Chapter 1, Section 1

CHAPTER 1, SECTION 1

Understanding our

Environment

ENVIRONMENT:

Includes the natural world as well as things produced by humans. It is a complex web of

relationships that connects us with the

world we live in.

ENVIRONMENTAL SCIENCE…WHAT IS IT?

The study of how humans interact with the environment

Ecology is the study of how living things interact with each other and with their nonliving environment, so….Environmental Science = Ecology + Human Interaction

ENVIRONMENTAL SCIENTISTS STUDY 2 MAIN TYPES OF INTERACTIONS BETWEEN

HUMANS AND THEIR ENVIRONMENT.

Area 1:How we use natural resources such as water and plants

Area 2:How our actions alter our environment

ENVIRONMENTAL SCIENCE INVOLVES MANY FIELDS OF STUDY THAT INCLUDE:

Other Sciences:BiologyEarth SciencePhysics ChemistrySocial Sciences:

Geography, Anthropology, and Sociology

*Refer to Table 1, pg. 7 to supplement your notes

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•Environmental Change is not a new issue, wherever humans have hunted, grown food, or settled, they have changed the environment

•There are three major environmental changes made by humans over the years which we will discuss next

HUNTER-GATHERERS

For most of human history, people were hunter gatherers (people who obtain food by collecting plants and hunting wild animals)

HUNTER-GATHERERS CHANGED THEIR ENVIRONMENT IN

MANY WAYS INCLUDING:

Set fires to burn the prairies and prevent the growth of trees so the prairies would remain open grasslands where they could hunt bison

Helped spread plants to areas where plants did not originally grow because many of the early hunter-gatherers migrated from place to place

Over hunted many large mammal species possibly leading to extinction

EVENTUALLY HUNTER GATHERERS BEGAN TO COLLECT THE SEEDS OF THE PLANTS THEY GATHERED AND TO DOMESTICATE SOME OF THE ANIMALS IN THEIR ENVIRONMENT WHICH LED TO WHAT IS CALLED THE Agricultural Revolution

AGRICU

LTURAL

REVOLU

TION

Agriculture is the practice of growing, breeding, and caring for plants and animals that are used for food, clothing, housing, transportation, and other purposes.

The practice of agriculture started in many different parts

of the world over 10,000 years ago.

This change had such a dramatic impact on human societies and

their environment that is often called

the agricultural revolution

THE AGRICULTURAL REVOLUTION CHANGED THE ENVIRONMENT OF THAT TIME IN MANY DIFFERENT WAYS INCLUDING: Allowed human populations to grow rapidly (an

area of land can support up to 500 times as many people by farming as it can by hunting and gathering)

The food we eat (the plants we grow and eat descended from wild plants)

As grasslands, forests, and wetlands were replaced with farmland, habitats were destroyed

The replacement of forest with farmland on a large scale can lead to soil loss, floods, and water shortages and was the case of this time period

INDUSTRIAL REVOLUTION In the 1700s, there was a shift from

using man or animal powered machinery to using machines powered by fossil fuels such as steam engines.

This shift changed society and greatly increased the efficiency of agriculture, industry, and transportation.

THE INDUSTRIAL REVOLUTION BROUGHT MANY CHANGES

Positive Changes Negative Changes

Invention of the light bulb

Agricultural productivity increased

Sanitation, nutrition, and medical care improved

As the human population grew, many environmental problems such as pollution and habitat loss became more common

The use of plastics, pesticides, and fertilizers began being used which present environmental problems as well

Much of environm

ental science is concerned with

the problems associated with the Industrial

Revolution.

TODAY, INFORMATION IS WIDELY AND QUICKLY

DISTRIBUTED THROUGH TV, RADIO, AND INTERNET. MANY PEOPLE THINK THAT

THE “INFORMATION REVOLUTION” IS A

DISTINCT PHASE OF HUMAN HISTORY WHILE

OTHERS ARGUE THAT THE INFORMATION REVOLUTION

IS PART OF THE INDUSTRIAL REVOLUTION.

Wha

t is

your

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SPACESHIP EARTH The concept of Earth

being compared to a spaceship traveling through space that cannot dispose of waste or take on new supplies (is a “closed system”)

What problems do you think this causes for our Earth?

Our Main Environmental Problems:

Resource Depletion

PollutionLoss of Biodiversity

RESOURCE DEPLETION Resources are said to be depleted when a large fraction of a resource has been used up

Any natural material that is used by humans is called a Natural Resource

NATURAL RESOURCES

Renewable Resources Nonrenewable Resources

A resource that can be replaced relatively quickly by natural processes

Examples: Air Fresh Water Soil Trees Crops Sun (energy)

A resource that forms at a much slower rate than the rate that it is consumed

Examples: Fossil Fuels (oil, coal,

natural gas) Metals such as

Aluminum, Iron, and Copper

Salt, Sand, and Clay

POLLUTION Is an undesired change in air, water, or

soil that adversely affects the health, survival, or activities or humans or other organisms

Much of the pollution that troubles us today is produced by human activities

THERE ARE 2 MAIN TYPES OF POLLUTANTS:

Biodegradable Pollutants Nondegradable Pollutants

Can be broken down by natural processes

Include materials such as human sewage or a stack of newspapers

Cannot be broken down by natural processes

Include materials such as mercury, lead, and some types of plastics

Can build up to dangerous levels in the environment

LOSS OF BIODIVERSITY Biodiversity: the number and variety

of species that live in an area. Earth has been home to hundreds of

millions of species, yet only a fraction of those species are still alive today because of extinction.

Organisms that share the world with us can be considered natural resources because we depend on them for food, the oxygen we breathe, and for many other things.