Chapter 1: Key Themes in Environmental Sciences

1.1 Major Themes of Environmental Science

1. Our population has more than doubled in the last 40 years 6.8 billion people alive today

2. Continuing on this trend would lead to 9.4 billion by 2050

3. How many people can the Earth sustain? Depends on science and value Also question of people and nature

1.2 Human Population Growth

Human Population density is over 6.3 billion It has doubled over the past 40 years

Due to science advancementsReduced infant mortality

John Eli Miller Family

Example of family population explosion

1.2 Human Population Growth

Miller family emphasizes a major factor in modern population explosionModern technologyModern medicine Supply of food, clothing and shelterAll decrease the death rate and increase net

growth rate

Our Rapid Population Growth

Human population growth is the underlying issue of the environment.Damage is directly or indirectly due to pop inc

Famine and Food CrisisFamine occurs when human pop exceeds its

environmental resources

Sahel region of Africa in 1970s½ million people starved to death Millions affected by malnutrition

Emerging global food crisisDue to rise in fuel cost = higher food cost

Famine and Food Crisis

Food Crisis

1.3 Sustainability and Carrying Capacity

What is the maximum number of people the Earth can sustain?Much of this book will help answer that ?

Currently we are using resources unsustainably.Faster that they can be replenished.

Sustainability: The Environmental Objective

Is Earth very survival really in danger?Earth will go on w/o usQuality of human enviro at risk

SustainabilitySustainability refers to resources and their

environment.

Sustainable resource harvestSame quantity of that resource can be harvested

each year for an unlimited amount of time.

Sustainable ecosystemAn ecosystem from which we are harvesting a

resource that is still able to maintain its essential functions/properties.

SustainabilityTwo points to understanding sustainability

Sustainability means for an unspecified long period of time.

Sustainable growth is an oxymoron.

Sustainable Global Economy

Population of humans living in harmony w/ natural support systems.

An energy policy that does not pollute, cause climate change or present unacceptable risk.

A plan for renewable resources that will not deplete the resources or damage ecosystems.

Sustainable Global Economy

A plan for nonrenewable resources that does not damage region or global environ.And provides a share for future generations

A social, legal, and political system that is dedicated to sustainability.

Sustainable Global Economy

To achieve we mustDevelop an effective population-control strategy.Completely restructure our energy programs. Institute economic planning that will encourage

pop control and wise use of resources. Implement social, legal, political and eductional

change.

Moving Toward Sustainability

The new paradigmEvolutionary rather than revolutionary. Inclusive, not exclusive.Proactive, not reactive.Attracting, not attacking.Assisting the disadvantage, not taking advantage.

Carrying Capacity of the Earth

Defined as the maximum number of ind of a species that can

be sustained by an environmentw/o decreasing the capacity of the environ to

sustain that same amount in the future

1.4 A Global PerspectiveThe actions of many groups of people at many

locations affects the environment of the entire world.

Gaia hypothesis James Lovelock and Lynn MargulisLife affects the environment at a global level

1.5 An Urban WorldWe are

becoming an urban species

In developed countries75% live in

urban area

Developing countries40%

1.5 An Urban World

Megacity Urban area

with at least 10 million inhabitants

By 2015 the world will have 36 megacities

23 of them in Asia

1.5 An Urban world Scientist James Lovelock

One of the creators fo the Gaia Hypothesis

Has said that in order to survive to preserve our biological life support system (Earth)

We need to live in domed cities isolated from nature

1.6 People and NatureWe depend on nature directly for

WoodWater Air

And indirectly for “public services functions”E.g. soil formation

Soil Fertility and Structure

People and NaturePeople and animals

alter and change their environment.

Dichotomy of 20th century is giving way.

New unity Sustainable

environment and economy compatible.

1.7 Science and Values

We must choose what we want the environment to be

Value judgment regarding the world’s human population problemChoice between desire to have large family and

the need to limit the human population.

The more high tech and powerful our civilization, the more knowledge is required.

Fishing for Salmon

Precautionary Principle1992 - Rio Earth Summit on Sustainable

Development

Defined PP – when there is a great threat of serious environ damage we should not wait for scientific proof before taking precautionary steps to prevent potential harm.

Precautionary PrinciplePP is a proactive,

rather than a reactive, tool.

Adopted by the city of SF and the European Union

Placing a Value on the Environment

The value of the environment based on 8 justifications Utilitarian Ecological Aesthetic Recreational

Inspirational Creative Moral Cultural

Placing a Value on the Environment

Utilitarian- the environment has value because it benefits individuals economically or is necessary for human survival.

Ecological- ecosystem is necessary for survival of some species of interest or that the system itself provides benefit.

Placing a Value on the Environment

Aesthetic- has to do with our appreciation of the beauty of nature.Recreational- viewing organisms in a natural

setting. Inspirational- to benefit the inner selfCreative- aid to human creativity

Placing a Value on the Environment

Moral- the belief that various aspects of the environment have the right to exist and it is our obligation to allow them to continue.

Critical Thinking Issue How can we preserve the

world’s coral reef? 10% Have been destroyed 30% are threatened

Fishing with explosives Harvest of coral for

precious stone market Introduced predators Disease related to

climate change Acidification of the

ocean Water quality They are extremely slow

growing

Questions How does the coral

problem relate to the key themes in this book?

What utilitarian, ecological, moral and aesthetic values do they have?

What can you do to help preserve the coral reefs?