chapter 19.3
DESCRIPTION
Chapter 19.3. Pollution and Recycling. What Causes Pollution?. Pollution is the contamination of air, water, or soil. What Causes Pollution?. Pollution can be caused by natural causes -volcanic eruption fills air with dust and ash. What Causes Pollution?. - PowerPoint PPT PresentationTRANSCRIPT
CHAPTER 19.3Pollution and Recycling
What Causes Pollution?
Pollution is the contamination of air, water, or soil
What Causes Pollution?Pollution can be caused by natural causes
-volcanic eruption
fills air with dust and ash
What Causes Pollution?Most pollution is caused by human activities -reactions create products that if not used properly, add to the pollution problem
Air PollutionAir pollution comes in many forms -individual molecules to clumps of dust and matter , called particulates
Air PollutionBurning of fossil fuels produces energy, along with carbon dioxide and water vapor
-escape into air
as invisible gases
Air PollutionCarbon dioxide is found naturally in the atmosphere -greenhouse gas that helps keep Earth’s temperature balanced
-without it, Earth’s temperature would be about 33 degrees lower -humans put billions of tons into the air each year
Air Pollution-burning of fossil fuels also releases sulfur dioxide and nitrogen dioxide into the air -react with other atmospheric gases to form acid rain -makes streams and lakes acidic -can harm or kill aquatic life-can acidify soil-corrode metals and stone buildings
Air Pollution-nitrogen oxide can react with sunlight to form photochemical smog -brown haze that stings eyes and cause severe headaches and breathing difficulties
-most common in sunny, densely
populated cities
Water Pollution-most water pollution can be traced to industrial waste, agricultural fertilizers, and everyday human activities -fertilizers get washed away by rain into lakes and rivers-contain nitrate ions, which encourage growth of bacteria and algae
Water Pollution-feeding on the nitrates, bacteria and algae grow so fast that they use up most of the oxygen in the water-algal bloom -kills fish and other aquatic wildlife-process is called eutrophication
Water Pollution-pesticides can be washed into lakes and rivers by rain -eaten by fish and other aquatic animals
-passed along food chain
Land Pollution-a common type of land pollution occurs when hazardous chemicals soak into the soil.
Reducing Pollution-government regulation discourages pollution of air, water, and land-use of alternative energy and conserving energy can reduce pollution
Reducing Pollution-recycling allows materials to be used again rather than being thrown away -saves landfill space and conserves scarce resources