277 relations: Abiotic component, Adaptation, Aesthetics, Agriculture, American Meteorological Society, Anaerobic digestion, Animal, Archaea, Archipelago, Arctic Ocean, Argon, Artificiality, Atlantic Ocean, Atmosphere, Atmosphere of Earth, Atmospheric pressure, Avoiding Dangerous Climate Change, Bacteria, Bank (geography), Beaver dam, Biodiversity, Biogeochemical cycle, Biogeographic realm, Biology, Biome, Biosphere, Biotic component, Biotope, Body of water, Built environment, C. W. Thornthwaite, Carbon, Carbon cycle, Carbon dioxide, Carbon-based life, Cell (biology), Cell growth, Channel (geography), Chaos theory, Chemical compound, Chemistry, Chlorine, Chronology, Climate, Climate change, Climate change adaptation, Climate change mitigation, Climate classification, Climax community, Cloud, ..., Community (ecology), Compost, Conservation movement, Continent, Convection, Crust (geology), Cryosphere, Current (stream), Depression (geology), Desert, Dichotomy, Discipline, Distributed generation, DNA, Domestication, Dust, Earth, Earth science, Earth's rotation, Ecological succession, Ecological unit, Ecology, Ecosystem, Effects of global warming, Electric charge, Endangered species, Endorheic basin, Energy, Environment (biophysical), Environmental science, Environmentalism, Environmentalist, Etymology, Eugene Odum, Evapotranspiration, Exosphere, Extratropical cyclone, Fish pond, Floodplain, Flow velocity, Fluorine, Forest, Fossil fuel, Fresh water, Fungus, Gaia hypothesis, Gas, Gene, Geodesy, Geography, Geology, Geophysics, Glacier, Global warming, Grassland, Greenhouse gas, Groundwater recharge, Habitat, Habitat conservation, Habitat fragmentation, Helium, Homeostasis, Human, Human ecosystem, Human impact on the environment, Humidity, Hut, Hydrogen, Hydrology, Hydrosphere, Ice, Ice age, Igneous rock, Index of environmental articles, Indian Ocean, Industry, Inert gas, Inorganic compound, International Space Station, Ionosphere, Jet stream, Kyoto Protocol, Lake, Land development, Landform, Life, List of environmental issues, List of environmental websites, List of natural phenomena, Lithosphere, Magma, Magnetism, Mantle (geology), Mantle plume, Mathematics, Mercury (element), Mesosphere, Metabolism, Meteoroid, Meteorology, Microorganism, Mid-ocean ridge, Middle latitudes, Mineralogy, Moral, Mound-building termites, Mountain, Nation, Natural capital, Natural history, Natural landscape, Natural resource, Natural selection, Nature, Nature reserve, Nitrogen, Nitrogen cycle, Ocean, Old English, Organic compound, Organism, Organization, Oxygen, Oxygen cycle, Ozone layer, Pacific Ocean, Park, Parts-per notation, Pedosphere, Phenomenon, Philosophy, Phosphorus, Phosphorus cycle, Photosynthesis, Photovoltaic system, Physics, Physiology, Planetary boundary layer, Plant, Plate tectonics, Politics, Pollen, Pollutant, Pollution, Pond, Precipitation, Protist, Public transport, Rachel Carson, Radiation, Radioactive decay, Radionuclide, Rain, Recreation, Recycling, Renewable energy, Reproduction, Reuse, Rheid, Rift zone, Rock (geology), Salinity, Savanna, Science, Sea, Sea spray, Seabed, Seawater, Sociology, Soil, Soil biology, Soil structure, Solar pond, Southern Ocean, Species, Spore, Spring (hydrology), Stimulus (physiology), Stratopause, Stratosphere, Stream, Stream bed, Stream pool, Subduction, Sulfur, Sulfur dioxide, Sunlight, Surface runoff, Suspension (chemistry), Sustainability, Sustainable agriculture, Temperature, Thermosphere, Tide pool, Time, Timeline of environmental history, Toxicant, Tropopause, Troposphere, Turbulence, Ultraviolet, United Nations Framework Convention on Climate Change, Urban area, Volcanic ash, Volcano, Waste management, Waste minimisation, Waste-to-energy, Water, Water cycle, Water garden, Water stagnation, Water vapor, Watercourse, Weather, Weather modification, Western Climate Initiative, Wilderness, Wildflower, Wildlife, Wildlife corridor, Wildness, Wind, Wladimir Köppen, World Ocean, Zero waste, 1,000,000,000. Expand index (227 more) » « Shrink index
In biology and ecology, abiotic components or abiotic factors are non-living chemical and physical parts of the environment that affect living organisms and the functioning of ecosystems.
In biology, adaptation has three related meanings.
Aesthetics (also spelled esthetics) is a branch of philosophy that explores the nature of art, beauty, and taste, with the creation and appreciation of beauty.
Agriculture is the cultivation of land and breeding of animals and plants to provide food, fiber, medicinal plants and other products to sustain and enhance life.
The American Meteorological Society (AMS) is the premier scientific and professional organization in the United States promoting and disseminating information about the atmospheric, oceanic, and hydrologic sciences. Its mission is to advance the atmospheric and related sciences, technologies, applications, and services for the benefit of society.
Anaerobic digestion is a collection of processes by which microorganisms break down biodegradable material in the absence of oxygen.
Animals are multicellular eukaryotic organisms that form the biological kingdom Animalia.
Archaea (or or) constitute a domain of single-celled microorganisms.
An archipelago, sometimes called an island group or island chain, is a chain, cluster or collection of islands, or sometimes a sea containing a small number of scattered islands.
The Arctic Ocean is the smallest and shallowest of the world's five major oceans.
Argon is a chemical element with symbol Ar and atomic number 18.
Artificiality (also called factitiousness, or the state of being artificial or man-made) is the state of being the product of intentional human manufacture, rather than occurring naturally through processes not involving or requiring human activity.
The Atlantic Ocean is the second largest of the world's oceans with a total area of about.
An atmosphere is a layer or a set of layers of gases surrounding a planet or other material body, that is held in place by the gravity of that body.
The atmosphere of Earth is the layer of gases, commonly known as air, that surrounds the planet Earth and is retained by Earth's gravity.
Atmospheric pressure, sometimes also called barometric pressure, is the pressure within the atmosphere of Earth (or that of another planet).
Avoiding Dangerous Climate Change: A Scientific Symposium on Stabilisation of Greenhouse Gases was a 2005 international conference that examined the link between atmospheric greenhouse gas concentration, and the 2 °C (3.6 °F) ceiling on global warming thought necessary to avoid the most serious effects of global warming.
Bacteria (common noun bacteria, singular bacterium) is a type of biological cell.
In geography, the word bank generally refers to the land alongside a body of water.
Beaver dams are dams built by beavers to provide ponds as protection against predators such as coyotes, wolves, and bears, and to provide easy access to food during winter.
Biodiversity, a portmanteau of biological (life) and diversity, generally refers to the variety and variability of life on Earth.
In geography and Earth science, a biogeochemical cycle or substance turnover or cycling of substances is a pathway by which a chemical substance moves through biotic (biosphere) and abiotic (lithosphere, atmosphere, and hydrosphere) compartments of Earth.
A biogeographic realm or ecozone is the broadest biogeographic division of the Earth's land surface, based on distributional patterns of terrestrial organisms.
Biology is the natural science that studies life and living organisms, including their physical structure, chemical composition, function, development and evolution.
A biome is a community of plants and animals that have common characteristics for the environment they exist in.
The biosphere (from Greek βίος bíos "life" and σφαῖρα sphaira "sphere") also known as the ecosphere (from Greek οἶκος oîkos "environment" and σφαῖρα), is the worldwide sum of all ecosystems.
Biotic components or biotic factors, can be described as any living component that affects another organism, or shapes the ecosystem.
A biotope is an area of uniform environmental conditions providing a living place for a specific assemblage of plants and animals.
A body of water or waterbody (often spelled water body) is any significant accumulation of water, generally on a planet's surface.
In social science, the term built environment, or built world, refers to the human-made surroundings that provide the setting for human activity, ranging in scale from buildings to parks.
Charles Warren Thornthwaite (March 7, 1899 – June 11, 1963) was an American geographer and climatologist.
Carbon (from carbo "coal") is a chemical element with symbol C and atomic number 6.
The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of the Earth.
Carbon dioxide (chemical formula) is a colorless gas with a density about 60% higher than that of dry air.
Carbon is a key component of all known life on Earth, representing approximately 45-50% of all dry biomass.
The cell (from Latin cella, meaning "small room") is the basic structural, functional, and biological unit of all known living organisms.
The term cell growth is used in the contexts of biological cell development and cell division (reproduction).
In physical geography, a channel is a type of landform consisting of the outline of a path of relatively shallow and narrow body of fluid, most commonly the confine of a river, river delta or strait.
Chaos theory is a branch of mathematics focusing on the behavior of dynamical systems that are highly sensitive to initial conditions.
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) composed of atoms from more than one element held together by chemical bonds.
Chemistry is the scientific discipline involved with compounds composed of atoms, i.e. elements, and molecules, i.e. combinations of atoms: their composition, structure, properties, behavior and the changes they undergo during a reaction with other compounds.
Chlorine is a chemical element with symbol Cl and atomic number 17.
Chronology (from Latin chronologia, from Ancient Greek χρόνος, chrónos, "time"; and -λογία, -logia) is the science of arranging events in their order of occurrence in time.
Climate is the statistics of weather over long periods of time.
Climate change is a change in the statistical distribution of weather patterns when that change lasts for an extended period of time (i.e., decades to millions of years).
Climate change adaptation is a response to global warming and climate change, that seeks to reduce the vulnerability of social and biological systems to relatively sudden change and thus offset the effects of global warming.
Climate change mitigation consists of actions to limit the magnitude or rate of long-term climate change.
Climate classification systems are ways of classifying the world's climates.
In ecology, climax community, or climatic climax community, is a historic term for a biological community of plants, animals, and fungi which, through the process of ecological succession in the development of vegetation in an area over time, have reached a steady state.
In meteorology, a cloud is an aerosol consisting of a visible mass of minute liquid droplets, frozen crystals, or other particles suspended in the atmosphere of a planetary body.
In ecology, a community is a group or association of populations of two or more different species occupying the same geographical area and in a particular time, also known as a biocoenosis The term community has a variety of uses.
Compost is organic matter that has been decomposed in a process called composting.
The conservation movement, also known as nature conservation, is a political, environmental, and social movement that seeks to protect natural resources including animal and plant species as well as their habitat for the future.
A continent is one of several very large landmasses of the world.
Convection is the heat transfer due to bulk movement of molecules within fluids such as gases and liquids, including molten rock (rheid).
In geology, the crust is the outermost solid shell of a rocky planet, dwarf planet, or natural satellite.
The cryosphere (from the Greek κρύος kryos, "cold", "frost" or "ice" and σφαῖρα sphaira, "globe, ball") is those portions of Earth's surface where water is in solid form, including sea ice, lake ice, river ice, snow cover, glaciers, ice caps, ice sheets, and frozen ground (which includes permafrost).
A current, in a river or stream, is the flow of water influenced by gravity as the water moves downhill to reduce its potential energy.
A depression in geology is a landform sunken or depressed below the surrounding area.
A desert is a barren area of landscape where little precipitation occurs and consequently living conditions are hostile for plant and animal life.
A dichotomy is a partition of a whole (or a set) into two parts (subsets).
Discipline is action or inaction that is regulated to be in accordance (or to achieve accord) with a system of governance.
Distributed generation, also distributed energy, on-site generation (OSG) or district/decentralized energy is electrical generation and storage performed by a variety of small, grid-connected devices referred to as distributed energy resources (DER).
Deoxyribonucleic acid (DNA) is a thread-like chain of nucleotides carrying the genetic instructions used in the growth, development, functioning and reproduction of all known living organisms and many viruses.
Domestication is a sustained multi-generational relationship in which one group of organisms assumes a significant degree of influence over the reproduction and care of another group to secure a more predictable supply of resources from that second group.
Dust are fine particles of matter.
Earth is the third planet from the Sun and the only astronomical object known to harbor life.
Earth science or geoscience is a widely embraced term for the fields of natural science related to the planet Earth.
Earth's rotation is the rotation of Planet Earth around its own axis.
Ecological succession is the process of change in the species structure of an ecological community over time.
Ecological units, comprise concepts such as population, community, and - in particular - the ecosystem as the basic unit, which are at the basis of ecological theory and research.
Ecology (from οἶκος, "house", or "environment"; -λογία, "study of") is the branch of biology which studies the interactions among organisms and their environment.
An ecosystem is a community made up of living organisms and nonliving components such as air, water, and mineral soil.
The effects of global warming are the environmental and social changes caused (directly or indirectly) by human emissions of greenhouse gases.
Electric charge is the physical property of matter that causes it to experience a force when placed in an electromagnetic field.
An endangered species is a species which has been categorized as very likely to become extinct.
An endorheic basin (also endoreic basin or endorreic basin) (from the ἔνδον, éndon, "within" and ῥεῖν, rheîn, "to flow") is a limited drainage basin that normally retains water and allows no outflow to other external bodies of water, such as rivers or oceans, but converges instead into lakes or swamps, permanent or seasonal, that equilibrate through evaporation.
In physics, energy is the quantitative property that must be transferred to an object in order to perform work on, or to heat, the object.
A biophysical environment is a biotic and abiotic surrounding of an organism or population, and consequently includes the factors that have an influence in their survival, development, and evolution.
Environmental science is an interdisciplinary academic field that integrates physical, biological and information sciences (including ecology, biology, physics, chemistry, plant science, zoology, mineralogy, oceanology, limnology, soil science, geology and physical geography (geodesy), and atmospheric science) to the study of the environment, and the solution of environmental problems.
Environmentalism or environmental rights is a broad philosophy, ideology, and social movement regarding concerns for environmental protection and improvement of the health of the environment, particularly as the measure for this health seeks to incorporate the impact of changes to the environment on humans, animals, plants and non-living matter.
An environmentalist is a supporter of the goals of the environmental movement, "a political and ethical movement that seeks to improve and protect the quality of the natural environment through changes to environmentally harmful human activities".
EtymologyThe New Oxford Dictionary of English (1998) – p. 633 "Etymology /ˌɛtɪˈmɒlədʒi/ the study of the class in words and the way their meanings have changed throughout time".
Eugene Pleasants Odum (September 17, 1913 – August 10, 2002) was an American biologist at the University of Georgia known for his pioneering work on ecosystem ecology.
Evapotranspiration (ET) is the sum of evaporation and plant transpiration from the Earth's land and ocean surface to the atmosphere.
The exosphere (ἔξω éxō "outside, external, beyond", σφαῖρα sphaĩra "sphere") is a thin, atmosphere-like volume surrounding a planet or natural satellite where molecules are gravitationally bound to that body, but where the density is too low for them to behave as a gas by colliding with each other.
Extratropical cyclones, sometimes called mid-latitude cyclones or wave cyclones, are low-pressure areas which, along with the anticyclones of high-pressure areas, drive the weather over much of the Earth.
A fish pond, or fishpond, is a controlled pond, artificial lake, or reservoir that is stocked with fish and is used in aquaculture for fish farming, or is used for recreational fishing or for ornamental purposes.
A floodplain or flood plain is an area of land adjacent to a stream or river which stretches from the banks of its channel to the base of the enclosing valley walls, and which experiences flooding during periods of high discharge.
In continuum mechanics the macroscopic velocity, also flow velocity in fluid dynamics or drift velocity in electromagnetism, is a vector field used to mathematically describe the motion of a continuum.
Fluorine is a chemical element with symbol F and atomic number 9.
A forest is a large area dominated by trees.
A fossil fuel is a fuel formed by natural processes, such as anaerobic decomposition of buried dead organisms, containing energy originating in ancient photosynthesis.
Fresh water (or freshwater) is any naturally occurring water except seawater and brackish water.
A fungus (plural: fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms.
The Gaia hypothesis, also known as the Gaia theory or the Gaia principle, proposes that living organisms interact with their inorganic surroundings on Earth to form a synergistic and self-regulating, complex system that helps to maintain and perpetuate the conditions for life on the planet.
Gas is one of the four fundamental states of matter (the others being solid, liquid, and plasma).
In biology, a gene is a sequence of DNA or RNA that codes for a molecule that has a function.
Geodesy, also known as geodetics, is the earth science of accurately measuring and understanding three of Earth's fundamental properties: its geometric shape, orientation in space, and gravitational field.
Geography (from Greek γεωγραφία, geographia, literally "earth description") is a field of science devoted to the study of the lands, the features, the inhabitants, and the phenomena of Earth.
Geology (from the Ancient Greek γῆ, gē, i.e. "earth" and -λoγία, -logia, i.e. "study of, discourse") is an earth science concerned with the solid Earth, the rocks of which it is composed, and the processes by which they change over time.
Geophysics is a subject of natural science concerned with the physical processes and physical properties of the Earth and its surrounding space environment, and the use of quantitative methods for their analysis.
A glacier is a persistent body of dense ice that is constantly moving under its own weight; it forms where the accumulation of snow exceeds its ablation (melting and sublimation) over many years, often centuries.
Global warming, also referred to as climate change, is the observed century-scale rise in the average temperature of the Earth's climate system and its related effects.
Grasslands are areas where the vegetation is dominated by grasses (Poaceae); however, sedge (Cyperaceae) and rush (Juncaceae) families can also be found along with variable proportions of legumes, like clover, and other herbs.
A greenhouse gas is a gas in an atmosphere that absorbs and emits radiant energy within the thermal infrared range.
Groundwater recharge or deep drainage or deep percolation is a hydrologic process where water moves downward from surface water to groundwater.
In ecology, a habitat is the type of natural environment in which a particular species of organism lives.
Habitat conservation is a management practice that seeks to conserve, protect and restore habitat areas for wild plants and animals, especially conservation reliant species, and prevent their extinction, fragmentation or reduction in range.
Habitat fragmentation describes the emergence of discontinuities (fragmentation) in an organism's preferred environment (habitat), causing population fragmentation and ecosystem decay.
Helium (from lit) is a chemical element with symbol He and atomic number 2.
Homeostasis is the tendency of organisms to auto-regulate and maintain their internal environment in a stable state.
Humans (taxonomically Homo sapiens) are the only extant members of the subtribe Hominina.
Human ecosystems are complex cybernetic systems that are increasingly being used by ecological anthropologists and other scholars to examine the ecological aspects of human communities in a way that integrates multiple factors as economics, socio-political organization, psychological factors, and physical factors related to the environment.
Human impact on the environment or anthropogenic impact on the environment includes changes to biophysical environments and ecosystems, biodiversity, and natural resources caused directly or indirectly by humans, including global warming, environmental degradation (such as ocean acidification), mass extinction and biodiversity loss, ecological crises, and ecological collapse.
Humidity is the amount of water vapor present in the air.
A hut is a primitive dwelling, which may be constructed of various local materials.
Hydrogen is a chemical element with symbol H and atomic number 1.
Hydrology is the scientific study of the movement, distribution, and quality of water on Earth and other planets, including the water cycle, water resources and environmental watershed sustainability.
The hydrosphere (from Greek ὕδωρ hydōr, "water" and σφαῖρα sphaira, "sphere") is the combined mass of water found on, under, and above the surface of a planet, minor planet or natural satellite.
Ice is water frozen into a solid state.
An ice age is a period of long-term reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers.
Igneous rock (derived from the Latin word ignis meaning fire), or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic.
The natural environment, commonly referred to simply as the environment, includes all living and non-living things occurring naturally on Earth.
The Indian Ocean is the third largest of the world's oceanic divisions, covering (approximately 20% of the water on the Earth's surface).
Industry is the production of goods or related services within an economy.
An inert gas/noble gas is a gas which does not undergo chemical reactions under a set of given conditions.
An inorganic compound is typically a chemical compound that lacks C-H bonds, that is, a compound that is not an organic compound, but the distinction is not defined or even of particular interest.
The International Space Station (ISS) is a space station, or a habitable artificial satellite, in low Earth orbit.
The ionosphere is the ionized part of Earth's upper atmosphere, from about to altitude, a region that includes the thermosphere and parts of the mesosphere and exosphere.
Jet streams are fast flowing, narrow, meandering air currents in the atmospheres of some planets, including Earth.
The Kyoto Protocol is an international treaty which extends the 1992 United Nations Framework Convention on Climate Change (UNFCCC) that commits state parties to reduce greenhouse gas emissions, based on the scientific consensus that (part one) global warming is occurring and (part two) it is extremely likely that human-made CO2 emissions have predominantly caused it.
A lake is an area filled with water, localized in a basin, that is surrounded by land, apart from any river or other outlet that serves to feed or drain the lake.
Land development is altering the landscape in any number of ways such as.
A landform is a natural feature of the solid surface of the Earth or other planetary body.
Life is a characteristic that distinguishes physical entities that do have biological processes, such as signaling and self-sustaining processes, from those that do not, either because such functions have ceased, or because they never had such functions and are classified as inanimate.
This is an alphabetical list of environmental issues, harmful aspects of human activity on the biophysical environment.
This list of environmental websites includes websites, blogs, podcasts and other web-based platforms associated with environmental issues.
Types of natural phenomena include, but are not limited to, the following: Weather, fog, thunder, tornadoes; biological processes, decomposition, germination; physical processes, wave propagation, erosion; tidal flow, and natural disasters such as electromagnetic pulses, volcanic eruptions, and earthquakes.
A lithosphere (λίθος for "rocky", and σφαίρα for "sphere") is the rigid, outermost shell of a terrestrial-type planet, or natural satellite, that is defined by its rigid mechanical properties.
Magma (from Ancient Greek μάγμα (mágma) meaning "thick unguent") is a mixture of molten or semi-molten rock, volatiles and solids that is found beneath the surface of the Earth, and is expected to exist on other terrestrial planets and some natural satellites.
Magnetism is a class of physical phenomena that are mediated by magnetic fields.
The mantle is a layer inside a terrestrial planet and some other rocky planetary bodies.
A mantle plume is an upwelling of abnormally hot rock within the Earth's mantle, first proposed by J. Tuzo Wilson in 1963.
Mathematics (from Greek μάθημα máthēma, "knowledge, study, learning") is the study of such topics as quantity, structure, space, and change.
Mercury is a chemical element with symbol Hg and atomic number 80.
The mesosphere (from Greek mesos "middle" and sphaira "sphere") is the layer of the Earth's atmosphere that is directly above the stratosphere and directly below the thermosphere.
Metabolism (from μεταβολή metabolē, "change") is the set of life-sustaining chemical transformations within the cells of organisms.
A meteoroid is a small rocky or metallic body in outer space.
Meteorology is a branch of the atmospheric sciences which includes atmospheric chemistry and atmospheric physics, with a major focus on weather forecasting.
A microorganism, or microbe, is a microscopic organism, which may exist in its single-celled form or in a colony of cells. The possible existence of unseen microbial life was suspected from ancient times, such as in Jain scriptures from 6th century BC India and the 1st century BC book On Agriculture by Marcus Terentius Varro. Microbiology, the scientific study of microorganisms, began with their observation under the microscope in the 1670s by Antonie van Leeuwenhoek. In the 1850s, Louis Pasteur found that microorganisms caused food spoilage, debunking the theory of spontaneous generation. In the 1880s Robert Koch discovered that microorganisms caused the diseases tuberculosis, cholera and anthrax. Microorganisms include all unicellular organisms and so are extremely diverse. Of the three domains of life identified by Carl Woese, all of the Archaea and Bacteria are microorganisms. These were previously grouped together in the two domain system as Prokaryotes, the other being the eukaryotes. The third domain Eukaryota includes all multicellular organisms and many unicellular protists and protozoans. Some protists are related to animals and some to green plants. Many of the multicellular organisms are microscopic, namely micro-animals, some fungi and some algae, but these are not discussed here. They live in almost every habitat from the poles to the equator, deserts, geysers, rocks and the deep sea. Some are adapted to extremes such as very hot or very cold conditions, others to high pressure and a few such as Deinococcus radiodurans to high radiation environments. Microorganisms also make up the microbiota found in and on all multicellular organisms. A December 2017 report stated that 3.45 billion year old Australian rocks once contained microorganisms, the earliest direct evidence of life on Earth. Microbes are important in human culture and health in many ways, serving to ferment foods, treat sewage, produce fuel, enzymes and other bioactive compounds. They are essential tools in biology as model organisms and have been put to use in biological warfare and bioterrorism. They are a vital component of fertile soils. In the human body microorganisms make up the human microbiota including the essential gut flora. They are the pathogens responsible for many infectious diseases and as such are the target of hygiene measures.
A mid-ocean ridge (MOR) is an underwater mountain system formed by plate tectonics.
The middle latitudes (also called the mid-latitudes, sometimes midlatitudes, or moderate latitudes) of Earth lie between 23°26'22" and 66°33'39" north, and between 23°26'22" and 66°33'39" south.
Mineralogy is a subject of geology specializing in the scientific study of chemistry, crystal structure, and physical (including optical) properties of minerals and mineralized artifacts.
A moral (from Latin morālis) is a message that is conveyed or a lesson to be learned from a story or event.
Mound-building termites are a group of termite species that live in mounds.
A mountain is a large landform that stretches above the surrounding land in a limited area, usually in the form of a peak.
A nation is a stable community of people, formed on the basis of a common language, territory, economic life, ethnicity or psychological make-up manifested in a common culture.
Natural capital is the world's stock of natural resources, which includes geology, soils, air, water and all living organisms.
Natural history is a domain of inquiry involving organisms including animals, fungi and plants in their environment; leaning more towards observational than experimental methods of study.
A natural landscape is the original landscape that exists before it is acted upon by human culture.
Natural resources are resources that exist without actions of humankind.
Natural selection is the differential survival and reproduction of individuals due to differences in phenotype.
Nature, in the broadest sense, is the natural, physical, or material world or universe.
A nature reserve (also called a natural reserve, bioreserve, (natural/nature) preserve, or (national/nature) conserve) is a protected area of importance for wildlife, flora, fauna or features of geological or other special interest, which is reserved and managed for conservation and to provide special opportunities for study or research.
Nitrogen is a chemical element with symbol N and atomic number 7.
The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into multiple chemical forms as it circulates among the atmosphere, terrestrial, and marine ecosystems.
An ocean (the sea of classical antiquity) is a body of saline water that composes much of a planet's hydrosphere.
Old English (Ænglisc, Anglisc, Englisc), or Anglo-Saxon, is the earliest historical form of the English language, spoken in England and southern and eastern Scotland in the early Middle Ages.
In chemistry, an organic compound is generally any chemical compound that contains carbon.
In biology, an organism (from Greek: ὀργανισμός, organismos) is any individual entity that exhibits the properties of life.
An organization or organisation is an entity comprising multiple people, such as an institution or an association, that has a collective goal and is linked to an external environment.
Oxygen is a chemical element with symbol O and atomic number 8.
The oxygen cycle is the biogeochemical cycle of oxygen within its four main reservoirs: the atmosphere (air), the total content of biological matter within the biosphere (the global sum of all ecosystems), the hydrosphere (the combined mass of water found on, under, and over the surface of planet Earth), and the lithosphere/Earth's crust.
The ozone layer or ozone shield is a region of Earth's stratosphere that absorbs most of the Sun's ultraviolet radiation.
The Pacific Ocean is the largest and deepest of Earth's oceanic divisions.
A park is an area of natural, semi-natural or planted space set aside for human enjoyment and recreation or for the protection of wildlife or natural habitats.
In science and engineering, the parts-per notation is a set of pseudo-units to describe small values of miscellaneous dimensionless quantities, e.g. mole fraction or mass fraction.
The pedosphere (from Greek πέδον pedon "soil" or "earth" and σφαῖρα sphaira "sphere") is the outermost layer of the Earth that is composed of soil and subject to soil formation processes.
A phenomenon (Greek: φαινόμενον, phainómenon, from the verb phainein, to show, shine, appear, to be manifest or manifest itself, plural phenomena) is any thing which manifests itself.
Philosophy (from Greek φιλοσοφία, philosophia, literally "love of wisdom") is the study of general and fundamental problems concerning matters such as existence, knowledge, values, reason, mind, and language.
Phosphorus is a chemical element with symbol P and atomic number 15.
The phosphorus cycle is the biogeochemical cycle that describes the movement of phosphorus through the lithosphere, hydrosphere, and biosphere.
Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that can later be released to fuel the organisms' activities (energy transformation).
A photovoltaic system, also PV system or solar power system, is a power system designed to supply usable solar power by means of photovoltaics.
Physics (from knowledge of nature, from φύσις phýsis "nature") is the natural science that studies matterAt the start of The Feynman Lectures on Physics, Richard Feynman offers the atomic hypothesis as the single most prolific scientific concept: "If, in some cataclysm, all scientific knowledge were to be destroyed one sentence what statement would contain the most information in the fewest words? I believe it is that all things are made up of atoms – little particles that move around in perpetual motion, attracting each other when they are a little distance apart, but repelling upon being squeezed into one another..." and its motion and behavior through space and time and that studies the related entities of energy and force."Physical science is that department of knowledge which relates to the order of nature, or, in other words, to the regular succession of events." Physics is one of the most fundamental scientific disciplines, and its main goal is to understand how the universe behaves."Physics is one of the most fundamental of the sciences. Scientists of all disciplines use the ideas of physics, including chemists who study the structure of molecules, paleontologists who try to reconstruct how dinosaurs walked, and climatologists who study how human activities affect the atmosphere and oceans. Physics is also the foundation of all engineering and technology. No engineer could design a flat-screen TV, an interplanetary spacecraft, or even a better mousetrap without first understanding the basic laws of physics. (...) You will come to see physics as a towering achievement of the human intellect in its quest to understand our world and ourselves."Physics is an experimental science. Physicists observe the phenomena of nature and try to find patterns that relate these phenomena.""Physics is the study of your world and the world and universe around you." Physics is one of the oldest academic disciplines and, through its inclusion of astronomy, perhaps the oldest. Over the last two millennia, physics, chemistry, biology, and certain branches of mathematics were a part of natural philosophy, but during the scientific revolution in the 17th century, these natural sciences emerged as unique research endeavors in their own right. Physics intersects with many interdisciplinary areas of research, such as biophysics and quantum chemistry, and the boundaries of physics are not rigidly defined. New ideas in physics often explain the fundamental mechanisms studied by other sciences and suggest new avenues of research in academic disciplines such as mathematics and philosophy. Advances in physics often enable advances in new technologies. For example, advances in the understanding of electromagnetism and nuclear physics led directly to the development of new products that have dramatically transformed modern-day society, such as television, computers, domestic appliances, and nuclear weapons; advances in thermodynamics led to the development of industrialization; and advances in mechanics inspired the development of calculus.
Physiology is the scientific study of normal mechanisms, and their interactions, which work within a living system.
In meteorology the planetary boundary layer (PBL), also known as the atmospheric boundary layer (ABL), is the lowest part of the atmosphere.
Plants are mainly multicellular, predominantly photosynthetic eukaryotes of the kingdom Plantae.
Plate tectonics (from the Late Latin tectonicus, from the τεκτονικός "pertaining to building") is a scientific theory describing the large-scale motion of seven large plates and the movements of a larger number of smaller plates of the Earth's lithosphere, since tectonic processes began on Earth between 3 and 3.5 billion years ago.
Politics (from Politiká, meaning "affairs of the cities") is the process of making decisions that apply to members of a group.
Pollen is a fine to coarse powdery substance comprising pollen grains which are male microgametophytes of seed plants, which produce male gametes (sperm cells).
A pollutant is a substance or energy introduced into the environment that has undesired effects, or adversely affects the usefulness of a resource.
Pollution is the introduction of contaminants into the natural environment that cause adverse change.
A pond is a body of standing water, either natural or artificial, that is usually smaller than a lake.
In meteorology, precipitation is any product of the condensation of atmospheric water vapor that falls under gravity.
A protist is any eukaryotic organism that has cells with nuclei and is not an animal, plant or fungus.
Public transport (also known as public transportation, public transit, or mass transit) is transport of passengers by group travel systems available for use by the general public, typically managed on a schedule, operated on established routes, and that charge a posted fee for each trip.
Rachel Louise Carson (May 27, 1907 – April 14, 1964) was an American marine biologist, author, and conservationist whose book Silent Spring and other writings are credited with advancing the global environmental movement.
In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium.
Radioactive decay (also known as nuclear decay or radioactivity) is the process by which an unstable atomic nucleus loses energy (in terms of mass in its rest frame) by emitting radiation, such as an alpha particle, beta particle with neutrino or only a neutrino in the case of electron capture, gamma ray, or electron in the case of internal conversion.
A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is an atom that has excess nuclear energy, making it unstable.
Rain is liquid water in the form of droplets that have condensed from atmospheric water vapor and then becomes heavy enough to fall under gravity.
Recreation is an activity of leisure, leisure being discretionary time.
Recycling is the process of converting waste materials into new materials and objects.
Renewable energy is energy that is collected from renewable resources, which are naturally replenished on a human timescale, such as sunlight, wind, rain, tides, waves, and geothermal heat.
Reproduction (or procreation or breeding) is the biological process by which new individual organisms – "offspring" – are produced from their "parents".
Reuse is the action or practice of using something again, whether for its original purpose (conventional reuse) or to fulfil a different function (creative reuse or repurposing).
A rheid is a substance whose temperature is below the melting point and whose deformation by viscous flow during the time of observation is at least three orders of magnitude (1,000×) greater than the elastic deformation under the given conditions.
A rift zone is a feature of some volcanoes, especially shield volcanoes, in which a linear series of cracks (or rifts) develops in a volcanic edifice, typically forming into two or three well-defined regions along the flanks of the vent.
Rock or stone is a natural substance, a solid aggregate of one or more minerals or mineraloids.
Salinity is the saltiness or amount of salt dissolved in a body of water (see also soil salinity).
A savanna or savannah is a mixed woodland grassland ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close.
R. P. Feynman, The Feynman Lectures on Physics, Vol.1, Chaps.1,2,&3.
A sea is a large body of salt water that is surrounded in whole or in part by land.
Sea spray refers to aerosol particles that are formed directly from the ocean, mostly by ejection into the atmosphere by bursting bubbles at the air-sea interface.
The seabed (also known as the seafloor, sea floor, or ocean floor) is the bottom of the ocean.
Seawater, or salt water, is water from a sea or ocean.
Sociology is the scientific study of society, patterns of social relationships, social interaction, and culture.
Soil is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life.
Soil biology is the study of microbial and faunal activity and ecology in soil.
Soil structure describes the arrangement of the solid parts of the soil and of the pore space located between them.
A solar pond is a large scale solar thermal collector with an integrated arrangement for storage of heated water.
The Southern Ocean, also known as the Antarctic Ocean or the Austral Ocean, comprises the southernmost waters of the World Ocean, generally taken to be south of 60° S latitude and encircling Antarctica.
In biology, a species is the basic unit of classification and a taxonomic rank, as well as a unit of biodiversity, but it has proven difficult to find a satisfactory definition.
In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions.
A spring is any natural situation where water flows from an aquifer to the Earth's surface.
In physiology, a stimulus (plural stimuli) is a detectable change in the internal or external environment.
The stratopause (formerly Mesopeak) is the level of the atmosphere which is the boundary between two layers: the stratosphere and the mesosphere.
The stratosphere is the second major layer of Earth's atmosphere, just above the troposphere, and below the mesosphere.
A stream is a body of water with surface water flowing within the bed and banks of a channel.
A stream bed is the channel bottom of a stream or river, the physical confine of the normal water flow.
A stream pool, in hydrology, is a stretch of a river or stream in which the water depth is above average and the water velocity is below average.
Subduction is a geological process that takes place at convergent boundaries of tectonic plates where one plate moves under another and is forced or sinks due to gravity into the mantle.
Sulfur or sulphur is a chemical element with symbol S and atomic number 16.
Sulfur dioxide (also sulphur dioxide in British English) is the chemical compound with the formula.
Sunlight is a portion of the electromagnetic radiation given off by the Sun, in particular infrared, visible, and ultraviolet light.
Surface runoff (also known as overland flow) is the flow of water that occurs when excess stormwater, meltwater, or other sources flows over the Earth's surface.
In chemistry, a suspension is a heterogeneous mixture that contains solid particles sufficiently large for sedimentation.
Sustainability is the process of change, in which the exploitation of resources, the direction of investments, the orientation of technological development and institutional change are all in harmony and enhance both current and future potential to meet human needs and aspirations.
Sustainable agriculture is farming in sustainable ways based on an understanding of ecosystem services, the study of relationships between organisms and their environment.
Temperature is a physical quantity expressing hot and cold.
The thermosphere is the layer of the Earth's atmosphere directly above the mesosphere and below the exosphere.
Tide pools or rock pools are shallow pools of seawater that form on the rocky intertidal shore.
Time is the indefinite continued progress of existence and events that occur in apparently irreversible succession from the past through the present to the future.
The timeline lists events in the external environment that have influenced events in human history.
A toxicant (pronounced TOK-sih-kunt) is any toxic substance.
The tropopause is the boundary in the Earth's atmosphere between the troposphere and the stratosphere.
The troposphere is the lowest layer of Earth's atmosphere, and is also where nearly all weather conditions take place.
In fluid dynamics, turbulence or turbulent flow is any pattern of fluid motion characterized by chaotic changes in pressure and flow velocity.
Ultraviolet (UV) is electromagnetic radiation with a wavelength from 10 nm to 400 nm, shorter than that of visible light but longer than X-rays.
The United Nations Framework Convention on Climate Change (UNFCCC) is an international environmental treaty adopted on 9 May 1992 and opened for signature at the Earth Summit in Rio de Janeiro from 3 to 14 June 1992.
An urban area is a human settlement with high population density and infrastructure of built environment.
Volcanic ash consists of fragments of pulverized rock, minerals and volcanic glass, created during volcanic eruptions and measuring less than 2 mm (0.079 inches) in diameter.
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.
Waste management or waste disposal are all the activities and actions required to manage waste from its inception to its final disposal.
Waste minimisation is a set of processes and practices intended to reduce the amount of waste produced.
Waste-to-energy (WtE) or energy-from-waste (EfW) is the process of generating energy in the form of electricity and/or heat from the primary treatment of waste, or the processing of waste into a fuel source.
Water is a transparent, tasteless, odorless, and nearly colorless chemical substance that is the main constituent of Earth's streams, lakes, and oceans, and the fluids of most living organisms.
The water cycle, also known as the hydrological cycle or the hydrologic cycle, describes the continuous movement of water on, above and below the surface of the Earth.
Water gardens, also known as aquatic gardens, are a type of water feature.
Water stagnation occurs when water stops flowing.
A watercourse is the channel that a flowing body of water follows.
Weather is the state of the atmosphere, describing for example the degree to which it is hot or cold, wet or dry, calm or stormy, clear or cloudy.
Weather modification is the act of intentionally manipulating or altering the weather.
The Western Climate Initiative, or WCI, was started in February 2007 by the governors of five western U.S. states (Arizona, California, New Mexico, Oregon, and Washington) with the goal of developing a multi-sector, market-based program to reduce greenhouse gas emissions.
Wilderness or wildland is a natural environment on Earth that has not been significantly modified by human activity.
A wildflower (or wild flower) is a flower that grows in the wild, meaning it was not intentionally seeded or planted.
Wildlife traditionally refers to undomesticated animal species, but has come to include all plants, fungi, and other organisms that grow or live wild in an area without being introduced by humans.
A wildlife corridor, habitat corridor, or green corridor is an area of habitat connecting wildlife populations separated by human activities or structures (such as roads, development, or logging).
Wildness, in its literal sense, is the quality of being wild or untamed.
Wind is the flow of gases on a large scale.
Wladimir Peter Köppen (Влади́мир Петро́вич Кёппен, Vladimir Petrovich Kyoppen; 7 October 1846 – 22 June 1940) was a Russian-German geographer, meteorologist, climatologist and botanist.
The World Ocean or Global Ocean (colloquially the sea or the ocean) is the interconnected system of Earth's oceanic waters, and comprises the bulk of the hydrosphere, covering (70.8%) of Earth's surface, with a total volume of.
Zero Waste is a philosophy that encourages the redesign of resource life cycles so that all products are reused.
1,000,000,000 (one billion, short scale; one thousand million or milliard, yard, long scale) is the natural number following 999,999,999 and preceding 1,000,000,001.