LESSON 3 OTHER LAND RESOURCES C H A P T E R 6, C O N S E R V I N G O U R R E S O U R C E S

LESSON 3 OTHER LAND RESOURCES C H A P T E R 6, C O N S E R V I N G O U R R E S O U R C E S

OBJECTIVES Compare renewable and nonrenewable resources. Describe how human activities affect the environment.

MAIN IDEA Natural resources are classified as renewable or nonrenewable.

VOCABULARY renewable resource - materials from the environment that people use which can be replaced relatively quickly nonrenewable resource - materials from the environment that people use which are in a limited quantity pollution - a harmful change in the natural environment

smog - a mixture of smoke and fog, formed when smoke and fumes collect in moist, calm air acid rain - acid that is formed when the sulfur and nitrogen gases produced by burning fossil fuels combine with water vapor in the air and then fall to Earth as rain landfill - a specially designed place where garbage is deposited into a lined pit

biodegradable - the ability to break down naturally over time toxic waste - a collection of poisonous materials

WHAT ARE RENEWABLE RESOURCES? Scientists organize resources by the amount of time needed to produce them. They are categorized as renewable (water and solar energy) and nonrenewable resources (copper, coal, petroleum, etc.).

Availability is a factor in classifying resources. Some renewable resources such as trees and fish may be considered as nonrenewable if they are used quicker than can be replaced.

MINERALS AND SOIL Minerals come from the Earth s crust and is formed when magma cools and hardens. Diamonds are created deep in the Earth under intense heat and pressure. Other minerals include table salt, gypsum, quartz, and gold. They are nonrenewable resources.

Ores are rocks that contain useful substances like minerals. Gems, such as diamonds, emeralds, sapphires, and rubies, are minerals that are rare and beautiful.

Quartz is found as sand and inside granite. It is used to make glass and abrasives, computer chips (silicon), and used in watches and clocks. Minerals also make up granite and marble. Minerals give the marble its colors and luster.

Most rocks are covered in layers of soil made up of weathered rock, decayed plant and animal remains, air, and water. It can take hundreds or thousands of years for soil to form.

QUICK CHECK Main Idea and Details What is the difference between renewable and nonrenewable resources? Renewable resources can be reused or replaced within a relatively short period of time; examples include water and trees. Nonrenewable resources cannot be reused or replaced within a short period of time; examples include copper, coal, petroleum, gems, and other minerals.

Critical Thinking Why does it take many years for soil to form? It takes many years for rocks to weather and disintegrate, for plant and animal material to decay, and for sediments to replenish.

HOW DO FUELS FORM? Most of our energy comes from fossil fuels such as coal, oil, and natural gas. They formed over millions of years from the remains of ancient organisms. They are nonrenewable resources.

Coal formed when ancient plants in swamps died. The peat, dead plant material, built up and over time formed a thick layer. The layer of peat turned into lignite or eventually into bituminous coal from heat and pressure. With even more heat and pressure it could be turned into anthracite.

Coal is used to generate electrical energy. Many countries still use coal for electricity today. Large deposits of coal are strip mined along the Appalachian Mountains and in western states. In parts of Maine, Virginia and North Carolina peat is forming, and in millions of years it will turn into coal.

OIL AND NATURAL GAS Remains of organisms that once lived in the ocean form oil and natural gas. These organisms remains settled on the ocean floor and were buried by sand or other sediment. Over millions of years, pressure and heat turned the remains of these organisms into oil and natural gas.

Petroleum products are used for fuel. Limited deposits of oil and natural gas are found in North America, the Middle East, Indonesia, and Venezuela. Once the oil and gas is used up it will be gone. Geologists search for places where other oils and natural gases can be found.

QUICK CHECK Main Idea and Details How are fossil fuels formed? Much of our energy comes from fossil fuels such as coal, oil, and natural gas. These fuels formed over millions of years from remains of ancient organisms.

Critical Thinking If fossil fuels are still forming, why are they called nonrenewable resources? Fossil fuels are nonrenewable resources, because they take so long to form and their supply is limited.

HOW DO PEOPLE AFFECT THE ENVIRONMENT? Everyday things that people do affect the environment. Pollution is the harmful change to the natural environment. When Earth's land, water, or air overfills its capacity to absorb and recycle wastes naturally, it is called pollution.

Oil spills cause lots of damage. Oil that leaks from rigs and ships stay on the surface and makes feeding for seabirds difficult and sticks their wings together. It can also cover sea mammals. Contaminants sink to the bottom of the sea and causes damage. Oil also affects the costal ecosystem by washing up on the shore.

There are many valuable minerals found near earth's surface. Strip-mining involves scraping away areas of dirt and topsoil. When it rains top soil erodes and flows down into rivers and streams.

People may harm the soil through certain farming practices. When fields are cleared as much as possible during harvesting, there are no plants left to decay and restore the nutrients to the soil. Planting the same crops year after year removes the nutrients from the soil, then the wind and rain can carry the topsoil away.

Cutting down the trees in the forests without replacing them will cause soil erosion.

As population increases transportation grows so people have to build more roads and transit systems. Then there will be more cars and the cars leak oil and more gas will go into the atmosphere and that causes a lot of pollution. Construction sometimes causes rivers to change course. This will effect all the living organisms in that ecosystem.

HOW PEOPLE AFFECT WATER AND AIR Many ordinary things people do in daily life, such as bathing, washing clothes, and flushing toilets, can cause water and air pollution. These activities send harmful residues into the water. Factories can also cause pollution by dumping chemicals and wastes into bodies of water.

People working in agriculture sometimes apply fertilizers and pesticides to soil and crops. Homeowners use these for plant promotion growth and to kill insects. These chemicals can soak into the ground and harm many types of wildlife.

Fertilizer runoff can disrupt ecosystems. Masses of dead, decaying algae can use up vital oxygen dissolved in the water, killing fish and water plants. When people burn fuels to power factories, heat homes, or drive vehicles, they also produce air pollution. Smog is combination of "smoke" and "fog".

Nitrogen and sulfur gases produced by burning fossil fuels combine with water vapor in the air to form acids. Acid rain can pollute water and soil, kill plants and fish, and damage the stone and metal used in buildings and statues. The acid, can fall to earth as rain and snow.

QUICK CHECK Main Idea and Details What are some common activities that pollute air and water? Some common activities that pollute the water are when you bathe, wash clothes, and flush toilets; harmful activities that pollute the air are people burning fuels to power factories, heat homes, or drive vehicles.

Critical Thinking What might cause an increase in the number of people who have asthma? Air pollution and smog may increase the number of people that have asthma.

HOW DO PEOPLE AFFECT THE LAND? People produce large quantities of garbage every day. Most of this garbage ends up In landfills. In some areas garbage is simply dumped into open pits and left to rot. In other areas, garbage is burned in incinerators that give off large amounts of smoke.

Household garbage may contain harmful substances, as motor oil and weed killers. Foam cups and many plastic containers, are non-biodegradable. Since these materials do not break down easily, they add to the amount of trash that needs to be stored. Others are biodegradable, such as banana peels and paper.

Industrial material and waste may contain poisonous substances or metals. Toxic waste (ex. paints, cleaners, oils, and batteries) must be disposed carefully so as not to pollute soil, groundwater, rivers, and lakes. Toxic waste is poisonous to people, plants, and other organisms. It is important to follow directions on how to dispose of toxic materials.

Some systems break garbage into compounds and convert it into energy. These are good ways to deal with garbage.

QUICK CHECK Main Idea and Details How do people pollute the land? People produce large quantities of garbage every day. Most of this garbage ends up in landfills. Toxic waste, a collection of poisonous materials, must be disposed of carefully. Manufacturing can also be harmful.

Critical Thinking What are some possible problems with burning garbage to dispose of it? Smoke and the smell of burning garbage would pollute the air unless special equipment could somehow make the garbage burn more cleanly.