We will review how humans are

hurting & helping the

environment

living things ( ) nonliving things

( )

The . Ex: rocks, temperature, sunlight, water, air wind etc.

The Earth’s ex: frogs, trees, birds, fish, the

decomposers, !

Limited resources:

such as oil, coal, iron ore, aluminum, food and soil…..

of resources:

.

in a reasonable amount of time.

.

Sunlight is renewable because the sun shines everyday.

Animals are renewable because they make babies

Plants are renewable because we can plant seeds.

Water is renewable because of the water cycle.

in a reasonable amount of time. ex: fossil fuels and minerals.

Fossil fuels ( coal, petroleum, oil & natural gas) took millions of years to form from ancient plants & animals. They CANNOT be recreated once they

are used up!!!!!

Minerals (iron ore, aluminum, silver etc) were made billions of years ago in stars that went supernova! when they are depleted (used up), they cannot be renewed.

Preserving natural resources: , and

:

• Turn off lights you DON’T need.

• Walk or bike ride instead of driving.

• Use renewable (alternative) energy like solar power, wind-power or water power.

• Carpool

• Take public transportation

Turn off lights when you don’t need them.

Use wind power

Use solar energy or water power

Find alternate means of transportation…

walk

or ride a bike

Take public transportation.

Carpool!

carpool

Humans think that we are apart from nature, because we have

technology.

But humans rely on the natural processes of nature to keep us alive.

a natural process called photosynthesis makes our oxygen (and food).

Weathering and erosion created the soil we use to grow our crops.

The water cycle provides our drinking water.

The nuclear fusion in the sun creates the sunlight that heats and powers our

ecosystem.

Now answer 1- 15

What are the following pictures saying?

The human population has grown tremendously in the last few centuries.

Technology is the cause of human population growth.

better food, medical care, better sanitation have helped humans to live longer and have more children that survive

to adulthood.

The increase in human population has hurt the environment and endangered other

species.

This graph shows organisms at equilibrium around the environment’s

carrying capacity….

Humans live beyond Earth’s carrying capacity!

When the human population increases: they cut down forests, destroy grasslands and wild areas to build apartment houses, schools, shopping malls, make more farms,

build factories etc…

As the human population increase, pollution, habitat-destruction and

mass extinctions increase!

Now answer 16- 24.

Human activities can be harmful for the environment:

Deforestation, over harvesting, introduction of imported (invasive) species, pesticides use, fertilizer use, air pollution, water pollution, industrial wastes,

1. deforestation: destroying forests by cutting down many many trees.

Deforestation destroys animal’s habitats, increase carbon dioxide in air, destroys rare species and new medicinal plants..

Solutions to deforestation:

• Cut down less trees.

• plant more trees to replace cut ones.

• Pass laws to prevent over harvesting of trees.

• Created protected forest areas where NO ONE can cut.

2.Over harvesting (Over hunting, over fishing): exploiting an organism too

much.

Ex: elephants killed for

tusks and left to rot!

Over harvesting (Over hunting, over fishing) can lead to endangered or

extinct species.

Ex: elephants killed for

tusks and left to rot!

Solutions to Over harvesting (Over hunting, over fishing):

• Pass laws to protect animals.

• Do not hunt too many animals.

• Create protected areas for animals.

3. Imported species (invasive species): taking animals from their natural home and

putting them in a new environment without any natural predators.

Examples of Imported species: rabbits & the Cane toads in Australia.

24 European rabbits were brought on purpose to Australia, they had no natural enemies. They bred and bred and bred until there were

thousands (millions?) they almost destroyed Australia’s ecosystem.

cane toads were brought on purpose to Australia, they had no natural enemies. They bred and bred and bred until there were thousands

(millions?) they almost destroyed Australia’s ecosystem.

sometimes imported species are brought by accident: the zebra mussel, gypsy moth, Japanese beetle, the fire ants.

sometimes imported species are brought by accident: the zebra mussel, gypsy moth, Japanese beetle, the fire ants.

All are threats in their new environments!

Solution to imported (invasive ) species:

• Don’t remove animals or plants from their natural habitats.

• Pass laws against importing species.

Now answer 25- 47.

Pests threaten our food, our crops, our health and are just “yucky”…

Pesticides have helped us get rid of weeds.

Pesticides (bug spray) has helped humans to fight against pests…..

But pesticides don’t only kill the pests, they are harmful to other organisms too!

If it can kill the bugs, it can kill

anything!Including me!

the pesticides are poisons get into the ecosystem, poisoning “innocent” life

forms, even humans. !If it can kill the bugs, it can kill

anything!Including me!

“innocent” organisms face extinction because of pesticide spraying; also some pests have evolve

immunity against the pesticides!If it can kill the bugs, it can kill

anything!Including me!

Now answer 48- 55

Technology: has improved the

quality of life for humans…

Humans need electricity to run our machines…. But there are tradeoffs

(consequences)

Producing electricity (a good thing) is mostly made in “bad ways”: burning fossil

fuels & nuclear energy.

The Fossil fuels are coal, oil, gasoline and natural gas…

Burning fossils fuel releases carbon dioxide (CO2) and other “greenhouse

gases”.

Nuclear energy does NOT pollute the air, but the radioactive wastes remains deadly for tens of thousands of years!

Solutions: make electricity using alternative sources:

• Solar energy

• Wind power

• Hydroelectric (water) power.

• Conserve electricity (turn off lights/appliances when you DON’T need then)

industrialization has improved the quality of life for humans…

Factories produce clothes, TV’s, DVD’s, computers, furniture…

But there are trade-off (negative consequences)….

Factories produce air pollution, water pollution, solid waste.

Air pollution: poisonous gases released into the air from factories or from

cars.

Air pollution is bad because it: causes global warming, ozone layer- depletion

& acid rain!

global warming: carbon dioxide (CO2) and other greenhouse gases are raising average

global temperatures; leading to severe unpredictable weather, the ice caps

melting, rising sea levels and flooding.

CO2 levels have risen tremendously in modern times. This is associated with

global warming!

Before After?

The ozone layer protects us from UV radiation.

CFC gases from spray cans deplete (destroy) the ozone layer. levels of skin cancer may rise without ozone

layer protection!

acid rain: car exhaust, factory smoke, forest fire smoke add chemicals to the air. The

chemicals mix in the clouds and fall as acid rain.

Acid rain is bad because it destroys plants, kills fish when it gets in water and damages statues and buildings

Solutions to air pollution.

• Don’t pollution the air.

• Make air pollution laws.

• Don’t use spray cans that have CFC’s in them.

• Recycle.

• Plant trees to take CO2 from the air.

• Build less factories.

• Electric cars that don’t pollute.

Water pollution: some factories produce wastes, which are dumped into the lakes,

rivers and oceans.

Solutions to water pollution:

• Don’t pollute the water.

• Recycle.

• Build less factories.

• Treat sewage.

Fertilizers help our plants to grow.

Sometimes fertilizers wash into our rivers, lakes and oceans when it rains… the fertilizers kill fish or cause toxic algal

blooms that also kill fish.

Solutions:

• Avoid over use of fertilizers.

• Be careful not to let fertilizers wash into lakes, rivers or oceans.

Now complete 88- 117.