Transcript Science and the Environment

Science and the Environment
Understanding Our Environment
Section Objectives
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List the five major fields of study associated with
Environmental Science
Describe the major effects of hunter-gatherers,
the Agricultural Revolution, and the Industrial
Revolution.
Distinguish between renewable and
nonrenewable resources
Classify environmental problems into three major
categories
Environmental Science
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The study of air, water, and land
surrounding an organism or a community
Included:
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Impact of humans
Small areas
Earth’s biosphere
Interdisciplinary Science
Environmental Science
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To understand and
solve environmental
problems
Studies human use of
resources
Studies impact of
human use
Environment Through Time
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Hunter-gatherers- Obtained
food by collecting plants,
hunting and/or scavenging
animals
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Burned grasslands
Killed buffalo in large
numbers
Over hunting caused
extinctions of:
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Giant sloth
Giant bison
Mastadons
Cave bears
Saber-toothed cats
Hunted to Extinction
Hunter-Gatherers
Environment Through Time
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The Agricultural Revolution- Growing and
raising food for human consumption
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Started over 10,000 years ago
Human populations increased dramatically
Concentrations of people affected environment
Domesticated plants from wild plants
Slash and burn
Causes soil loss, floods, and water shortage
Poor farming practice rendered = useless land
The Agricultural Revolution
Environment Through Time
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Industrial Revolution- Shift to using fossil fuels
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Efficiency of agriculture, industry, and transportation
Mass production = lower cost
Machinery reduced land and human labor needed
Human populations grew at an extraordinary rate
Urban areas grew = more pollution and habitat loss
Improvements:
 Inventions- Light bulb, plastics, pesticides, fertilizers
 Sanitation
 Nutrition
 Medical care
The Industrial Revolution
Local
Spaceship Earth
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Earth is a closed system
Nothing enters but
energy from sun
Nothing leaves except for
heat
Some resources are
limited
Waste produced faster
than disposal
Today’s Problems
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Local problems- Landfills
Regional problems- River water shortage
Global problems- Ozone depletion &
global warming
Resource Depletion
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Resource depletion- Large
fractions used up
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Natural resources Renewable- Can be
replaced within a human
lifetime
 Nonrenewable- Can’t be
replaced within a human
lifetime
Pollution
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Undesirable change in environment caused
by introducing harmful substances,
excessive waste, heat, noise or radiation
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Biodegradable-Can be broken down by
natural processes
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Build up faster than broken down
Nondegradable-Can’t be broken down by
natural processes
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Build up at dangerous levels
Pollution
Loss of Biodiversity
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Biodiversity- Variety of organisms in a
given area
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Genetic variety in a population
Variety of species in community
Variety of communities in ecosystem
Extinction- none left
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Preservation important