| A | B |
|---|
| carrying capacity | the maximum number of individuals of a particular species that an environment can support |
| population | the introduction of harmful substances into an environment |
| population explosion | a large increase in population of a species, due to a rapid increase in birthrate, or a sharply reduced death rate, or both |
| landfill | an area of land where waste is deposited |
| sanitary landfill | a waste-disposal area that is excavated; lined with plastic, concrete, or clay; and filled with layers of waste and dirt |
| hazardous waste | waste that is dangerous to organisms because it is poisonous, cancer causing, or radioactive |
| conservation | the careful use of resources to avoid wasting them and damaging the environment; includes reusing and recycling resources |
| composing | the piling up of grass clippings, dead leaves, and other organic matter so they can gradually decompose |
| recyclable | items that can be processed and used again |
| photochemical smog | a brown-colored air pollution that forms when sunlight chemically changes the pollutants released into the air by burning fossil fuels |
| sulfurous smog | a gray-colored air pollution created when power plants and home furnaces burn fossil fuels, releasing sulfur compounds and smoke particles into the air |
| acid ran | acidic rain, snow, sleet, or hail that can form when sulfur dioxide (from coal-burning power plants) and nitrogen oxide (from car exhausts) combine with moisture in the air |
| pH scale | a logaritmic scale used to describe how acidic or how basic a solution is; an abbreviation of potential of Hydrogen |
| acid | any substance with a pH lower than seven; the lower the pH number, the greater the acidity |
| base | any substance with a pH above seven; the higher the pH number, the more basic the solution |
| Clean Air Act | this 1990 US law sets a maximum level for major air pollutants |
| scrubber | a device that "scrubs" the smoke from coal-burning power plants with basic compounds to increase the pH to a safe level |
| Safe Drinking Water Act | this 1986 law sets safety standards for drinking water in the US |
| Clean Water Act | this 1990 US law sets a maximum level for major air pollutants |
