use up oxygen in a body of water.
biogeochemical cycle
a circuit or pathway by which a chemical element or molecule moves through both biotic ("bio-") and abiotic ("geo-") parts of an ecosystem.
biome
a climatic and geographically defined area of ecologically similar communities of plants, animals, and soil organisms, often referred to as ecosystems.
carbon dioxide
a gas with the chemical formula CO2; the most abundant greenhouse gas emitted from fossil fuels.
cancer
a group of diseases in which cells are aggressive (grow and divide without respect to normal limits), invasive (invade and destroy adjacent tissues), and sometimes metastatic (spread to other locations in the body).
absorption pit (soakaway)
a hole dug in permeable ground and filled with broken stones or granular material and usually covered with earth allowing collected water to soak into the ground.
carbon budget
a measure of carbon inputs and outputs for a particular activity.
biocapacity
a measure of the biological productivity of an area. This may depend on natural conditions or human inputs like farming and forestry practices; the area needed to support the consumption of a defined population.
biological pest control
a method of controlling pests (including insects, mites, weeds and plant diseases) that relies on predation, parasitism, herbivory, or other natural mechanisms.
bioremediation
a process using organisms to remove or neutralise contaminants (e.g. petrol), mostly in soil or water.
best practice
a process, technique, or innovative use of technology, equipment or resources or other measurable factors that have a proven record of success.
carbon pool
a storage reservoir of carbon.
carcinogen
a substance, radionuclide or radiation that is an agent directly involved in the promotion of cancer or in the facilitation of its propagation.
carbon taxes
a surcharge on fossil fuels that aims to reduce carbon dioxide emissions.
circular metabolism
a system in which wastes, especially water and materials, are reused and recycled cf. linear metabolism.
carbon labelling - use of product labels that display greenhouse emissions associated with goods (www.carbo
abel.co.uk for product carbon footprint methodology).
biocoenosis (alternatively, biocoenose or biocenose )
all the interacting organisms living together in a specific habitat (or biotope).
C3 & C4 plants - C4 plants comprise about 5% of all plants, are most abundant in hot and arid conditions, and include crops like sugar cane and soybeans. During photosynthesis they form molecules with
arbon atoms and saturate at the given level of CO2. C3 plants, the other 95%, photosynthesise to form 3 carbon molecules and increase photosynthesis with as CO2 levels increase.
affluenza
as defined in the book of the same name[1] 1. the bloated, sluggish and unfulfilled feeling that results from efforts to keep up with the Joneses. 2. an epidemic of stress, overwork, waste and indebtedness caused by dogged pursuit of the Australian dream. 3. an unsustainable addiction to economic growth. The traditional Western environmentally unfriendly high consumption life-style: a play on the words affluence and influenza cf. froogle, freegan.
biodegradable
capable of being decomposed through the action of organisms, especially bacteria.
CFC
chloroflorocarbon. CFCs are potent greenhouse gases which are not regulated by the Kyoto Protocol since they are covered by the Montreal Protocol.
adaptive radiation
closely related species that look very different, as a result of having adapted to widely different ecological niches.
bluewater
collectible water from rainfall; the water that falls on roofs and hard surfaces usually flowing into rivers and the sea and recharging the ground water. In nature the global average proportion of total rainfall that is blue water is about 40%. Blue water productivity in the garden can be increased by improving irrigation techniques, soil water storage, moderating the climate, using garden design and water-conserving plantings; also safe use of grey water.
alloy
composite blend of materials made under special conditions. Metal alloys like brass and bronze are well known but there are also many plastic alloys.
broa
cre farm - commercial farm covering a large area; usually a mixed farm in dryland conditions.
alternative fuels
fuels like ethanol and compressed natural gas that produce fewer emissions than the traditional fossil fuels.
atmosphere
general name for the layer of gases around a material body; the Earth's atmosphere consists, from the ground up, of the troposphere (which includes the planetary boundary layer or peplosphere, the lowest layer), stratosphere, mesosphere, ionosphere (or thermosphere), exosphere and magnetosphere.
carbon neutral
generally refers to activities where net carbon inputs and outputs are the same. For example, assuming a constant amount of vegetation on the planet, in the short term burning wood will add carbon to the atmosphere but this carbon will cycle back into new plant growth.
car pooling
giving people lifts to help reduce emissions and traffic.
blackwater
household wastewater that contains solid waste i.e. toilet discharge.
biologically productive land
is land that is fertile enough to support forests, agriculture and / or animal life. All of the biologically productive land of a country comprises its biological capacity. Arable land is typically the most productive area.
arable land
land that can be used for growing crops.
biogas
landfill gas and sewage gas, also called biomass gas.
anthropogenic
man-made, not natural.
backflow
movement of water back to source e.g. contaminated water in a plumbing system.
chlorofluorocarbons
one of the more widely known family of haloalkanes.
absorption
one substance taking in another, either physically or chemically.
adsorption
one substance taking up another at its surface.
carbon source
opposite of carbon sink; a net source of carbon for the atmosphere.
afforestation
planting new forests on lands that have not been recently forested.
acid rain
rain or other forms of precipitation that is unusually acidic.
albedo
reflectance; refers to the ratio of light from the Sun that is reflected by the Earth's surface, to the light received by it. Unreflected light is converted to infrared radiation (heat), which causes atmospheric warming (see "radiative forcing"). Thus, surfaces with a high albedo, like snow and ice, generally contribute to cooling, whereas surfaces with a low albedo, like forests, generally contribute to warming. Changes in land use that significantly alter the characteristics of land surfaces can alter the albedo.
biotic
relating to, produced by, or caused by living organisms. (see also abiotic).
aerobic
requiring air or oxygen; used in reference to decomposition processes that occur in the presence of oxygen.
carbon credit - a marke
riven way of reducing the impact of greenhouse gas emissions; it allows an agent to benefit financially from an emission reduction. There are two forms of carbon credit, those that are part of national and international trade and those that are purchased by individuals. Internationally, to achieve Kyoto Protocol objectives, 'caps' (limits) on participating country's emissions are established. To meet these limits countries, in turn, set 'caps' (allowances or credits: 1 convertible and transferable credit = 1 metric tonne of CO2-e emissions) for operators. Operators that meet the agreed 'caps' can then sell unused credits to operators who exceed 'caps'. Operators can then choose the most cost-effective way of reducing emissions. Individual carbon credits would operate in a similar way cf. carbon offset.
alien species
see introduced species.
ancient forest
see old growth forest.
chlorinated hydrocarbon
see organochloride
aerosols
solid or liquid particles suspended within the atmosphere.
anthroposophy
spiritual philosophy based on the teachings of Rudolf Steiner (25 February 1861 - 30 March 1925) which postulates the existence of an objective, intellectually comprehensible spiritual world accessible to direct experience through inner development - more specifically through cultivating conscientiously a form of thinking independent of sensory experience. Steiner was the initiator of biodynamic gardening.
available water capacity
that proportion of soil water that can be readily absorbed by plant roots.
bioaccumulation
the accumulation of a substance, such as a toxic chemical, in the tissues of a living organism.
Carbon Dioxide Equivalent (CO2e )
the unit used to measure the impacts of releasing (or avoiding the release of) the seven different greenhouse gases; it is obtained by multiplying the mass of the greenhouse gas by its global warming potential. For example, this would be 21 for methane and 310 for nitrous oxide.
biodiversity
the variety of life in all its forms, levels and combinations; includes ecosystem diversity, species diversity, and genetic diversity.
biosphere
the zone of air, land and water at the surface of the earth that is occupied by living organisms; the combination of all ecosystems on Earth and maintained by the energy of the Sun; the interface between the hydrosphere, geosphere and atmosphere.
bioenergy
used in different senses: in its most narrow sense it is a synonym for biofuel, fuel derived from biological sources. In its broader sense it encompasses also biomass, the biological material used as a biofuel, as well as the social, economic, scientific and technical fields associated with using biological sources for energy.
capillary action (wicking)
water drawn through a medium by surface tension.