Rocks and Soils Soil formation This lesson we

Rocks and Soils Soil formation This lesson we are going to explore what soil is and how it is formed. Click the above link to hear a message from Ms Green

We are learning to: • explain how soil is formed. Success criteria • I can state that soil is composed of different things. • I can describe the 4 processes of soil formation.

Key vocabulary Soil formation organic matter top soil base rock additions losses translocations transformations. Keep an eye out for this key vocabulary – make a note of what they all mean as we go through and we will revisit this at the end sub

What is soil? What is soil made from? Do you know? What do you think? Tell someone close to you what you think soil is made from. Go outside and find some soil – look at it carefully, have you changed your mind about what it is made from?

What Is Soil Made Of? Soil is the uppermost layer of the Earth. It is a mixture of different things. Air Soil contains gases such as carbon dioxide, oxygen, nitrogen, methane and radon. Mineral The minerals in soil come from finely broken down rock. Water Air and water fill the gaps between particles of soil. Organic Matter Organic matter includes both living and decaying animals and plants.

These are the layers of soil

Soil Formation There are 4 main processes involved in soil formation: Things get added to the soil Additions Losses Translocations Transformations The soil is moved around Photo courtesy of expansion 1234 and Kenneth Allen (@flickr. com) Walter Baxter (@geography. org. uk) and Pretty/Ugly Design (@commons. wikimedia. org) - granted under creative commons licence – attribution Things get removed from the soil Things within the soil which change

Soil Formation Additions Rainfall adds water. Dust adds minerals. Animal waste adds organic matter and nutrients. Decaying plants and animals add organic matter. Humans add fertiliser. Fertilisers contain minerals and nutrients. Natural fertilisers are made from animal waste and organic matter. Human-made fertilisers are made from chemicals. Photo courtesy of expansion 1234 (@flickr. com) - granted under creative commons licence – attribution

Soil Formation Losses Water evaporates (turns into gas when hot) into the air. Soil particles can wash away in storms. Organic matter can turn into the gas carbon dioxide. Nutrients and Minerals are taken up by plants and can drain into groundwater. Photo courtesy of Walter Baxter (@geography. org. uk) - granted under creative commons licence – attribution

Soil Formation Translocations are movements within the soil. Gravity pulls water down from top to bottom. Evaporating water draws the minerals up from the bottom to the top. Animals living in the soil move the soil around in every direction.

Soil Formation Transformations occur when something changes into something else. Humus is what is left when dead leaves decompose. Weathering causes hard rock to erode and turn into smaller and smaller pieces of rock. Oxygen reacts with the minerals such as iron which can make the soil look a reddish, ‘rusty’ colour. Photo courtesy of Kenneth Allen (@commons. wikimedia. org) - granted under creative commons licence – attribution

Soil Formation – Fun Facts Soil is formed over long periods of time. All four soil formation processes are taking place at the same time ALL the time! . It takes at least 500 years to form just 2. 5 cm of soil! 1 cup full of soil has more organisms in it than there are people on earth!

Compost is organic matter that has been decomposed so that it can be recycled as natural fertiliser. Many people choose to have a compost bin at home as they see it as more environmentally friendly to recycle waste food rather than throw it away. It also means they can create their own fertiliser for soil in their garden or for plants, rather than buying it. Photo courtesy of normanack (@commons. wikimedia. org) - granted under creative commons licence – attribution

Compost Here is Ms Green’s own compost – made with a wormery – basically a layered compost heap with a LOT of worms inside! Can you see the stages of how the food waste breaks down with the help of the worms to make compost?

You can now have a go at creating your own mini compost bin complete with worms! There is another version without worms in a couple of slides time if you prefer! You will need: A plastic bottle, cut down with a few holes in it (round bottomed two litre bottles are best. ) Thin pieces of fabric Cardboard pieces Shredded paper Fruit and vegetable scraps (cut into small pieces) Compost Small stones 5 to 6 tiger worms Scissors Plastic gloves Plant saucers Elastic bands Make sure you wash your hands carefully after you make your compost bottle. And take great care when handling the worms

You can also mark the top of where your compost comes to on the side of the bottle so that you can see how much it changes. For a version without worms see the next slide

For a version without worms: You will need: § A clear 2 ltr plastic bottle with a lid § Some garden soil- not shop bought stuff. § Some shredded paper, (not glossy stuff though) § Any of your fruit and vegetable peelings. (Not citrus and onion skin) § Some green grass clippings, hedge trimmings and leaves. Weed pullings work too just don’t put the roots or seed heads in. § Some water § Sellotape § Sharp scissors § Permanent markers watch this youtube clip for extra guidance https: //www. youtube. com/watch? v=k. A 3 q 07 pa. Nb. E

1. First, cut around the neck of the bottle to form a wider neck hole. 2. Add a layer of garden soil to the bottom of your bottle. around 2 cm – 4 cm deep. This introduces the bacteria needed to make black nutritious compost. 3. Next add a layer of peelings, anything from left over strawberries to potato peelings. 4. Add a another layer of each to your bottle. 5. Add some more soil then a layer of shredded paper. 6. Finally add another layer of soil and a layer of grass clippings or leaves. You can repeat this layering pattern until your bottle is full. 7. Use a fine spray bottle and dampen the materials in your jar with a little water. 8. Now your bottle is ready. Tape the top of the bottle closed to keep the moisture in 9. Make a mark on the side on the bottle where the top of your bottle comes to so you can see how much it changes. 10. Now just pop your ‘rot pot’ in a warm sunny place and let the magic begin. In 3 -6 weeks you’ll should see a big change in the contents of the bottle.

Let’s revisit our Key vocabulary Soil formation The process by which soil is formed organic matter The fraction of the soil that consists of plant or animal tissue which are decomposing top soil The uppermost layer of soil, which is high in nutrients and organic matter sub soil Subsoil is the layer of soil under the topsoil on the surface of the ground. Subsoil is usually paler in colour than the topsoil. base rock The rock that is underlying the other soil layers additions The things that get added to the soil losses The things that get removed from the soil Translocations transformations. Movements within the soil. Elements within the soil which change