Important reminders:

Presentation on Honors course 3 & 4 October @ 13:15 in Science Centre, Westville Campus

!!!!!!! Hons. Applications close 31 October for admission in 2008!!!!!

Download Biol347 PowerPoint presentations:

http://marinesci.ukzn.ac.za/documents/

and choose the BIOL347 folder

REMEMBER: Each week’s presentations will only be available after the Tuesday lecture.

Presentation only provide the framework, please do some extra reading on each subject – you are expected to do 68 hours of self-study during the

course of the semester, i.e. about 5 hours per week

The Environment and People

Overview of Environmental science

Human Population growth

The Environment Live on Earth

The Biosphere: Populations, Communities, Ecosystems and

Biogeochemical cycles

The distribution of Live on Earth

The dynamic earth and Natural Hazards

Resource use and management

People and natural resources

Fundamentals of energy, fossil fuels, nuclear energy

Renewable and alternative energy sources

Water resources

Conserving Biological Resources

Land Resources and management

Food and Soil Resources

Dealing with Environmental Degradation

Principles of Pollution control, Toxicology and Risk

Water Pollution

Air Pollution: Local and Regional

Air Pollution: Destruction of the Ozone layer and global climate

change

Municipal Solid Waste and Hazardous WasteSocial Solutions to

Environmental Concerns

Environmental Economics

Historical and Cultural Aspects of Environmental Concerns

Principles of Pollution Control

Pollution and waste are symptoms, not causes, of the environmental crisis.

Paul Hawken

Pictures © 2006 Jones and Bartlett Publishers

Chapter objectives

• What is meant by “pollution”

• How pollution is produced

• How pollution is controlled

What is pollution?

Pollution = society’s excess output into the environment

Something produced in amounts high enough to be harmful to us, other life, or valuable objects

Pollution has many faces

Pollution as matter cycling and energy flow

The environment ultimately consists of matter cycles and energy flows.

Pollution represents local concentrations in the matter cycle or energy flows

e.g. Heat pollution is a form of air and water pollution

Pollution has many faces

Pollution as an accelerated natural process

Not only man-made, e.g. Volcanoes release gasses that is harmful to life, affect global climate and cause acid rain.

People cause pollution at a greater rate than nature, because:•High quantities of waste produced•Quality of waste accelerates pollution because of lots of new substances e.g. dye

Pollution has many faces

Pollution as a stepwise process

High volumes of waste produced as by products for other products/ processes

“Everything must go somewhere” as either energy flowing or matter cycling

As a result, waste often end up in water, air or land.

Life Cycle Analysis (LCA) / Cradle to grave analysis can pinpoint steps in processes that can either be eliminated or made more efficient

Therefore: “Cradle to grave” pollution = the many ways a product can pollute in its lifetime

Pictures © 2006 Jones and Bartlett Publishers

Pollution has many faces

Pollution as a stepwise process

Pictures © 2006 Jones and Bartlett Publishers

Pollution has many faces

Pollution = population x consumption

The amount of pollution depends on:

(1)The number of people(2)The amount of waste produced per person (determined by

consumption)

Therefore:

Pollution = population x consumption

OR

Pollution = population x consumption

OR

Pollution = population x consumption

History of pollution

Pollution exists from the beginning of time!!!

• Ancient volcanoes helped form the atmosphere

• Later on gasses from erupting volcanoes caused mass

extinctions

• Animals pollute rivers with urine and feces

• Bird droppings can contaminate areas surrounding nests

• Early civilizations discarded their waste (evidence in caves)

• Egyptians and Greeks had polluted drinking water Today, the scale of pollution is much greater due to:

• Large human population

• Fossil fuel-driven technologies

Controlling pollution

No water is pure in nature:

• Before people existed, water contained gasses and other

substances

• Highly polluted water only contain 1 % toxins and other

pollutants

• Raw sewage entering treatment facilities contained at least

99.9 % water. The problem: sewage and toxicant

molecules are much larger than water molecules

Zero pollution is an unrealistic goal:

• Modern society cannot exist without producing pollutants

• Total purity is economically impossible – the cost of

removing all pollutants increases exponentially after a

given point

• Total purity is unnecessary – the benefits of pollutant

removal decrease exponentially after a given point

• Not even nature is totally pure

Controlling pollution

How much to control?

Pictures © 2006 Jones and Bartlett Publishers

Controlling pollution

What to control?

Pictures © 2006 Jones and Bartlett Publishers

Low cost High cost

Controlling pollution

Pollution control vs. remediation vs. restoration

Remediation counteracts some of the effects of pollution after it has been released into the environment, e.g. treat lakes contaminated with acid rain with lime. Very expensive

Restoration seeks to reinstate the environment to its former condition. Extremely expensive

Pollution control aims to remove the pollutant and dispose of it in a landfill or incinerator, e.g. cleaning up toxic fly ash from electricity generating plants. Very expensive.

Controlling pollution

Implementing pollution control

There are three basic ways prevent people from polluting:

Persuasion: Ask people to change polluting behavior. Should be accompanied by education. Very cheap, but not too effective.

Regulation: Pass laws requiring less pollution. Most useful when polluters are few in numbers and pollution can be easily monitored, e.g. hazardous waste of large factories.

Incentives: Reward behavior that reduces pollution, e.g. tax incentives and subsidies for renewable energy use. Much lower cost than regulation. Examples: (1) deposits paid when potential waste is purchased and (2) pay as you throw schemes, where the polluter has to pay for discarding waste

Controlling pollution

Implementing pollution control

There are three basic ways prevent people from polluting:

Persuasion: Ask people to change polluting behavior. Should be accompanied by education. Very cheap, but not too effective.

Regulation: Pass laws requiring less pollution. Most useful when polluters are few in numbers and pollution can be easily monitored, e.g. hazardous waste of large factories.

Incentives: Reward behavior that reduces pollution, e.g. tax incentives and subsidies for renewable energy use. Much lower cost than regulation. Examples: (1) deposits paid when potential waste is purchased and (2) pay as you throw schemes, where the polluter has to pay for discarding waste