A shrub or tree species that is grown in a nursery for subsequent planting out elsewhere. …
A tree that is grown to shelter and protect other young plants which are at a vulnerable stage of growth. …
Any chemical compound (such as protein, fat, carbohydrate, vitamins, or minerals) that provides the chemical energy (food) needed by living organisms. See also macronutrient, micronutrient. …
The natural circulation of chemical elements (such as carbon and nitrogen) and compounds through specific pathways from the abiotic parts of ecosystems into the organic substances of the biotic parts, and back again to the abiotic parts. A local example of the biogeochemical cycle. …
The lack of an adequate amount of a particular nutrient which is important for the growth and health of plants and animals. …
A reduction in the level of nutrients in a habitat or ecosystem, caused by uptake by plants, removal of plant residues, or leaching, to a level at which they become unavailable for further uptake. The opposite of nutrient enrichment. …
An increase in the level of nutrients in a habitat or ecosystem. The opposite of nutrient depletion. See also eutrophication. …
The quantity of nutrients that is washed into a waterbody from its drainage basin, usually expressed as mass per unit area per unit time (kilograms per hectare per year, kg ha?1 year?1). …
contamination of water resources by excessive inputs of nutrients. See also eutrophication. …
A Norwegian philosopher, alpine climber, and influential environmental thinker (1912?2009), who coined the term deep ecology to express a vision of the world in which we protect the environment as a part of ourselves, never in opposition to humanity, based on a personal philosophy that he called ecosophy. …
A high‐level statement of what is desired in any project or activity, often expressed as a specific statement of the measurable results that are to be achieved within a stated time period. …
Without option; of a species, restricted to specific environmental conditions and thus unable to change its mode of feeding or ecological relationships. …
A beneficial symbiont that lives exclusively in the host and depends on the host for survival. Contrast facultative mutualist. …
A geological fault that involves both vertical (dip‐slope) and horizontal (strike‐slip) movements. …
The angle of tilt of the Earth's axis of rotation. …
A black or dark green extrusivevolcanic glass that is formed from fast‐cooling lava and has a similar chemical composition to granite. Also known as volcanic glass . …
From or relating to the western hemisphere. Contrast oriental. …
The final stage in the decay of a depression, where the cold front overtakes the warm front of the depression, with cold air pushing under and lifting the warm sector away from the ground surface. Also known as occluded front . See also cyclogenesis, frontogenesis. …
Exposure (for example to pollutants and toxicagents) that people incur in the course of their work. …
A federal law in the USA that defines minimum health and safety standards for the workplace. …
In epidemiology, the frequency of a disease or event in a population. See also incidence, prevalence. …
The body of saltwater that surrounds the continents and covers two‐thirds of the surface of Earth. The average depth of the ocean floor is more than 3650 metres below sea level, and the total volume of the world's oceans is estimated at around 1370 million cubic kilometres. …
The steady flow or circulation of surface water in a prevailing direction within the ocean, as a non‐tidal current. There are three types of oceanic currents: drift currents, stream currents, and upwelling currents. See also Gulf Stream. …
The disposal of hazardous wastes and other substances by dumping them in the deep waters of the oceans. See also offshore dumping. …
See Marine Protection, Research, and Sanctuaries Act (1972). …
Existing marine sources of renewable energy include ocean thermal energy, tidal power, and wave energy, and future possibilities include the construction of offshore wind power stations, exploitation of submarine geothermal energy and marine biogas energy, and energy generated by exploiting salinity gradients within the oceans. …
The ecological zone that lies beyond the continental shelf, continental slope, and continental rise; it underlies most of the major oceans, is often far from flat, and at depths greater than about 2000 metres is largely covered by fine‐textured sediment (ooze) composed mostly of organic matter. Also known as abyss or ocean bed . …
A biogeographical realm that covers the Pacific Ocean and is dominated by tropical forest. …
Relating to or occurring in the open sea, beyond the continental shelf. …
The idealized circulation pattern of the ocean that is caused by temperature and salinity gradients which lead to the transport of heat in the North Atlantic. …
That part of the Earth's crust which is formed at mid‐ocean ridges, underlies the oceans, and is generally between 5 and 10 kilometres thick. Oceanic crust is thinner, denser, and heavier than continental crust. It consists mostly of basaltic types of rocks, and geologists refer to this material as sima. Because of the movements of plate tectonics, the oceanic crust is nowhere older than about 2…
A boundary that separates masses of water within the ocean that have different temperatures and densities. …
An island in the ocean, which will often support a distinctive community of plants and animals, and may be a centre of endemism. Such islands are formed in various ways, including by breaking away from a continental landmass, volcanic action, coral formation, or a combination of processes. …
One of a number of extensive, sinuous, underwater mountain chains which are found on the ocean floor, and which mark the boundaries of some crustal plates. …
The study of the oceans, their origin, composition, history, and ecology. …
Pollution of ocean waters, both directly (such as by oil spills) and indirectly via rivers that flow into the sea. …
A deep, linear valley on the ocean floor, which runs parallel to the coast, and marks an active subduction zone at the margins of one of the continents, where one crustal plate is pushed down beneath another at a destructive plate boundary. The deepest known ocean trench is the Marianas Trench in the Pacific Ocean, which is 11?033 metres below sea level. …
The lowest concentration of a chemical or contaminant that can be smelled. …
See Organisation for Economic Co‐operation and Development. …
In greenhouse gas emissions trading, the price at which the owner of an emission reduction, credit, or allowance is willing to sell. Also known as ask . …
Funding that is provided by the government of a developed country to the governments of developing countries, to pay for particular community, health, and commercial projects. …
A form of credit‐based emissions trading. An offset is created when a source reduces its emissions by more than it is required to, on a voluntary, permanent basis. The source can then trade that offset (the extra emissions) to new sources to allow growth or relocation, with regulators approving each trade. See also bubble, netting. …
In greenhouse gasemissions trading, the ratio between the amount by which on‐site emissions are allowed to increase and the size of offset that is purchased. In US domestic emission trading programmes, new sources must offset their emissions at a ratio greater than 1:1. …
All areas seaward of the coastline. Contrast inshore. …
A breeze or light wind that blows from the land out over the sea. Also known as land breeze . Contrast onshore breeze, sea breeze. …
The disposal or dumping of waste material off or away from the shore. See also ocean dumping. …
Any facility (other than a vessel) that is located in, on, or under the water offshore, and is subject to the jurisdiction of a particular country. …
Ocean waters beyond the inshore, between about 60 and 250 nautical miles from land. …
Water that is withdrawn from surface or groundwater sources for use at another place, for public water supply, industry, irrigation, livestock, power generation, and other uses. Contrast instream use. …
The gaseffluent that is given off during any stage of an industrial process. …
Any vehicle that is intended for use on unmade surfaces or rough terrain, including all‐terrain vehicles, mini‐bikes, trail bikes, dirt bikes, dune buggies, and golf carts, but excluding snowmobiles. …
A facility for the treatment, storage, or disposal of hazardous waste that is located away from the site where that material is created. Contrast on‐site facility. …
Alternating bands of dirty and clean ice below an ice fall within a glacier, formed by summer and winter movement over the ice fall. Also known as Forbes band . …
1 In general, any viscous liquid, which includes natural plant and animals oils. 2 A thick, black, sticky hydrocarbon substance that is used to produce fuel (petroleum) and materials (plastics). Oil is one of the world's principal fossil fuel resources, and known reserves are fast being depleted. About two‐thirds of the world's known recoverable reserves are in the Middle East. Known world reser…
A method of reducing sulphur dioxide emissions from power plants that burn oil, in which the oil is treated with hydrogen (forming hydrogen sulphide gas and reducing the sulphur content of the oil) before combustion. …
An area where oil is trapped in porous rocks beneath the ground or the sea‐bed, which can be extracted via an oil well. …
A method of identifying the chemical characteristics of a particular oil, which allows oil spills to be traced to their source. …
A pipe along which oil is transported from the refinery to other places. …
Pollution of soil and water as the result of an oil spill. …
A structure that stands on the sea‐bed over a submarine oilfield, which provides a stable base above water for drilling oil wells. …
A dark grey or black shale that contains organic substances that can be distilled to yield liquid hydrocarbons, but does not contain free petroleum. …
A layer of oil floating on an area of water, usually as a result of an oil spill. …
An accidental leakage of oil from a container such as a storage tank, oil tanker, or oil pipeline, which causes pollution of the surrounding area. Oil spills at sea can causes extensive ecological and environmental damage. Toxic chemicals leach out from the oil and contaminate the surrounding water, poisoning sea life around and below the spill. Light oils can float freely on the ocean surface, an…
A cargo ship that is designed to carry crude oil in bulk. …
A vertical shaft that is drilled through rock to reach and extract the oil that is stored naturally in an oilfield beneath. At sea, the well is sunk from an oil rig. …
1 The latter part of the life cycle of an organism, after maturity. 2 A late stage in the cycle of erosion that is characterized by formation of a peneplain near sea level. Contrast maturity, youth. …
A North American term for an ecologically mature forest that has not been significantly altered by humans for at least 120 years, and which contains old trees (more than 200 years old), fallen trees, trees with broken tops, and mature and dying trees. See also ancient forest, overmature forest. …
An epoch of geological time within the Tertiary subera, stretching from 35 to 23 million years ago. …
Relating to brackish water, with a salinity of between 0.5 and 5.0 parts per thousand (?). …
A pollinator which collects pollen from a few species of plant. Contrast monolectic, polylectic. …
Deficient in the nutrients that are needed for plant growth. The term is usually applied to water or soil. Contrast eutrophic. …
A parasite that lives within more than one host during its life cycle. Contrast monoxenous. …
An olive‐green, greyish‐green, or brown silicate mineral that contains magnesium and iron, and is common in basalt and in some meteorites. …
An ecosystem (such as a raised mire) that is entirely dependent on atmospheric sources (mainly precipitation) for its supply of water and nutrients. …
An organism (such as a human) that eats both plants and animals. Contrast herbivore, carnivore. …
Capable of producing tumours in animals, which can be either benign (non‐cancerous) or malignant (cancerous). …
Of or relating to the origin and development of individual organisms. Contrast phylogenetic. …
The history of the development and growth (life cycle) of an individual. …
A facility for the treatment, storage, or disposal of hazardous waste that is located on the site where that material is created. Contrast off‐site facility. …
A type of limestone formed as a chemical precipitate, and consisting of small spherical grains of calcium carbonate that have formed around tiny nuclei. …
A fine‐textured sediment that is formed from the remains of pelagic organisms and is found on the ocean floor. …
Lack of transparency, or the ability to keep light from passing through: for example, a glass window has almost 0% opacity, whereas a concrete wall has 100% opacity. …
A mineral which transmits no light through a thin section under a microscope. Usually a native metal, sulphide, or metallic oxide mineral. …
See Organization of Petroleum Exporting Countries. …
A resource that is openly available to all users, without conditions or restrictions. …
The uncontrolled burning of waste materials in the open, either in an outdoor incinerator or an open dump, either accidentally or on purpose. …
The mining of minerals that occur near the surface, which are extracted through an open excavation. First the overburden is removed, and then the mineral materials are broken up and removed. Also known as opencut mining, open‐pit mining, surface mining . See also mountain top removal. …
An uncovered dump site in which waste is left without environmental controls. …
Unfenced, natural grazing land, which includes woodland as well as grassland. …
That part of the ocean that lies beyond the continental shelf. Similar to high sea. Contrast coastal zone. …
Public and private land that is undeveloped, which often retains its natural vegetation, and is usually used for recreation or as a reserve to protect natural areas. …
All types of land use zoning (such as large‐lot zoning and cluster zoning) which restrict land uses in order to preserve open space. …
A system that can exchange both matter and energy with its surrounding environment. Contrast closed system. …
In habitat evaluation, all clearcuts, meadows, and other openings. …
The use of analytical methods, usually with a computer, adopted from mathematics for solving operational problems. Also known as management science . …
A plant or animal that takes advantage of whatever conditions exist in the environment at the time. …
A person who is inclined to take a favourable view of the environmental crisis and what can be done about it, for example by believing that the development of new technology, better use of environmental economics, and improvement in resource management will further expand the Earth's carrying capacity. Also known as technological optimist . Contrast pessimist, environmental. See also skeptical en…
The process of making something as fully effective as possible, for example by selecting the most cost‐effective combination of management practices. …
The most favourable condition under given circumstances. …
The optimum use of available land resources in a particular place or area, defined relative to stated management objectives. …
The harvest level for a particular species that achieves the greatest overall benefits, taking into account economic, social, and biological factors. This differs from maximum sustainable yield, which considers only the biology of the species. …
A right or agreement to buy or sell a specific commodity (including emissions allowances) at a stipulated price and within a stated period of time. If the option is not exercised during that time, the money that has been paid for the option is forfeited. …
The value that people place on having the option to enjoy something (such as the use of a particular resource, or the ability to take part in a particular activity) in the future, even though they may not currently use it. The potential value of the resource for future (direct or indirect) use. …
A plantation of fruit or nut trees that is managed to yield high quality produce on a sustainable basis. …
Oil heaters that are placed in an orchard in order to generate heat and promote convective circulations to protect fruit trees from damaging low temperatures. Also known as smudge pot . …
The fourth highest category (of seven) in the scientific system of classification for organisms (taxonomy), below class and above family. Thus each class comprises more than one order, and each order comprises more than one family. …
A regulation or statute (such as a local building code) that is enacted by a city government in the USA, under powers delegated to it by the state. …
The second period of geological time in the Palaeozoic era, dating from about 510 to 440 million years ago, during which the first species of fish and fungi appear. …
Any naturally occurring mineral or rock from which economically important constituents (such as metals) can be extracted. …
A cell structure that carries out a specialized function, such as mitochondria. …
Involving, related to, or derived from living matter or living organisms, including compounds that contain carbon. …
US legislation that authorized the Secretary of Agriculture to manage the National Forests to improve and protect the forests, to secure favourable conditions of water flow, and to furnish a continuous supply of timber. …
The production of crops without the use of inorganic inputs (such as chemical fertilizers and pesticides). Fertilizer is derived from organic material such as animal manure, green manure, and compost. Also known as organic farming . See also alternative agriculture. …
The chemistry of substances that contain carbon. Contrast inorganic chemistry. …
Any compound that contains carbon which is chemically bound to hydrogen. Contrast inorganic compound. …
Material in soil that contains carbon and is derived from living plants and animals. The organic matter breaks down by decomposition to produce humus. …
nitrogen that is bound to compounds (amino acids and proteins) which contain carbon, and that must be subjected to mineralization or decomposition before it can be used by plants. Contrast inorganic nitrogen. …
A sedimentary rock (such as limestone, chalk, coal, and oil shale) that is composed of the compacted decayed remains of plants and animals. …
Any soil that contains a high percentage (usually more than 25%) of organic matter in the upper horizons, where living roots are mostly found. Contrast mineral soil. …
In general, any waste that contains carbon, which includes paper, plastics, wood, food waste, and yard waste. The term is most often used to describe material that is directly derived from plant or animal sources, which can be decomposed by micro‐organisms. …
A forum that was founded in 1961 for monitoring economic trends in its member countries from the free‐market democracies of North America, Western Europe, and the Pacific. …
An individual animal, plant, or single‐celled life form that is able to grow and reproduce. There are two main types of organism that derive energy from different sources?autotrophs that produce energy, and heterotrophs that get energy from consuming autotrophs. …
An organization that was established 1960 , consisting of 13 countries which control 60% of the world's oil reserves. OPEC negotiates with oil companies on matters of oil production, prices, and future concession rights. …
A synthetic organic compound that contains chlorine, is highly toxic, and has a variety of forms and uses including aerosol propellants, plasticisers, transformer coolants, and food packaging. Its greatest use was in pesticides, in the form of DDT, aldrine, and lindane. Organochlorines accumulate in the fatty tissue of animals, and can reach toxic levels in predators through biomagnification in th…
A synthetic organic compound that contains phosphate, and is used as a pesticide that works by interfering with an insect's nervous system. Organophosphates are generally considered safer than organochlorines because they break down rapidly in the environment and do not bioaccumulate, but are highly toxic to mammals (including humans) and may be carcinogenic. …
From or relating to the eastern hemisphere. Contrast occidental. …
A plant that is grown and prized for its beauty rather than for its produce (such as fruit). Such plants are often exotic and planted deliberately. …
A belt of deformed rocks that make up the continental crust around a craton. Many have been deformed into fold mountains. …
The formation of mountain ranges by tectonic processes, particularly large‐scale compression and intense upward displacement. Also known as orogeny . …
A major range of mountains on the continents that has been created by folding and other deformation in a mountain‐building episode. …
precipitation (usually rain or snow) that results from the lifting of a moisture‐bearing air mass over a topographic barrier such as a mountain range. The leeward slope, beyond the barrier, is often dry and forms a rain shadow. …
The lifting of air over a topographic barrier such a hill or mountain. …
seed that can be dried and stored long‐term, at low temperature and humidity, and remain viable. …
See Convention for the Prevention of Marine Pollution by Dumping from Ships and Aircraft. …
The process by which a solvent can pass through a semipermeablemembrane, from a dilute solution into a more concentrated solution. …
Tiny marine and freshwater crustaceans that have a shrimp‐like body which is enclosed in a bivalve shell. Also known as seed shrimp . …
The title of the 1987 report of the World Commission on Environment and Development, more commonly known as the Brundtland Report, which defined sustainable development. …
A controversial book by Theo Colborn , Dianne Dumanoski , and John Peterson Myers ( 1997 ), which outlined how toxic pollutants such as chemical pesticides cause birth defects, sexual abnormalities, and reproductive failures in wildlife. It built on Rachel Carson 's Silent Spring. …
The mating of individuals which are genetically unrelated. Also known as outcross . See also breeding, inbreeding. …
A system, managed by the US Department of Agriculture Forest Service, that provides outdoor recreation opportunities and wilderness experiences within the USA. …
The place where a sewer, drain, or stream discharges. …
The flow of air out of a thunderstorm, or of water out of a lake or reservoir. …
The release of gas (such as water vapour, nitrogen, or argon) from cooling molten rock or the interior of the Earth. …
The energy, matter, or information that leaves a system. Contrast input. …
Sand and gravel that is deposited by meltwater streams in the pro‐glacial environment, or beyond the margin of an active glacier. …
The relatively flat area beyond the margins of a retreating glacier, where meltwater streams draining from the ice deposit sand, gravel, and mud washed out from the glacier. Most outwash plains are wide and extensive, but some (valley trains) are confined within a narrow valley. …
The deposition of alluvial sediment on the surface of a floodplain by a river under flood (over the bank) conditions. …
The overgrazing of shrubs and trees by a large population of animals that browse. …
The layer of soil, sediment, and rock that covers a mineral deposit (such as coal), and must be removed to allow surface mining. …
The sky condition when more than nine‐tenths of the sky is covered by clouds. …
The use or extraction of a resource to the point of depletion (for inorganic resources) or extinction (for organic resources), or the reduction of a population to a level below the minimum needed for sustainable yield. Activity that exceeds the carrying capacity. Also known as overharvesting . …
fishing beyond a sustainable level, caused by harvesting so many fish (particularly immature individuals) of a particular species that the breeding stock left is not large enough to replenish the species. Overexploitation of fish populations. …
The damage or destruction of natural vegetation (particularly grasses and forbs) that is caused when too many herbivores are allowed to graze on it before it has a chance to recover from previous grazing. A form of overexploitation. …
The flow of water over the ground surface towards stream channels. Also known as sheet flow . …
An old growth forest in which tree growth has almost ceased, and decay and deterioration are increasing. …
A situation in which an existing population is too large (perhaps because of a population explosion) to be adequately supported by available resources on a sustainable basis, at current levels of consumption. A population size that exceeds the carrying capacity of the environment, and is likely to lead to a population crash. Also known as overshoot . See also Malthus, Thomas . …
A managed forest in which the trees are so closely spaced that they compete for resources, and grow more slowly as a result. …
Allowing too many animals to graze a particular area, usually for a short period of time. Continued overstocking will lead to overgrazing. …
The crown or upper canopy of branches and leaves in a stand of stratified vegetation, which decreases the amount of sunlight that reaches the ground below. Contrast understorey. …
An announced release of a biological agent, by terrorists or others. Contrast covert release. …
A type of fold in rock, which is created where compressional forces are asymmetrical, so that one limb of the fold is pushed over the other limb and over‐rides it. See also nappe. …
The use of renewable resources faster than natural processes can replace them, which is not sustainable. …
Egg laying; producing fertilized eggs that develop and hatch outside the female's body …
A substance that causes oxidation in other substances by underoing reduction itself. Also known as an oxidizer or oxidizing agent . …
1 A chemical process in which an element reacts with oxygen, where oxygen is gained, or electrons are lost. 2 A common form of chemical weathering of rocks, which involves the combination of rock materials (such as silicates or carbonates of iron or manganese) with oxygen and water. …
An artificial pond or lagoon that contains water in which waste is consumed by bacteria as part of a waste treatment process. Also known as sewage lagoon . …
A compound of oxygen with another element or group. Examples include sulphur dioxide and nitrogen oxides. …
To add oxygen to or combine with oxygen, or to lose electrons. …
A type (order) of deeply weathered soil that contain clays of iron and aluminium oxides, has low fertility, and is acidic. …
A special type of gasoline which has been blended with alcohols or ethers (which contain oxygen), in order to reduce emissions of carbon monoxide and other greenhouse gases. Also known as oxyfuel . …
See biological oxygen demand, chemical oxygen demand. …
A decrease in the concentration of dissolved oxygen in a waterbody downstream from a point source of pollutants, which is caused by the uptake of oxygen by bacteria, fungi, and invertebrates in the water as they break down the pollutants by aerobicdecomposition. Also known as oxygen sag . …
Any of the oxygen atoms that have the same atomic number (number of protons) but different mass numbers (different numbers of neutrons). The two common stable isotopes of oxygen are 16O and 18O, where 16O is the more abundant of the two. …
The ratio between the two stable isotopes of oxygen (16O and 18O) in a sample such as old layers of ice or shells from ocean sediments. The ratio is temperature dependent and provides a reliable indicator (proxy) of past climatic conditions. …
The level in a waterbody, usually below the thermocline, below which there is very little dissolved oxygen. …
An invisible, colourless, tasteless, odourless gas that exists naturally in air (21% by volume), accounts for 46.6% of the Earth's crust, and is the most abundant element on Earth. It is produced by plants during photosynthesis, and it is essential for aerobicrespiration (it is breathed by humans and other animals). The Earth's early atmosphere probably contained little oxygen, but after the evolu…
The ability of oxygen gas to dissolve into water. …
A lake that is formed on the floodplain of an alluvial river when the river cuts through the narrow neck of a large meander. Also known as a cut‐off . …
The application of ozone to water for purification purposes (as a disinfectant, and to improve taste or control odour). …
A mechanical device that creates ozone, which is used to oxidize water in order to eliminate organic wastes. …
Any of a group of chemicals that destroy ozone and attack the ozone layer in the stratosphere. Most are chemically stable compounds that contain chlorine or bromine, which remain unchanged long enough to drift up to the stratosphere. The best known are chlorofluorocarbons (CFCs), but others include halons (which are used in some fire extinguishers), methyl chloroform and carbon tetrachloride (sol…
The destruction of the stratospheric ozone layer, which shields the Earth from ultraviolet (UV) radiation, caused by the breakdown of certain compounds (chlorofluorocarbons or halons) that contain chlorine and/or bromine, which destroy ozone molecules in the stratosphere. In 1985 British scientists discovered a seasonal thinning (usually referred to as a hole), the size of the USA, in the ozone…
A relative index of the extent to which a particular chemical may cause ozone depletion, compared with CFC‐11 and CFC‐12 which have an OPD of 1.0 Other CFCs and HCFCs have ODPs that range between 0.016 and 1.0, halons have ODPs ranging up to 10, and HFCs have an ODP of 0 because they do not contain chlorine. …
A highly reactive greenhouse gas, made of three atoms of oxygen. Ozone comprises 0.00006% of the Earth's atmosphere. It is formed when the molecule of the stable form of oxygen (O2) is split by ultravioletradiation or electrical discharge, for example when lightning flashes through a cloud. There are two distinctly different ozone problems: depletion of stratospheric ozone, and increasing concentr…
General name for a sharp seasonal decrease in the concentration of ozone in the stratosphere that occurs over Antarctica in the spring, was first detected during the 1970s, and is growing larger (a larger decrease, over a larger area) through time. See also ozone depletion. …
The natural protective layer of ozone in the stratosphere that is formed naturally by a photochemical reaction with solar ultravioletradiation. Ozone is constantly being formed, broken down, and re‐formed above about 40 kilometres, and it sinks and accumulates at the 20?25 kilometres level. The ozone layer is not uniform around the world; it varies in density, being least dense over the equator …
Measurements of background levels of ozone that have been collected over 20 years at sites a long way from pollution sources (including the South Pole, Barrow in Alaska, and Mauna Loa in Hawaii). These baseline surveys show that ozone concentrations vary through the day and from season to season. Efforts are being made through the International Geosphere‐Biosphere Programme to collect more infor…
The layer rich in organic matter within the A‐horizon of a soil. …
The largest ocean in the world, which covers a third of the Earth's surface, contains about 25?000 islands (more than half of the global total), and is regularly affected by typhoons and hurricanes, volcanoes, earthquakes, and tsunamis. …
General term for the 34 countries and 23 island states that are situated in and around the Pacific Ocean and share similar political, economic, and environmental interests. …
A volcanic zone that runs right around the edges of the Pacific Ocean, along a series of subduction zones of convergent plate boundaries, where the moving plates of the Pacific plunge beneath the confining plates to the east, north, and west. It extends through the Andes in South America, runs through Central America and Mexico, along the west coast of the USA into Alaska, across the Aleutian Isla…
Materials that are used for the containment, protection, handling, delivery, and presentation of goods. …
Seawater that is frozen into thick blocks of ice, under permanently cold conditions, such as those found around the polar ice caps. See also sea ice, ice floe. …
An enclosed area of grazing land for animals, such as horses. …
A form of reproduction in insects in which the larval stage reproduces without maturing first. See also larval paedogenesis, pupal paedogenesis. …
Volcanic lava that solidifies into ropy or corded shapes with a smooth surface. The name is a Hawaiian word meaning satin‐like. …
A biogeographical region that covers Europe, Asia, and North Africa. …
A biogeographical realm that covers much of Europe and Asia, and contains a variety of biomes including tundra, grassland, deciduous forest, coniferous forest, chaparral, and desert. …
The study of the origin, growth, and structure of fossil animals and plants as living organisms. …
The first epoch of geological time within the Palaeogene, between 65 and 56 million years ago. …
The climate of a particular period in the geological past, before historical records or instrumental observations. …
The study and reconstruction of past climates and of climate change. …
