Science by Email 30 March 2012

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	30 March 2012
News: Banking on our future By Patrick Mahony Trees are able to store large amounts of carbon in their trunks, branches, roots, leaves and bark. Rising carbon dioxide levels in the Earth’s atmosphere are one of the main drivers behind climate change. We can reduce our emissions of carbon dioxide, but what about future emissions and the carbon dioxide already in the atmosphere? How about removing the carbon from the atmosphere, converting it to a stable form and storing it in a carbon bank? This process is called biosequestration and plants have been doing it for millions of years. Photosynthesis uses carbon dioxide to produce sugars which are then used by the plants to grow. Trees are particularly good at storing carbon in their trunks, branches, roots, leaves and bark. Once the trees are fully grown they can be cut down and the timber used to make houses and furniture, keeping the carbon locked up for a long time. More trees can then be grown to store even more carbon. Tree banks are one way to store carbon, but we can’t just cover all land with trees – we still need clear land for agriculture. Luckily there’s another carbon bank, right under our feet: it’s soil. Soil carbon can be increased through the decay of plants, microbes and manure. Research is currently underway to see how farmers can change their agricultural practices to increase soil carbon and lower carbon dioxide in the atmosphere. Banking all this carbon in trees and the soil could help lower carbon dioxide levels in the air and reduce the negative impact of climate change. But it’s not just farmers and scientists that have to worry about sustainability. Other companies can promote sustainability in the way they conduct their business, investing in environmentally sustainable projects and supporting community-based initiatives. Sustainability and climate change are not somebody else’s problem. But it is a problem that all sections of the community, including individuals, farmers, scientists and businesses can work together to solve. More information CSIRO: Managing carbon in forests Trees for carbon sequestration Reducing greenhouse gas emissions using soil carbon bankmecu and sustainability bankmecu's conservation landbank CarbonKids Careers link Careers in climate change research
You will need these materials.   Break the eggs in two over a bowl.   Boil the shells for a few minutes. Allow to cool, then remove the 'skin' on the inside of the shell.   Place the 2 cups of warm water and 1 cup of Epsom salts into a microwave safe bowl. Stir to dissolve then microwave on high for 3 minutes. Stir until you have a clear solution.   Transfer the warm solution into different containers and add different food colouring and a shell to each container.   Allow to soak for about an hour, then put on rubber gloves and remove the shells. Put them in an egg carton and carefully fill the shells with solution then allow the liquid to evaporate.   Try this: Egg geodes Safety: This activity involves heat and hot water. See the CSIRO Education safety page for more information. You will need Raw eggs Empty egg carton Water Mixing containers Food colouring Epsom salts Saucepan Oven mitts Bowls Measuring cups Metal spoons Slotted spoon Ladle Rubber gloves What to do Break the eggs in two over a bowl. You can cook the eggs and eat them, or use them in another recipe. Carefully rinse the inside of the shells to remove the egg white and yolk. Put a few shells into water in a saucepan and boil them for several minutes. Carefully remove the egg shells using the slotted spoon and allow them to cool. The ‘skin’ inside the shell should peel away with some care. After the skin is removed, the shells are fragile, so handle them gently. Put 2 cups of warm water into a microwave-safe bowl. Add 1 cup of Epsom salts into the bowl and stir until as much as possible has dissolved. Put the bowl in the microwave, and heat on a high setting for 3 minutes. Remove the bowl from the microwave using the oven mitts and stir the solution until all the crystals have dissolved. The solution should be clear. Allow the solution to cool for 10 minutes. Carefully ladle the warm solution into different containers, one for each colour. Add a few drops of food colouring to each. Put the egg shells into the containers and allow them to soak for about an hour. Put on some rubber gloves and remove the shells from the solution. The shell should absorb a bit of colour, and you might already see some crystals forming. Put your eggshells into an egg carton to hold them steady. Carefully pour one of the coloured solutions into a shell until it is full. Repeat with the other mixtures in different shells. Put the filled shells somewhere warm and well-ventilated. The water will evaporate and leave crystals. Check them every day to see how your crystals are going. If a crystal skin forms over the top, gently break it so the liquid trapped underneath can evaporate. What’s happening? When you dissolve a solid substance in liquid, the solid particles separate and spread out. The substance being dissolved is called a solute and the liquid is called a solvent. When you put in as much solute as the liquid can hold, the mixture is saturated. By heating the water you can dissolve more solute than water at room temperature. When the water cools down it holds more solute than a saturated solution, so it’s said this mixture is supersaturated. When you leave a saturated or supersaturated solution to dry, the liquid evaporates and the solute becomes solid again. The particles of solute join with one another like tiny building blocks. If the mixture dries slowly, the solute particles have time to line up more precisely, forming crystal shapes. Different solutes will form different crystals. Salt crystals are cubic and sugar crystals are hexagonal, flat and thin. Epsom salts usually grow long thin crystals. Applications Your eggs are a model for natural hollows in rocks that contain crystals, called geodes. Holes in rock are often created by bubbles of gas in hot magma that has since cooled. Water filters through the surrounding rock, dissolving materials as it goes. When it gets into the rocky hollows, water can deposit solute and leave tiny crystals on the inside. Over millions of years the crystals grow. Sometimes they can fill the entire rock. When this happens it is called a nodule. The most common crystals in natural geodes are quartz and calcite. By Deb Hodgkin CREST question: Is is possible to make similar egg geodes with other kitchen substances? Design and carry out an investigation to test this.   Try another Science by Email activity about making crystals More information The Crystal Caves in Queensland Geodes World’s largest known crystals View the online version Quiz questions 1. After nitrogen and oxygen, what is the most abundant gas in the Earth’s atmosphere? 2. What are the longest cells in the human body? 3. In computer science, what does GB stand for? 4. Astronomers recently linked up telescopes in Australia and South Korea. How many telescopes in total were connected? 5. What is pertussis more commonly known as? Did you know? The Alcubierre warp drive is a theoretical device that would allow space travel by warping the space-time continuum around a spaceship. Unfortunately, according to calculations by University of Sydney scientists, such a device would have devastating effects on the crew and destination. Websites   Do it! Just how much carbon can a tree store? Find out using this calculator! Hear it! One tree can store carbon but forests can store even more. Find out just how much on CSIRO podcast. Happy Easter! Next week is the Easter long weekend. As a result, there will be no Science by Email next Friday 6 April. Science by Email will return the following Friday 13 April.                                                           In the meantime, have a happy and safe Easter break! Events National: Fascination of Plants Day Plants: we may take them for granted, but they can be truly fascinating. To celebrate Fascination of Plants day, Australian secondary students have a chance to win $1000 in a plant science video competition. To enter, individuals, groups or classes can make a three-minute video showing why plants are fascinating. Entries close 18 May 2012. For more information, go to the Fascination of Plants Day website. Border protection, Saturday 31 March at 9.00 am on Network Ten Each year, millions of travellers enter Australia through our airports and seaports. Add to that 20 million tonnes of cargo and more than 150 million items of international mail, and you begin to realise that protecting our borders is a pretty big job! Join Dr Rob as he goes behind the scenes at customs, once again proving that the ordinary becomes extraordinary, under the SCOPE. Next episodes: Thursday 5 April: Weird body stuff Saturday 7 April: Underwater science Want to have your own episodes of SCOPE to watch whenever you feel like it? Click here to download them directly into your iTunes folder, or go here to download iTunes. Charges apply. Quiz answers 1. Argon is the most abundant gas in the Earth’s atmosphere after nitrogen and oxygen. 2. The longest cells in the human body are sensory neurons, which can be up to 1.5 metres long. 3. In computer science, GB stands for gigabyte. 4. Five telescopes in Australia and South Korea were connected. 5. Pertussis is commonly known as whooping cough. Recent research suggests that a rise in the number of whooping cough cases in Australia may be due to the emergence of a new strain of the bacterium that causes pertussis. Science by Email is a CSIRO publication. The Department of Agriculture, Fisheries and Forestry and bankmecu are proud partners of Science by Email. 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