Inherited immunity of an individual to a particular disease. …
The surplus of births over deaths in a population over a given period of time (usually a year), normally calculated as crude birth rate minus crude death rate. …
A previously exotic or foreign species which has become established in a particular ecosystem and is now commonly found within it. …
Landscape that has not been modified by human activities. Contrast cultural landscape. …
Ambient concentrations of chemicals that are present in the environment and have not been influenced by humans. …
An IUCN Management Category (III) for protected areas, designed ?to protect and preserve nationally significant natural features because of their special interest or unique characteristics?. …
In conservation assessment, the extent to which a location and its associated biotopes are unaffected by human activities. …
A process that results from natural forces rather than human activities. …
The restoration of habitat by natural processes (such as flooding or fire), which allows native vegetation to region and inhibits the growth of exotic plants. …
The geographical area over which a species has naturally lived in recent times (since about 5000 years before the present), excluding any changes to that range that result from human activities. Also known as ecological range or geographical range . See also historic range, introduced species, native species. …
The natural regrowth of vegetation (for example the renewal of a forest by natural seeding) without any human interference. …
An area of land that is defined by physical features (such as a surrounding mountain range) and contains similar plant and animal species. Natural regions and ecoregions often overlap, but they are not the same. …
Any feature of the natural environment that is of value in meeting human needs, including renewable resources (such as vegetation, water, soil, and wildlife) and non‐renewable resources (such as oil, natural gas, coal, and iron ore). Also known as environmental resource, intrinsic resource . …
The publication of information about the level of natural resource use, existing stocks of natural resources, and environmental degradation, within a region or country. …
The management of natural resources on a sustainable basis, usually in ways that meet multiple objectives including the conservation of wildlife and ecosystems, and the minimizing of environmental impacts and environmental change. …
A US organization founded in 1970 to protect natural resources. …
All types of land use zoning (such as agricultural zoning, floodplain zoning, and forest use zoning) which restrict the uses that are made of natural resource land, to protect the resource base. …
Those sciences that study the natural environment, including astronomy, biology, chemistry, geology, physics, oceanography, and meteorology. …
The process in which, for a given species, the individual organisms that have the most appropriate adaptations to environmental (including social) change are more successful than other individuals that don't have them. The adapted individuals tend to survive better and produce more offspring; those that are not able to adapt disappear. Over time, natural selection helps species become better adapt…
The natural state and species composition of vegetation in an area, as it is or would be if unmodified by human activities. …
A natural disaster that creates a technological emergency, such as an urban fire that results from seismic motion, or a chemical spill that result from flooding. See also disaster, technological disaster. …
An essay by Ralph Waldo Emerson in 1836 , in which he outlined his views of the links between people and nature. …
The natural physical world including plants, animals, and landscapes, particularly those parts that remain in a primitive state, unchanged by humans. …
A private, international conservation group based in the USA which was established in 1951 , whose mission is ?to preserve plants, animals, and natural communities that represent the diversity of life on earth by protecting the lands and waters they need to survive?. …
The conservation of wildlife, biodiversity, and natural ecosystems, by regulating the human use of ecosystems and natural resources and promoting sustainable development. …
An area of land that is set aside and managed in ways that benefit nature conservation, usually by limiting human access and use. Nature reserves are usually much smaller than National Parks or Biosphere Reserves, and many endangered species of plants and animals are protected inside them. …
A non‐profit conservation organization. It provides the scientific information and tools needed to help guide effective conservation action, partly through an international network of natural heritage programmes which provide information about rare and endangered species and threatened ecosystems. Also known as the Association for Biodiversity Information . …
The study of plants and animals in their natural habitats. …
The distance between each minute of latitude, which is about 1.85 kilometres. There are 60 nautical miles to one degree of latitude. …
Waterways that are deep and wide enough to allow navigation by all or specified vessels. …
A hominid, similar to but distinct from modern humans, that lived in Europe and western Asia between about 150?000 and 30?000 years ago. …
A tide that occurs every 14 to 15 days, coincides with the first and last quarter of the Moon, and has a small tidal range. Contrast spring tide. …
A biogeographical realm that covers most of North America and contains a variety of biomes including tundra, grassland, deciduous forest, coniferous forest, chaparral, and desert. …
Electromagneticradiation with a wavelength from 750 to 2500 nanometres, which is usually created by molecular vibrations. …
The earliest period of glaciation in North America during the Pleistoceneice age, equivalent to the Gunz in Europe. …
A scavenger that feeds on animal carcasses (dead meat) rather than live prey. …
The sweet, sugary liquid that many flowers produce in order to attract the insects that assist pollination. …
The fundamental requirements of people, including basics such as food, clothing, shelter, drinkable water, and breathable air. Wants and desires go beyond the basics, and reflect taste and fashion as well as the need to survive. …
An electrical charge that is created by having more electrons than protons. …
An interaction (feedback) that reduces or dampens the response of a system to change. Contrast positive feedback. …
Aquaticorganisms that swim and can move long distances to feed or breed. Contrast plankton. …
A US politician ( 1916 ? 2005 ) who came up with the idea for Earth Day in 1969 when he was a Senator from Wisconsin. …
A microscopic free‐living worm that has an unsegmented body. Nematodes are commonly found in marine and freshwaterhabitats, in soil, and as parasites of plants and animals. …
The formation of a new species that has evolved relatively recently and is locally distributed, as a result of divergent adaptation of existing species to differing environmental conditions. …
A period of geological time within the Tertiary subera, between about 24 and two million years ago, which comprises the Miocene and Pliocene epochs. …
A series of relatively small glacier advances in the northern hemisphere during the last few thousand years of the Holocene. …
The New Stone Age, following the Mesolithic, which began in the Near East around 8000 bc and in Europe around 6000 bc , and was characterized by the adoption of agriculture, village life, and the use of pottery. …
A natural, colourless, inertgas that comprises 0.0012% of the Earth's atmosphere. When an electric current is discharged through it, neon produces a reddish‐orange glow, and it is used in luminous tube signs and lights. …
The retention of juvenile body characters in the adult state. …
A biogeographical realm that occupies Central and South America, and is dominated by tropical forest, savanna, and desert. …
The tropical parts of the New World (the Americas). See also palaeotropics. …
A branch of economics that studies the allocation of scarce resources between competing uses and users, based on principles of market equilibrium and profit maximization. …
A modern Darwinian theory that explains new species in terms of genetic mutations and natural selection. …
A pessimist view of the relationship between population, economic growth, and resources, based on the ideas of Thomas Malthus , who argued that population growth and economic growth would eventually be checked by absolute limits on resources such as food, energy, or water. This viewpoint grew in popularity particularly between the 1940s and the 1960s, when population growth and economic developm…
A geological interpretation of features of the Earth's surface (including rocks, fossils, and landforms) as the product of one or more major floods, such as Noah's flood as described in the Old Testament of the Bible. Contrast uniformitarianism. See also catastrophism. …
The relatively shallow waters within the ocean over the continental shelf, down to a depth of about 200 metres. This ecological zone is generally richer in nutrients than deep ocean waters. …
See National Emission Standards for Hazardous Air Pollutants. …
A structure in which animals (particularly birds) lay eggs or give birth to their young. …
An artificial box, platform, or other structure that enhances the reproductive habitat for target species. …
The nest‐related activities of adult animals, including nest building, egg laying, and departure of the young from the nest. …
Vegetation (including grasses, low shrubs, and thickets) that protects nesting sites for quail, grouse, and many species of songbirds. …
Gross national product adjusted by subtracting the cost of problems such as pollution and adding the value of beneficial, non‐market activities such as leisure and recreation. …
The total amount of useful energy that is produced during the lifetime of an energy system, minus the energy that is used, lost, or wasted in making the useful energy available. …
The difference between the number of individuals who move in and the number who move out of a country or area within a specified period of time (normally one year). Immigration minus emigration. …
The future stream of benefits and costs associated with a particular project or resource‐using activity, converted into equivalent values today. This is estimated by assigning monetary values to benefits and costs, discounting future benefits and costs using an appropriate discount rate, and subtracting the total discounted costs from the total discounted benefits. NPV is used in cost?benefit an…
The total amount of energy or biomass that is accumulated by plants through photosynthesis in a given area or habitat, over a specified period of time (usually a year). It is calculated from gross primary production minus respiration. …
The amount of organic material that is produced by biological activity in an area or volume, in a given period of time, which is equivalent to gross primary productivity minus the respiration rate. It is conventionally expressed in grams per square metre per year (g m?2 year?1), and varies from ecosystem to ecosystem. The most productive ecosystems are reefs and estuaries, with natural forests and…
The balance between all incoming energy and all outgoing energy carried by both shortwave and longwave radiation. …
The net heating effect on the Earth of the radiative forcing of climate, which can be positive or negative. …
A measure of fertility, based on the number of daughters born to a woman given current birth rates, and her chances of living to the end of her child‐bearing years. …
In greenhouse gas emission control, the idea that all emission sources in the same area that are owned or controlled by a single company can be treated as one large source, so an emission increase at one source can be offset with an emission reduction at another source in the same area. See also bubble. …
Net monetary value; total assets minus total liabilities. …
A toxic substance, such as lead or mercury, that poisons nerve cells. …
An organism that rests or swims on the surface of a water body. …
To decrease the acidity or alkalinity of a substance by adding alkaline or acidic materials, respectively, in order to make it neutral. …
A stable atmospheric condition that exists in dry air when the environmental lapse rate equals the dry adiabatic rate, and in moist air when the environmental lapse rate equals the saturated adiabatic rate. …
A subatomic particle that is found in all atoms except normal hydrogen, and which has no electric charge. See also electron, proton. …
A method of identifying the isotopes of an element by bombarding them with neutrons and observing the radioactive decay products that are emitted. …
The view that humans represent only one among many species on Earth, that human activities are determined by the environment as well as by social and cultural factors, and that humans are strongly dependent upon the environment and its resources. Contrast dominant social paradigm. …
The emergence of a new global political economy in the latter part of the 20th century, in response to powerful economic, political, and technological forces that have transformed the world. It is reflected, for example, in new attitudes towards economic growth and development, international aid, regionalism, multinational corporations, national policies, and sustainable development. …
Countries (such as South Korea, Taiwan, and Singapore) that have undergone major industrialization only in recent decades. …
Any of a series of social movements that have emerged in recent decades (including the environmental movement, the women's movement, and the gay rights movement), which have different origins, strategies, and goals from more traditional social movements based on class and economics. …
A planned urban community that is developed in a rural area, and is designed to be largely self‐sufficient with its own housing, education, commerce, and recreation. …
A planning movement to promote cities and towns with planned growth that minimizes damage to the environment, through the restoration of urban centres and towns, the reconfiguration of sprawling suburbs into communities of neighbourhoods and districts, the conservation of natural environments, and the preservation of the built legacy. …
See National Forest Land and Resource Management Plan. …
The functional role and position of a species within a community or ecosystem, which is defined by such things as what the species does, how it feeds, what and when it eats, when and for how long it is active, how it reproduces, how it behaves, what particular part of the habitat it uses, and how it responds to temperature and moisture. In most ecosystems a number of species could perform a partic…
An overlap in resource requirements by two species in the same habitat or ecosystem. …
The process by which a species becomes better adapted, by natural selection, to the specific characteristics of a particular habitat. …
A silver‐white, hard, malleable, ductilemetal that can be highly polished, is resistant to corrosion, and is widely used in the manufacture of steel. It occurs naturally in all parts of the environment, including plants and animals, is extremely persistent in soils, and is carcinogenic to humans. See also outer core. …
The main active ingredient of tobacco, which is addictive and extremely toxic to humans. It causes irritation of lung tissues, constriction of blood vessels, increased blood pressure and heart rate, and stimulation of the central nervous system. It is also used as an insecticide. …
The time between sunset and sunrise, when it is dark outside. Contrast day. …
Mid‐level or low clouds that form shapeless, thick dark grey cloud layers and often bring rain or snow. …
An independent organization (the Nuclear Industry Radioactive Waste Executive) that was set up in the UK in 1982 to research, develop, and operate radioactive waste disposal facilities on behalf of the nuclear power industry. In 1985 it became a limited company whose mission is ?to provide the UK with safe, environmentally sound and publicly acceptable options for the long‐term management of…
A naturally occurring salt that contains nitrogen and oxygen, can exist in the atmosphere or as a dissolved gas in water, is a nutrient for plants and an inorganic fertilizer, and can cause severe illness in humans and animals. It is produced in septic systems, animal feed lots, agricultural fertilizers, manure, industrial wastewaters, sanitary landfills, and garbage dumps. …
A colourless or yellowish acid that is made by distilling a nitrate with sulphuric acid. It is used especially in the production of fertilizers and explosives and rocket fuels. It is caustic and corrosive, is a component of acid rain, and acute exposure to it can cause irritation to the lungs, nose, throat, and skin. …
A colourless, poisonous gas formed by the oxidation of nitrogen or ammonia. It is the most common form of nitrogen emitted into the atmosphere and is usually produced by fuel combustion. It is converted to nitrogen dioxide in the atmosphere, is a precursor of ozone and nitrate, and is a toxic air pollutant. …
The oxidation of ammonia to nitrite and nitrite to nitrate by micro‐organisms. Contrast denitrification. …
bacteria that convert nitrites into compounds that can be used by green plants to build proteins. Also known as nitrate‐forming bacteria . See also nitrite‐forming bacteria. …
A salt of nitrous acid that is commonly found in soil, is produced by the chemical modification of ammonium by specialized bacteria, and is toxic to plants and animals at high concentrations. The second stage of the nitrification process. …
Bacteria that combine ammonia with oxygen to form nitrites, as part of the nitrification process. …
The processes by which nitrogen circulates in both organic and inorganic phases between the atmosphere and the biosphere. Compared with the other major biogeochemical cycles it is relatively fast but also very complex. The atmosphere is composed mostly of nitrogen gas (N2). This is chemically unreactive, which means that it cannot be used directly by plants. In order to make it available to plants…
A reddish‐brown gas that is produced by combustion, when nitric oxide emitted from power plants and vehicles combines with oxygen in the atmosphere. It is toxic at high concentrations, reacts with moisture in the air to form nitric acid (which is highly corrosive to metals), and in the presence of sunlight and volatile organic compounds it can contribute to the formation of ground‐level ozone,…
A colourless, tasteless, odourless, and relatively unreactive gas that makes up nearly four‐fifths (78% by volume) of the atmosphere. It is a macronutrient, an essential component of proteins and nucleic acids in living organisms, occurs in nature in a variety of forms (ammonia, ammonium, nitrate, nitrite), and is a key ingredient in many commercial fertilizers. Nitrogen availability controls pl…
A chemical process by which nitrogen in the atmosphere is assimilated into organic compounds, by nitrogen‐fixing bacteria and nitrogen‐fixing plants, and made available to other organisms through food chains. …
Any animal or vegetable residues that contain significant amounts of nitrogen. …
Gas compounds of nitrogen and oxygen (nitric oxide, nitrogen dioxide, and nitrous oxide) which are produced directly or indirectly from the combustion of fossil fuels and from processes used in chemical plants. Emissions of nitrogen oxides into the atmosphere combine with oxygen to form nitrogen dioxide, and this in turn reacts with water vapour to form nitric acid, which is an ingredient in acid …
Bacteria that convert nitrogen from the atmosphere or soil into ammonia, which can then be converted into plant nutrients by nitrite‐ and nitrate‐forming bacteria. …
A plant that can assimilate and fix free nitrogen from the atmosphere, through the work of bacteria that live in its root nodules. …
A powerful and persistent greenhouse gas, with a global warming potential of 320. It is naturally created by microbial activity in soils, but it is increased by soil cultivation practices (particularly rice paddies), the use of commercial and organic fertilizers, combustion of fossil fuels, production of nitric acid, and burning of biomass. …
See National Oceanic and Atmospheric Administration. …
A chemically inactive metal (such as gold, silver, or platinum) which is resistant to corrosion or oxidation. Also known as a precious metal . …
A wavy, thin, bluish‐white type of cloud that forms at altitudes of 80?90 kilometres above the surface of the Earth, looks similar to cirrus clouds, and is best seen at twilight at high latitudes. …
A small lump, such as a small rounded lump of mineral substance (for example, chert) which is usually harder than the surrounding rock, or a small growth on the roots of most legumes and some other plants, that plays a part in nitrogen fixation. …
See National Oil and Hazardous Substances Contingency Plan. …
Unwanted or undesirable sound, particularly if it is loud and disturbs people's communication, sleep, study, or recreation. …
Pollution that is caused by noise, for example from heavy traffic, busy factories, or large gatherings of people. …
Species of plant and animal from which threats have declined, so their survival is not currently threatened. …
A person who lives in no fixed place but has a wandering lifestyle, moving about in search of food or grazing land for their animals. …
The practice of living by moving from place to place, having a nomadic lifestyle. Contrast pastoralism, sedentism, transhumance. …
Countries that are not included in Annex I of the United Nations Framework Convention on Climate Change, and that therefore do not currently have binding emission reduction targets. …
Countries that are not included in Annex B of the Kyoto Protocol, and that therefore do not currently have binding emission reduction targets. …
Any contaminant that remains undiluted as a bulk liquid in groundwater, such as spilled liquid petroleum products (like gasoline) that are not mixed into groundwater but float as a layer in the rock above it. …
An area that does not meet ambientair quality standards for a criteria air pollutant. …
Materials (such as glass, heavy metals, and most types of plastics) that cannot be broken down by livings things into simpler chemicals. …
A tree‐felling activity which does not yield a net income, usually because the trees that are cut are too small, are of poor quality, or are not marketable. …
The removal of trees for reasons other than timber production. …
Not obeying all the federal and state regulations that apply. …
A North American term for any coal that emits a relatively large amount of sulphur dioxide (greater than 3.0 pounds per million Btu) when burned. Also known as high sulphur coal . …
The use of resources in ways that do not reduce supply. Examples include hiking, bird watching, and nature study in a forest. Contrast consumptive use. …
The value of natural resources which are not diminished by their use, that do not require the valuer to have access to them or make active use of them. Also known as non‐use value, passive use value, or existence value . Contrast use value. …
Any unharvested wildlife that is valuable for observation, education, enjoyment, and as a natural member of an ecological community. …
A general term for a variety of recreational activities related to wildlife. Primary non‐consumptive uses include general wildlife observation, bird‐watching, bird‐feeding, and wildlife and bird photography. Secondary uses include nature walks, membership of wildlife organizations, ownership of wildlife pets, and visits to zoos. …
Any pollutant (such as asbestos, benzene, mercury, and polychlorinated biphenyls) that is not a criteria pollutant. Also known as non‐conventional pollutant or unconventional pollutant . …
Any metal that isn't iron or an alloy that doesn't contain iron. Examples include aluminium, lead, and copper. …
Land that is not used for forestry or timber production, but is used for other activities such as farming, transport, industry, commerce, and housing. …
A non‐profit group or association that is separate from government, and whose purpose is to pursue particular social objectives (such as environmental protection) or to serve particular constituencies (such as indigenous peoples). Examples include the World Wide Fund for Nature and the Red Cross. …
A soil that has developed mainly under aerobic conditions. …
A form of radiation (for example from microwaves, radio waves, and low‐frequency electromagnetic fields from high‐voltage transmission lines) that does not change the structure of atoms but does heat tissue and may cause harmful biological effects. …
Financial damages that are generated by environmental change (such as climate change), which cannot be evaluated in terms of market failure because of a lack of information and/or an inability to act on the available information. …
Estimated values for goods and services that are not traded for money but are valued in terms of what reasonable people should be willing to pay rather than go without them. Examples include fish and wildlife values and scenic quality values. Contrast market values. See also contingent valuation method. …
Not containing, resembling, or having the properties of a metal. …
Any surface material that will not allow water to penetrate, such as roads and concrete. …
A pesticide which has only short‐lasting harmful effects. Contrast persistent pesticide. …
Scattered sources of pollutants, such as runoff from agriculture, forestry, an urban area, mining, construction, dams, land disposal, and saltwater intrusion. Contrast point source. …
Water that is unsafe or unpalatable to drink because it contains pollutants, contaminants, minerals, or infectious agents. Contrast potable water. …
Energy (such as the fossil fuels: oil, natural gas, and coal) that comes from a natural resource which is not replaced, or is replaced only very slowly, by natural processes. …
A natural resource (such as oil) which cannot be replaced when it is used up. Also known as depletable resource, stock resource . Contrast renewable resource. …
Rock forming minerals that do not contain silicates. …
1 A species that is not intentionally targeted for control by a pesticide or herbicide, but which may suffer damage because of exposure to it. 2 That part of a catch (for example of fish) which excludes the target species but includes the bycatch and byproduct. …
A disease (such as cancer and heart disease) that cannot be transmitted by a micro‐organism through human contact. …
That part of the biosphere that is affected by human activities. …
An approach to management that involves erring on the side of caution and planning well in advance. See also precautionary principle. …
1 Normal, average, or most common. 2 An expected standard of behaviour and belief that is established and enforced by a group. …
The simplest type of vertical displacement fault, in which one side falls relative to the other. The higher side survives as a cliff‐like escarpment. Normal faults can develop from either compression pressure or from tension pressure. …
The half of the Earth that lies north of the equator. Contrast southern hemisphere. …
A threatened species of owl ( Strix occidentalis caurina ) which is nocturnal, feeds on small mammals and birds, and lives in old growth forests of northern California and the Pacific Northwest of the USA and in southern parts of British Columbia, Canada. Its survival is under threat from the loss of old growth forest habitat, as a result of logging and forest fragmentation, but also as a result o…
General term that is used to describe the industrialized countries which are located mainly in the northern hemisphere and are sometimes referred to as the First World. This includes Canada, the USA, Western European countries, the former Soviet Union, Japan, Australia, and New Zealand. Contrast south. …
The most northerly point on Earth, at a latitude of 90?N in the northern hemisphere; the northern end of the Earth's rotational axis. Contrast south pole. …
The gap, particularly in financial well‐being, between richer developed countries and poorer developing countries. The term is also used to describe socio‐economic differences between northern and southern England. …
A general term for a species that has been evaluated and found not to be at risk of becoming extinct or extirpated. …
A formal notice, published in the US federal register, of intent to prepare an environmental impact statement on a proposed action. …
The process of official designation of a protected area, such as the notification of a Site of Special Scientific Interest in the UK. …
Planting a crop without preparing the ground in advance or working it afterwards. Also known as zero till . …
The belief that certain types of hazardous activities and substances may be needed or acceptable, but not round here. See also lulu. …
A category for species under threat, developed as IUCN Conservation (Red Data Book) Categories, and widely used around the world. The only category within this group is safe. …
A short‐term weatherforecast, generally looking ahead six hours or less. …
Irritating, unpleasant, or harmful to living organisms. …
Plant species that can be harmful or even fatal when eaten by animals. …
The exposure level at which no statistically or biological significant differences in the frequency or severity of any effect can be detected between an exposed and a control population. …
An approach to environmental policy that is based on the idea that the problem of global climate change is linked to other critically important problems of environment and development, the combined risks of which are serious enough, and the eventual benefits of action great enough, to require bold initiatives without delay, even if they impose great immediate cost. …
A special type of nature reserve in which, by law, no one is allowed to fish or collect biological specimens. Rules could apply to one or all species. …
Nitrogen, phosphorus, and potassium, which are common ingredients in commercial fertilizers. …
Energy or power that is produced by nuclear reactions. Nuclear power currently uses only nuclear fission. …
A nuclear reaction process in which isotopes of certain heavy elements (such as uranium and plutonium) are bombarded with neutrons which splits them apart, creates two smaller atoms, and releases a vast amount of energy. Also known as splitting the atom . …
Fuel (such as uranium) that can be used to generate electricity in a nuclear reactor in a nuclear power plant. …
The sequence of processes that are associated with the use of nuclear fuel, from initial mining and milling of the ore, through conversion and enrichment of the nuclear fuel, its use in nuclear power plants, and the management of nuclear waste. …
A nuclear reaction process in which several light nuclei are combined to make a heavier one whose mass is slightly less than the combined mass of the lighter nuclei, which releases energy. This is the reaction that fuels the Sun, where hydrogen nuclei are fused to form helium; it is also one source of power in a nuclear weapon. …
A branch of medicine which uses radioactive substances for the diagnosis and treatment of disease (such as cancer). …
An electric power plant that converts nuclear energy into electrical energy. Heat that is generated by a nuclear reaction is used to make steam, which drives a turbine, which in turn drives an electric generator. …
A change in the composition of a nucleus, caused by bombarding it with atomic or subatomic particles or very high energy radiation (for example in a nuclear reactor). This process can form a new nucleus (nuclear fusion) or split the original nucleus (nuclear fission), and it releases a vast large amount of energy. …
A device in which nuclear fission may be initiated, maintained, and controlled to produce energy, conduct research, or produce fissile material for nuclear explosives. Known in the USA as a nuclear pile. …
Facilities that are associated with the civilian use of nuclear energy, including uranium mills, commercial power reactors, fuel reprocessing plants, and uranium enrichment facilities. …
Military tests of nuclear weapons that are carried out with government approval, in order to improve the design of nuclear weapons and to study the impacts and effects of nuclear explosions. …
Warfare that uses nuclear weapons. See also nuclear winter. …
A device that releases nuclear energy from a nuclear reaction in an explosive manner, in order to damage structures and materials and to kill or injure large numbers of people. A weapon of mass destruction. Also known as a radiological weapon . …
A long period of darkness and extreme cold that scientists predict would follow a full‐scale nuclear war, caused by the blocking out of sunlight by a layer of dust and smoke in the atmosphere, which few organisms could survive. Worst case scenarios predict that nuclear war and nuclear winter would kill most plants and animals in the northern hemisphere and threaten the very survival of the human…
The process by which substances change phase between liquid, gas, and solid, as occurs for example during condensation, deposition, and freezing. …
A biological molecule, composed of a long chain of nucleotides, which controls activities in cells, helps in the synthesis of proteins, and transmits hereditary traits. …
The basis building block of DNA, which consists of a sugar, a phosphate, and an organic base that contains nitrogen. Thousands of nucleotides are linked to form a molecule of DNA or RNA. See also nucleic acid. …
1 The centre of an atom, which is occupied by protons and neutrons. 2 The part of a cell that contains the chromosomes (DNA). 3 A particle (for example of dust or salt) on which water molecules or ice accumulate to form raindrops, snow, hail, and other forms of precipitation. See also cloud condensation nuclei. …
Any species of atom that exists for a measurable length of time, and is defined by the number of protons and neutrons in its nucleus. A nuclide may be radioactive. …
The creation of an area of bare land, either by natural events or by humans, which is the first stage in vegetation succession. …
A ?glowing cloud? that forms when a burning‐hot ash, gas, steam, and rock emerges from a volcano and flows downhill, burning everything in its path. …
A rapid increase of one or a few species of phytoplankton in a water body, which discolours the surface water, often increases the concentration of toxins, and reduces water quality (particularly the concentration of dissolved oxygen). See also algal bloom. …
A mountain ridge that sticks up through an ice sheet. They are usually angular with sharply defined ridges, caused by intense freeze?thawweathering processes. …
A place where plants are propagated and grown to usable size, when they can be planted elsewhere. …
An area (range) that is used for grazing during the summer months by a temporary social unit of big game (cows and young calves). …