Human Impact On The Environment

Deforestation or Cutting Down Trees

What are some causes of deforestation?

-Clearing land for agriculture or farming

-To build homes, schools, shopping centers

-Harvesting wood for fuel

-To make room for live stocks
-To build roads

What are some consequences of deforestation?

- lost of biodiversity

- extinction

- increase in global warming

- lost of cures for diseases and medicines that control illnesses
-less oxygen

Bio means living

Diversity means variety

Biodiversity is a compound word meaning variation of life forms

Should humans try to preserve biodiversity?

People who argue in favor of preserving biodiversity claim that it helps maintain a balance or stability in the ecosystem, preserves possible cure for illnesses and helps maintain an aesthetic balance or beauty in communities.

On the other hand, those who argue against preserving biodiversity insist that extinction is a natural process and humans should not interfere. Additionally, preserving biodiversity is expensive and this money can be put to better use.

ACID RAIN

Normal rain has a pH of 5-5.6

ACID RAIN
is when the pH of rain water is less than 5.
 
What are the causes of acid rain?

• Acid rain is caused by nitrogen oxide and sulfur dioxide released by factories burning fossil fuels (fossil fuels are fuels made by the remains of dead organisms. Ex. coal, oil, gasoline, cooking gas (methane)

What are some consequences of acid rain?

- damage to soil

- damage to buildings

- damage to plants

- kills animals that live in water (aquatic life)

DAMAGES CAUSE BY ACID RAIN

What are some steps that you can take to minimize acid rain?

- vote for politicians who support the environment

- recycling

- start a cyber letter writing campaign

- start an Internet site that addresses this problem

What is global warming?

It refers to the increase of the average temperature of our planet. This problem is caused by excess carbon dioxide that is released in the environment by burning fossil fuels.

Normally, when the sun ray hits the earth, it is reflected back into space. However, excess carbon dioxide in the atmosphere acts as an insulator and traps the sun rays and thereby preventing it from reflecting back into space. As a result, the average temperature of the earth goes up.

What are some consequences of global warming?

- irregular weather patterns (severe droughts, floods, stronger hurricanes)

- increases the rate of extinction- melting of ice caps

- loss of drinking water

DAMAGES CAUSE BY GLOBAL WARMING

What are some steps that you can take to reduce global warming?

- recycle

- take public transportation

- tune up your cars

- start a cyber letter writing campaign

- vote for politicians who support the environment

- plant more trees

- educate others about global warming

Increased Human population causes:

- increased pollution

- loss of habitat that leads to higher rate of extinction

- loss of biodiversity (possible loss of medicines and cures for diseases)

- increased global warming

Using Nuclear Power Plants

Advantages
- low carbon dioxide emissions
- the technology is readily available
- it is possible to generate high amounts of electricity within one single planet.

Disadvantages

- always a chance for accidents
- problem with waste disposal
- nuclear power plants can be targets for terrorist attacks
- waste product can be used for the production of nuclear weapons.

Questions:
How can spraying pesticide on plants affect aquatic life on near by lakes?

• The pesticide can be carried to nearby lakes by rain water

How can the introduction of new species change an ecosystem?

• The new species can bring diseases.
• May not have any predator in the new ecosystem
• Can be a predator to native species and cause extinction of native species

What is it that government can do to prevent the introduction of new species into an ecosystem?

• Government can pass laws preventing the introduction of new species into an ecosystem.
• Can enforce existing laws that regulate the import of new species

What is ecological succession?

• Ecological succession is the orderly replacement of organisms in an ecosystem.

Example of ecological succession

List some environmental factors that are carcinogenic or cause cancer.

• Some environmental factors that cause cancer are: ultra violet light or sun ray nuclear radiation, cigarette smoking, chemicals

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