Chp. 2 Earth’s Resources

2-1 Soil Natural Resources are materials removed from Earth & used by people. Fossil Fuels, Minerals, Trees

There are 2 types of natural resources: Nonrenewable resources & Renewable resources

Nonrenewable Resources Resources that can’t be replaced by nature. Fossil Fuels (coal, oil, gas), Minerals (copper, iron…)

Renewable Resources Resources that can be replaced by nature. Wood, Water, Soil

Land Uses Land is used for cities, highways, forests, pastures, farms, industry, & recreation.

Farmland must be used to its fullest potential Farmland must be used to its fullest potential. Must use productive methods. We have to use the same farmland year after year. Land for raising animals (pigs,chickens, cattle) is important. We must feed them in order to get beef from them.

Irrigation Process of supplying water to dry regions. It makes regions with dry land more suitable for farming.

Land Management Although soil is renewable, nature takes hundreds of years to replace 3 cm of topsoil. We have limited land resources. Different land provides different purposes. Farming must be planned so that the land will stay productive.

Land Management Techniques To prevent depletion 1) Crop Rotation To prevent erosion 1) contour plowing 2) strip cropping 3) terracing 4) wind breaks

Depletion Occurs when nutrients are removed from the soil. Planting corn removes nitrogen from soil. If you continue to plant the same thing year after year the soil will become depleted and won’t be as productive.

Crop Rotation A method of farming where rotating crops yearly will keep nutrients in the soil. Year 1 plant corn- takes nitrogen out of soil Year 2 plant peanuts or clover which puts nitrogen back in the soil.

Continue to alternate every year.

Contour Plowing Planting crops across the face of the slope of the land. It prevents water & wind from taking away big chunks of topsoil.

If you plant straight up and down, water will rush down the land taking the topsoil with it. Contour Plowing will slow the water runoff which will save the topsoil.

Strip Cropping Farming method where cover crops (hay, wheat) are planted in between strips of other crops to help hold down the soil.

Terracing Plowing a slope of land into a series of steps to prevent erosion. It slows down water runoff.

Windbreaks Planting rows of trees in between fields of crops to prevent erosion. It holds down the soil better.

The carrying off of soil by water and wind. EROSION The carrying off of soil by water and wind. Crops are grown in topsoil (the rich upper layer of soil). Topsoil is being lost by erosion.

Overgrazing Land that is too dry for crops may be used as a grassland for animals. If too many animals are on the grassland: 1. Animals eat all the grass 2. Topsoil is exposed to erosion This will lead to the grassland becoming a desert.

Desertification Process where dry grassland becomes a desert.

Land Reclamation Restoring mining land back to its original condition. Ex: river dredge in Hazleton.

Section 2-2 WATER

Where can we get new sources of fresh water? Desalination- process where we remove salt from the ocean water. (Boil water) Expensive to build, costly to operate, what do you do with the left over waste. 2. Icebergs/Glaciers- tow to coast, mine fresh water. MUST CONSERVE OUR FRESH WATER!

Section 2-3 MINERALS

MINERAL A naturally occuring chemical substance found in soil or rocks. Nonrenewable resource.

2 types of minerals Metallic Minerals- (copper, iron, aluminum) shiny surfaces, can conduct heat, can be hammered into thin sheets w/out breaking. Nonmetallic Minerals- (quartz, limestone, sulfur). Not shiny, poor conductors of heat, can’t be hammered into thin sheets w/out breaking.

Ore & Alloy Ore- minerals that can be mined for a profit. Alloy- a substance made of 2 or more metals. Brass or Steel.

Open Pit Mining 1. Located mineral deposit 2. Mine the ore 3. Remove impurities 4. Processed in plants 5. Plants make the final product

Negatives with Mining Scars the land Topsoil buried under tons of rock and is exposed to erosion

What can we do if we run out of minerals? Recycle or reuse minerals Find other materials to take their place Search the ocean floor- found nickel, manganese, cobalt, & copper.