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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?