Water Pollution

Types of Water Pollution• Effect of sewage on dissolved oxygen and

biological oxygen demand

Types of Water Pollution• Eutrophication: An Enrichment Problem

Oligotrophic lake

Types of Water Pollution

• Eutrophication: An Enrichment Problem

Eutrophic lake

Types of Water Pollution• Sediment Pollution

Low sediment load

Types of Water Pollution• Sediment Pollution

High sediment load

Types of Water Pollution

• Inorganic Plant and Algal Nutrients

• The Dead Zone in the Gulf of Mexico

Water Quality Today• Municipal Water Pollution

Water Quality TodayGroundwater Pollution

Improving Water Quality

• Purification of Drinking Water

• General process:

Collected from reservoir or ground water.

Improving Water Quality

• Purification of Drinking Water

• General process:

Water treated

Improving Water Quality

• Purification of Drinking Water

• General process:

Distributed to customers

Wastewater collected as sewage

Improving Water Quality• Purification of Drinking Water

• General process:

Sewage treated

Improving Water Quality

• Municipal Sewage Treatment

Primary and Secondary Sewage Treatment

Improving Water Quality• Individual Septic Systems

Septic tank

Improving Water Quality

• Individual Septic Systems

Drain field/Leach Fields

Laws Controlling Water Pollution

• Case-in-Point: Water Pollution in the Great Lakes

What is a Pesticide?• First-Generation Pesticides

• Inorganic compounds (e.g., lead, mercury)

• Botanicals (e.g., nicotine, pyrethrin)

Benefits and Problems with Pesticides

• Benefit: Disease Control

Location of malaria

Benefits and Problems with Pesticides

• Problem: Evolution of Genetic Resistance

# of species exhibiting genetic resistance to pesticides

Benefits and Problems with Pesticides• Problem: Evolution of Genetic Resistance

• Creates a pesticide treadmill

Pesticide application

Kills most pests

Resistant survive

Numbers increase

New population genetically resistant

EVEN MORE

INCREASE

Benefits and Problems with Pesticides

• Problem: Imbalances in the Ecosystem

• Creation of New Pests

Benefits and Problems with Pesticides

• Problem: Persistence, Bioaccumulation, and Biological Magnification

Biomagnification of DDT

Benefits and Problems with Pesticides

• Problem: Mobility in the Environment

Risks of Pesticides to Human Health

• Short-term Effects of Pesticides

• Handling of food with pesticide residue

Alternatives to Pesticides

• Integrated Pest Management

Alternatives to Pesticides

• Integrated Pest Management

Rice Production in Indonesia

IPM introduced

World Food Problems

• Common diseases due to malnourishment:

• Kwashiorkor

kwa·shi·or·kor (kwä'shē-ôr'kôr')    Severe protein malnutrition, especially in children after weaning, marked by lethargy, growth retardation, anemia, edema, potbelly, skin depigmentation, and hair loss or change in hair color.

Common diseases due to malnourishment:

• Ma·ras·mus (mə-răz'məs)

• A progressive wasting of the body, occurring chiefly in young children and associated with insufficient intake or malabsorption of food.

World Food Problems• Maintaining Grain Stockpiles

• World grain carryover stocks

U.N. estimates that carryover stocks should not fall below 70 days.

The Principal Types of Agriculture

• Industrialized agriculture

Challenges of Producing More Crops and Livestock

• Increasing Crop Yields

US wheat yields

Challenges of Producing More Crops and Livestock

• Genetic Engineering

Solutions to Agricultural Problems• Sustainable Agriculture

Fisheries of the World

•Overharvesting is the most serious problem

Hazardous and Solid Waste

• Types of Solid Waste Paper andPaperboard

Yard Waste

Food Waste

Plastics

Metals

Rubber, leather, &textiles

Glass

Wood

Other

Solid Waste

• Disposal of Solid Waste- Too many landfills!

SanitaryLandfills

Recycling

Incineration

Sanitary Landfills

Solid Waste

• The Special Problem of Tires

• Made from materials that cannot be recycled

• Can be incinerated

Solid Waste

• Disposal of Solid Wastes

• Incineration

CO2 emissions per kwatt-hour of electricity production

Solid Waste• Mass burn incinerator

Waste Prevention

• Recycling, Composting, Reusing

Solid waste produced by average family of four in one year in US

Waste Prevention• Integrated Waste Management

Hazardous Waste

• Case-in-Point: Hanford Nuclear Reservation

Drums of low-level nuclear waste

Hazardous Waste• Hazardous waste landfill