Natural environment

The natural environment, commonly referred to simply as the environment, is a term that comprises all living and non-living things that occur naturally on Earth or some part of it (e.g. the natural environment in a country). This term includes a few key components:
Complete landscape units that function as natural systems without massive human intervention, including all plants, animals, rocks, etc. and natural phenomena that occur within their boundaries. Universal natural resources and physical phenomena that lack clear-cut boundaries, such as air, water, and climate, as well as energy, radiation, electric charge, and magnetism, not originating from human activity. The natural environment is contrasted with the built environment, which comprises the areas and components that are heavily influenced by man. A geographical area is regarded as a natural environment (with an indefinite article), if the human impact on it is kept under a certain limited level (similar to section 1 above). This level depends on the specific context, and changes in different areas and contexts. The term wilderness, on the other hand, refers to areas without any human intervention whatsoever (or almost so).
[edit] ChallengesIt 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 commonly expressed by environmentalists include reduction and clean up of man-made pollution, with future goals of zero pollution; reducing societal consumption of non-renewable fuels; development of alternative, green, low-carbon or renewable energy sources; conservation and sustainable use of scarce resources such as water, land, and air; protection of representative or unique or pristine ecosystems; preservation and expansion of threatened or endangered species or ecosystems from extinction; the establishment of nature and biosphere reserves under various types of protection; and, most generally, the protection of biodiversity and ecosystems upon which all human and other life on earth depends.
More recently, there has been a strong concern about climate change such as global warming caused by anthropogenic releases of greenhouse gases, most notably carbon dioxide, and their interactions with humans and the natural environment. Efforts here have focused on the mitigation of greenhouse gases that are causing climatic changes (e.g. through the Climate Change Convention and the Kyoto Protocol), and on developing adaptative strategies to assist species, ecosystems, humans, regions and nations in adjusting to the Effects of global warming.
A more profound challenge, however, 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.

Pollution by Petroleum

Environmental Pollution
Petroleum-derived contaminants constitute one of the most prevalent sources of environmental degradation in the industrialized world. In large concentrations, the hydrocarbon molecules that make up crude oil and petroleum products are highly toxic to many organisms, including humans. Petroleum also contains trace amounts of sulfur and nitrogen compounds, which are dangerous by themselves and can react with the environment to produce secondary poisonous chemicals. The dominance of petroleum products in the United States and the world economy creates the conditions for distributing large amounts of these toxins into populated areas and ecosystems around the globe.

Smoke is pouring from a refinery burnoff vent. (
© Royalty-Free/Corbis. Reproduced by permission.)
Oil Spills
Perhaps the most visible source of petroleum pollution are the catastrophic oil-tanker spills—like the 1989 Exxon Valdez spill in Prince William Sound, Alaska—that make news headlines and provide disheartening pictures of oilcoated shorelines and dead or oiled birds and sea animals. These spills occur during the transportation of crude oil from exporting to importing nations. Crude oil travels for long distances by either ocean tanker or land pipeline, and both methods are prone to accidents. Oil may also spill at the site where it is extracted, as in the case of a blowout like the Ixtoc I exploratory well in 1979 (see table "Ten Largest Oil Spills in History"). A blowout is one of the major risks of drilling for oil. It occurs when gas trapped inside the deposit is at such a high pressure that oil suddenly erupts out of the drill shaft in a geyser.
Accidents with tankers, pipelines, and oil wells release massive quantities of petroleum into land and marine ecosystems in a concentrated form. The ecological impacts of large spills like these have only been studied for a very

World Oil Price 1970-2000 (
World Oil Market and Price Chronologies DOE Energy Information Administration; originally published by the Department of Energy's Office of the Strategic Petroleum Reserve, Analysis Division) few cases, and it is not possible to say which have been the most environmentally damaging accidents in history. A large oil spill in the open ocean may do less harm to marine organisms than a small spill near the shore. The Exxon Valdez disaster created a huge ecological disaster not because of the volume of oil spilled (eleven million gallons) but because of the amount of shoreline affected, the sensitivity and abundance of organisms in the area, and the physical characteristics of the Prince William Sound, which helped to amplify the damage. The Exxon Valdez spill sparked the most comprehensive and costly cleanup effort ever attempted, and called more public attention to oil accidents than ever before. Scientific studies of the effects of oil in Prince William Sound are ongoing, and the number of tanker accidents worldwide has decreased significantly since the time of the Valdez spill, due to stricter regulations and such required improvements in vessel design as double-hull construction.