The Ecosystem The interrelationships between all living things and the environment. Emphasis is on interdependence of all things. People, nature, and the earth form a delicately balanced system. Ozone is a rare form of oxygen that is poisonous to human beings at ground level but is necessary in the upper atmosphere to absorb the deadly ultraviolet radiation of the sun.
Environmental Pollution Pollution is the harmful alteration of our environment by our own actions. Pollutants – either unwanted by- products or our activities or the obnoxious residues of things we have made, used, and thrown away. Air Pollution Water Pollution Land Pollution Global Warming Noise Pollution Aesthetic Damage
Types of Pollution Air pollution Most air pollution is caused by the burning of fossil fuels. Water pollution Organic sewage Eutrophication Infectious agents Organic chemicals Inorganic and miscellaneous chemicals Sediments from land corrosion Radioactive substances Waste heat from power plants and industry
Pesticides – chemicals used to kill insects defined as pests. Herbicides – chemicals used to kill plant life, particularly weeds. Chemical wastes Radioactive fallout Acid rain Garbage Global warming Since the late 1800’s the average global surface temperature has increased about 0.75 degrees C. Most warming has occurred since 1950.
Environmental Depletion The Dwindling Natural Resources No nation is self-sufficient in the modern world. Energy Production and Consumption Energy consumption per capita is higher in the United States than it is in any other country in the world. Consumption is growing more rapidly than production.
Environmental Pollution Problems Enforcement of air pollution standards has been reducing the amount of pollutants released into the air. In 2002, 34.3% of children under the age of 18 lived in an area that did not meet one or more of the air quality standards. Sick building syndrome. Presence of radon gas Electromagnetic radiation In 2000, 39% of rivers and streams; 45% of lakes, reservoirs, and ponds; 78% of the Great Lakes shoreline; and 14% of ocean shoreline were polluted.
The Physical Threat Air pollution can cause or contribute to: Permanent lung damage in children Fetal deaths Infant mortality Respiratory illness Cardiovascular disease Skin problems, ulcers, and liver and kidney damage Premature deaths Asthma attacks Lung cancer
Exposure to toxic materials can also lead to sterility The depleted ozone layer raises the risk of skin cancer
Threat to the Ecological Balance A number of species of animals and plants have disappeared. People depend on biological diversity for the quality of their lives. Photosynthesis – a natural process essential to life, resulting in the production of oxygen and organic materials. Urbanization – the increasing concentration of people living in cities.