A situation (an actual place or any means of contact) in which two or more people agree to buy and sell a product or service. See also market economy. …
The price at which both buyers and sellers of a good or service in a market economy are willing to do business with each other, when supply and demand are equal. Also known as market value . …
Values that can be expressed in financial or monetary terms. …
A mechanism (such as command and control, and environmental regulation) that is designed to influence market forces in order to manipulate market equilibrium, with a view to improving environmental protection or reducing environmental damage. Also known as market‐based incentive . …
An alluvialclay or deposit that contains a relatively large amount of calcium carbonate, and can be used as a fertilizer on soils that are deficient in lime. …
A freshwaterlake in which the concentration of dissolved calcium carbonate is greater than 100 milligrams per litre. …
A type of grass that has an extensive, tightly knit underground root system and can survive in the relatively salty, nutrient‐poor free‐draining sand that is typical of beach dunes. …
A low‐lying wetland habitat with grassy vegetation, often close to a river or lake, that is frequently flooded to a shallow depth. Marshes can be freshwater or saltwater, tidal or non‐tidal. Also known as marshland . …
A US diplomat and classical scholar ( 1801 ? 82 ) who published the influential book Man and Nature in 1864 and is regarded by some as the father of the environmental movement. …
A US conservationist ( 1901 ? 39 ) who founded the Wilderness Society. He was among the first to suggest that large tracts of Alaska be preserved, helped to shape the US Forest Service's policy on wilderness designation and management, and wrote with conviction on all aspects of conservation and preservation. …
A mammal (of the order Marsupialia) which carries its young in a pouch. Examples include opossums, kangaroos, and wombats. …
The economic and political theories of Karl Marx (and Friedrich Engels ), based on the belief that human actions and institutions are driven mainly by economic factors (particularly by a profit motive), that social change is driven mainly by class struggles, and that socialism will ultimately replace capitalism. …
The relative balance between the input and output of material and processes within an open system, such as the snow and ice within a glacier, or the water or sediment moving through a lake or river. …
The deliberate incineration of unsorted solid waste material. …
A catastrophic, widespread event in which a large proportion (up to 90%) of species become extinct in a relatively short time compared with normal background extinction. There have been at least five such mass extinctions, including the wholesale extinction of the dinosaurs, other big reptiles, and many marine invertebrates at the K?T boundary. In the short term mass extinctions have a catastrophi…
A block of the Earth's crust that is bounded by faults and has been moved to create one or more peaks of a mountain range. It is usually more rigid than surrounding rocks. …
A solid mass of rock that is homogeneous, with no joints, cracks, foliation, or bedding. …
The process by which unconsolidated material moves down hillslopes in the form of a flow, slide, fall, or creep, as a result of gravity. Also known as mass wasting . See also avalanche, landslide. …
A method of plant breeding in which seed from a number of individuals is selected to form the next generation, with selection criteria relaxed until later generations and crosses being created at random. …
An instrument that is used to identify and measure the chemicals that are present in a substance by their mass and charge, based on very small samples. See also gas chromatography‐mass spectrometry. …
A form of public transportation in which buses, trains, trams, and other forms of transportation are used to efficiently move large numbers of people, with reduced overall environmental impacts. …
The fruit and seed of shrubs, woody vines, trees, cacti, and other non‐herbaceous vegetation (including acorns, beechnuts, and chestnuts) that is available as food for wildlife. …
In animals, the act of pairing a male and female for sexual reproduction. …
In geology, the small‐grained material that is found in the spaces between larger‐grained materials in a rock. …
A well‐developed soil that normally has a soil profile with clearly defined horizons. …
A stand of trees that is fully grown, especially in height, and is in full seed production. Also known as old growth , or late successional . …
A tree that has reached the desired size or age for its intended use, which varies from species to species. …
1 Part of the life cycle of an organism, when it has become adult, between youth and old age. 2 The middle stage in the cycle of erosion, in which the landscape has high relief and well‐developed drainage. Contrast old age, youth. …
A volcano in Hawaii which is intermittently active and last erupted in 1984 . …
The record of measurements of atmospheric carbon dioxide concentrations which has been collected by scientists at the Mauna Loa Observatory on Mauna Loa in Hawaii, since March 1958 . This is the longest reliable daily record of atmospheric carbon dioxide measurements in the world. …
The period from 1645 to 1715 when solar activity was very low and few sunspots were observed. …
Emissions limitations based on the best demonstrated control technology or practices, taking into account cost and technical feasibility, which produces a very high level of pollution control. …
The highest concentration of a particular pollutant that workers can safely be in contact with in their work environment. …
The highest allowable concentration of a given contaminant in potable water. …
The highest level of exposure to a particular pollutant to which a person may safely be exposed. …
The highest amount of radiation to which a person may safely be exposed.? …
The maximum crop or yield that can be taken on a sustained basis from a particular population in a defined area (such as a portion of the ocean) without driving it towards extinction. Contrast optimum yield. …
The highest dose of a drug, drug combination, or other treatment that an individual of a particular species of animal (including humans) can safely withstand over a major portion of its lifetime. …
US legislation that established a cooperative research programme in forestry for state land‐grant colleges and universities. …
North American pejorative term for a large house built on a small plot of land, often constructed cheaply but including ostentatious traditional features. Also known as starter castle . …
US legislation that authorized a comprehensive research programme for the US Forest Service. This act was repealed and replaced by the Forest and Rangeland Renewable Resources Research Act ( 1978 ). …
A field in which grass or alfalfa are grown to be used as pasture or made into hay. See also hay meadow. …
US economist, co‐author (with Donella Meadows ) of the book Limits to Growth, and member of the Club of Rome. …
The average amount of water that flows down a particular river, per year, expressed either as a depth (in millimetres) of water spread evenly across the entire drainage basin, or as a volume (in cubic metres) of water flowing past a given point. …
The average temperature of the air over a particular location, over the entire year. …
The average temperature of the air over a particular place, over a 24‐hour period. …
A curve or bend in a river channel, which forms naturally by fluvialerosion. See also floodplain, ox‐bow lake. …
The long‐term average height of all low waters at a particular place. …
The long‐term average height of the water level of the sea surface at a particular place. …
The average of mean high water and mean low water. Also known as half‐tide level. …
1 To determine the size of something. 2 A reference point to which other things can be compared. 3 An action that can be taken, for a defined purpose. …
The use of mechanical energy to inject air into water, to cause waste material in the water to absorb oxygen and decompose. …
The use of mechanical means to sort waste material into separate components. …
Any activity that involves the use of mechanical machinery to prepare a site for other uses (including building). …
An approach to thinning trees in a forest which is based on removing an agreed proportion of the trees irrespective of tree size or quality, for example by removing every second tree. See also line thinning, selective thinning. …
Turbulent eddy motions in the air which are caused by physical obstructions, such as trees, buildings, and mountains. …
The process by which frost action, growth of salt crystals, absorption of water, and other physical processes break down rock into smaller fragments, without involving any chemical change. Also known as physical weathering . Contrast chemical weathering. See also weathering. …
A type of moraine that forms in the centre of a glacier or ice stream downstream from the confluence of neighbouring valleys, where adjacent lateral moraines join together. …
The concentration of a particular toxic substance at which 50% of the animals in a test are able to survive for a specified period of exposure. …
An informal, voluntary process for resolving disputes, in which parties are encouraged to discuss issues openly, all decisions are reached by consensus, and any participant can withdraw at any time. …
Any solid waste that results from medical activity, including hospital waste. This includes human pathological wastes, human blood and blood products, used or unused sharps (syringes, needles, and blades), certain animal waste, and other waste that is contaminated with infectious agents or pathogens. …
Something used to prevent or cure illnesses and diseases. …
Whole plants and plant parts (including seeds and fruits) that are used primarily in pharmacy and in making perfumes. …
The period of history between the Fall of the Roman Empire ( ad 300 ) and the Renaissance ( 1450 ) in Europe. Also known as the Middle Ages . …
A climate that has mild, wet winters and warm to hot, dry summers, and is usually located in middle latitudes on the western side of continents. Also known as dry‐summer subtropical climate . …
A substance through which something is transported, such as air or water through which contaminants are distributed. The plural of medium is media. …
A period of time, in environmental terms often defined as between about three and five years. Contrast long term, short term. …
The largest type of urban settlement, with a population of more than 10 million inhabitants, which may contain some open land, and is formed when large conurbations or metropolises grow together and link up. In 1950 there were only two cities in the developing world with populations of more than five million each?Shanghai (China) and Buenos Aires (Argentina). The United Nations estimates that by…
Large planktonic organisms, at least two millimetres in size. …
A unit of electrical power equal to 1000 kilowatts (one million watts). …
Organisms of the benthos which are between 0.1 and 0.5 millimetres in size. Contrast macrobenthos, microbenthos. …
Animals which are between 0.1 and 0.5 millimetres in size. …
Plants which are between 0.1 and 0.5 millimetres in size. …
An Australian shrub (Melaleuca quinquenervia), also known as the tea tree, whose extracted oil has antiseptic and healing properties. It has invaded wetlands of south Florida, displacing native species, reducing the quality of the wildlife habitat, and changing local hydrology, soils, and fire regimes. …
The substance that gives colour to the skin, hair, and parts of the eye, and protects against the damaging effects of ultraviolet radiation. …
The process by which a species adapts to changing environmental conditions by producing more melanin in the skin for increased coloration in the body. See also industrial melanism. …
The most serious form of cancer of the skin, which is highly malignant. …
In a nuclear reactor, a situation in which uncontrolled nuclear chain reactions cause the core to melt. …
The temperature at which a substance changes from a solid to a liquid state, by melting. …
Water that is produced by the melting ice of a glacier or a snowbank. …
A channel that is eroded by glacial meltwater, either under the glacier or along its side. Also known as overflow channel . …
A Brazilian rubber tapper, trade unionist, and environmental activist ( 1944 ? 88 ) whose full name was Francisco Alves Mendes Filho. He fought to stop the logging of the Amazon rainforest to create land for cattle ranching, founded a national union of rubber tappers to try to preserve their profession and the rainforest that it relied upon, and was murdered in 1988 by ranchers opposed to hi…
A scale that is widely used to describe the intensity of earthquakes. See also modified mercalli intensity scale. Compare Richter scale. The scale is given in Appendix 7. …
A projection of the Earth onto a cylinder, in order to produce a flat map, in which areas appear greater the farther they are from the equator. It is the most commonly used map projection in atlases. …
Commercially valuable timber, which can be sold at profit. …
A type of barometer used for measuring atmospheric pressure in which mercury rises or falls in a graduated glass tube as the pressure of the atmosphere increases or decreases. …
A naturally occurring element which is present in various ores. It is a toxic heavy metal which is liquid at room temperature. Mercury is used as an industrial chemical in a range of processes (such as the production of chlorine), and in instruments such as thermometers and barometers. It does not biodegrade naturally in the environment, and once released remains indefinitely but can be biotransfo…
A toxic condition in humans that is caused by swallowing or inhaling mercury, and can cause vomiting and diarrhoea and kidney problems that may lead to death. See also Minamata disease. …
A north?south line between the North Pole and the South Pole, at right angles to the equator, which connects all places with a given longitude. …
Along a meridian or line of longitude. Contrast zonal. …
A permanently stratified lake in which complete mixing of the water does not naturally occur. …
Organisms that spend part of their time as plankton but also spend some time as benthos, such as planktonic larvae of benthic invertebrates. …
A broad, flat‐topped hill surrounded by cliffs, capped with a protective layer of resistant rock, common in semi‐arid areas. …
A type of prairie that is found on relatively well drained sites which have high moisture available through most of the growing season. …
The climate of an area up to several square kilometres in area; larger than a microclimate but smaller than a macroclimate. …
The deep rotating column of air within a supercell thunderstorm. …
Small animals, such as worms and insects, which are bigger than microfauna but smaller than macrofauna. …
Small plants, which are bigger than microflora but smaller than macroflora. …
Brackish water with a salinity of between 5 and 18 parts per thousand (?). …
The middle Stone Age, following the Palaeolithic, which began in Europe about 8500 BC, during which cultures were reliant on hunting, fishing, and gathering. …
The upper boundary of the mesosphere with the thermosphere, at a height of about 80 kilometres above the ground. …
The zone of oceans and seas between about 200 and 1000 metres below the surface, between the upper sunlit (photic) zone above and the dark ocean depths below, where some light can still penetrate to allow limited photosynthesis. …
A plant that is adapted to grow in fairly moist conditions. Contrast hydrophyte, xerophyte. …
The study of weather systems that range in size from a few kilometres to about 100 kilometres in scale. This includes local winds, squall lines, thunderstorms, and tornadoes. Contrast synoptic meteorology. See also meso‐. …
1 The layer within the upper atmosphere that lies above the stratosphere, stretching from about 50 kilometres to the mesopause (about 80 kilometres above the ground), in which temperature decreases quite sharply with height down to about -90?C. 2 The lower mantle within the Earth's crust. …
A moderately productive habitat (such as a lake or reservoir) that has a moderate supply of nutrients. Contrast oligotrophic, eutrophic. See also eutrophication. …
The era of geological time after the Palaeozoic era and before the Cenozoic era, about 245 to 65 million years ago, when there is evidence of the first mammals, birds, and flowering plants. …
A small, thorny hardwood tree that is found in arid parts of North America. …
The chemical changes that occur in a living animal or plant as a result of metabolism. In animals, this includes synthetic reactions (such as the manufacture of proteins and fats) and destructive reactions (such as the breakdown of sugars into carbon dioxide and water). In plants, it includes photosynthesis. …
A process that is used to deliberately modify organisms so they will produce small molecules and chemicals, or biochemicals. …
The rate of biochemical reactions within an organism, which can be estimated by measuring food consumption, energy released as heat, or oxygen used in metabolic activity. …
The biochemical processes through which a living cell or organism converts food to energy and then gets rid of waste products, thus allowing it to continue to function and grow. This involves two sets of processes: catabolism (the breakdown of complex substances into simple ones, which releases energy) and anabolism (the building up of complex substances from simpler ones, with involves absorption…
A product of metabolism, including intermediate and waste products, or something which takes part in the reactions. …
A dense, opaque element that is usually a lustrous solid and is a good conductor of heat or electricity. Eighty per cent of the known elements are metals. Examples include iron, lead, copper, aluminium, silver, and gold. …
The middle layer of a thermally stratifiedlake or reservoir, between the epilimnion (above) and the hypolimnion (below), in which temperature decreases rapidly with depth. Also known as thermocline . …
Any rock that has been altered by metamorphism, involving heating and pressure. Also known as tertiary rock because metamorphic rock is derived from primary igneous rocks and secondary sedimentary rocks. …
Changes in the composition and texture of rock which are caused by pressure, heat, and chemical reactions beneath the surface of the Earth, and result in a more compact and more highly crystalline rock. See also contact metamorphism, regional metamorphism. …
1 In general, a major change in appearance or character. 2 In biology, a stage in the life cycle of certain animals during which the larva rapidly transforms into an adult, such as from a tadpole to a frog or from a caterpillar to a butterfly. See also hypermetamorphosis. …
A set of partially isolated populations that belong to the same species, between which individuals can freely migrate. …
An extraterrestrial mass which has reached the Earth's atmosphere from outer space and is heated to glowing hot by friction as it passes through the atmosphere. A meteor that reaches the Earth's surface is a meteorite. …
A satellite remote sensing system launched in 1998 which monitors the distribution and concentration of aerosols and chemical compounds in the atmosphere. …
An extraterrestrial mass which has reached the Earth from outer space, without burning up in the atmosphere. See also meteor. …
The study of the Earth's atmosphere and of the weather of the lower atmosphere (below about 100 kilometres). …
A geostationary weather satellite launched by the European Space Agency (ESA) and now operated by Eumetsat , that is positioned over Africa and Europe and provides weather imaging of the Earth at both visible light and infrared wavelengths. …
A colourless, non‐poisonous, flammable hydrocarbon gas created by anaerobicdecomposition of organic compounds. It is the main component of natural gas and can be used as a fuel. The main sources of methane are landfills, coal mines, rice paddy fields, natural gas systems, and livestock (such as cows and sheep). It is a greenhouse gas with a global warming potential of 23. Concentrations of metha…
The capture and reuse of methaneemissions (particularly from animal wastes, landfill sites, and coal mines) in order to reduce the greenhouse effect and decrease global warming. …
A colourless, nearly odourless, volatile liquid alcoholfuel that is produced mainly from natural gas and is used as an alternative fuel or biofuel, and as a fuel additive. …
A type of insecticide which works by accelerating the moulting process. …
A poisonous gas or liquid that contains carbon, hydrogen, and bromine, and is used as an effective pesticide. The bromine is an ozone depleter which is harmful to the stratospheric ozone layer. …
An industrial chemical that contains carbon, hydrogen, and chlorine, and is used as a solvent, aerosol propellant, pesticide, and degreasing agent. It is a greenhouse gas and ozone depleter and production of it is now banned under the Montreal Protocol. …
A persistent and particularly toxicgas which attacks many different organs in the human body. It is the gas that killed and injured many people in the Bhopal accident. …
The largest town or city in a region or country, which dominates its economic and cultural life. …
A group of silicateminerals that contain varying amounts of aluminium, potassium, magnesium, iron, and water, and that split into thin, tough, smooth plates. They are common constituents of igneous and metamorphic rocks. See also vermiculite. …
The smaller organisms of the benthos, generally shorter than 0.1 millimetres. Contrast macrobenthos, meiobenthos. …
Contamination of a medium (such as a waterbody) by pathogenicmicro‐organisms. See also biological contaminant. …
The natural processes by which micro‐organisms break down and use a substance. …
The activity and growth of micro‐organisms such as bacteria, algae, diatoms, plankton, and fungi. …
A micro‐organism that is used to kill a particular pest, to which it is toxic, but which poses little health risk to humans. …
A small scale downburst of wind in the atmosphere, which usually lasts for 2?5 minutes and has a radius of less than 4 kilometres. Contrast macroburst. …
The climate of a small area (such as a building, city, or valley) that may be different from that in the surrounding area (mesoclimate) or region (macroclimate). …
A miniature model (such as a laboratory test) that is representative of a larger object (such as the natural environment). …
The study and analysis of the individual parts of the market economy (such as companies or households), particularly in terms of the market process and how it works. Contrast macroeconomics. …
Evolutionary changes on the small scale, such as changes in gene frequencies within a population in response to changing local environmental conditions. Contrast macroevolution. See also adaptation, evolution, natural selection. …
Animals (less than 0.1 millimetres long) that are invisible to naked eye and are visible only through a microscope; for example protozoa and nematodes. Contrast macrofauna, mesofauna. …
Small plants that are invisible to the naked eye and can be seen only through a microscope. Contrast macroflora, mesoflora. …
The immediate environment in which an organism lives, where factors such as moisture and light may be different from those in the surrounding area. Also known as microenvironment or microsite . …
Any invertebrate organism that is too small to be seen with the naked eye (with a body length of less than 1 millimetre). Contrast macroinvertebrate. …
The detailed study of weather at a particular location, over an area up to 2 kilometres wide. …
A unit of length equal to one millionth (10-6) of a metre. Also known as micrometre . …
A nutrient or chemical element that is required for plant growth, but only in relatively small quantities. Examples include iron, zinc, and copper. Also known as microelement or trace element . Contrast macronutrient. …
The use of biotechnology to grow large numbers of plants from very small pieces of plants, including single cells, tissues, and seeds by in vitro methods. …
Small‐scale variations in the ground surface within a particular area. Also known as microtopography . …
Too small (usually smaller than about 1 millimetre) to be seen by the naked eye. Contrast macroscopic. …
A weak more or less continuous vibration of the ground that is strong enough to be detected by seismographs, and which is caused by waves, wind, or human activity, not by an earthquake. …
Important primary pathogens of arthropods, the smallest of the eukaryotes, closely related to fungi. …
Electromagnetic radiation which has a longer wavelength (1 to 35 GHz within the electromagnetic spectrum) than visible light, and is used in radar (longer waves) and in cooking (shorter waves). A type of radiant energy. …
Any living organism (including bacteria, viruses, protozoa, and some types of fungus and algae) that is too small to be seen by the naked eye, and is only visible through a microscope. Also known as microbe . …
The part of the scenery or landscape that is mid‐distance away from the viewer, further than the foreground but closer than the background. …
General term for the illegal disposal of hazardous wastes in remote locations, often at night. …
The water that lies below the surface but above the bottom of a waterbody. …
An important sea‐floor spreading zone in the Atlantic Ocean that drives the lateral movement of crustal plates. See also mid‐ocean ridge, plate tectonics. …
The region of the world that lies between 30? and 50? latitude. Also known as middle latitudes . …
The main climate zones within the mid‐latitudes are the mediterranean, marine west coast, humid subtropical, humid continental, and the mid‐latitude steppe and desert. …
A mid‐latitudeclimate zone that is found in continental interiors, further from the coast than the humid continental and humid subtropical climates, and often cut off from maritime air masses by mountain ranges. The climate is drier (particularly in winter) than in the tropics, and temperatures vary more throughout the year (temperatures below freezing are not uncommon in winter). …
An extensive mountain chain that can rise thousands of metres above the surrounding ocean floor, created by the rise of magma along submarine constructive plate boundaries, resulting in sea‐floor spreading. The ridges are part of a continuous system which runs for 60?000 kilometres through all the oceans, and includes the Mid‐Atlantic Ridge. See also plate tectonics. …
Planning over a period of between about 10 and 25 years into the future, which is intermediate between short‐range planning and long‐range planning. Also known as middle term planning or mid‐term planning . …
A rock that contains both igneous and metamorphic materials, that was formed under immense heat and pressure, and often contains large mineral crystals. …
To move from one place to another and settle there, permanently, periodically or seasonally. …
1 The movement of people or animals, including immigration, emigration, net migration, internal migration, and international migration. 2 The stage in vegetation succession at which the first plant seeds arrive on bare ground. …
Any of the routes along which a contaminant may move through the environment, for example through soil, in groundwater, in surface water, and through the air. …
The seasonal movement (migration) of people, animals, birds or fish from one region to another. …
In North America, a nature reserve designed and set aside for the protection of migratory birds. …
The cyclical changes in the orbit of the Earth around the Sun which are believed to cause long‐term changes in the Earth's climate, according to the Milankovitch theory. These are determined by variations in the elliptical shape of the Earth's orbit around the Sun (over a 95?000‐year cycle), variations in the tilt of the Earth's axis of rotation (over a 42?000‐year cycle), and variations in …
The theory, put forward by Yugoslav astronomer Milutin Milankovitch , that long‐term changes in the Earth's climate are caused by variations in the amount of solar radiation that is received at the Earth's surface, which are due to cyclical changes in the relationship between the Earth and the Sun. See also Milankovitch cycle. …
1 Machinery (such as rotating millstones) that grinds grain into flour or meal. 2 A building that contains such machinery. …
A unit of atmospheric pressure that is equal to a thousandth of a bar. Normal pressure at the Earth's surface is about 1013?mb. …
One of a pair of heavy, flat, disc‐shaped stones that are rotated against one another to grind grain in a mill, or used separately for sharpening steel blades …
Coarse‐grained sedimentary rock, often comprising sandstones, grits, and conglomerates with alternate shales, that can be used for making millstones. …
The similarity (for example in appearance) of two species, for evolutionary advantage. See also Batesian mimicry, M?llerian mimicry. …
A crippling form of mercury poisoning which was first detected among people who ate fish from the mercury‐contaminated waters of Minamata Bay off Japan in the 1950s. …
The second phase of glaciation in Europe during the Pleistoceneice age, equivalent to the Kansan in North America. …
An underground excavation from which mineral or rock is extracted. See also mining, quarry. …
Any water that is released from a mining operation. See also acid mine drainage. …
The return of land to another use, often to the original pre‐mining use, after mining activities have ceased. …
A solid, naturally occurring, inorganic substance (such as copper) with a definite chemical composition, a specific internal crystal structure, and characteristic physical properties. See also common variety mineral. …
1 The breakdown of organic compounds to their inorganic forms (for example, proteins to nitrates and phosphates), as a result of microbialdecomposition. 2 In fossil formation, the replacement of organic parts by inorganic materials. …
The study of the structure and properties of minerals. …
In general, any oil that is made from minerals. Particularly, a thick, greenish‐brown, flammable liquid that is found underground in permeable organicsedimentary rock, which can be refined to produce a number of valuable products including oil and petrol (gasoline). Also known as crude oil or petroleum . …
Any of the various naturally occurring substances such as coal, mineral oil, metals, natural gas, salt, sand, stone, and water, which are extracted from the Earth's crust and converted into products useful for humans. Mineral resources are normally classified as being either metallic (such as iron and aluminium ores) or non‐metallic (such as fossil fuels, sand, and salt). …
The ownership of all rights to gas, oil, or other minerals as they naturally occur at or below the surface of a particular area of land. …
Any soil that is composed mainly of inorganic material (such as weathered rock, or sand, silt or, clay materials) rather than organic matter. …
Any clastic sediment which is composed of individual mineral particles. They are usually classified according to grain size, such as sand or clay. …
Mining waste from open‐pit mining, rather than from hard rock mining. See also mine tailings. …
The solid waste that is separated and left after raw minerals or ore from hard rock mining have been processed. Also known as mining refuse . Contrast mine spoils. …
In the UK, the minimum amount of water that should be allowed to flow down a particular river in order to meet the requirements of existing lawful uses of the water (for agriculture, industry, water supply, or other purposes) and the requirements of navigation, fisheries, or land drainage. Called minimum flow in the USA. …
An approach to the conservation of soil and water resources in which the crop residue or stubble is left on the surface rather than ploughed under, in order to minimize the number of times that a field is tilled. …
The smallest number of individuals of a species in a particular locality that could reasonably be expected to survive in the long term. …
The removal of minerals (such as coal, gold, or silver) from the ground. See also area mining, auger mining, contour mining, lode mining, open cast mining, pit mining, placer mining, strip mining. …
Solid waste from mining activities, which includes the overburden, mining refuse, and mining spoil. Also known as mining waste . …
The overlying material that is removed during mining in order to gain access to the ore within the mineral material below. …
Any group of people (often defined by race or ethnicity) whose members have significantly less control or power over their own lives than the members of a dominant or majority group have over theirs. …
North American term for developed recreation facilities that are relatively cheap to build and run, and are not heavily used, such as observation sites, playgrounds, fishing sites, trailheads, and minor interpretation sites. Contrast major recreation facility. …
An epoch of geological time during the early Tertiary period, from 23 million to 5 million years ago, during which many modern mammals first appeared. …
An optical illusion in which reflections of distant objects are distorted by atmospheric refraction caused by a layer of hot air. …
