Environmental Science

• Environmental science is defined as the interaction of humans with the environment.

• The environment includes all conditions that surround living organisms:

– Climate

– Air and water quality

– Soil and landforms

– Presence of other living organisms

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Environmental Science Cont’d

• Environmental science and the issues that it studies are complex and interdisciplinary.

– Includes concepts and ideas from multiple fields of study.

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Image taken from Principles of

Environmental Science,

Cunningham, 2005.

What is the Goal of Environmental Science?

• A major goal of environmental science is to understand and solve environmental problems.

• To accomplish this goal, environmental scientists study two main types of interactions between humans and their environment:

• How our actions alter our environment.

The use of natural resources like water, coal, and oil.

• Natural resources are any natural materials that are used by humans, such as, water, petroleum, minerals, forests, and animals.

• Natural resources are classified as either a renewable resources or a nonrenewable resource.

• Renewable resources can be replaced relatively quickly by natural process.

• Nonrenewable resources form at a much slower rate than they are consumed.

How is Environmental science different than ecology?

• Environmental science is an interdisciplinary science, which means that it involves many fields of study.

• Important to the foundation of environmental science is ecology.

• Ecology is the study of interactions of living organisms with one another and with their environment.

Basic History of Humans and the Environment

• Hunter-Gatherers (10,000 B.C.)

– Obtain food by collecting plants and hunting wild animals.

– No organized agriculture or animal raising.

– Effects on the environment were limited.

• Hunting of some animal species.

• Picked up and spread plants/seeds to new areas.

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Basic History of Humans and the Environment

• Agricultural Revolution (6000-7000 B.C.)

– Humans first developed the process of breeding, growing, and harvesting plants for food as well as animal domestication.

– Effects on the environment:

• Human population grew more quickly

• Natural habitats (grasslands, forests) replaced by farmland and villages.

• New breeds of animals and plants were created.

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Basic History of Humans and the Environment

• Industrial Revolution (1800s)

– Shift in the source of energy to fossil fuels

– Effects on the environment:

• More efficient farming

• Faster human population growth

• Increased burning of fossil fuels.

• Introduced synthetic plastics, fertilizers, pesticides.

• Higher amounts of pollution.

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Spaceship Earth

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• The Earth is a closed system.

The only thing that enters or leaves the Earth in

large quantities is heat.

Resources are limited, but the population

continues to increase.

Wastes do not go away.

Major Environmental Problems

• Resource Depletion

– Resources can be renewable (water) or nonrenewable (petroleum).

– The supply of nonrenewable resources like fossil fuels and minerals will eventually run out.

– The supply of renewable resources is often used so quickly that it cannot be replenished.

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Major Environmental Problems• Pollution

– Undesired change in air, water, or soil that affects the health of living things.

– Biodegradable pollution will break down naturally over time.

– Nondegradable pollution does not break down.

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Major Environmental Problems

• Loss of Biodiversity

– Biodiversity is the number of different species present in an ecosystem.

– Extinction, or the complete loss of a species, is a natural event that can be accelerated by human actions.

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The Tasmanian tiger is the only known mammal to becomeextinct in the past 200 years on the island of Tasmania.

During the same period of time, on nearby Australia,23 birds, 4 amphibians, and 27 mammal species have become extinct.

Environmental Ethics

• Environmental ethics is the discipline that studies the moral relationship of human beings to the environment.

– What is the value of the environment?

– What moral responsibility do we have?

– Which needs should be given the highest priority in our decision making?

• Different types of ethics have emerged in human culture in modern history.

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Types of Environmental Ethics

• There are five main historical stages of environmental ethics.

– Anthropocentric

– Pragmatic Resource Conservation

– Moral and Aesthetic Nature Preservation

– Modern Environmentalism

– Global Environmental Citizenship

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Anthropocentrism

• Anthropocentrism literally means “human-centered”.

– This set of ethics protects and promotes of human interests or well-being at the expense of all other factors.

– Often places an emphasis on short-term benefits while disregarding long-term consequences.

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Pragmatic Resource Conservation• Advocated by President

Theodore Roosevelt.

• Conservationists believe the environment should be used in a planned way to benefit everyone.

• The correct policy will create the greatest good for the greatest number, for the longest time.

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Moral and Aesthetic Nature Preservation

• Advocated by John Muir, first president of the Sierra Club.

• Preservationists believe that nature deserves to exist for its own sake regardless of degree of usefulness to humans.

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Ecological Principles

"The college idealists who fill the

ranks of the environmental

movement seem willing to do

absolutely anything to save the

biosphere, except take science

courses and learn something

about it."

— P.J. O'Rourke

Ecological Principles

• are basic assumptions ( or beliefs) about

ecosystems and how they function and are

informed by the ecological concepts

• build on ecological concepts to draw key

conclusions that can guide human applications

aimed at conserving biodiversity

Principle #1

Protection of Species and species’

subdivisions will conserve genetic

diversity

• continued existence of species and their

adaptation to changing conditions

•To retain a variety of individuals and

species permits the adaptability needed

to sustain ecosystem productivity in

changing environments

Principle #1

Protection of Species and species’

subdivisions will conserve genetic

diversity

• sustaining ecosystem productivity can

also beget further diversity ( and future

adaptability)

Principle #2

Maintaining habitat is fundamental

to conserving species

• a species habitat is the ecosystem

conditions that support its life

requirements

• can be considered at a range of spatial

and temporal scales

Principle #3Large areas usually contain more

species than smaller areas with

similar habitat

• theory of island biogeography

• “ a system of areas conserved for

biodiversity that includes large areas can

effectively support more viable

populations”

Principle #4All things are connected but the

nature and strength of those

connections vary

• ecological relationships

• ecological niche

Principle #5Disturbances shape the

characteristic of populations,

communities and ecosystems

• the type, intensity, frequency and

duration of disturbances shape the

characteristics of populations,

communities and ecosystems including

their size, shape and spatial relationships

Principle #6Climate influences terrestrial and

aquatic ecosystems

• climate has a dominant effect on

biodiversity as it influences meteorological

variables like temperature, precipitation,

and wind with consequences for many

ecological and physical processes

aggregation of individuals ( ecosystem structure)

ecological succession ( ecosystem dynamics)

assimilative capacity ( changes in physical environment)

biological concentration (biomagnification/bioaccumulation)( changes in physical environment)

carrying capacity (changes in physical environment)

competitive exclusion principle (community ecology)

Precautionary Principle ( Precautionary Strategy) Climate Change ( “Act now to reduce the risks”)

Ecological Principles

Limiting Factor Principle

Go Green

Live

Green

Think

Green