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Environment• All the physical and social conditions
surrounding a person.• EPA (Environmental Protection Agency) is a
government agency in charge of protecting our water.• Less than 1% of the earth’s water is in a form that
humans can use. • Water supply limited, but also unevenly distributed.• An estimated 500 million people around the world
have trouble getting the water they need to live.• Water disputes could lead to major conflicts • Water
Homeostasis
• Homeostasis: steady state of conditions in the environment; Balance of Nature
• Many human activities alter homeostasis– Clearing forests, pollution, farming, settlement,
harvesting resources• Demand for land in its varying uses increases
as the human population increases.• As population increases….
Water Pollution• Pollution: accumulation of harmful wastes or other
harmful substances into the environment• Biodegradable Wastes: Waste that can be broken
down by microorganisms.– Only causes pollution if wastes are released more rapidly
than they can be decomposed. (ex: raw sewage into a river)• Non – partially biodegradable wastes: include motor
oil, pesticides, solvents, mercury, arsenic and lead• These accumulate in the environment and
contaminate organisms.
1. Water Pollutants - Runoff
• Water Runoff: is water that runs off the land into a body of water.– Snow melting, rain, watering lawns, crops. Some
absorbed, but some runs along the surface until it reaches another water outlet.
– The water that is absorbed goes into an unground stream known as groundwater.
– As it runs it picks up Pollutants.
2. Water Pollutants - Sediment• Runoff can carry soil and other sediments into
the water supply. This can clog lakes and rivers. Sediments destroy feeding grounds of fish and other animals. Also large scale construction can cause erosion which leads to sediments.
Eutrophication:• Runoff can contain fertilizers which can cause
algae to grow too rapidly, using up all the O2 in the water which causes eutrophication.
• Eutrophication: the process of excessive algae growth followed by decay and lack of O2.
2. Water Pollutants - Wastewater• Wastes from homes, communities, farms and
businesses.• Sewage: Waste material from toilets and drains.– In the past some communities have drained sewage
directly into sources such as rivers and oceans.– Diseases such as hepatitis A, can be easily spread in
this manner. – In 1972 the Clean Water Act passed, which in part
require treatment of raw sewage before releasing it.
Wastewater continued…
• Industrial pollution: comes from mining and manufacturing activities. These are extremely toxic and non-biodegradable.– Includes: dyes, acids, solvents, heavy metals,
(mercury, lead, cadmium)– Used to be common to release these into the
ground or surface waters.
Other Sources• Oil spills: from oil tankers and offshore drilling. Also from oil
poured down drains or onto the ground. • Household cleaners• Chlorine is toxic to all forms of life and can react with other
substances to create carcinogens• Dioxins: Group of chemicals used in insecticides. Paper mills
(bleaching paper), forest fires, volcanic eruptions. Found in fish then passed to people.
ConservationConservation: Avoiding waste through careful management of natural resources.• Repair leaky faucets• Wait until you have a full load to do laundry• Low flow showerheads• Avoid overwatering yard• Decrease use of household cleaners (less
hazardous)• Discard hazardous waste properly with local
authorities
Recycling Facts1. The average person generates over 4 pounds of trash every day and about 1.5 tons of solid waste per year.2. Americans make more than 200 million tons of garbage each year, enough to fill Busch Stadium from top to bottom twice a day. 3. Over 75% of waste is recyclable, but we only recycle about 30% of it.4. We generate 21.5 million tons of food waste each year. If we composted that food, it would reduce the same amount of greenhouse gas as taking 2 million cars off the road.5. Recycling one aluminum can saves enough energy to listen to a full album on your iPod. Recycling 100 cans could light your bedroom for two whole weeks.6. Recycling aluminum cans saves 95% of the energy used to make alum cans from new material.7. Americans throw away 25,000,000 plastic bottles every hour.8. Over 87% of Americans have access to curbside or drop-off paper recycling programs.9. In 2009, Americans threw away almost 9 million tons of glass. That could fill enough tractor trailers to stretch from NYC to LA (and back!).10. In 2010, paper recycling had increased over 89% since 1990.11. If every American recycled just one-tenth of their newspapers, we could save about 25 million trees each year.Dosomething.org
Three R’s
• Reduce: prerecycling. Reducing waste before it is generated. (cloth napkins)
• Reuse: Sell it, reuse it, donate it, repair it• Recycle: the processing of waste materials so
that they can be used again.
• Water Pollution