Conserving Land and Soil What you need to know

Land is a natural resource.  A natural resource is anything that occurs naturally in the environment and is used by people

Land is used in ways that change its appearance.  Agriculture  Mining  Development

What is Agriculture?  Agriculture requires fertile land to  Grow food for people to eat  Grow grass for animals to graze  Grow plants like cotton for clothing

What is Mining?  The removal of nonrenewable resources from land  Nonrenewable resources are those that can not be replaced by the earth  Types of mining are:  Strip mines remove top layer of land to obtain minerals like iron and copper  Tunnels are used to go deeper and bring out resources like coal  All methods mess up the land

What is Development?  When people change the land by  Building homes  Building roads, bridges  Building cities and buildings

Why is Soil Management Important?  It can take hundreds of years to form just a few centimeters of new soil.  Soil must  contain the minerals and nutrients that plants need to grow  Absorb, store, and filter water  Bacteria, fungus and other organisms must live in soil to break down wastes and dead organisms in the soil to make it fertile.

Layers of soil Use your text and draw the layers of soil and label. Define all the vocabulary terms: Topsoil, Litter, Subsoil, Bedrock. Do you know what humus is?

Poor Soil Use can cause:  Erosion can be caused by removing plants that hold the soil in place and wind blows soil away or water carries it away.  One way to prevent is to terrace farm on sloped hills and to always keep fields with plants  Nutrient Depletion occurs when the soil becomes less fertile and doesn’t have nutrients like nitrogen, phosphorus and potassium.  Farmers often rotate crops so they don’t always plant the same ones year after year. They can leave fields unplanted and let corn stalks just decompose.  Desertification occurs when a fertile area becomes like a desert and can no longer produce crops and cause starvation.  Caused by drought, overgrazing and cutting down trees.

Land Reclamation: this mined land must be restored  Is the process of restoring land to a more productive state  Land can be restored for agriculture, and as wildlife habitats  It is very expensive to reclaim land and it may never return to its original state.

How else do humans affect the environment?  Deforestation affects soil, the flow of water, climate and biodiversity of the plant and animal life in an area. Often trees are cut down to grow food and then plants can’t grow in the soil there.  Urbanization impacts Earth through the loss of land and through pollution of our land, air and water. We must be able to house our people but not if we can’t grow food for them or it we destroy all the animal homes.

Quiz 1. What is desertification and what causes it? 2. List 2 ways land is used in agriculture. 3. Explain why mining requires land reclamation. 4. List one way farmers can stop erosion of soil? 5. What is the layer beneath all soil called? 6. What is nutrient depletion? 7. How can urbanization impact our air and water?