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Glossary of Terms

(from Wikipedia.com 2010 and MSN Encata 2010)


Keyword Description
Adaptation  The evolutionary process whereby a population becomes better suited to its habitat.
Amphibian  Animals such as frogs, toads, salamanders, newts, and caecilians, are ectothermic (or cold-blooded) animals that metamorphose from a juvenile water-breathing form, either to an adult air-breathing form, or to a paedomorph that retains some juvenile characteristics.
Aquatic vegetation  Plants that have adapted to living in or on aquatic environments. Because living on or under water requires numerous special adaptations, aquatic plants can only grow in water or permanently saturated soil.
Aquifer  An underground layer of water-bearing permeable rock or unconsolidated materials (gravel, sand, silt, or clay).
Bank  The shoreline of a body of water. The grade (slope) can vary from vertical to a shallow slope.
Boom spray irrigation  
Low application rate irrigation system permanently placed in a field including two upwardly bowed wings supported by guy wires and rotated about a vertical axis. The boom is rotated by water being discharged in opposite directions from spray nozzles on the two wings aided by wind engaging flaps pivotally supported by each wing.
Cap on (water) extraction  A mandated limit on the amount of water that can be removed from a river system.
Canopy  Refers to the upper layer or habitat zone, formed by mature tree crowns and including other biological organisms.
Carnivore  An organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of animal tissue, whether through predation or scavenging.
Carrion  Refers to the carcass of a dead animal.
Cascade  A small waterfall or series of waterfalls.
Catchment  An extent or area of land where water from rain and melting snow or ice drains downhill into a body of water, such as a river, lake, reservoir, estuary, wetland, sea or ocean. The drainage basin includes both the streams and rivers that convey the water as well as the land surfaces from which water drains into those channels, and is separated from adjacent basins by a drainage divide.
Character  One of the people portrayed in a book, play, or movie.
Clarity  The quality of water - being clear, pure, or transparent.
Cold water pollution  Releases of unnaturally cold water from the base of reservoirs which change the fish and macroinvertebrate fauna of rivers, and reduce river productivity.
Collage  A work of formal art, primarily in the visual arts, made from an assemblage of different forms, thus creating a new whole.
Colour  The visual perceptual property corresponding in humans to the categories called red, green, blue and others. Colour derives from the spectrum of light interacting in the eye with the spectral sensitivities of the light receptors. Colour categories and physical specifications of colour are also associated with objects, materials, light sources, etc., based on their physical properties such as light absorption, reflection, or emission spectra.
Community  Group of interacting organisms (or different species) sharing an environment.
Competition A contest between individuals, groups, nations, animals, etc. for territory, a niche, or a location of resources. It arises whenever two or more parties strive for a goal which cannot be shared.  Competition is the driving force behind evolution and natural selection; the competition for resources such as food, water, territory, and sunlight results in the ultimate survival and dominance of the variant of the species best suited for survival. This is also present between species. A limited amount of resources are available, and several species may depend on these resources. Thus, each of the species competes with the others to gain access to the resources. As a result, species less suited to compete for the resources must either adapt or die out.
Commercial land use  Land designated for the use of commerce.
Composition  The placement or arrangement of visual elements or ingredients in a work of art, as distinct from the subject of a work. It can also be thought of as the organisation of the elements of art according to the principles of art.
Confining layer Layer of impermeable material that contains groundwater above or below its’ level.
Constructed wetland  An artificial marsh or swamp, created for anthropogenic discharge such as wastewater, stormwater runoff or sewage treatment, and as habitat for wildlife, or for land reclamation after mining or other disturbance. Natural wetlands act as biofilters, removing sediments and pollutants such as heavy metals from the water, and constructed wetlands can be designed to emulate these features.
Coppicing  A traditional method of woodland management which takes advantage of the fact that many trees reshoot from the stump or roots if cut down.
Crop  A group of plants grown by people for food or other use, especially on a large scale in farming or horticulture.
Crown  The branches, leaves, and reproductive structures extending from the trunk or main stems of a woody plant.
Defoliation  The loss of leaves on a plant.
Delta formation
The formation of a river basin at the mouth of the river is usually characterised by the shape of a delta, the triangular Greek letter.
Design elements  Describes fundamental ideas about the practice of good visual design that are assumed to be the basis of all intentional visual design strategies.
Detritus  Non-living particulate organic material. It typically includes the bodies or fragments of dead organisms as well as faecal material.
Dialogue 
The words spoken by characters in a book, movie, or play, or a section of a work that contains spoken words.  
Ditch irrigation  An artificial application of water to the soil through a series of low earthern culverts. It is used to assist in the growing of agricultural crops, maintenance of landscapes, and revegetation of disturbed soils in dry areas and during periods of inadequate rainfall.
Displace  To move something from its usual or correct place.
Distribution  The range of a species is the geographical area within which that species can be found.
Dominant species  The degree to which different species in an ecological community predominate. In most communities, one or a few species are most numerous, or form the bulk of the biomass – these are the dominant species. Most ecological communities are defined by their dominant species.
Drip irrigation Also known as trickle irrigation or microirrigation, is an irrigation method which saves water and fertiliser by allowing water to drip slowly to the roots of plants, either onto the soil surface or directly onto the root zone, through a network of valves, pipes, tubing, and emitters.
Drought  An extended period of months or years when a region notes a deficiency in its water supply. Generally, this occurs when a region receives consistently below average precipitation (rainfall). It can have a substantial impact on the ecosystem and agriculture of the affected region.
Ecosystem  Consists of all the organisms living in a particular area, as well as all the non-living, physical components of the environment with which the organisms interact, such as air, soil, water, and sunlight.
Electrical conductivity  Measure of a material’s ability to conduct an electric current. This is generally used as an indicator of salt in an aquatic ecosystem as salty water is more conductive than fresh water.
Elements 
A separate identifiable part of something, or a distinct group within a larger group.
Endangered  Population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters.
Endemic  Exclusively native to a place or biota.
Energy pyramid  Graphical representation designed to show the biomass or productivity at each trophic level in a given ecosystem.
Environment  All living and non-living things occurring naturally on Earth or some region thereof.
Environmental flows  The amount of water needed in a watercourse to maintain healthy ecosystems. 
Epicormic Growth  A shoot growing from an epicormic bud from underneath the bark of a stem or branch of a plant. Epicormic buds lie dormant beneath the bark, their growth suppressed by hormones from active shoots higher up the plant. Under certain conditions they develop into active shoots, such as when damage occurs to higher parts of the plant, or light levels are increased following removal of nearby plants. Epicormic shoots occur in many woody species, but are absent from many others, such as most conifers.
Epilimnion  The top-most layer in a thermally stratified lake, occurring above the deeper hypolimnion. It is warmer and typically has a higher pH and dissolved oxygen concentration than the hypolimnion. Being exposed at the surface, it typically becomes turbulently mixed as a result of surface wind-mixing. It is also free to exchange dissolved gases (ie O2 and CO2) with the atmosphere. Because this layer receives the most light it contains the most phytoplankton.
Erosion  The process of weathering and transport of solids (sediment, soil, rock and other particles) and the depositing of them elsewhere.
Exotic  An introduced, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its native distributional range, which has arrived there by human activity, either deliberate or accidental.
Extinct  A species in which there are no surviving individuals that are able to reproduce and create a new generation.
Extraction 
Refers to the practice of locating, acquiring and selling any resource, but typically a natural resource.
Fibre  A fine thread of a natural or synthetic material that can be spun into yarn.
Fish ladder  A structure on or around artificial barriers to facilitate fish migration. Most fishways enable fish to pass around the barriers by swimming and leaping up a series of relatively low steps (hence the term ladder) into the waters on the other side. The velocity of water falling over the steps has to be great enough to attract the fish to the ladder, but it cannot be so great that it washes fish back downstream or exhausts them to the point of being unable to continue their journey upriver.
Fishway  See above. 
Floodplain 
Flat or nearly flat land adjacent to a stream or river that experiences occasional or periodic flooding.
Floor  The layer of organic matter on the ground in a forest.
Focal point  An object of concentrated or immediate attention.
Food chain/web  Representations of the predator-prey relationships between species within an ecosystem or habitat.
Form  The shape or structure of a thing that gives it its distinctive character, considered apart from its content, colour, texture, or composition.
Fragmentation  Describes the emergence of discontinuities (fragmentation) in an organism’s preferred environment. Habitat fragmentation can be caused by geological processes that slowly alter the layout of the physical environment or by human activity such as land conversion, which can alter the environment on a much faster time scale.
Free rider problem 
In economics, collective bargaining, psychology, and political science, “free riders” are those who consume more than their fair share of a public resource, or shoulder less than a fair share of the costs of its production. Free riding is usually considered to be an economic “problem” only when it leads to the non-production or under-production of a public good, or when it leads to the excessive use of a common property resource. The free rider problem is the question of how to limit free riding (or its negative effects) in these situations.
Gill  An anatomical structure found in many aquatic organisms. It is a respiratory organ that extracts dissolved oxygen from water, afterward excreting carbon dioxide.
Glide  A stretch of calm, slowly flowing water in a river or large stream.
Gorge  A deep narrow, usually rocky, valley.
Grazing  A type of predation in which a herbivore feeds on plants (such as grasses). Grazing differs from true predation because the organism being eaten is not killed, and it differs from parasitism as the two organisms do not live together, nor is the grazer necessarily so limited in what it can eat. For terrestrial animals grazing is normally distinguished from browsing in that grazing is eating grass or other low vegetation, and browsing is eating woody twigs and leaves from trees and shrubs.
Gross pollutant trap  Devices trap coarse pollutants in stormwater - notably litter and coarse sediments.
Groundwater  Is water located beneath the ground surface in soil pore spaces and in the fractures of lithologic formations.
Habitat  An ecological or environmental area that is inhabited by a particular species of animal, plant or other type of organism.
Herbivore  Animals that are adapted to eat plants. Herbivory is a form of predation in which an organism consumes principally autotrophs such as plants, algae and photosynthesizing bacteria.
Hypolimnion  The dense, bottom layer of water in a thermally-stratified lake. It is the layer that lies below the thermocline. Typically the hypolimnion is the coldest layer of a lake in summer, and the warmest layer during winter. Being at depth, it is isolated from surface wind-mixing during summer, and usually receives insufficient irradiance (light) for photosynthesis to occur.
Impervious surface 
Mainly artificial structures that are covered by impenetrable materials such as asphalt, concrete, brick and stone and rooftops. Soils compacted by urban development are also highly impervious to water and thus increase stormwater run-off.
Indicator species  Any species that defines a trait or characteristic of the environment. Indicator species can be among the most sensitive species in a region, and sometimes act as an early warning to monitoring biologists.
Industrial landuse  Land designated for industrial use.
Integrated Catchment Management  A subset of environmental planning which approaches sustainable resource management from a catchment perspective, in contrast to a piecemeal approach that artificially separates land management from water management.  Integrated catchment management recognises the existence of ecosystems and their role in supporting flora and fauna, providing services to human societies, and regulating the human environment. Integrated catchment management seeks to take into account complex relationships within those ecosystems: between flora and fauna, between geology and hydrology, between soils and the biosphere, and between the biosphere and the atmosphere. Integrated catchment management recognises the cyclic nature of processes within an ecosystem, and values scientific and technical information for understanding and analysing the natural world.
Introduced species  A species living outside its native distributional range, which has arrived there by human activity, either deliberate or accidental.
Irrigation 
An artificial application of water to the soil. It is used to assist in the growing of agricultural crops, maintenance of landscapes, and revegetation of disturbed soils in dry areas and during periods of inadequate rainfall.
Invader 
A species living outside its native distributional range which is damaging to the ecosystem they are introduced into.
Invasive species  Applies to non-indigenous species, plants or animals that adversely affect the habitats and bioregions they invade economically, environmentally, and/or ecologically.
Invertebrates  An animal without a backbone.
Journaling.
A record with discrete entries, arranged by date, reporting on what has happened over the course of a day or other period. Journals undertaken for institutional purposes play a role in many aspects of human civilisation, including government records, business ledgers and military records or gathering natural history data.
Land use  Human modification of natural environment into built environment such as fields, pastures and settlements.
Large woody debris  Logs, sticks, branches, and other wood that falls into streams and rivers. This debris can influence the flow and the shape of the stream channel. Large woody debris, grains, and the shape of the bed of the stream are the three main providers of flow resistance, and are thus, a major influence on the shape of the stream channel.  Large woody debris is also refrred to as snags and in important refuge habitat for native fish species.
Larvae  Distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle.
Line  The characteristic shape or contour of something.
Macroinvertebrate  An invertebrate that is large enough to be seen without the use of a microscope.
Meandering A twist or bend in something, especially a river, path, or street.
Medicinal plant  Plants that synthesize substances that are useful to the maintenance of health in humans and other animals and are generally used in traditional medications.
Medium  The materials that an artist uses in creating a work.
Microhabitat 
Is often used to describe the small-scale physical requirements of a particular organism or population.
Microirrigation 
An irrigation method which saves water and fertilizer by allowing water to drip slowly to the roots of plants, either onto the soil surface or directly onto the root zone, through a network of valves, pipes, tubing, and emitters.
Migration  The travelling of long distances in search of a new habitat. The trigger for the migration may be local climate, local availability of food, or the season of the year. To be counted as a true migration, and not just a local dispersal, the movement of the animals should be an annual or seasonal occurrence, such as birds migrating elsewhere for the winter, or a major habitat change as part of their life cycle, such as young Atlantic salmon leaving the river of their birth when they have reached a certain size.
Mood  Forms expressing a particular attitude.
Motivation  A reason for doing something or behaving in a particular way.
Mundulla Yellows  Fatal disease that affects eucalypts and other native plants. It was first observed in the vicinity of Mundulla, South Australia in the 1970’s and has now been identified in all States, including Tasmania. It is characterised by progressive yellowing and dieback of foliage. It is not clear whether Mundulla Yellows is caused by living agent(s), or environmental factor(s), or a combination of both.
Narrator  A character in a work of fiction who is presented as telling the story and who refers to himself or herself as “I”.
Native species A species that normally lives and thrives in a particular ecosystem.
Nitrogen  A non-metallic element that occurs as a colourless, odourless, almost inert gas and makes up four-fifths of the Earth’s atmosphere by volume. Used in the manufacture of ammonia, explosives, fertilisers and by plants and animals to make protein.
Non-native species An introduced, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its native distributional range, which has arrived there by human activity, either deliberate or accidental.
Non-point  source pollution  Water pollution affecting a water body from diffuse sources, such as polluted runoff from agricultural areas draining into a river, or wind-borne debris.
Nutrients  Substance that provides nourishment, for example, the minerals that a plant takes from the soil or the constituents in food that keep an organism healthy and help it to grow.
Nymph  The larva of some insects such as mayflies, dragonflies, and grasshoppers that resemble the adult and develops into the adult insect directly, without passing through an intermediate pupa stage.
Over fishing  When fishing activities rise to a level at which fish populations can not be maintained/sustained.
Oxbow 
When rivers meander and are sometimes cut off from their course, they form an oxbow lake which is so named because of the distinctive “U” shape.
Pathogens  Something that can cause disease, for example, a bacterium or a virus.
Perspective  The appearance of objects to an observer allowing for the effect of their distance from the observer.
pH  A measure of acidity or alkalinity in which the pH of pure water is 7, with lower numbers indicating acidity and higher numbers indicating alkalinity.
Photosynthesis  A process by which green plants and other organisms turn carbon dioxide and water into carbohydrates and oxygen, using light energy trapped by chlorophyll.
Platform  A flat raised area of ground on a river bank.
Point source pollution  A single identifiable localised source of air, water, thermal, noise or light pollution.
Pollution  The introduction of contaminants into an environment that causes instability, disorder, harm or discomfort to the ecosystem.  
Pools  A stretch of a river or creek in which the water depth is above average and the stream velocity is quite low.  Such pools can be important for juvenile fish habitat, especially where many stream reaches attain high summer temperatures and very low flow dry season characteristics.
Potamodromous  Fish that migrate on a regular basis in fresh water, on time scales ranging from daily to annual, and over distances ranging from a few meters to thousands of kilometers.
Predation  A biological interaction where a predator (an organism that is hunting) feeds on its prey (the organism that is attacked). Predators may or may not kill their prey prior to feeding on them, but the act of predation always results in the death of its prey and the eventual absorption of the prey’s tissue through consumption.
Primary consumers  Animals adapted to eat plants (i.e. herbivores). Herbivory is a form of predation in which an organism consumes principally autotrophs such as plants, algae and photosynthesizing bacteria.
Producers  An organism that manufactures its own food from simple inorganic substances, for example, a green plant.
Reservoir silting 
The tendency for suspended solids in water to settle out in large less turbulent areas behind reservoir walls, thus over time, filling them in with sediments.
Residential  Relating to, or consisting of, private housing rather than offices or factories.
Resin  A semi-solid substance secreted in the sap of some plants and trees. It is used in varnishes, paints, adhesives, inks, and medicines.
Resnagging 
The process of introducing large woody debris into waterways. This can be natural or human assisted.
Revegetation 
The process of replanting and rebuilding the soil of disturbed land.  This can be natural or human assisted.
Riffles  A shallow stretch of a river or stream, where the current is above the average stream velocity and where the water forms small rippled waves as a result.
Riparian vegetation  An assortment of plants that either are emergent aquatic plants, or herbs, trees and shrubs that thrive in proximity to water.
Riparian zone  The interface between land and a river or stream.  Riparian zones are significant in ecology, environmental management, and civil engineering because of their role in soil conservation, their habitat biodiversity, and the influence they have on fauna and aquatic ecosystems.
River regulation  System of flow attempting to balance the needs of the environment with human uses.
Runs 
An area in a stream or river where water moves quickly and without obstruction along the inner curve of a bend.
Rural landuse  Land that has been designated for rural uses such as agriculture.
Salinity  The saltiness or dissolved salt content of a body of water. It is a general term used to describe the levels of different salts such as sodium chloride, magnesium and calcium sulfates, and bicarbonates.
Sample  A small amount or part of something, used as an example of the character, features, or quality of the whole.
Sandbar  Long ridge of sand formed in a body of water by currents or tides.
Scene  A division of an act of a play or opera, presenting continuous action in one place.
Secondary consumers  An organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of animal tissue, whether through predation or scavenging.
Sediment 
Material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of fluids such as wind, water, or ice, and/or by the force of gravity acting on the particle itself.
Sedimentation  Also called siltation, is the falling out of suspended particles from flowing water resulting in the formation of depositional landforms.  Siltation is a major source of pollution in waterways.
Sense of place 
The awareness that a certain geography’s characteristics make a place special or unique, as well as foster a sense of authentic human attachment and belonging to it.
Sensitivity  Plants or animals capable of registering very slight differences or changes of condition.
Shape  The outline of something’s form.
Snags  Large woody debris lodged in the bottom of a waterbody.
Soil compaction  Occurs when the weight of heavy machinery compresses the soil, causing it to lose pore space. Soil compaction may also occur due to a lack of water in the soil. Affected soils become less able to absorb rainfall, thus increasing runoff and erosion. Plants have difficulty growign in compacted soil because the mineral grains are pressed together, leaving little space for air and water, which are essential for root growth. Burrowing animals also find a hostile environment, because the denser soil is more difficult to penetrate.
Space  A defined area in an artistic work.
Spawning  Pattern of behaviour by which aquatic animals produce and deposit large quantities of eggs in water.
Stratification  The process of layering something, or the state of being layered.
Substrate 
The earthy material that exists in the bottom of an aquatic habitat, like soil, rocks, sand or gravel.
Temperature  The degree of heat as an inherent quality of objects expressed as hotness or coldness relative to something else.
Temperature dependent spawning cue  Level of heat or coldness that prompts fish to undertake reproductive behaviours.
Tertiary consumer  A predator in an ecosystem and/or food chain that feeds on other predators.
Texture  The way in which an artist depicts the quality or appearance of a surface.
Thermal shock  Stress encountered by freshwater fish as a result of thermal discharges into waters.
Thermal stratification  Refers to a change in the temperature at different depths in the lake, and is due to the change in water’s density with temperature.
Thermocline  A thin but distinct layer in a large body of fluid (e.g. water, such as an ocean or lake, or air, such as an atmosphere), in which temperature changes more rapidly with depth than it does in the layers above or below.
Terrace 
Geological term for a step-like landform that borders a shoreline or river floodplain and represents the former position of either a floodplain or the shoreline of a lake, sea, or ocean. A terrace consists of a flat or gently sloping geomorphic surface that is typically bounded on one side by a steeper ascending slope, which is called a “riser” or “scarp”, on one side and a steeper descending slope (riser or scarp) on its other side.
Top predator  Ppredators that have virtually no predators of their own, residing at the top of their food chain. Apex predator species are often at the top of long food chains, where they have a crucial role in maintaining the health of their ecosystems.
Topographic  The features on the surface of an area of land.
Tragedy of the Commons 
Refers to a dilemma described in an influential article by that name written by Garrett Hardin and first published in the journal Science in 1968.  The article describes a situation in which multiple individuals, acting independently, and solely and rationally consulting their own self-interest, will ultimately deplete a shared limited resource even when it is clear that it is not in anyone’s long-term interest for this to happen.
Transect  A strip of ground along which ecological measurements, e.g. of the number of organisms, are made at regular intervals.
Trophic level  A stage in a food chain that reflects the number of times energy has been transferred through feeding, for example, when plants are eaten by animals that are in turn eaten by predators. Plants and plant-eating animals occupy the first two levels, followed by carnivores, usually to a maximum of six levels.
Turbidity  Degree to which particles and sediment are suspended in a liquid.
Turbidity tube  A clear cylindrical tube used to monitor turbidity.
Undercutting 
An area on the bank being eroded at or below the water level which will eventually cause the bank to collapse.
Understorey  A layer of small trees and bushes below the level of the taller trees in a forest.
Urban area
Characterised by higher population density and vast human features in comparison to areas surrounding it.
Vegetation  Plants in general or the mass of plants growing in a particular place.
Vertebrate  An animal with a segmented spinal column and a well-developed brain, for example, a mammal, bird, reptile, amphibian or fish.
Water logging  Refers to the saturation of soil with water. Soil may be regarded as waterlogged when the water table or the groundwater is at or near the surface.
Water quality  The physical, chemical and biological characteristics of water. It is most frequently used by reference to a set of standards against which compliance can be assessed. The most common standards used to assess water quality relate to drinking water, safety of human contact and for the health of ecosystems.
Waterway  Is any navigable body of water. These include rivers, lakes, seas, oceans and canals.
Water sensitive urban design  A term used to describe a land planning and engineering design approach to managing stormwater runoff. WSUD emphasises conservation and use of on-site natural features to protect water quality. This approach implements engineered small-scale hydrologic controls to replicate the pre-development hydrologic regime of watersheds through infiltrating, filtering, storing, evaporating, and detaining runoff close to its source.