Human Impact

Breaking news: World population has reached 7 billion...

Can you think of any problems this mightcause?

World Health Organisation

You have been asked by the World Health Organisation to analyse some of the data which has been collected.

To do this, you will need to use your problem solving skills.

Averages

• What has the average population of the world been over the past 60 years?

• Following an experiment, why is it better to calculate the average of your results?

Year Population (billions)

1950 2.21960 31970 3.61980 4.21990 4.92000 62010 6.9

Ratio

Express the difference in population size between 2000 and 1960 as a whole number ratio.

Express the difference in population size between 1980 and 1960 as a whole number ratio.

Year Population (billions)

1950 2.21960 31970 3.61980 4.21990 4.92000 62010 6.9

Percentages

• What percentage of the population in 2010, were alive in 1970?

• What percentage of the population in 2000 were alive in 1950?

Year Population (billions)

1950 2.21960 31970 3.61980 4.21990 4.92000 62010 6.9

Percentage Change

• Calculate the percentage increase in the population size from 1950 to 1990.

• Calculate the percentage change in the size of the population from 1970 to 2010.

Year Population (billions)

1950 2.21960 31970 3.61980 4.21990 4.92000 62010 6.9

Converting a percentage

• It is predicted that the world population in 2050 will have increased by 20% of 7 billion. By how much will it have increased?

• By 2100, it is predicted to have risen by 31% of 7 billion. What size will the population be in 2100?

Year Population (billions)

1950 2.21960 31970 3.61980 4.21990 4.92000 62010 6.9

Plotting a graph.

Year Population (billions)

1950 2.21960 31970 3.61980 4.21990 4.92000 62010 6.9

• Plot a graph to demonstrate the data

Human Population Growth

• Human population growth can have an impact on biodiversity in many ways;

• e.g. Increased demand for food. Carbon dioxide production.

Measuring Human Impact

• Human impact on the environment can be calculated by measuring our ecological footprint.

• An ecological footprint is a measure of human demand on the Earth’s ecosystems.

Human Impact Research

Green - Habitat destructionOrange - Over-fishing

Blue - Oil spills

Human Impact Research

• Explain the role of humans in your given situation.

• Give specific examples of these roles.• Explain how the biodiversity has

been affected in each situation.• Give specific examples.

Human Impact – Water Pollution

Watch the following clip about water pollution and prepare to summarise;3 ways in which water becomes polluted.

Human Impact – Water Pollution

• Water pollution can be caused by substances such as fertilisers, sewage and oil spilling into the water.

• Indicator species in the water show the environmental conditions of the water.

Human Impact – Water Pollution

• Sewage leaks into the rivers.• Bacteria feed on the sewage.• The numbers of bacteria in the river

increase.• Oxygen concentration in the river

decreases.• This causes the fish to die.

Questions

• Name some living organisms which that use sewage as food.

• In what way will the number of micro-organisms in a river change in the presence of pollution.

• How does this affect the oxygen concentration in the river?

Questions

• Explain what is meant by the term “indicator species”?

• What does the presence of bloodworm indicate about the level of oxygen in the river?

• In what way does the pollution of a river by organic waste affect the numbers of species present? Explain why.

Natural Hazards – Mind Map

• Think of as many examples of natural hazards as possible.

• How do they each affect biodiversity?

Natural HazardsNatural Hazard Effect on Biodiversity

Think, pair, share...

Why are pandas in zoos?

Should we be paying to keep them there?

Watch the following clip...

Should we let the Pandas die???

Panda Conservation

Arguments For... Arguments against...

My opinion is that..... because.............