Soils in the Environment

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All about SOIL

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Did you know that soil covers most of the land surfaces on our planet? Look all around. Soil is the base for farms, gardens, fields, forests, parks, and lawns. Soil can be very red like the soil found in Prince Edward Islands, or very black or brown like the soils in the Niagara Region. How does air help to make soil? Air helps to make soil when moving air or wind blows sand against rock and wears it slowly away. Little by little the rock becomes softer and slowly crumbles to become soil. This process takes thousands of years to form only a few centimetres of soil. How does water help to make soil? The weight of moving water can wear away rock. Nearly all the running water you see, such as in streams or rivers, carry little bits of sand and gravel. Some soil is made when glaciers and ice grind and break loose rocks. Glaciers then carry these loose bits of rock until the glacier melts and deposits the soil. Water splits and chips rocks by freezing and expanding. Rain wears away rocks and soaks decayed plants and animals into the soil. How do plants help to make soil? By sending their roots through the soil, plants break it up, making the soil better for growing. Even tiny roots are very strong and split apart big rocks. When plants die, plants decay, making the soil more fertile. Plants also help to keep soil in place and not blow away. How do animals help to make soil? When animals die, their bodies decay, adding important materials to the soil. Burrowing animals like moles, rabbits, and groundhogs help to mix the soil. The most important burrowing creature is the earthworm. Earthworm tunnels allow water and air to penetrate into hard soil. As earthworms travel through the soil in search of food, they produce waste that makes the soil more fertile.

THINK about it!

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Circle whether the following statements are true or false. Soil found in Prince Edward Island is very black TRUE FALSE Moving air blows sand against rock and wears it away. TRUE FALSE It takes just a few minutes to make soil. TRUE FALSE Running water carries bits of sand and gravel. TRUE FALSE It is impossible for water to break rocks. TRUE FALSE Tiny plant roots can split apart rocks. TRUE FALSE Fill in the blanks.

Air helps to make soil when _________________ _____________ or

_________________ blows against __________________________ and

wears it slowly away.

Water splits and chips rocks by ________________________ and

_______________________.

As earthworms travel through the soil in search of

_____________________, they produce _________________________

that makes soil more ___________________________.

Components of SOIL

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Did you know Did you know that soil is made up of many different types of materials? What the soil is made from will determine how people can use it. For example:  Soil Component: Sand •  water drains away quickly •  feels gritty •  very light to handle and quick to warm

up in spring •  most plants do not grow well in sand

Uses of Sand: •  make glass •  used in cement and

concrete •  grow cactus

Soil Component: Humus •  made up of decayed organic material

like plants and animals, and as a result it is very rich in nutrients

•  damp sticky texture •  gives soil a rich black or brown colour •  holds water better than sand •  allows plant roots to grow easily

Uses of Humus: •  excellent for growing

plants

Soil Component: Clay •  water does not enter clay easily

because the soil particles are packed together lightly

•  feels slippery and sticky •  difficult for plants to grow since there

is little air available

Uses of Clay: •  to make pottery •  to make bricks

THINK about it!

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Fill in the blanks.

The three components of soil are _____________ _____________ and

_______________. If the soil has a lot of sand, the water will drain

_____________. Plants do not typically grow well in _____________. We

use sand to grow _____________, make _____________, and it is also a

component of _____________ and _____________.  

Humus is made up of decayed _____________ and _____________

matter. It is very rich in __________________, making it excellent for

growing plants.

In clay, the particles are packed _____________ , making it difficult for

water to enter. It is difficult for plants to grow in clay soil because there is

little _____________ available.

Circle whether the following statements are true or false. Sand is the best soil to grow plants in TRUE FALSE We use clay soil to make pottery and bricks TRUE FALSE Humus feels slippery and sticky TRUE FALSE Sand feels gritty TRUE FALSE Humus gives soil a rich black, or brown colour TRUE FALSE

Types of SOIL

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Soil differs greatly from place to place, but all soil is made up of different amounts of three types of particles: sand, silt and clay.  Sand is the largest particle found in soil. When you rub it, it feels rough and gritty. Sand does not have many nutrients, but it dries quickly after rainfall, and it is good for drainage, which means it lets water flow through easily.

Silt is the medium-sized particle found in soil. Silt feels smooth and powdery when dry, and it feels slippery when wet. Silt can be packed down into a crust that makes it harder for water and air to pass through it.

Clay is the smallest particle found in soil. Clay feels smooth and hard as stone when dry, and feels sticky when wet. While clay can hold many nutrients, it does not allow much air or water to pass through. Too much clay can make the soil heavy and not good for growing plants.

Loam is a mix of sand, silt, and clay. It is the best type of soil for growing plants. Loam breaks up easily and holds moisture and nutrients, while still allowing some air and water to pass through.

Types of SOIL

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Finish this chart by filling in the textures and sizes for each type of soil particle.

  Clay Silt Sand

Texture

Particle Size

Advantage

holds onto water and nutrients  

 

good drainage, air passes

through it easily  

Disadvantage

easily packed down, causing less water and

air to pass through  

 

The Right Type of Soil

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Sandy soil has large particles.

 

There are many different types of soil. Soils are made up of ground up rock particles.

The type of soil depends of the size of the tiny rock particles.  

Clay soil has small particles.

 

Loam soil has a good mix of sand, humus

and clay   Most soils contain some organic matter which is made up of decaying plants and animals. Sometimes

organic matter is called humus.

Loam soil is best for

most plants.  

Comparing the Size of Soil Particles

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Sandy Soil  

Draw pictures showing the particles found in each type of soil.  

Clay Soil  

Loam Soil  

Soil Layers

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The Layers of Soil The HUMUS is the topmost layer of soil. It contains quite a bit of living material, plants, decaying leaves,

needles, moss, and more. This layer is thin and very dark in colour.

The TOPSOIL is the next layer down. It is made mostly of minerals, and most plant roots live here. This layer

is also dark in color due to the amount of decaying plant and animal matter.

The SUBSOIL layer is next. It is made

of sand, silt and clay that have not been broken down all the way, so it

usually has less organic material in it. It is also lighter in colour.

The PARENT MATERIAL is the next

layer down. It is mostly rock that has been slightly weathered. Not many

things live down there, except for the biggest tree roots.

The BEDROCK is the lowest layer of

soil. It is a solid rock layer.  

Soil is made up of distinct horizontal layers. If you could take an elevator ride through the Earth’s surface you would pass several distinct layers.

COMPOSTING: Nature’s Way of Recycling

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Did you know compost piles are amazing things? A compost pile is nature’s recycling system. A compost pile turns organic waste into compost or humus, a rich soil conditioner. Anything that once lived, like grass cuttings, fallen leaves, insect or animals remains, will slowly decay over time and go back into the earth. This is called decomposition. Composting allows you to see decomposition in action! Deep inside the compost pile there is a workforce of bacteria, fungi and other organisms like earthworms that work to break down or decompose organic waste. Earthworms help the process of composting by eating the earth materials. The eaten earth materials pass though the earthworm’s body, creating waste called castings. Castings add nutrients to the compost. Compost is dark, loose, soil-like substance or humus that can be used to improve the quality of the soil for growing. Waste found in the kitchen such as fruit and vegetable scraps, coffee, tea, bread, and even eggshells are good composting materials. Waste found outside such as lawn clippings, flowers, twigs and bits of other plants can also be added. Even torn up newspapers, and hair clippings can be composted! Unfortunately, not all materials can be used for composting. Materials such as meat, fish, and bones are smelly and will attract rodents like mice and rats. Therefore, these materials should not be used in a compost pile. Compost piles can be located outside in a backyard or garden, or inside in a bin or tub. Wherever the compost is located, nature will do a great job of turning unwanted organic waste into fresh new food for plants! Use finished compost wherever you may want to improve the soil quality. For example, spread finished compost into gardens, across your lawn, in flowerbeds, or around trees and shrubs.

COMPOSTING: Nature’s Way of Recycling

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1.  What advice would you give someone thinking about starting a compost pile?

________________________________________________________

________________________________________________________

________________________________________________________

________________________________________________________ 2.  “Composting is good for the environment.”

Using examples from the text, and your own words, explain why you think this statement is true or false.

________________________________________________________

________________________________________________________

________________________________________________________

________________________________________________________ 3  Using information from the text, and your own ideas, explain how

composting is nature’s way of recycling.

________________________________________________________

________________________________________________________

________________________________________________________

________________________________________________________

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Fill in the blanks to complete the paragraph, use the words listed below.

Backyard composting helps us _________________ the amount of waste

that goes into the dump. Also, it provides a nutrient-rich

_________________ that we can add to our gardens and lawns. Though

_________________ and _________________ products can be

composted, they should not be included in backyard composts because

they attract unwanted _________________ .

meat reduce dairy

soil rodents

Check the things that can go into compost bins:

From the House:

o  milk

o  seeds

o  newspaper

o  cheese

o  apple core

o  broken glass

o  orange peel

o  paper cups

From the Garden:

o  soft plant stems

o  old shovel

o  grass trimmings

o  fallen leaves

High HEAPS

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COMPOST HEAPS What can you do with a banana peel? What can be done with dead leaves? Why not make a compost heap? Never heard of one? A compost heap is a way to make garbage useful. It is done by making layers of certain garbage. A compost heap makes very rich soil. WHAT SHOULD YOU PUT IN A COMPOST HEAP? You can add anything that grew in the soil. HOW DO YOU MAKE A COMPOST HEAP? It is made by adding layers of garbage. Each layer needs to be sprinkled with water. Add your layers until your pile is about one metre high. Then you can start to mix it. Mix it every three days. Keep it covered. Keep it moist. It will be ready in about four months. Have any worms? Add them to your compost heap. They will help it. WHERE SHOULD YOU PUT A COMPOST HEAP Put it in a corner of your yard. You can build a special bin for it. Look at the compost heap below. What is in each layer? Look carefully. Write the name of each on the lines. Use words in the box below.

grass clippings vegetables leaves

cornstalks apple cores

hay sticks fruit

twigs tea bags

Guide to Composting

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Make a list of materials that can be composted and a second list of materials that cannot be composted.

Why should meat and dairy foods not be composted?

________________________________________________________________

________________________________________________________________

________________________________________________________________

________________________________________________________________

Compostable Materials  

Non- Compostable Materials  

_______________________

_______________________

_______________________

_______________________

_______________________

_______________________

_______________________

_______________________

_______________________

_______________________

_______________________

_______________________

_______________________

_______________________

Erasing Erosion

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Did you know there is a special name to describe water, wind, ice or living things wearing away or moving soil or rock? This is called erosion. Erosion can happen when ice, wind, or water breaks down components in the Earth. Erosion can be harmful to soil because it strips away precious nutrients and minerals. People have created different ways to help control erosion so that soil stays healthy for growing plants and animals.

One way to prevent soil erosion is to create a windbreak by plant ing trees . Trees prov ide organic matters such as leaves and hold the soil in place. Trees also provide shade and shelter for soil as well as preventing wind from sweeping across the land carrying the soil away.

Farmers often plant cover crops to stop erosion. Planting these crops during the spring and fall keeps the soil safe during the months when erosion is most likely to happen. Examples of cover crops include wheat, legumes, and oats.

Contour plowing happens when a farmer creates curved ridges in the soil to keep the soil from washing away during rainfall.

THINK about it!

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1.  What is erosion?

________________________________________________________

________________________________________________________

2.  Explain why erosion is harmful to soil.

________________________________________________________

________________________________________________________ 3  Using information from the text, and your own ideas, explain why it is

important to prevent erosion.

________________________________________________________

________________________________________________________

________________________________________________________

Erosion can happen when ice, wind or water TRUE FALSE breaks down components in the Earth Erosion can be harmful to soil because it TRUE FALSE adds precious nutrients and minerals Trees provide shade and shelter for soil TRUE FALSE Farmers often plant cover crops to stop TRUE FALSE erosion