Topic 7B Human impact on the environment

Question 1

What is Biodiversity

Answer 1

Biodiversity is the variety of different species of organisms on Earth, or within an ecosystem

Question 2

Why is it important to have a high biodiversity within an ecosystem

Answer 2

• It makes sure that ecosystems are Stable
• Different species are interdependent so they rely on each other for food and shelter
• High biodiversity makes it less likely that a species has to rely on a single different species to provide the resources and physical environment that it needs. There is more chance that another species in the ecosystem can provide the same resource and conditions required

Question 3

True/False The population of the world is decreasing but the standard of living is increasing

Answer 3

False Both the population and the standard of living are increasing mainly due to modern medicine and farming reducing the no of people dying form disease and hunger and the use of raw materials to make luxury items i.e. cars, computers, oil, plastics

Question 4

How can chemicals used to grow crops cause water pollution.

Answer 4

Chemicals used on land to help grow plants can be washed into water.

• excess fertiliser added to field washes into lake/river
• Nutrients in fertiliser cause algae to grow algae bloom
• The bloom blocks out sunlight for other plants in the water inhibiting their photosynthesis
• The dead plants are fed on by microorganisms which use up more oxygen in the water
• this affects the fish and other animals which require oxygen to survive and can lead to death

Question 5

What is land pollution

Answer 5

Land pollution is the deposition of solid or liquid waste materials on land or underground in a manner that can contaminate soil and ground water

Question 6

How is land pollution caused by humans

Answer 6

By using toxic chemicals for farming (Herbicides, Pesticides) and by burying toxic waste and creating landfill sites for waste

Question 7

What is Air pollution give an example

Answer 7

The release of smoke or acidic gases released into the atmosphere which can pollute the air
- The burning of some Fossil fuels releases CO2, the increasing levels of CO2 is contributing to global warming and climate change

Question 8

Suggest why the amount of space taken up by landfill sites around the world is increasing

Answer 8

Due to the increase in population which in turn creates an increase in the amount of waste we produce some of which is dumped into land fill
As the standard of living increase the more waste is produced and increasing the amount dumped into land fill

Question 9

Suggest one reason why it is important to recycle products such as metal cans

Answer 9

As the population increases we use more raw materials. It is important to recycle products so that we don’t run out of raw materials it also reduces the amount of waste sent to land fill

Question 10

Give a brief overview of global warming and the green house effect

Answer 10

Green house effect:

• Energy from the sun is absorbed by the earth
• The earth radiates this energy back out into the atmosphere
• Greenhouse gases (CO2 and Methane) in the atmosphere absorb the energy creating an insulating layer
• The gases re radiate the energy in all directions including back down to earth which increases the temperature of the earth

Global warming is a form of climate change which refers to the temperature increase on earth due to the increase in greenhouse gases

Question 11

How do human activities increase the amount of Methane and Carbon dioxide in the atmosphere and how does this contribute to global warming

Answer 11

Deforestation:

• Cutting down of forests to grow crops and clear land for cattle. Trees and plants absorb Co2 during the photosynthesis process. If there are fewer trees and plants, due to deforestation, then less carbon dioxide is removed from the atmosphere.
• The burning of forest in order to clear land for cattle releases carbon from the wood.
• Microorganisms also feed on the dead pieces of wood and in turn release carbon dioxide as a waste product of respiration

Question 12

How does global warming lead to changes in the distribution of organisms

Answer 12

• Organisms are found in places where they can survive.
• If the average global temperature increases due to global warming the distribution of organisms may change
• Organisms that require hotter temperatures may become more widely distributed as the conditions they thrive in are more common over a wider area
• Organisms that require colder temperatures in order to thrive may become less widely distributed as they may have a smaller range of conditions to thrive in over a smaller area

Question 13

How might global warming affect bird distribution

Answer 13

Global warming could cause changes in bird migration patterns causing birds to leave or stay in a country for longer or shorter periods of time. If some bird species fail to adapt to the changes in their environment caused by global warming there is a chance they could die out.

Question 14

Give Four consequences of global warming

Answer 14

Rising sea level - As the sea gets warmer, it causes the sea level to rise This could lead to flooding of low lying places resulting in the loss of habitats (where organisms live)

Changes in Distribution - the distribution of organisms is jest where they are found in a certain area.These areas have the right temperatures and resources, shelter, food for the organism to survive. As global warming happens, organism distribution can change. Organisms which require higher temperatures may become more widely distributed as they have a wider area to exist in.

Less Biodiversity - Biodiversity (variety of plants and animals in a particular habitat) could be reduced as some species of organisms may be unable to to adapt to changes in environment caused by global warming e.g. higher temperature means they cant live in their normal habitat but other habitats don’t have the right food so they may die

Changes in migration patterns

Question 15

Give four things that humans use land for that reduces the use of land for other animals

Answer 15

Building
Farming
Quarrying
Dumping waste

Question 16

What is deforestation

Answer 16

The cutting down of forests

Question 17

Give the different kind of farming that might be taking place on land cleared through deforestation

Answer 17

• Cattle farming
• Growing crops
• Growing crops to create bio fuels

Question 18

Dave is a gardener who wants a peat free alternative compost for his crops. explain why a peat free alternative is environmentally friendly

Answer 18

Peat is extracted from bogs (areas of water logged land). Peat bogs store carbon instead of releasing it into the atmosphere as carbon dioxide. If peat bogs are destroyed for the use of peat compost, the carbon dioxide will be released contributing to global warming. therefore a compost which doesn’t require the destruction of bogs could be considered environmentally friendly

Question 19

What is a breeding programme and what is its purpose

Answer 19

A breeding programme is an initiative set up to help prevent endangered species from becoming extinct. Animals are bred in captivity to ensure the species survives if it is dying out in the wild. Organisms can sometimes be released into the wild to boost or re-establish a population.

Question 20

Outline and explain what a farmer who only grows one crop might do to protect and promote biodiversity

Answer 20

Hedgerows and field margins can be introduced around the farmland in order to protect biodiversity. They help to provide a habitat for a wider variety of organisms than could survive in a single crop habitat

Question 21

Name some of the protection programmes in place to help maintain biodiversity

Answer 21

Breeding programmes - to prevent species from becoming extinct

Programmes to protect an regenerate rare habitats in turn protecting the wildlife that lives there.

Programmes to reduce the levels of deforestation taking place and the amount of carbon dioxide being released into the atmosphere which in turn could help reduce global warming.

Question 22

Give one reason why people are encouraged to recycle as much waste as possible

Answer 22

This helps to reduce the amount of waste which is dumped into landfill, in turn reducing the amount of land taken over for landfill and so leaving ecosystems in place

Question 23

Mangroves are forest like ecosystems found in tropical areas. They are close to water and often flood with sea water when the tide comes in.
Enormous areas of mangroves have been destroyed to make way for large scale shrimp farming.

Suggest why projects to protect areas of the mangroves from shrimp farming may be subject to pressure which could affect its success.

Answer 23

• It would cost money for the government to monitor whether people were sticking to the programme.
• The local economy would be negatively affected as locals earning a living from the shrimp farms would have to find work else where