Transcript UNIT 3: LIVING AND LAND RESOURCES

UNIT 3:
CONSERVATION OF
NATURAL RESOURCES
CHAPTERS 3, 4 and 5
(ENVIRONMENTAL SCIENCE)
WHAT IS
ENVIRONMENTAL SCIENCE?
• Def: The study of how
humans impact their
environment
– What book is this?
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Once-ler
Truffula Trees
Barbaloots
Swomee-Swans
Humming Fish
Thneeds
Lorax
• Environmental Issues:
– Class List
• Key People and Events:
– John Muir – Sierra Club
– Teddy Roosevelt –
National Refuges/Parks
– Rachel Carson – Silent
Spring
ENVIRONMENTAL
DECISION-MAKING
• TYPES OF ISSUES
– RESOURCE USE
• RENEWABLE VS NONRENEWABLE RESOURCES
– POPULATION GROWTH
• FASTER THAN EVER  EXPONENTIAL GROWTH
• DOUBLE PROBLEM: MORE PEOPLE  MORE
RESOURCES NEEDED; MORE PEOPLE LESS
AVAILABLE LAND TO GET THESE RESOURCES
• TECHNOLOGY HAS TO MAKE UP THE DIFFERENCE
– POLLUTION
ENVIRONMENTAL
DECISION-MAKING
• WHAT TO CONSIDER WHEN MAKING AN
ENVIRONMENTAL DECISION?
– IDENTIFY ISSUE
– CONSIDER VALUES – ideas that people think are important;
different for different groups of people
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Economic – money
Environmental – environment
Convenience – how will it make life easier
Recreational – fun
Health – is it safe
Scientific/Educational – what can we learn
Religious/Cultural – family or society values; traditions
Aesthetic – pleasing to the senses
Political – how the public will react (public opinion)
– ANALYZE CONSEQUENCES
• PROS AND CONS (COSTS AND BENEFITS)
• IMMEDIATE, SHORT-TERM AND LONG-TERM
ENVIRONMENTAL
DECISION-MAKING
• YELLOWSTONE WOLF REINTRODUCTION
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For background article: click here
1995 – 14 wolves reintroduced
Why did they do it?
Why were some people opposed?
What do you think?
Would your thinking be different if it was around
here?
• Mountain Lion Article
• Mountain Lion Video
LIVING RESOURCES:
• SUSTAINABLE YIELD – the amount of a
renewable resource that can be used without
reducing the supply for the future
– Managing without overusing
• FORESTRY – managing the forests to get the
resources from trees, while keeping the same
amount of forests year after year
– Products from Trees (why are forests important?)
– Logging Methods: (know pros and cons)
• Clear cut – taking all trees from an area
• Selective Cut – only take certain species or size of tree
LIVING RESOURCES:
• FISHING INDUSTRY
– Products from the sea
– Fishery – areas of the ocean with large populations
of valuable organisms
• 70% have been overfished
• Ways to help maintain sustainable yield:
– Laws and Limits
– Use Better Techniques
» Dolphins and tuna example
– Aquaculture – fish farming
» Raise the fish in artificial environments and harvest
» Can be used for freshwater resources as well
– Find New Resources
LAND USE
• Development
– Construction of roads, buildings, dams etc. for human use
• Mining
– The removal of nonrenewable resources
– Shaft Mining – digging deep into the ground for resources
• Coal
– Strip mining – scraping the surface of the Earth for resources
• Minerals, iron, copper
– Dangers:
• Cave-ins
• Fires
• Acid-mine drainage
– Land Reclamation – the process of restoring the land back to
its original ecosystem
• Agriculture
SOIL CONSERVATION
• Layers of Soil (from top
to bottom)
– Litter – dead leaves and
organic material
• Important for returning
nutrients to soil
– Topsoil – rock fragments,
nutrients, water, air, plant
roots
• Most important for
growing plants
– Subsoil – larger rock
fragments
– Bedrock – solid rock
• What ground water lays
on (aquifers)
PROBLEMS OF SOIL
CONSERVATION
• Erosion – the loss of topsoil by wind or water
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Usually held in place by roots of plants
Windbreaks – hedgerows
Tree buffer between field and stream
Strip cropping/contour farming
Terrace farming
• Nutrient Depletion – overusing a single piece of land,
stripping it of its nutrients
– Removing crops over and over from a single piece of land
– Fallow – leave the crops on the field
– Crop rotation – plant different crops in the field each year
• Different crops use different nutrients
– Add Fertilizer
• Natural or synthetic
PROBLEMS OF SOIL
CONSERVATION
• Desertification – climate changes and
fertile land turns to desert like conditions
– Can be caused by cutting too many trees
down (deforestation)
• Disrupts water cycle
– Solutions:
• Forest management
• irrigation
– Last 50 years – 5 billion hectares of land
The Solid Waste
(Trash) Problem
• Municipal Solid Waste – wastes produced in
homes (trash)
• Sanitary Landfill – an area designated to bury
and hold solid waste
– Must meet many regulations
– Leachate – the polluted runoff from trash mixing with
rainwater
• Leak-proof linings
– Methane gas  energy
• Incineration – burning trash
– Takes up less space than landfills
– Causes air pollution; expensive to build; Still need
landfills for ash
The Solid Waste
(Trash) Problem
• The Three “R’s”
– Reduce
– Reuse
– Recycle  glass, plastic, aluminum, paper
• Composting – promoting decomposition of
foods and other biodegradable materials
at home
– Biodegradable – a substance that can be
broken down and decomposed by bacteria
(and other decomposers)
– Can be used as a natural fertilizer
Hazardous Wastes
• Any waste that can cause extreme harm to
individuals or the environment
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Toxic – Poisonous
Explosive – react quickly with air or water
Flammable – easily caught on fire
Corrosive – eats away; dissolve
Radioactive – unstable atoms that release energy
(radiation)
• Nuclear wastes  Yucca Mountain national waste site
• Medical Wastes  cancer treatment & x-ray
Hazardous Wastes
• Health Effects:
– Short term – irritation, breathing difficulties, internal
bleeding, paralysis, coma, death
– Long term – cancer, birth defects, death
• Disposal
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Burial
Incineration
Living organisms
Recycle
• Superfund sites – areas identified as polluted
with hazardous wastes and are being treated
• BE SMART AND MAKE ENVIRONMENTALLY
GOOD DECISIONS!