Earth and Space Sciences Resources: Renewing our interest

You need resources to do anything – paper to write on, electricity to recharge your phone, food just to stay alive. Some of our resources can’t be easily replaced and might run out. Using some resources harms the environment, such as climate change caused by burning fossil fuels. Some scientists are coming up with ways of reducing the harm done by fossil fuels and others are developing alternative sources of energy. In this lesson you will investigate the following: • What’s the difference between renewable and non-renewable resources? • How will we meet our energy needs in the future? • What makes our use of some resources unsustainable? • What would you need to set up an egg farm? See if you have the resources needed to complete this lesson!

This is a print version of an interactive online lesson. To sign up for the real thing or for curriculum details about the lesson go to www.cosmosforschools.com Introduction: Resources

What would you do if you found yourself trapped alone on an island? There are no houses and no people to cook you meals or buy you clothes – and no shops where you can buy them for yourself!

All you have are the natural resources you discover on the island: water, plants, animals, rocks, air and sunlight. Your survival depends on how well you use them to supply what you need – shelter, food, tools, and so on. Above all, you need to make sure that you can replace what you use so you don’t run out.

The Earth is just an island floating in space. Everything that we humans need has to be found somewhere on the planet. And our survival depends on how well we use its natural resources.

One of the things we need in huge amounts these days is energy. Our cars, planes, TV’s and air conditioners are all thirsty for it. Most of our energy comes from burning coal, oil and natural gas but there are two main problems with these fuels.

The first is that supplies are limited and will take millions of years to be replaced by natural processes. This means that we’ll use them up within a few generations.

The second problem is that burning these fuels is changing our climate by adding to the amount of carbon dioxide gas in the air. Some countries are now trying to capture the gas and store it deep underground where it can’t pollute the atmosphere.

But this can’t fix the first problem and we’ll have to rely more and more on sources of energy that won't run out, such as sunlight, wind and flowing water. Only by understanding the natural resources we rely on every day can we hope to survive on our island planet.

Read or listen to the full Cosmos Magazine article here.  Question 1

Describe: Open your school bag and place the contents on the desk in front of you. These objects are just some of the resources you bring to school so you can study. Other resources are supplied by your school – for example, the buildings that protect you from sun, wind and rain or the chairs you sit on.

List all the resources you need to study at school and see if you can also write down some of the materials needed to make them.

Resources provided by you Materials Resources provided by your Materials school Gather: Resources

0:28

Natural resources The 3,000 km long World Solar Challenge is a car race with a difference. Instead of burning petrol, the futuristic cars use solar panels to collect energy from the Sun! The race sparks interest in new uses of our resources.

Every day you rely on certain things to keep you alive and healthy – air, food, water, warmth and shelter, for example. All of these are natural resources that need to be supplied by the world around you. They can be divided into two categories:

Renewable resources can be replaced by natural processes within a lifetime – that is, about 80 years. Non-renewable resources take longer to be replaced and so are more likely to be used up.

The sunlight used by cars in the World Solar Challenge is a renewable resource. This is because the Sun shines continuously and will continue to do so for billions of years. The petrol used by ordinary cars is a non-renewable resource – you'll discover why a bit later on.

Left: Solar-powered computers are used in schools and rural communities in Uganda, Africa. Right: Design for a "solar tent" that would allow campers to use solar energy to recharge their phones and other electronic devices. Renewable energy Energy is one of our most important resources. It comes in a wide variety of forms, both renewable and non-renewable, but first we will look at some renewable forms.

When energy comes directly from the Sun as light and heat it is called solar energy. Plants use solar energy to create food, making this renewable resource essential for almost all life on the planet.

 Question 1  Question 2

Decide: Energy from the Sun is a useful resource because: Remember: Solar energy is renewable because:

it provides warmth to humans and other animals. it can be converted into electricity.

it provides light so we can see. it's replaced quickly, in less than a human lifetime. it is used by plants to produce food. it takes millions of years to be replaced. All of the above. it's only available during the daytime.

 Question 3

Identify: Name one advantage and one disadvantage of solar-powered cars compared to petrol cars.

Some other types of renewable energy are described in the video below. The word "kinetic" describes the energy that something has whenever it moves. In contrast, "potential" energy is energy that is stored up and then released later.

2:01  Question 4

Complete: Use information from the video to name one advantage and one disadvantage of each type of renewable energy.

Note: A lot more could be said about the advantages and disadvantages of these forms of renewable energy.

Type of renewable energy Advantage Disadvantage Wind Water – wave May harm the nearby marine environment. High cost of maintaining the equipment in rough seas. Water – tidal Water – hydroelectric dams Geothermal Solar Generates less energy on cloudy days and none at night.

The Tavan Tolgoi coal deposit in southern Mongolia is one of the largest in the world.

Non-renewable energy Although renewable energy sources are becoming more widely used, over 85% of the world's energy in 2012 was still supplied by non-renewable sources. There are two main types of non-renewable energy that are used to generate electricity:

Fossil fuels – coal, oil and natural gas – are burned in traditional power plants. Nuclear energy relies on limited supplies of minerals containing unstable elements such as uranium.

We'll focus here on fossil fuels and start by taking a look at how they are formed. 2:25

 Question 5

Label: The process that forms fossil fuels is shown below. Use the following labels to fill in the blanks:

natural gas | plants | pressure | coal | heat | oil

 Question 6

Explain: According to the video, how long does it take for heat and pressure to turn buried plants into fossil fuels? Use your answer to explain why fossil fuels are a non-renewable resource. Did you know?

Burning fossil fuels releases carbon dioxide (CO2 ) back into the atmosphere after being trapped in fossilized plants for millions of years. This adds to global warming which is expected to raise sea levels and increase the risk of droughts and tornadoes, among other things.

The Cosmos Magazine article explains how the United States and China are now trying to "capture" that carbon dioxide and store it underground.

But even if these plans succeed, fossil fuels are a non-renewable resource and are expected to run out in 50 to 100 years. So the pressure to develop renewable energy sources remains.

 Question 7

Classify: Identify whether each of the following sources of energy is renewable (R) or non-renewable (N). Process: Resources

Left: Veta la Palma is a sustainable fish farm in southern Spain that is also home to threatened bird species. Right: A farm in Port Augusta, South Australia, that uses desalinated seawater and solar power to grow tomatoes.

Sustainability Energy is just one of the natural resources that we rely on every day to meet our needs. Others include:

air water rocks minerals soil living things

Understanding whether these resources are renewable or not is important. If we use a resource more quickly than it can be replaced then sooner or later it will run out. This might create a serious problem for us or for our children and grandchildren.

Some of the ways we use resources are sustainable, which means that we can keep using them for generations without using them up.

Most renewable resources are sustainable – but not always. For example, salmon are a renewable resource because they can be replaced by a new generation each year. But overfishing has caused the population of wild salmon to decrease dramatically because they can't be replaced quickly enough to meet demand. Most non-renewable resources are unsustainable – but not always. For example, soil is a non-renewable resource because it often takes centuries to form. But we can still use soil sustainably to grow vegetables if we protect it from being washed or blown away and use fertilizers to replace the nutrients.

To explore these ideas more we'll jump on a plane and go on a journey... Welcome to the beautiful island nation of Dijali, a land of soaring mountains and dense forests. You've been invited to investigate our country's natural resources and decide whether the way we use them is sustainable. Our growing population needs more and more resources. How much longer can we preserve our way of life?

Minerals Early explorers of Dijali discovered coal and iron ore in its mountains as well as precious minerals such as gold and diamonds. These minerals were formed over millions of years by extremely slow processes deep in the Earth. Many are now shipped out to other countries through our bustling port and are a great source of wealth.

 Question 1

Explain: Are minerals renewable or non-renewable? Explain your answer.

 Question 2

Propose: Dijali's iron ore mines have been operating for 200 years, taking out the iron needed to make machines, tools, ships and countless other things. Local scientists estimate that if mining continues at this rate then the deposits will run out in the next century. Is our use of iron sustainable? If not, suggest other ways we could meet our needs. Forests Another important natural resource in Dijali is wood. This is used to make furniture and buildings, as well as things like paper, tissues, matches and firewood. Thankfully, the island is covered in trees: thick rainforests along the coast and pine forests on the mountain slopes.

 Question 3

Classify: There are still large areas of dense rainforest along our coasts that haven't been touched by humans. These are known as old growth forests and they are home to a very wide variety of plants and animals. It takes several hundred years to replace old growth forests after they've been logged.

1. Are they a renewable or non-renewable resource? 2. Do you think logging them would be sustainable?

 Question 4

Explain: Most of the logging in Dijali these days takes place in special plantations of pine trees in the mountains. These grow much more quickly and can be replaced within 20 years. Explain why this type of logging can be considered sustainable. We use living things in many ways, including cotton for sheets and duck feathers for pillows, leather for shoes and bags, and honey for food.

Living things As well as our forests, we rely on a wide range of living things to provide natural resources. Food is provided by crops such as bananas, sweet potatoes, nuts, berries and spices, as well as animals such as fish, cows, pigs and ducks. We also make a delicious soup out of the warty toads that live in the rainforests – you really should try it while you're in the country!

Ducks are farmed for their eggs, feathers and meat. Warty toads can't be farmed because they only live in the special conditions created by the rainforest. The estimated numbers of ducks and toads on the island over a 50-year period are compared in the table below.

Year Duck population (in thousands) Warty toad population (in thousands) 1960 246 285 1970 220 232 1980 235 193 1990 242 150 2000 231 122 2010 240 86  Question 5

Graph: Use the numbers given in the above table to construct a graph. Use green circles for the number of ducks and orange diamonds for the number of warty toads. The two populations in 1960 have been added to start you off.

Comparison of duck and toad populations in Dijali  

300300 Ducks

250 1960 246

x y 200

150

100 Population (thousands)

50

0 01960 1965 1970 1975 1980 1985 1990 1995 2000 1960 2010

Year

 Question 6

Describe: Describe the two lines on the graph you have created. Are the populations of ducks and toads generally stable or are they increasing or decreasing – and by how much?

 Question 7

Compare: Ducks and toads both reproduce each year.

1. Are they renewable or non-renewable resources? 2. Compare their use on Dijali in terms of sustainability.  Question 8

Propose: What are the possible explanations for the change in the toad population? For each explanation suggest how you could test it scientifically. Apply: Resources

Project: Laying plans for an egg farm

How often do you wonder about where your food comes from? What resources would you need if you had to produce it yourself?

We'll investigate this second question by looking at one example: eggs.  Question 1

Brainstorm: What natural resources do you need to start an egg farm? Obviously you'll need chickens. But what will you need to keep your chickens alive and healthy?

Add as many different resources as possible to the mind map below. Some might need further resources – add these as well, as shown in the example.

trees

wood

iron stone shelter

Resources needed to raise chickens

When you've added as much as you can, talk about your answers with your classmates. Your teacher might lead a class discussion so that everyone's answers can be pooled together. Was there anything you forgot to think about?

Suppose you have 50 chickens and now need to find a place to set up your egg farm. You have to choose between two valleys in different regions and can only use the natural resources found locally in your chosen valley.  Question 2

Identify: You travel out to each of the valleys to see what natural resources they have. Label the resources shown in the sketchpad – two have been labelled for you.

Hint: Don't forget basic things like air.

iron

grass/hay

Shelter We'll start by thinking about how to protect your chickens from the elements – wind, rain, sun – and for that you'll need to build a henhouse. But unless you plan to keep them caged up inside all the time, you'll also need an area for them to run around outside.

Now a problem comes up – predators! Animals such as foxes and snakes will make a tasty meal out of your precious birds unless you build a fence, wall or other barrier to keep them out.

 Question 3

Classify: For each of the two valleys, write down the resources that you could use to build a henhouse and fences, assuming that you have the necessary skills and tools. For each one say whether it's renewable or non-renewable – you might need more building materials to repair or expand your farm in the future!

Valley A Resources Renewable? Valley B Resources Renewable?

Water A chicken without water will die within a day. Your farm will need to be close to a reliable water supply unless you want to spend your days hauling water around the valley.  Question 4

Calculate: It rains a lot in Valley A so water shouldn't be a problem there. In Valley B the rain is more unpredictable but enough to maintain a small lake through the whole year.

1. Suppose that each of your 50 chickens needs 200 litres (L) of water per year. How much water will the whole flock need in a year? 2. The lake in Valley B gets 15,000 L of water per year and loses 4,000 L to evaporation. If you build your egg farm here will its water supply be sustainable?

Food Luckily, chickens eat just about anything! They need a good supply of grain but will also gobble up vegetables and food scraps, and scratch around for worms, bugs and seeds.

 Question 5

Compare: Compare the two valleys in terms of their food resources. Which do you think is more likely to provide a sustainable food supply and why?

 Question 6

Explain: Explain why feeding your chickens the leftovers from your own meals is a good use of resources. Compare this to the recycling of things like plastic and paper – why does this make our way of life more sustainable?

Picturing your farm

 Question 7

Draw: Decide which of the two valleys would provide the best resources for your egg farm. Create a drawing of what you imagine your farm will look like, labelling all of the resources that you would use. Take a photo of your drawing and upload the file into the project space below, or use the sketchpad tool to make your drawing. Career: Resources

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 Question 1

Think: E​ mily Potter explains how her company sets up renewable energy supplies for people who don't want to use electricity provided by power companies. As a program manager, part of her role is to make sure all the engineers in her company work together as a team.

Why do you think teamwork is important in a company? Do you think you have the qualities needed to lead a team? Why or why not? You might like to think about sporting teams, orchestras or other groups you've been involved in.

Cosmos Lessons team

Lesson author: Jim Driscoll Introduction author: Campbell Edgar Editors: Campbell Edgar and Jim Rountree Art director: Wendy Johns E​ ducation director: Daniel Pikler

Image credits: iStock, Bernd Nordhausen, Brucke- Osteuropa, Sundrop Farms, Eco Citizen Australia, Flixnn Blog, Phillip Harms, Herminio Muñiz, Carnegie CETO Wave Energy Technology, Mike Baldwin Video credits: World Solar Challenge, DoodleScience, Earth: The Operators' Manual, Career Girls, YouTube.