Land, Air and Water Pollution

Photochemical smog is a mixture of pollutants that are formed when nitrogen oxides and volatile organic compounds react to sunlight, creating a brownish haze.

A reservoir is a large natural or artificial lake created to store water for human use, such as drinking water supply, irrigation, or hydroelectric power.

Sewage refers to the wastewater and excreta conveyed in sewers. It originates from domestic, commercial, and industrial sources.

The topsoil, or A horizon, is the uppermost layer of mineral soil that contains high amounts of organic matter, making it the most fertile layer for plant growth. Litter is organic debris on top, while subsoil and bedrock lie deeper.

Radon is a radioactive, colorless, odorless noble gas that occurs naturally as a decay product of uranium in rocks and soil.

About 97% of Earth's water is salt water in oceans, leaving only about 3% as fresh water, much of which is locked in ice caps and glaciers.

A point source of pollution is a single, identifiable source, such as a pipe or a specific spill. Oil spills from tankers are classic examples of point source pollution.

Tributaries are smaller streams or rivers that flow into a larger main river or lake. Watersheds are the land areas that drain into a body of water.

Technology like catalytic converters and scrubbers is primarily used to reduce the amount of pollutants emitted into the air from industrial or vehicle sources.

Acid rain is primarily caused by emissions of sulfur dioxide and nitrogen oxides, which react with water vapor in the atmosphere to form sulfuric and nitric acids.

When vegetation is removed through logging or farming, the soil is no longer held in place by roots, making it susceptible to being carried away by wind or water, which is erosion.

Agriculture is the practice of farming, including the cultivation of soil for the growing of crops and the rearing of animals to provide food and other products.

Bogs are a type of wetland characterized by acidic water, peat deposits, and mosses. They are distinct from marshes and swamps.

A swamp is a forested wetland, often described as a flooded forest, where trees and shrubs can grow in saturated soil.

Proper treatment of sewage removes contaminants from wastewater before it is released into the environment, significantly reducing water pollution.

An artesian well is a well where water rises to the surface under its own pressure because the aquifer is trapped between impermeable layers.

Eutrophication is the process by which a body of water becomes overly enriched with nutrients, leading to excessive plant growth and decay, which eventually depletes oxygen and fills the lake.

Chlorofluorocarbons (CFCs) are synthetic compounds that rise to the stratosphere and break down ozone molecules through catalytic reactions. This disrupts the natural ozone cycle and causes the ozone hole, particularly over Antarctica.

Urbanization involves replacing natural land cover with buildings and pavement, which is a direct impact on land use.