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"Land management has preserved the natural characteristics of "Hopetoun Falls, "Australia while allowing ample access for visitors.
Satellite image of the "Sahara desert; the world's largest hot desert and third-largest desert after the "polar deserts.

The natural environment encompasses all "living and non-living things occurring "naturally, meaning in this case not "artificial. The term is most often applied to the "Earth or some parts of Earth. This environment encompasses the interaction of all living "species, "climate, weather, and natural resources that affect human survival and economic activity. [1] The concept of the natural environment can be distinguished as components:

In contrast to the natural environment is the "built environment. In such areas where man has fundamentally transformed landscapes such as urban settings and agricultural "land conversion, the natural environment is greatly modified into a simplified human environment. Even acts which seem less extreme, such as building a mud "hut or a "photovoltaic system in the "desert, modify the natural environment into an artificial one. Though many animals build things to provide a better environment for themselves, they are not human, hence "beaver dams and the works of "Mound-building termites are thought of as natural.

People seldom find absolutely natural environments on Earth, and naturalness usually varies in a continuum, from 100% natural in one extreme to 0% natural in the other. More precisely, we can consider the different aspects or components of an environment, and see that their degree of naturalness is not uniform.[2] If, for instance, in an agricultural field, the "mineralogic composition and the "structure of its soil are similar to those of an undisturbed forest soil, but the structure is quite different.

Natural environment is often used as a synonym for "habitat. For instance, when we say that the natural environment of giraffes is the "savanna.



A "volcanic fissure and "lava channel.
"Earth's layered structure. (1) inner core; (2) outer core; (3) lower mantle; (4) upper mantle; (5) lithosphere; (6) crust

Earth science generally recognizes 4 spheres, the "lithosphere, the "hydrosphere, the "atmosphere, and the "biosphere[3] as correspondent to "rocks, "water, "air, and "life respectively. Some scientists include, as part of the spheres of the Earth, the "cryosphere (corresponding to "ice) as a distinct portion of the hydrosphere, as well as the "pedosphere (corresponding to "soil) as an active and intermixed sphere. "Earth science (also known as geoscience, the geosciences or the Earth Sciences), is an all-embracing term for the "sciences related to the planet "Earth.[4] There are four major "disciplines in earth sciences, namely "geography, "geology, "geophysics and "geodesy. These major disciplines use "physics, "chemistry, "biology, "chronology and "mathematics to build a qualitative and quantitative understanding of the principal areas or "spheres of Earth.

Geological activity[edit]

The Earth's "crust, or "lithosphere, is the outermost solid surface of the planet and is chemically and mechanically different from underlying "mantle. It has been generated greatly by "igneous processes in which "magma cools and solidifies to form solid rock. Beneath the lithosphere lies the mantle which is heated by the "decay of "radioactive elements. The mantle though solid is in a state of "rheic "convection. This convection process causes the lithospheric plates to move, albeit slowly. The resulting process is known as "plate tectonics. "Volcanoes result primarily from the melting of "subducted crust material or of rising mantle at "mid-ocean ridges and "mantle plumes.

Water on Earth[edit]

"Coral reefs have significant marine "biodiversity.

Most water is found in one or another natural kind of "body of water.


An "ocean is a major body of "saline water, and a component of the hydrosphere. Approximately 71% of the Earth's "surface (an area of some 362 million square kilometers) is covered by ocean, a "continuous body of water that is customarily divided into several principal oceans and smaller "seas. More than half of this area is over 3,000 meters (9,800 ft) deep. Average oceanic "salinity is around 35 "parts per thousand (ppt) (3.5%), and nearly all seawater has a salinity in the range of 30 to 38 ppt. Though generally recognized as several 'separate' oceans, these waters comprise one global, interconnected body of salt water often referred to as the "World Ocean or global ocean.[5][6] The deep "seabeds are more than half the Earth's surface, and are among the least-modified natural environments. The major oceanic divisions are defined in part by the "continents, various "archipelagos, and other criteria: these divisions are (in descending order of size) the "Pacific Ocean, the "Atlantic Ocean, the "Indian Ocean, the "Southern Ocean and the "Arctic Ocean.


The "Columbia River, along the border of the U.S. states of "Oregon and "Washington.

A river is a natural "watercourse,[7] usually "freshwater, flowing toward an "ocean, a "lake, a "sea or another river. A few rivers simply flow into the ground and dry up completely before reaching another body of water.

Rocky stream in the U.S. state of "Hawaii

The water in a river is usually in a "channel, made up of a "stream bed between "banks. In larger rivers there is also a wider "floodplain shaped by waters over-topping the channel. Flood plains may be very wide in relation to the size of the river channel. Rivers are a part of the "hydrological cycle. Water within a river is generally collected from "precipitation through "surface runoff, "groundwater recharge, "springs, and the release of water stored in "glaciers and snowpacks.

Small rivers may also be termed by several other names, including "stream, creek and brook. Their "current is confined within a "bed and "stream banks. Streams play an important "corridor role in connecting "fragmented habitats and thus in conserving "biodiversity. The study of streams and waterways in general is known as surface "hydrology.[8]


"Lácar Lake, of "glacial origin, in the "province of "Neuquén, "Argentina.

A lake (from Latin lacus) is a "terrain feature, a body of water that is localized to the bottom of "basin. A body of water is considered a lake when it is inland, is not part of an "ocean, and is larger and deeper than a "pond.[9][10]


Natural lakes on Earth are generally found in "mountainous areas, "rift zones, and areas with ongoing or recent "glaciation. Other lakes are found in "endorheic basins or along the courses of mature rivers. In some parts of the world, there are many lakes because of chaotic drainage patterns left over from the last "Ice Age. All lakes are temporary over geologic time scales, as they will slowly fill in with sediments or spill out of the basin containing them.


A pond is a "body of "standing water, either natural or man-made, that is usually smaller than a "lake. A wide variety of man-made bodies of water are classified as ponds, including "water gardens designed for aesthetic ornamentation, "fish ponds designed for commercial fish breeding, and "solar ponds designed to store thermal energy. Ponds and lakes are distinguished from streams by their "current speed. While currents in streams are easily observed, ponds and lakes possess thermally driven micro-currents and moderate wind driven currents. These features distinguish a pond from many other aquatic terrain features, such as "stream pools and "tide pools.

Atmosphere, climate and weather[edit]

Atmospheric gases "scatter blue light more than other wavelengths, creating a blue "halo when seen from space.
A view of Earth's "troposphere from an "airplane.
"Lightning is an "atmospheric discharge of "electricity accompanied by "thunder, which occurs during "thunderstorms and certain other natural conditions.[11]

The atmosphere of the Earth serves as a key factor in sustaining the planetary ecosystem. The thin layer of "gases that envelops the Earth is held in place by the planet's gravity. Dry "air consists of 78% "nitrogen, 21% "oxygen, 1% "argon and other "inert gases, such as "carbon dioxide. The remaining gases are often referred to as trace gases,[12] among which are the "greenhouse gases such as water vapor, carbon dioxide, methane, nitrous oxide, and ozone. Filtered air includes trace amounts of many other "chemical compounds. Air also contains a variable amount of "water vapor and "suspensions of water droplets and "ice crystals seen as "clouds. Many natural substances may be present in tiny amounts in an unfiltered air sample, including "dust, "pollen and "spores, "sea spray, "volcanic ash, and "meteoroids. Various industrial "pollutants also may be present, such as "chlorine (elementary or in compounds), "fluorine compounds, elemental "mercury, and "sulphur compounds such as "sulphur dioxide [SO2].

The "ozone layer of the Earth's atmosphere plays an important role in depleting the amount of "ultraviolet (UV) radiation that reaches the surface. As "DNA is readily damaged by UV light, this serves to protect life at the surface. The atmosphere also retains heat during the night, thereby reducing the daily temperature extremes.

Atmospheric layers[edit]

Principal layers[edit]

Earth's atmosphere can be divided into five main layers. These layers are mainly determined by whether temperature increases or decreases with altitude. From highest to lowest, these layers are:

Other layers

Within the five principal layers determined by temperature are several layers determined by other properties.

Effects of global warming[edit]

The Retreat of glaciers since 1850 of "Aletsch Glacier in the "Swiss Alps (situation in 1979, 1991 and 2002), due to "global warming.

The potential dangers of "global warming are being increasingly studied by a wide global consortium of scientists. These scientists are increasingly concerned about the potential long-term effects of global warming on our natural environment and on the planet. Of particular concern is how "climate change and global warming caused by "anthropogenic, or human-made releases of "greenhouse gases, most notably "carbon dioxide, can act interactively, and have adverse effects upon the planet, its natural environment and humans' existence. It is clear the planet is warming, and warming rapidly.–This warming is also responsible for the extinction of natural habitats, which in turn leads to a reduction in wildlife population.The most recent report from the Intergovernmental Panel on Climate Change (the group of the leading climate scientists in the world) concluded that the earth will warm anywhere from 2.7 to almost 11 degrees Fahrenheit (1.5 to 6 degrees Celsius) between 1990 and 2100.[13] Efforts have been increasingly focused on the "mitigation of greenhouse gases that are causing climatic changes, on "developing adaptative strategies to global warming, to assist humans, other animal, and plant species, ecosystems, regions and "nations in adjusting to the "effects of global warming. Some examples of recent collaboration to address climate change and global warming include:

Another view of the "Aletsch Glacier in the "Swiss Alps and because of "global warming it has been decreasing

A significantly profound challenge is to identify the natural environmental dynamics in contrast to environmental changes not within natural variances. A common solution is to adapt a static view neglecting natural variances to exist. Methodologically, this view could be defended when looking at processes which change slowly and short time series, while the problem arrives when fast processes turns essential in the object of the study.


""Map of world dividing climate zones, largely influenced by latitude. The zones, going from the equator upward (and downward) are Tropical, Dry, Moderate, Continental and Polar. There are subzones within these zones.
Worldwide "climate classifications map

"Climate encompasses the statistics of "temperature, "humidity, "atmospheric pressure, "wind, "rainfall, atmospheric particle count and numerous other "meteorological elements in a given region over long periods of time.["citation needed] Climate can be contrasted to "weather, which is the present condition of these same elements over periods up to two weeks.["citation needed]

Climates can be "classified according to the average and typical ranges of different variables, most commonly temperature and precipitation. The most commonly used classification scheme is the one originally developed by "Wladimir Köppen. The Thornthwaite system,[17] in use since 1948, incorporates "evapotranspiration in addition to temperature and precipitation information and is used in studying animal species diversity and potential impacts of "climate changes.["citation needed]


"Rainbows are "optical and "meteorological phenomenon that causes a "spectrum of "light to appear in the sky when the Sun shines onto droplets of moisture in the "Earth's atmosphere.

"Weather is a set of all the "phenomena occurring in a given "atmospheric area at a given "time.[18] Most weather phenomena occur in the "troposphere,[19][20] just below the "stratosphere. Weather refers, generally, to day-to-day temperature and precipitation activity, whereas "climate is the term for the average atmospheric conditions over longer periods of time.[21] When used without qualification, "weather" is understood to be the weather of "Earth.

Weather occurs due to density (temperature and moisture) differences between one place and another. These differences can occur due to the sun angle at any particular spot, which varies by latitude from the tropics. The strong temperature contrast between polar and tropical air gives rise to the "jet stream. Weather systems in the "mid-latitudes, such as "extratropical cyclones, are caused by instabilities of the jet stream flow. Because the Earth's "axis is tilted relative to its orbital plane, "sunlight is incident at different angles at different times of the year. On the Earth's surface, temperatures usually range ±40 °C (100 °F to −40 °F) annually. Over thousands of years, changes in the Earth's orbit have affected the amount and distribution of solar energy received by the Earth and influence long-term climate

Surface "temperature differences in turn cause pressure differences. Higher altitudes are cooler than lower altitudes due to differences in compressional heating. Weather forecasting is the application of science and technology to predict the state of the "atmosphere for a future time and a given location. The "atmosphere is a "chaotic system, and small changes to one part of the system can grow to have large effects on the system as a whole. Human attempts to "control the weather have occurred throughout human history, and there is evidence that civilized human activity such as "agriculture and "industry has inadvertently modified weather patterns.


There are many "plant species on the planet.
An example of the many "animal species on the "Earth.

Evidence suggests that "life on Earth has existed for about 3.7 "billion years.[22] All known life forms share fundamental molecular mechanisms, and based on these observations, theories on the origin of life attempt to find a mechanism explaining the formation of a primordial single cell organism from which all life originates. There are many different hypotheses regarding the path that might have been taken from simple "organic molecules via pre-cellular life to protocells and metabolism.

Although there is no universal agreement on the definition of life, scientists generally accept that the biological manifestation of life is characterized by "organization, "metabolism, "growth, "adaptation, response to "stimuli and "reproduction.[23] Life may also be said to be simply the characteristic state of "organisms. In "biology, the science of living organisms, "life" is the condition which distinguishes active "organisms from "inorganic matter, including the capacity for growth, "functional activity and the continual change preceding death.[24][25]

A diverse variety of living organisms (life forms) can be found in the "biosphere on "Earth, and properties common to these organisms—"plants, "animals, "fungi, "protists, "archaea, and "bacteria—are a "carbon- and water-based "cellular form with complex "organization and heritable "genetic information. Living organisms undergo "metabolism, maintain "homeostasis, possess a capacity to "grow, respond to "stimuli, "reproduce and, through "natural selection, adapt to their environment in successive generations. More complex living organisms can communicate through various means.


"Rainforests often have a great deal of "biodiversity with many plant and animal species. This is the "Gambia River in "Senegal's "Niokolo-Koba National Park.

An "ecosystem (also called as environment) is a natural unit consisting of all plants, animals and micro-organisms ("biotic factors) in an area functioning together with all of the non-living physical ("abiotic) factors of the environment.[26]

Central to the ecosystem concept is the idea that "living organisms are continually engaged in a highly interrelated set of relationships with every other element constituting the "environment in which they exist. "Eugene Odum, one of the founders of the science of "ecology, stated: "Any unit that includes all of the organisms (ie: the "community") in a given area interacting with the physical environment so that a flow of energy leads to clearly defined trophic structure, biotic diversity, and material cycles (i.e.: exchange of materials between living and nonliving parts) within the system is an ecosystem."[27]

"Old-growth forest and a "creek on "Larch Mountain, in the U.S. state of "Oregon.

The human ecosystem concept is then grounded in the deconstruction of the human/nature "dichotomy, and the emergent premise that all species are ecologically integrated with each other, as well as with the abiotic constituents of their "biotope.

A greater number or variety of species or "biological diversity of an ecosystem may contribute to greater resilience of an ecosystem, because there are more species present at a location to respond to change and thus "absorb" or reduce its effects. This reduces the effect before the ecosystem's structure is fundamentally changed to a different state. This is not universally the case and there is no proven relationship between the species diversity of an ecosystem and its ability to provide goods and services on a sustainable level.

The term ecosystem can also pertain to human-made environments, such as "human ecosystems and human-influenced ecosystems, and can describe any situation where there is relationship between living organisms and their environment. Fewer areas on the surface of the earth today exist free from human contact, although some genuine "wilderness areas continue to exist without any forms of human intervention.


Map of Terrestrial "biomes classified by vegetation.

"Biomes are terminologically similar to the concept of ecosystems, and are "climatically and geographically defined areas of ecologically similar climatic conditions on the "Earth, such as "communities of "plants, "animals, and "soil organisms, often referred to as ecosystems. Biomes are defined on the basis of factors such as plant structures (such as trees, shrubs, and grasses), leaf types (such as broadleaf and needleleaf), plant spacing (forest, woodland, savanna), and climate. Unlike "ecozones, biomes are not defined by genetic, taxonomic, or historical similarities. Biomes are often identified with particular patterns of "ecological succession and "climax vegetation.

Biogeochemical cycles[edit]

"Chloroplasts conduct "photosynthesis and are found in "plant cells and other "eukaryotic organisms. These are Chloroplasts visible in the cells of Plagiomnium affine — Many-fruited Thyme-moss.

Global "biogeochemical cycles are critical to life, most notably those of "water, "oxygen, "carbon, "nitrogen and "phosphorus.[28]


The "Ahklun Mountains and the "Togiak Wilderness within the "Togiak National Wildlife Refuge in the U.S. state of "Alaska.

"Wilderness is generally defined as a natural environment on "Earth that has not been significantly modified by "human activity. The WILD Foundation goes into more detail, defining wilderness as: "The most intact, undisturbed wild natural areas left on our planet - those last truly wild places that humans do not control and have not developed with roads, pipelines or other industrial infrastructure."[29] Wilderness areas and protected "parks are considered important for the survival of certain "species, ecological studies, "conservation, solitude, and "recreation. Wilderness is deeply valued for cultural, spiritual, "moral, and "aesthetic reasons. Some nature writers believe wilderness areas are vital for the human spirit and creativity.[30]

The word, "wilderness", derives from the notion of "wildness; in other words that which is not controllable by humans. The word's "etymology is from the "Old English wildeornes, which in turn derives from wildeor meaning wild beast (wild + deor = beast, deer).[31] From this point of view, it is the wildness of a place that makes it a wilderness. The mere presence or activity of people does not disqualify an area from being "wilderness." Many ecosystems that are, or have been, inhabited or influenced by activities of people may still be considered "wild." This way of looking at wilderness includes areas within which natural processes operate without very noticeable human interference.

"Wildlife includes all non-"domesticated plants, animals and other organisms. Domesticating wild plant and animal species for human benefit has occurred many times all over the planet, and has a major impact on the environment, both positive and negative. Wildlife can be found in all ecosystems. Deserts, rain forests, plains, and other areas—including the most developed "urban sites—all have distinct forms of wildlife. While the term in popular culture usually refers to animals that are untouched by civilized human factors, most scientists agree that wildlife around the world is (now) impacted by human activities.

A view of "wilderness in Estonia


Before "flue-gas desulfurization was installed, the "air-polluting emissions from this power plant in "New Mexico contained excessive amounts of "sulfur dioxide
"Amazon Rainforest in "Brazil. The tropical rainforests of South America contain the largest diversity of species on Earth, including some that have evolved within the past few hundred thousand years.[32][33]

It is the common understanding of natural environment that underlies "environmentalism — a broad "political, "social, and "philosophical movement that advocates various actions and policies in the interest of protecting what nature remains in the natural environment, or restoring or expanding the role of nature in this environment. While true wilderness is increasingly rare, wild nature (e.g., unmanaged "forests, uncultivated "grasslands, "wildlife, "wildflowers) can be found in many locations previously inhabited by humans.

Goals for the benefit of people and natural systems, commonly expressed by "environmental scientists and "environmentalists include:


In some cultures the term environment is meaningless because there is no separation between people and what they view as the natural world, or their surroundings.[35] Specifically in the United States, many native cultures do not recognize the "environment", or see themselves as environmentalists.[36]

See also[edit]


  1. ^ Johnson, D. L.; Ambrose, S. H.; Bassett, T. J.; Bowen, M. L.; Crummey, D. E.; Isaacson, J. S.; Johnson, D. N.; Lamb, P.; Saul, M.; Winter-Nelson, A. E. (1997). "Meanings of Environmental Terms". Journal of Environmental Quality. 26 (3): 581–589. "doi:10.2134/jeq1997.00472425002600030002x. 
  2. ^ Symons, Donald (1979). The Evolution of Human Sexuality. New York: Oxford University Press. p. 31. "ISBN "0-19-502535-0. 
  3. ^ Earth's Spheres Archived 2007-08-31 at the "Wayback Machine.. ©1997-2000. Wheeling Jesuit University/NASA Classroom of the Future. Retrieved November 11, 2007.
  4. ^ Wordnet Search: Earth science["dead link]
  5. ^ ""Archived copy". Archived from the original on 2012-07-14. Retrieved 2012-07-15. ". The Columbia Encyclopedia. 2002. New York: Columbia University Press
  6. ^ "Distribution of land and water on the planet Archived May 31, 2008, at the "Wayback Machine.". UN Atlas of the Oceans Archived September 15, 2008, at the "Wayback Machine.
  7. ^ River {definition} from Merriam-Webster. Accessed February 2010.
  8. ^ http://ga.water.usgs.gov/edu/hydrology.html/ Archived August 13, 2009, at the "Wayback Machine.
  9. ^ Britannica Online. "Lake (physical feature)". Retrieved 2008-06-25. [a Lake is] any relatively large body of slowly moving or standing water that occupies an inland basin of appreciable size. Definitions that precisely distinguish lakes, ponds, swamps, and even rivers and other bodies of nonoceanic water are not established. It may be said, however, that rivers and streams are relatively fast moving; marshes and swamps contain relatively large quantities of grasses, trees, or shrubs; and ponds are relatively small in comparison to lakes. Geologically defined, lakes are temporary bodies of water. 
  10. ^ "Dictionary.com definition". Retrieved 2008-06-25. a body of fresh or salt water of considerable size, surrounded by land. 
  11. ^ NGDC - NOAA. "Volcanic Lightning". National Geophysical Data Center - NOAA. Retrieved September 21, 2007. 
  12. ^ Joe Buchdahl. "Atmosphere, Climate & Environment Information Programme". Ace.mmu.ac.uk. Archived from the original on 2010-10-09. Retrieved 2013-03-09. 
  13. ^ Forthofer, Ron. "It's Time To Act On Global Warming". Boulder Daily Camera. Archived from the original on 2013-06-16. Retrieved 2013-10-28. 
  14. ^ United Nations Framework Convention on Climate Change Retrieved August 2008.
  15. ^ Kyoto Protocol from United Nations Framework Convention on Climate Change, Retrieved August 2008.
  16. ^ Western Climate Initiative, Retrieved on Feb 12, 2009.
  17. ^ "C. W. Thornthwaite, "An Approach Toward a Rational Classification of Climate", Geographical Review, 38:55-94, 1948
  18. ^ Merriam-Webster Dictionary. Weather. Retrieved on 2008-06-27.
  19. ^ Glossary of Meteorology. Hydrosphere. Archived 2012-03-15 at the "Wayback Machine. Retrieved on 2008-06-27.
  20. ^ Glossary of Meteorology. Troposphere. Archived 2012-09-28 at the "Wayback Machine. Retrieved on 2008-06-27.
  21. ^ "Climate". Glossary of Meteorology. "American Meteorological Society. Retrieved 2008-05-14. 
  22. ^ "History of life through time". University of California Museum of Paleontology.
  23. ^ "Definition of Life". California Academy of Sciences. 2006. Archived from the original on 2007-02-08. Retrieved 2007-01-07. 
  24. ^ The Concise Oxford Dictionary. English Edition 1991
  25. ^ "Merriam-Webster Dictionary". Merriam-Webster Dictionary. Retrieved 2009-06-21. 
  26. ^ Christopherson, Robert W. (1996). Geosystems: An Introduction to Physical Geography. Prentice Hall. "ISBN "0-13-505314-5. 
  27. ^ Odum, E. P. (1971). Fundamentals of Ecology (Third ed.). New York: Saunders. "ISBN "0-7216-6941-7. 
  28. ^ Smil, V. (2000). Cycles of Life. New York: Scientific American Library. "ISBN "978-0-7167-5079-6.
  29. ^ "The WILD Foundation". Wild.org. Archived from the original on 2012-12-04. Retrieved 2013-03-09. 
  30. ^ No Man's Garden by Daniel B. Botkin p155-157
  31. ^ wilderness. CollinsDictionary.com. Collins English Dictionary - Complete & Unabridged 11th Edition. Retrieved November 29, 2012.
  32. ^ "Why the Amazon Rainforest is So Rich in Species : News". Earthobservatory.nasa.gov. 2005-12-05. Archived from the original on 2011-02-25. Retrieved 2013-03-09. 
  33. ^ "Why The Amazon Rainforest Is So Rich In Species". Sciencedaily.com. 2005-12-05. Retrieved 2013-03-09. 
  34. ^ Escolero, O.; Kralisch, S.; Martínez, S.E.; Perevochtchikova, M. (2016). "Diagnóstico y análisis de los factores que influyen en la vulnerabilidad de las fuentes de abastecimiento de agua potable a la Ciudad de México, México" (PDF). Boletín de la Sociedad Geológica Mexicana (in Spanish). 68 (3): 409–427. 
  35. ^ Jamieson, Dale. (2007). The Heart of Environmentalism. In R. Sandler & P. C. Pezzullo. Environmental Justice and Environmentalism. (pp. 85-101). Massachusetts Institute of Technology Press.
  36. ^ Davis, T. (2000). Sustaining the Forest, the People, and the Spirit. (pp. 1-24). State University of New York.

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